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Experimental study of the effect of reflux rate during suspension polymerization on particle properties of PVC resin / Nasrin Etesami in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp.1997–2002 Titre : Experimental study of the effect of reflux rate during suspension polymerization on particle properties of PVC resin Type de document : texte imprimé Auteurs : Nasrin Etesami, Auteur ; Mohsen Nasr Esfahany, Auteur ; Roohollah Bagheri, Auteur Année de publication : 2010 Article en page(s) : pp.1997–2002 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Chemistry  Particle PVC  Polymerization  Resin Résumé : The particle morphological properties of poly(vinyl chloride) produced by suspension polymerization in a pilot-scale reactor under different reflux rates have been investigated. It was found that the monomer conversion decreased with increasing reflux rate. It was also observed that the cold plasticizer absorption (CPA) increased with reflux rate, whereas the bulk density (BD) and K value of the resin decreased. SEM micrographs showed that PVC resin with a rougher particle surface, more separate aggregates, and smaller primary particles was prepared at higher reflux rates. The particle size distribution determined by laser size analysis showed that the standard deviation of the particle size distribution and the mean particle size did not change significantly with reflux rate. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9008259 [article] Experimental study of the effect of reflux rate during suspension polymerization on particle properties of PVC resin [texte imprimé] / Nasrin Etesami, Auteur ; Mohsen Nasr Esfahany, Auteur ; Roohollah Bagheri, Auteur . - 2010 . - pp.1997–2002. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp.1997–2002 Mots-clés : Chemistry  Particle PVC  Polymerization  Resin Résumé : The particle morphological properties of poly(vinyl chloride) produced by suspension polymerization in a pilot-scale reactor under different reflux rates have been investigated. It was found that the monomer conversion decreased with increasing reflux rate. It was also observed that the cold plasticizer absorption (CPA) increased with reflux rate, whereas the bulk density (BD) and K value of the resin decreased. SEM micrographs showed that PVC resin with a rougher particle surface, more separate aggregates, and smaller primary particles was prepared at higher reflux rates. The particle size distribution determined by laser size analysis showed that the standard deviation of the particle size distribution and the mean particle size did not change significantly with reflux rate. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9008259

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Reactions of phenol, water, acetic acid, methanol, and 2-hydroxymethylfuran with olefins as models for bio-oil upgrading / Xulai Yang in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2003–2013 Titre : Reactions of phenol, water, acetic acid, methanol, and 2-hydroxymethylfuran with olefins as models for bio-oil upgrading Type de document : texte imprimé Auteurs : Xulai Yang, Auteur ; Sabornie Chatterjee, Auteur ; Zhijun Zhang, Auteur Année de publication : 2010 Article en page(s) : pp. 2003–2013 Note générale : Industrial et Chemistry Langues : Anglais (eng) Mots-clés : Phenol  Acetic acid  Hydroxymethylfuran  Olefins  Bio-oil  Octene  Alkylation Résumé : Model liquid phase reactions of 1-octene with phenol in the presence of water, acetic acid, methanol, and 2-hydroxymethylfuran, respectively, were carried out over acid catalysts for bio-oil upgrading, including 30 wt % acidic salt Cs2.5H0.5PW12O40 supported on K-10 clay (30%Cs2.5/K-10), Nafion (NR50) and Amberlyst 15. Temperatures from 40 to 120 °C were examined. Both catalysts had a high activity and selectivity for O-alkylation of phenol with 1-octene but not with 2,4,4-trimethylpentene. The presence of water, acetic acid, and methanol lowered the yield of alkylated phenols by the competitive formation of octanols and dioctyl ethers, octyl acetates, and methyl ethers, respectively. Higher O-alkylation selectivity was obtained at the expense of lower phenol conversion in the presence of water, methanol, or acetic acid. 30%Cs2.5/K-10 is an excellent water-tolerant catalyst while Amberlyst 15 decomposed at higher temperatures and higher water concentrations. 2-Hydroxymethylfuran deactivated catalysts significantly, indicating furan derivatives in bio-oil may require modification before upgrading with olefins. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900998d [article] Reactions of phenol, water, acetic acid, methanol, and 2-hydroxymethylfuran with olefins as models for bio-oil upgrading [texte imprimé] / Xulai Yang, Auteur ; Sabornie Chatterjee, Auteur ; Zhijun Zhang, Auteur . - 2010 . - pp. 2003–2013. Industrial et Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2003–2013 Mots-clés : Phenol  Acetic acid  Hydroxymethylfuran  Olefins  Bio-oil  Octene  Alkylation Résumé : Model liquid phase reactions of 1-octene with phenol in the presence of water, acetic acid, methanol, and 2-hydroxymethylfuran, respectively, were carried out over acid catalysts for bio-oil upgrading, including 30 wt % acidic salt Cs2.5H0.5PW12O40 supported on K-10 clay (30%Cs2.5/K-10), Nafion (NR50) and Amberlyst 15. Temperatures from 40 to 120 °C were examined. Both catalysts had a high activity and selectivity for O-alkylation of phenol with 1-octene but not with 2,4,4-trimethylpentene. The presence of water, acetic acid, and methanol lowered the yield of alkylated phenols by the competitive formation of octanols and dioctyl ethers, octyl acetates, and methyl ethers, respectively. Higher O-alkylation selectivity was obtained at the expense of lower phenol conversion in the presence of water, methanol, or acetic acid. 30%Cs2.5/K-10 is an excellent water-tolerant catalyst while Amberlyst 15 decomposed at higher temperatures and higher water concentrations. 2-Hydroxymethylfuran deactivated catalysts significantly, indicating furan derivatives in bio-oil may require modification before upgrading with olefins. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900998d

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Recovery of nickel from spent industrial catalysts using chelating agents / Koteswara R Vuyyuru in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2014–2024 Titre : Recovery of nickel from spent industrial catalysts using chelating agents Type de document : texte imprimé Auteurs : Koteswara R Vuyyuru, Auteur ; Kamal K. Pant, Auteur ; Venkatesan V Krishnan, Auteur Année de publication : 2010 Article en page(s) : pp. 2014–2024 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Recovery of Nickel  Chelating  Industrial Catalysts  Acid EDTA Résumé : The extraction of nickel from a spent primary steam reformer catalyst from an ammonia plant was carried out by chelation using ethylenediaminetetraacetic acid (EDTA) as the chelating agent. Ni recovery was optimized by varying the particle size distribution of catalyst (pretreatment of spent catalyst), stirring speed, temperature (particularly in an autoclave, where temperatures ranging from 100 to 200 °C were used), EDTA concentration, and solid-to-liquid ratio. Approximately 95% Ni recovery was achieved in the Ni extraction carried out under hydrothermal conditions in an autoclave, at temperatures of 150 °C and higher, over a 4-h period. The resulting Ni−EDTA complex was then “dechelated” using a mineral acid (H2SO4 and HNO3), resulting in the formation of a nickel nitrate or sulfate solution and the precipitation of EDTA (about 97% of the initial weight of EDTA was recovered). However, the chelation performance of Ni was shown to decrease with every successive recovery of EDTA (in the case of dechelation using H2SO4). EDX analysis of fresh and recovered EDTA established that fresh EDTA is a disodium salt whereas recovered EDTA is protonated. EDX analysis also indicated sulfur in the recovered EDTA when sulfuric acid was used for dechelation. TGA data showed a much larger weight loss in recovered EDTA in comparison to the fresh sample, probably because of a combination of two factors: the presence of sulfur species and the protonation of EDTA after recovery. It is likely that differences in recovered EDTA as evidenced by EDX analysis and TGA are responsible for the lowering the Ni chelation efficiency. This possibility is being investigated further as part of ongoing research. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901406e [article] Recovery of nickel from spent industrial catalysts using chelating agents [texte imprimé] / Koteswara R Vuyyuru, Auteur ; Kamal K. Pant, Auteur ; Venkatesan V Krishnan, Auteur . - 2010 . - pp. 2014–2024. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2014–2024 Mots-clés : Recovery of Nickel  Chelating  Industrial Catalysts  Acid EDTA Résumé : The extraction of nickel from a spent primary steam reformer catalyst from an ammonia plant was carried out by chelation using ethylenediaminetetraacetic acid (EDTA) as the chelating agent. Ni recovery was optimized by varying the particle size distribution of catalyst (pretreatment of spent catalyst), stirring speed, temperature (particularly in an autoclave, where temperatures ranging from 100 to 200 °C were used), EDTA concentration, and solid-to-liquid ratio. Approximately 95% Ni recovery was achieved in the Ni extraction carried out under hydrothermal conditions in an autoclave, at temperatures of 150 °C and higher, over a 4-h period. The resulting Ni−EDTA complex was then “dechelated” using a mineral acid (H2SO4 and HNO3), resulting in the formation of a nickel nitrate or sulfate solution and the precipitation of EDTA (about 97% of the initial weight of EDTA was recovered). However, the chelation performance of Ni was shown to decrease with every successive recovery of EDTA (in the case of dechelation using H2SO4). EDX analysis of fresh and recovered EDTA established that fresh EDTA is a disodium salt whereas recovered EDTA is protonated. EDX analysis also indicated sulfur in the recovered EDTA when sulfuric acid was used for dechelation. TGA data showed a much larger weight loss in recovered EDTA in comparison to the fresh sample, probably because of a combination of two factors: the presence of sulfur species and the protonation of EDTA after recovery. It is likely that differences in recovered EDTA as evidenced by EDX analysis and TGA are responsible for the lowering the Ni chelation efficiency. This possibility is being investigated further as part of ongoing research. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901406e

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Spectral studies of hydrogen bonding and interaction in the absorption processes of sulfur dioxide in poly(ethylene glycol) 400 + wter binary system / Jianbin Zhang in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2025–2030 Titre : Spectral studies of hydrogen bonding and interaction in the absorption processes of sulfur dioxide in poly(ethylene glycol) 400 + wter binary system Type de document : texte imprimé Auteurs : Jianbin Zhang, Auteur ; Fang Han, Auteur ; Xionghui Wei, Auteur Année de publication : 2010 Article en page(s) : pp. 2025–2030 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Sulfur Dioxide  Hydrogen  Poly ethylene glycol  PEG  Spectroscopy Résumé : In previous work, poly(ethylene glycol) 400 (PEG) (1) + water (2) solutions (PEGWs) were used as a promising medium for the absorption processes of SO2. When conventional UV, Fourier transform infrared (FTIR), and 1H NMR spectroscopic techniques were used for inspection of spectral changes of PEGWs with increasing SO2 concentration, the spectral results suggest that H2O can interact with PEG by hydrogen bonds in PEGW; furthermore, SO2 can interact with PEG in various PEGWs by hydrogen-bonding interactions in the absorption processes of SO2. The results of this work can be used to provide important absorption mechanism for the design and operation of the absorption and desorption process in flue gas desulfurization (FGD) with potential industrial application of PEG aqueous solutions. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014759 [article] Spectral studies of hydrogen bonding and interaction in the absorption processes of sulfur dioxide in poly(ethylene glycol) 400 + wter binary system [texte imprimé] / Jianbin Zhang, Auteur ; Fang Han, Auteur ; Xionghui Wei, Auteur . - 2010 . - pp. 2025–2030. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2025–2030 Mots-clés : Sulfur Dioxide  Hydrogen  Poly ethylene glycol  PEG  Spectroscopy Résumé : In previous work, poly(ethylene glycol) 400 (PEG) (1) + water (2) solutions (PEGWs) were used as a promising medium for the absorption processes of SO2. When conventional UV, Fourier transform infrared (FTIR), and 1H NMR spectroscopic techniques were used for inspection of spectral changes of PEGWs with increasing SO2 concentration, the spectral results suggest that H2O can interact with PEG by hydrogen bonds in PEGW; furthermore, SO2 can interact with PEG in various PEGWs by hydrogen-bonding interactions in the absorption processes of SO2. The results of this work can be used to provide important absorption mechanism for the design and operation of the absorption and desorption process in flue gas desulfurization (FGD) with potential industrial application of PEG aqueous solutions. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014759

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Removal of Ni(II) and Cr(VI) with titanium(IV) oxide nanoparticle agglomerates in fixed-bed columns / Sushanta Debnath in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2031–2039 Titre : Removal of Ni(II) and Cr(VI) with titanium(IV) oxide nanoparticle agglomerates in fixed-bed columns Type de document : texte imprimé Auteurs : Sushanta Debnath, Auteur ; Krishna Biswas, Auteur ; Uday Chand Ghosh, Auteur Année de publication : 2010 Article en page(s) : pp. 2031–2039 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Ni(II)  Cr(VI)  Titanium(IV)  Oxide Nanoparticle Résumé : Removal performances of Ni(II) and Cr(VI) from water were investigated using a packed fixed bed of agglomerated nanoparticles of hydrous titanium(IV) oxide (NHTO). The parameters varied were the (i) bed depth, (ii) flow rate, and (iii) feed solution concentrations. Comparison of breakthrough volumes indicated that the removal performance of Ni(II) (at pH 5.0 ± 0.1) was better than that of Cr(VI) (at pH 2.0 ± 0.1) by the NHTO fixed-bed columns. The breakthrough data were described better by the Thomas (R2 = 0.983−0.999) and bed-depth service time (BDST) (R2 = 0.992−0.998) models than by the Adams−Bohart model (R2 = 0.844−0.982). The Thomas model column capacity (q0) for Ni(II) was greater than that for Cr(VI) at any conditions. The breakthrough time (tb) of the BDST model increased with increasing bed depth of the NHTO columns, and the increase in tb was greater than the increase in bed depth. NHTO fixed-bed columns were able to treat Ni(II)- and Cr(VI)-contaminated industrial wastewater successfully. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014827 [article] Removal of Ni(II) and Cr(VI) with titanium(IV) oxide nanoparticle agglomerates in fixed-bed columns [texte imprimé] / Sushanta Debnath, Auteur ; Krishna Biswas, Auteur ; Uday Chand Ghosh, Auteur . - 2010 . - pp. 2031–2039. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2031–2039 Mots-clés : Ni(II)  Cr(VI)  Titanium(IV)  Oxide Nanoparticle Résumé : Removal performances of Ni(II) and Cr(VI) from water were investigated using a packed fixed bed of agglomerated nanoparticles of hydrous titanium(IV) oxide (NHTO). The parameters varied were the (i) bed depth, (ii) flow rate, and (iii) feed solution concentrations. Comparison of breakthrough volumes indicated that the removal performance of Ni(II) (at pH 5.0 ± 0.1) was better than that of Cr(VI) (at pH 2.0 ± 0.1) by the NHTO fixed-bed columns. The breakthrough data were described better by the Thomas (R2 = 0.983−0.999) and bed-depth service time (BDST) (R2 = 0.992−0.998) models than by the Adams−Bohart model (R2 = 0.844−0.982). The Thomas model column capacity (q0) for Ni(II) was greater than that for Cr(VI) at any conditions. The breakthrough time (tb) of the BDST model increased with increasing bed depth of the NHTO columns, and the increase in tb was greater than the increase in bed depth. NHTO fixed-bed columns were able to treat Ni(II)- and Cr(VI)-contaminated industrial wastewater successfully. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014827

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Catalytic hydrocracking of pyrolytic lignin to liquid fuel in supercritical ethanol / Zhe Tang in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2040–2046 Titre : Catalytic hydrocracking of pyrolytic lignin to liquid fuel in supercritical ethanol Type de document : texte imprimé Auteurs : Zhe Tang, Auteur ; Ying Zhang, Auteur ; Qingxiang Guo, Auteur Année de publication : 2010 Article en page(s) : pp. 2040–2046 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Pyrolysis  Hydrocracking  Ethanol Résumé : Pyrolytic lignins (PLs) are the major components in fast pyrolysis bio-oils and have detrimental effects on bio-oil properties. The existence of PLs also makes bio-oil upgrading rather difficult due to their nonvolatility and thermal instability. In this study, PL produced from rice husk was hydrocracked at 260 °C in supercritical ethanol under a hydrogen atmosphere by the use of Ru/ZrO2/SBA-15 or Ru/SO42−/ZrO2/SBA-15 catalyst. Trace amount of tar or coke was produced after the hydrocracking process, and most of the PL was converted into liquid fuel consisting of stable organic compounds with a heating value as high as 34.94 MJ/kg. The liquid product distribution was investigated by gas chromatography/mass spectrometry (GC-MS). The results demonstrated that, under supercritical ethanol conditions, Ru/ZrO2/SBA-15 and Ru/SO42−/ZrO2/SBA-15 were effective catalysts to convert PL to stable organic compounds such as phenols, guaiacols, anisoles, esters, light ketones, alcohols, long-chain alkanes. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015842 [article] Catalytic hydrocracking of pyrolytic lignin to liquid fuel in supercritical ethanol [texte imprimé] / Zhe Tang, Auteur ; Ying Zhang, Auteur ; Qingxiang Guo, Auteur . - 2010 . - pp. 2040–2046. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2040–2046 Mots-clés : Pyrolysis  Hydrocracking  Ethanol Résumé : Pyrolytic lignins (PLs) are the major components in fast pyrolysis bio-oils and have detrimental effects on bio-oil properties. The existence of PLs also makes bio-oil upgrading rather difficult due to their nonvolatility and thermal instability. In this study, PL produced from rice husk was hydrocracked at 260 °C in supercritical ethanol under a hydrogen atmosphere by the use of Ru/ZrO2/SBA-15 or Ru/SO42−/ZrO2/SBA-15 catalyst. Trace amount of tar or coke was produced after the hydrocracking process, and most of the PL was converted into liquid fuel consisting of stable organic compounds with a heating value as high as 34.94 MJ/kg. The liquid product distribution was investigated by gas chromatography/mass spectrometry (GC-MS). The results demonstrated that, under supercritical ethanol conditions, Ru/ZrO2/SBA-15 and Ru/SO42−/ZrO2/SBA-15 were effective catalysts to convert PL to stable organic compounds such as phenols, guaiacols, anisoles, esters, light ketones, alcohols, long-chain alkanes. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015842

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Synthesis of a novel macroporous silica-calix[4] arene-crown polymeric composite and Its adsorption for alkali metals and alkaline-earth metals / Anyun Zhang in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2047–2054 Titre : Synthesis of a novel macroporous silica-calix[4] arene-crown polymeric composite and Its adsorption for alkali metals and alkaline-earth metals Type de document : texte imprimé Auteurs : Anyun Zhang, Auteur ; Qihui Hu, Auteur ; Zhifang Chai, Auteur Année de publication : 2010 Article en page(s) : pp. 2047–2054 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Macroporous  Calix[4]  Polymeic  Adsorption Résumé : A macroporous silica-based 1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-calix[4]arene (Calix[4]arene-R14) supramolecular recognition polymeric composite, (Calix[4] + MODB)/SiO2−P, was synthesized. The synthesis was performed by impregnation and immobilization of Calix[4]arene-R14 and methyloctyl-2-dimethylbutanemide (MODB) molecules in the pores of a macroporous SiO2−P polymeric particle support with a mean diameter of 50 μm. MODB was used to modify the Calix[4]arene-R14 through intermolecular interaction force. The static-state adsorption of some typical alkali metals and alkaline-earth metals such as Na(I), K(I), Cs(I), Rb(I), Sr(II), and Ba(II) onto (Calix[4] + MODB)/SiO2−P was investigated. The effects of contact time, HNO3 concentration in the range of 0.3−7.0 M, and temperature on the adsorption were examined. (Calix[4] + MODB)/SiO2−P exhibited strong adsorption ability and excellent selectivity for Cs(I) over all tested elements, which showed weak or almost no adsorption except for Rb(I). The adsorption onto (Calix[4] + MODB)/SiO2−P of the tested metals in HNO3 medium was exothermic. The thermodynamic parameters for the adsorptions of Cs(I) and Rb(I) were determined. It was found that, in 3.0 M HNO3, application of the (Calix[4] + MODB)/SiO2−P polymeric composite in the partitioning of Cs(I), one of the heat generators, from highly active liquid waste in the SPEC (strontium/cesium partitioning from HLW by extraction chromatography) process is promising. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901622y [article] Synthesis of a novel macroporous silica-calix[4] arene-crown polymeric composite and Its adsorption for alkali metals and alkaline-earth metals [texte imprimé] / Anyun Zhang, Auteur ; Qihui Hu, Auteur ; Zhifang Chai, Auteur . - 2010 . - pp. 2047–2054. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2047–2054 Mots-clés : Macroporous  Calix[4]  Polymeic  Adsorption Résumé : A macroporous silica-based 1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-calix[4]arene (Calix[4]arene-R14) supramolecular recognition polymeric composite, (Calix[4] + MODB)/SiO2−P, was synthesized. The synthesis was performed by impregnation and immobilization of Calix[4]arene-R14 and methyloctyl-2-dimethylbutanemide (MODB) molecules in the pores of a macroporous SiO2−P polymeric particle support with a mean diameter of 50 μm. MODB was used to modify the Calix[4]arene-R14 through intermolecular interaction force. The static-state adsorption of some typical alkali metals and alkaline-earth metals such as Na(I), K(I), Cs(I), Rb(I), Sr(II), and Ba(II) onto (Calix[4] + MODB)/SiO2−P was investigated. The effects of contact time, HNO3 concentration in the range of 0.3−7.0 M, and temperature on the adsorption were examined. (Calix[4] + MODB)/SiO2−P exhibited strong adsorption ability and excellent selectivity for Cs(I) over all tested elements, which showed weak or almost no adsorption except for Rb(I). The adsorption onto (Calix[4] + MODB)/SiO2−P of the tested metals in HNO3 medium was exothermic. The thermodynamic parameters for the adsorptions of Cs(I) and Rb(I) were determined. It was found that, in 3.0 M HNO3, application of the (Calix[4] + MODB)/SiO2−P polymeric composite in the partitioning of Cs(I), one of the heat generators, from highly active liquid waste in the SPEC (strontium/cesium partitioning from HLW by extraction chromatography) process is promising. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901622y

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Selective leaching of steelmaking slag for indirect CO2 mineral sequestration / Weijun Bao in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2055–2063 Titre : Selective leaching of steelmaking slag for indirect CO2 mineral sequestration Type de document : texte imprimé Auteurs : Weijun Bao, Auteur ; Huiquan Li, Auteur ; Yi Zhang, Auteur Année de publication : 2010 Article en page(s) : pp. 2055–2063 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : CO2  Steelmaking  Lleaching  Calcium ions  Indirect CO2 mineral Résumé : Indirect CO2 mineral sequestration, which could make CO2 fixate into precipitated calcium carbonate (PCC) of value-added products, is an important technology that is used to reduce greenhouse gas emissions economically. It can be conducted in two steps, one of which has been investigated in the previous paper. In this work, extraction of calcium ions from steelmaking slag using a novel leaching medium, which involves organic solvent tributyl phosphate (TBP), acetic acid, and ultrapure water, was studied. Several operating variables, including stirring speed, phase-volume ratio, organic solvent-to-solid ratio, initial acetic acid concentration, acid-to-slag ratio, reaction temperature, and reaction time were investigated. It was found that the leaching process could be divided into three regions according to the acid-to-slag ratio. The first region below 0.5 g/g was characterized by the acid-to-solid ratio; the second region above 0.5 g/g but below 1.0 g/g was characterized by the acid-to-solid ratio; and the third region above 1.0 g/g was characterized by the acid-to-solid ratio. When the acid-to-solid ratio was below 1.0 g/g, only Ca and Mg could be leached with the maximum leached ratios of 75% and 35%, respectively. Moreover, the leaching behaviors of Ca, Mg, Fe, Al, and Si were greatly affected by reaction temperature and reaction time. Results show that the calcium ions can be effectively and selectively extracted from the steelmaking slag and that the reaction medium can be recovered and recycled with high efficiency. These are the keys to indirect CO2 mineral sequestration. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801850s [article] Selective leaching of steelmaking slag for indirect CO2 mineral sequestration [texte imprimé] / Weijun Bao, Auteur ; Huiquan Li, Auteur ; Yi Zhang, Auteur . - 2010 . - pp. 2055–2063. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2055–2063 Mots-clés : CO2  Steelmaking  Lleaching  Calcium ions  Indirect CO2 mineral Résumé : Indirect CO2 mineral sequestration, which could make CO2 fixate into precipitated calcium carbonate (PCC) of value-added products, is an important technology that is used to reduce greenhouse gas emissions economically. It can be conducted in two steps, one of which has been investigated in the previous paper. In this work, extraction of calcium ions from steelmaking slag using a novel leaching medium, which involves organic solvent tributyl phosphate (TBP), acetic acid, and ultrapure water, was studied. Several operating variables, including stirring speed, phase-volume ratio, organic solvent-to-solid ratio, initial acetic acid concentration, acid-to-slag ratio, reaction temperature, and reaction time were investigated. It was found that the leaching process could be divided into three regions according to the acid-to-slag ratio. The first region below 0.5 g/g was characterized by the acid-to-solid ratio; the second region above 0.5 g/g but below 1.0 g/g was characterized by the acid-to-solid ratio; and the third region above 1.0 g/g was characterized by the acid-to-solid ratio. When the acid-to-solid ratio was below 1.0 g/g, only Ca and Mg could be leached with the maximum leached ratios of 75% and 35%, respectively. Moreover, the leaching behaviors of Ca, Mg, Fe, Al, and Si were greatly affected by reaction temperature and reaction time. Results show that the calcium ions can be effectively and selectively extracted from the steelmaking slag and that the reaction medium can be recovered and recycled with high efficiency. These are the keys to indirect CO2 mineral sequestration. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801850s

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Operating conditions for the pyrolysis of poly-(ethylene terephthalate) in a conical spouted-bed reactor / Maite Artetxe in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2064–2069 Titre : Operating conditions for the pyrolysis of poly-(ethylene terephthalate) in a conical spouted-bed reactor Type de document : texte imprimé Auteurs : Maite Artetxe, Auteur ; Gartzen Lopez, Auteur ; Maider Amutio, Auteur Année de publication : 2010 Article en page(s) : pp. 2064–2069 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Pyrolysis  Poly-ethylene terephthalate  PET  Conical reactor  plastic Résumé : Continuous pyrolysis of poly-(ethylene terephthalate) (PET) was performed in a conical spouted-bed reactor. This reactor is especially suitable for this process, because of its excellent hydrodynamic behavior and its versatility. An optimization of the operating conditions has been performed to avoid particle agglomeration and defluidization, given that these are serious problems that hinder plastic waste pyrolysis. Moreover, the influence of temperature in the pyrolysis product distribution was studied in the range of 500−600 °C. PET pyrolysis led to a high yield of gas fraction, a low amount of liquids, a significant yield of solid fraction, and a solid residue that remained in the reactor coating sand particles. The main products obtained are carbon monoxide, carbon dioxide, benzoic acid, and acetaldehyde. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900557c [article] Operating conditions for the pyrolysis of poly-(ethylene terephthalate) in a conical spouted-bed reactor [texte imprimé] / Maite Artetxe, Auteur ; Gartzen Lopez, Auteur ; Maider Amutio, Auteur . - 2010 . - pp. 2064–2069. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2064–2069 Mots-clés : Pyrolysis  Poly-ethylene terephthalate  PET  Conical reactor  plastic Résumé : Continuous pyrolysis of poly-(ethylene terephthalate) (PET) was performed in a conical spouted-bed reactor. This reactor is especially suitable for this process, because of its excellent hydrodynamic behavior and its versatility. An optimization of the operating conditions has been performed to avoid particle agglomeration and defluidization, given that these are serious problems that hinder plastic waste pyrolysis. Moreover, the influence of temperature in the pyrolysis product distribution was studied in the range of 500−600 °C. PET pyrolysis led to a high yield of gas fraction, a low amount of liquids, a significant yield of solid fraction, and a solid residue that remained in the reactor coating sand particles. The main products obtained are carbon monoxide, carbon dioxide, benzoic acid, and acetaldehyde. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900557c

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Measurement of dynamic liquid distributions in a fixed bed using electrical capacitance tomography and capacitance wire-mesh sensor / Bartosz Matusiak in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2070–2077 Titre : Measurement of dynamic liquid distributions in a fixed bed using electrical capacitance tomography and capacitance wire-mesh sensor Type de document : texte imprimé Auteurs : Bartosz Matusiak, Auteur ; Marco Jose da Silva, Auteur ; Uwe Hampel, Auteur Année de publication : 2010 Article en page(s) : pp. 2070–2077 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Measurement of Dynamic  Electrical Capacitance  Tomography  Wire-Mesh Sensor  Media supply  ECT Résumé : An intricate problem associated with fixed bed operation is liquid maldistribution, which denotes the fact that the liquid does not homogeneously flow through the bed. In a comparative study we evaluated two capacitance imaging methods—capacitance wire-mesh sensor and electrical capacitance tomography (ECT)—with respect to their capability of measuring static and dynamic liquid holdup in a fixed bed. The capacitance wire-mesh sensor as an invasive instrument is able to disclose flow structures at higher spatial resolution and was therefore considered the reference instrument for liquid holdup measurement. We found that both methods predict dynamic liquid holdup in the column in a similar way with only small systematic deviation. The results therefore prove that noninvasive electrical capacitance tomography can reliably measure cross-sectional dynamic liquid holdup in a fixed bed, even with a simple and fast linear back projection reconstruction algorithm. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/toc/IECRED/49/5 [article] Measurement of dynamic liquid distributions in a fixed bed using electrical capacitance tomography and capacitance wire-mesh sensor [texte imprimé] / Bartosz Matusiak, Auteur ; Marco Jose da Silva, Auteur ; Uwe Hampel, Auteur . - 2010 . - pp. 2070–2077. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2070–2077 Mots-clés : Measurement of Dynamic  Electrical Capacitance  Tomography  Wire-Mesh Sensor  Media supply  ECT Résumé : An intricate problem associated with fixed bed operation is liquid maldistribution, which denotes the fact that the liquid does not homogeneously flow through the bed. In a comparative study we evaluated two capacitance imaging methods—capacitance wire-mesh sensor and electrical capacitance tomography (ECT)—with respect to their capability of measuring static and dynamic liquid holdup in a fixed bed. The capacitance wire-mesh sensor as an invasive instrument is able to disclose flow structures at higher spatial resolution and was therefore considered the reference instrument for liquid holdup measurement. We found that both methods predict dynamic liquid holdup in the column in a similar way with only small systematic deviation. The results therefore prove that noninvasive electrical capacitance tomography can reliably measure cross-sectional dynamic liquid holdup in a fixed bed, even with a simple and fast linear back projection reconstruction algorithm. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/toc/IECRED/49/5

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New Co/La/SiO2 catalyst for the simultaneous production of C2H4 and syngas from CH4 with Na2WO4/Mn/SiO2 / Songtao Ren in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2078–2083 Titre : New Co/La/SiO2 catalyst for the simultaneous production of C2H4 and syngas from CH4 with Na2WO4/Mn/SiO2 Type de document : texte imprimé Auteurs : Songtao Ren, Auteur ; Song Qin, Auteur ; Jianqiang Zhu, Auteur Année de publication : 2010 Article en page(s) : pp. 2078–2083 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Catalyst  Syngas  Co−  La/SiO2  Na2WO4/Mn/SiO2 Résumé : A new dual catalyst bed system with Na2WO4/Mn/SiO2 in the first layer and Co−La/SiO2 in the second layer has been applied in the conversion of methane to ethylene and syngas simultaneously. The effects of flow velocity and the ratio of methane to oxygen on the catalytic performance were investigated. The results showed that, when F = 150 mL/min, CH4/O2 = 2.5, the amount of Na2WO4/Mn/SiO2 was 0.27 g in the first bed, and that of Co−La/SiO2 was 0.1 g in the second bed, the expected mixture of C2H4/H2/CO = 1/1/1 with a total yield of 20.6% for C2H4 + CO was achieved, which could be directly used as a feedstock to produce propanal by hydroformylation of ethylene. The new process provides an efficient method for the utilization of CO2, H2O, and thermicity. The Co−La/SiO2 catalyst on the second layer was found to possess a catalytic performance for both partial oxidation of methane and oxidative coupling of methane reactions. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9010468 [article] New Co/La/SiO2 catalyst for the simultaneous production of C2H4 and syngas from CH4 with Na2WO4/Mn/SiO2 [texte imprimé] / Songtao Ren, Auteur ; Song Qin, Auteur ; Jianqiang Zhu, Auteur . - 2010 . - pp. 2078–2083. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2078–2083 Mots-clés : Catalyst  Syngas  Co−  La/SiO2  Na2WO4/Mn/SiO2 Résumé : A new dual catalyst bed system with Na2WO4/Mn/SiO2 in the first layer and Co−La/SiO2 in the second layer has been applied in the conversion of methane to ethylene and syngas simultaneously. The effects of flow velocity and the ratio of methane to oxygen on the catalytic performance were investigated. The results showed that, when F = 150 mL/min, CH4/O2 = 2.5, the amount of Na2WO4/Mn/SiO2 was 0.27 g in the first bed, and that of Co−La/SiO2 was 0.1 g in the second bed, the expected mixture of C2H4/H2/CO = 1/1/1 with a total yield of 20.6% for C2H4 + CO was achieved, which could be directly used as a feedstock to produce propanal by hydroformylation of ethylene. The new process provides an efficient method for the utilization of CO2, H2O, and thermicity. The Co−La/SiO2 catalyst on the second layer was found to possess a catalytic performance for both partial oxidation of methane and oxidative coupling of methane reactions. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9010468

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Kinetics of limonene hydrogenation in high-pressure CO2 at variation of hydrogen pressure / V. I. Anikeev in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2084–2090 Titre : Kinetics of limonene hydrogenation in high-pressure CO2 at variation of hydrogen pressure Type de document : texte imprimé Auteurs : V. I. Anikeev, Auteur ; A. Yermakova, Auteur ; Ewa Bogel-Lukasik, Auteur Année de publication : 2010 Article en page(s) : pp. 2084–2090 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Kinetics of Limonene  hydrogen pressure  CO2 Résumé : A mechanism of limonene hydrogenation in high-pressure CO2 has been suggested using the experimental data. The experimental data on limonene hydrogenation in high-pressure CO2 were processed to elucidate the reaction mechanism and calculate the kinetic constants in rate equations for the proposed reaction scheme. The relationship between the total rate constant of limonene reduction and hydrogen pressure has been found. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9010996 [article] Kinetics of limonene hydrogenation in high-pressure CO2 at variation of hydrogen pressure [texte imprimé] / V. I. Anikeev, Auteur ; A. Yermakova, Auteur ; Ewa Bogel-Lukasik, Auteur . - 2010 . - pp. 2084–2090. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2084–2090 Mots-clés : Kinetics of Limonene  hydrogen pressure  CO2 Résumé : A mechanism of limonene hydrogenation in high-pressure CO2 has been suggested using the experimental data. The experimental data on limonene hydrogenation in high-pressure CO2 were processed to elucidate the reaction mechanism and calculate the kinetic constants in rate equations for the proposed reaction scheme. The relationship between the total rate constant of limonene reduction and hydrogen pressure has been found. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9010996

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Alkylation of toluene with t-butyl alcohol over zeolite catalysts / Hong-jun Dong in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2091–2095 Titre : Alkylation of toluene with t-butyl alcohol over zeolite catalysts Type de document : texte imprimé Auteurs : Hong-jun Dong, Auteur ; Shi Li, Auteur Année de publication : 2010 Article en page(s) : pp. 2091–2095 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Alkylation  Toluene  t-Butyl Alcohol  Zeolite Catalysts Résumé : Alkylation of toluene with tert-butylalcohol was investigated over three zeolite catalysts (HY, Hβ, and HMCM-22). The acid properties of zeolites were characterized by FT-IR. The fact that the reaction was influenced by the mount of acid was discussed emphatically, and the reaction temperature on conversion of toluene and selectivity for 4-tert-butyl toluene was also studied. The main products have been identified as 4-tert-butyltoluene and 3-tert-butyltoluene. The best result was obtained when temperature was 473 K, the space velocity was 4.0 h−1, and the mole ratio of toluene to tert-butylalcohol was 6. Zeolite HMCM-22, with the highest total acid and the lowest ratio of the total B acid to the total L acid, possessed high activity for toluene conversion and high paraselectivity over the three types of zeolite catalysts. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901080t [article] Alkylation of toluene with t-butyl alcohol over zeolite catalysts [texte imprimé] / Hong-jun Dong, Auteur ; Shi Li, Auteur . - 2010 . - pp. 2091–2095. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2091–2095 Mots-clés : Alkylation  Toluene  t-Butyl Alcohol  Zeolite Catalysts Résumé : Alkylation of toluene with tert-butylalcohol was investigated over three zeolite catalysts (HY, Hβ, and HMCM-22). The acid properties of zeolites were characterized by FT-IR. The fact that the reaction was influenced by the mount of acid was discussed emphatically, and the reaction temperature on conversion of toluene and selectivity for 4-tert-butyl toluene was also studied. The main products have been identified as 4-tert-butyltoluene and 3-tert-butyltoluene. The best result was obtained when temperature was 473 K, the space velocity was 4.0 h−1, and the mole ratio of toluene to tert-butylalcohol was 6. Zeolite HMCM-22, with the highest total acid and the lowest ratio of the total B acid to the total L acid, possessed high activity for toluene conversion and high paraselectivity over the three types of zeolite catalysts. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901080t

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Au/CuOx-TiO2 catalysts for preferential oxidation of CO in hydrogen sStream / Palanivelu Sangeetha in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2096–2102 Titre : Au/CuOx-TiO2 catalysts for preferential oxidation of CO in hydrogen sStream Type de document : texte imprimé Auteurs : Palanivelu Sangeetha, Auteur ; Bin Zhao, Auteur ; Chen, Yu-Wen, Auteur Année de publication : 2010 Article en page(s) : pp. 2096–2102 Note générale : Industrial Chemisty Langues : Anglais (eng) Mots-clés : Catalysts  Au/CuOx-TiO2  Preferential Oxidation Résumé : A series of Au/CuOx−TiO2 catalysts with various Cu/Ti atomic ratios were prepared by deposition−precipitation method. The catalysts were characterized by inductively coupled plasma−mass spectrometry, X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The preferential oxidation of CO in H2 stream (PROX) on these catalysts was carried out in a fixed bed microreactor with a gas mixture (CO:O2:H2:He = 1.33:1.33:65.33:32.01 by volume ratios) was fed with a space velocity of 30000 mL/(g·h). Au/CuOx−TiO2 with various Cu/Ti atomic ratios showed similar gold particle size (2.3−2.5 nm). The gold in the starting material was almost totally loaded on the CuOx−TiO2 support at pH = 7. Au/CuOx−TiO2 catalysts with gold content of 1 wt % and calcined at 180 °C had superior catalytic activity and selectivity for CO oxidation at temperature of 80 °C. Au/CuOx−TiO2 (Cu/Ti = 4.8/95.2) had a CO conversion of 100% at 80 °C, and CO selectivity reaches 68%. Gold particles were well dispersed and stable on the support. Even after PROX reaction at 80 °C for a long time, most of the particles still maintained at 2.4 nm. The CO conversion slightly decreased from 100% to 95%, and CO selectivity was nearly the same. Au/CuOx−TiO2 is a highly effective and thermally stable catalyst for PROX reaction compared with Au/TiO2 catalyst. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901233e [article] Au/CuOx-TiO2 catalysts for preferential oxidation of CO in hydrogen sStream [texte imprimé] / Palanivelu Sangeetha, Auteur ; Bin Zhao, Auteur ; Chen, Yu-Wen, Auteur . - 2010 . - pp. 2096–2102. Industrial Chemisty Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2096–2102 Mots-clés : Catalysts  Au/CuOx-TiO2  Preferential Oxidation Résumé : A series of Au/CuOx−TiO2 catalysts with various Cu/Ti atomic ratios were prepared by deposition−precipitation method. The catalysts were characterized by inductively coupled plasma−mass spectrometry, X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The preferential oxidation of CO in H2 stream (PROX) on these catalysts was carried out in a fixed bed microreactor with a gas mixture (CO:O2:H2:He = 1.33:1.33:65.33:32.01 by volume ratios) was fed with a space velocity of 30000 mL/(g·h). Au/CuOx−TiO2 with various Cu/Ti atomic ratios showed similar gold particle size (2.3−2.5 nm). The gold in the starting material was almost totally loaded on the CuOx−TiO2 support at pH = 7. Au/CuOx−TiO2 catalysts with gold content of 1 wt % and calcined at 180 °C had superior catalytic activity and selectivity for CO oxidation at temperature of 80 °C. Au/CuOx−TiO2 (Cu/Ti = 4.8/95.2) had a CO conversion of 100% at 80 °C, and CO selectivity reaches 68%. Gold particles were well dispersed and stable on the support. Even after PROX reaction at 80 °C for a long time, most of the particles still maintained at 2.4 nm. The CO conversion slightly decreased from 100% to 95%, and CO selectivity was nearly the same. Au/CuOx−TiO2 is a highly effective and thermally stable catalyst for PROX reaction compared with Au/TiO2 catalyst. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901233e

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Methanol to olefin over ca-modified HZSM-5 zeolites / Suhong Zhang in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2103–2106 Titre : Methanol to olefin over ca-modified HZSM-5 zeolites Type de document : texte imprimé Auteurs : Suhong Zhang, Auteur ; Bianling Zhang, Auteur ; Zhixian Gao, Auteur Année de publication : 2010 Article en page(s) : pp. 2103–2106 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Methanol of Olefin  Zeolites HZSM-5 Résumé : A series of HZSM-5 zeolites modified with various Ca loadings were prepared by an incipient impregnation technique and characterized by Fourier transform infrared spectra of adsorbed pyridine and temperature-programmed desorption of NH3 and CO2. Methanol to olefin (MTO) over Ca-modified HZSM-5 zeolites was performed in a flow-type fixed bed reactor. The results indicated that Ca modification increased both the catalytic stability and the light olefin selectivity. However, an excess Ca loading resulted in an inferior catalytic performance. Hence, there was an optimal Ca loading for a specific HZSM-5, and the thus prepared Ca/HZSM-5 had little free Brönsted acid sites and presented the best catalytic performance of MTO. A possible mechanism for MTO involving acid−base centers on Ca-modified HZSM-5 zeolites has been suggested on the basis of the results obtained. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901446m [article] Methanol to olefin over ca-modified HZSM-5 zeolites [texte imprimé] / Suhong Zhang, Auteur ; Bianling Zhang, Auteur ; Zhixian Gao, Auteur . - 2010 . - pp. 2103–2106. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2103–2106 Mots-clés : Methanol of Olefin  Zeolites HZSM-5 Résumé : A series of HZSM-5 zeolites modified with various Ca loadings were prepared by an incipient impregnation technique and characterized by Fourier transform infrared spectra of adsorbed pyridine and temperature-programmed desorption of NH3 and CO2. Methanol to olefin (MTO) over Ca-modified HZSM-5 zeolites was performed in a flow-type fixed bed reactor. The results indicated that Ca modification increased both the catalytic stability and the light olefin selectivity. However, an excess Ca loading resulted in an inferior catalytic performance. Hence, there was an optimal Ca loading for a specific HZSM-5, and the thus prepared Ca/HZSM-5 had little free Brönsted acid sites and presented the best catalytic performance of MTO. A possible mechanism for MTO involving acid−base centers on Ca-modified HZSM-5 zeolites has been suggested on the basis of the results obtained. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901446m

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Kinetic evidence of the maillard reaction in hydrothermal biomass processing / Andrew A. Peterson in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2107–2117 Titre : Kinetic evidence of the maillard reaction in hydrothermal biomass processing : glucose-glycine interactions in high-temperature, high-pressure water Type de document : texte imprimé Auteurs : Andrew A. Peterson, Auteur ; Russell P. Lachance, Auteur ; Jefferson W. Tester, Auteur Année de publication : 2010 Article en page(s) : pp. 2107–2117 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Kinetic Evidence  Hydrothermal  Biomass  Glucose-glycine Résumé : Kinetic and mechanistic evidence is presented of the occurrence of a Maillard-type reaction under conditions of interest to hydrothermal biomass processing. Glucose−glycine mixtures were reacted at 250 °C and 10 MPa in an excess of water; both glucose and glycine were found to strongly influence the destruction kinetics of the other species and to result in quantitative and qualitative changes, such as strong absorbance at 420 nm and the production of a dark brown appearance and nutty odor, which are characteristic of the Maillard reaction. The presence of glucose always resulted in higher glycine destruction; the presence of glycine resulted in increased or decreased glucose destruction, depending on initial concentrations, which is consistent with results reported in the literature for lower temperature Maillard reactions. Surrogate compounds that contain the same chemical functional groups also resulted in similar trends. As a result of this reaction, the presence of proteins and amino acids in biomass feedstocks can be expected to result in processing difficulties at hydrothermal conditions: these difficulties will include fouling of process equipment, the quenching of desired reaction pathways, and difficulty in achieving separations between aqueous and oil phases produced. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014809 [article] Kinetic evidence of the maillard reaction in hydrothermal biomass processing : glucose-glycine interactions in high-temperature, high-pressure water [texte imprimé] / Andrew A. Peterson, Auteur ; Russell P. Lachance, Auteur ; Jefferson W. Tester, Auteur . - 2010 . - pp. 2107–2117. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2107–2117 Mots-clés : Kinetic Evidence  Hydrothermal  Biomass  Glucose-glycine Résumé : Kinetic and mechanistic evidence is presented of the occurrence of a Maillard-type reaction under conditions of interest to hydrothermal biomass processing. Glucose−glycine mixtures were reacted at 250 °C and 10 MPa in an excess of water; both glucose and glycine were found to strongly influence the destruction kinetics of the other species and to result in quantitative and qualitative changes, such as strong absorbance at 420 nm and the production of a dark brown appearance and nutty odor, which are characteristic of the Maillard reaction. The presence of glucose always resulted in higher glycine destruction; the presence of glycine resulted in increased or decreased glucose destruction, depending on initial concentrations, which is consistent with results reported in the literature for lower temperature Maillard reactions. Surrogate compounds that contain the same chemical functional groups also resulted in similar trends. As a result of this reaction, the presence of proteins and amino acids in biomass feedstocks can be expected to result in processing difficulties at hydrothermal conditions: these difficulties will include fouling of process equipment, the quenching of desired reaction pathways, and difficulty in achieving separations between aqueous and oil phases produced. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014809

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Biodiesel synthesis by simultaneous esterification and transesterification using oleophilic acid catalyst / Yi-Shen Lien in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2118–2121 Titre : Biodiesel synthesis by simultaneous esterification and transesterification using oleophilic acid catalyst Type de document : texte imprimé Auteurs : Yi-Shen Lien, Auteur ; Li-Shan Hsieh, Auteur ; Jeffrey C. S. Wu, Auteur Année de publication : 2010 Article en page(s) : pp. 2118–2121 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Biodiesel  Esterification  Transesterification  Oleophilic  Solid-acid catalysts Résumé : Solid-acid catalysts can perform transesterification and esterification simultaneously so that free fatty acids (FFAs) in oil can be converted into biodiesel to avoid the disposal of biomaterial. A carbon catalyst was prepared by pyrolyzing glucose at 400 °C under a N2 stream. The catalyst was further sulfated using concentrated sulfuric acid. Transesterification of soybean oil and methanol was carried out at 150 °C and 1.7 MPa in a pressurized autoclave. More than 90% biodiesel yield was achieved within 2 h with a molar ratio of methanol to soybean oil of 30:1. The total biodiesel yield for the mixture of soybean oil and palmitic acid decreased to 85% when 20 wt % palmitic acid was used. A rate equation based on the Langmuir−Hishelwood mechanism was established to describe the kinetic behavior of transesterification. The adsorption equilibrium constant of soybean oil was higher than those of the other species, implying an oleophilic surface of the sulfated carbon catalyst. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901496h [article] Biodiesel synthesis by simultaneous esterification and transesterification using oleophilic acid catalyst [texte imprimé] / Yi-Shen Lien, Auteur ; Li-Shan Hsieh, Auteur ; Jeffrey C. S. Wu, Auteur . - 2010 . - pp. 2118–2121. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2118–2121 Mots-clés : Biodiesel  Esterification  Transesterification  Oleophilic  Solid-acid catalysts Résumé : Solid-acid catalysts can perform transesterification and esterification simultaneously so that free fatty acids (FFAs) in oil can be converted into biodiesel to avoid the disposal of biomaterial. A carbon catalyst was prepared by pyrolyzing glucose at 400 °C under a N2 stream. The catalyst was further sulfated using concentrated sulfuric acid. Transesterification of soybean oil and methanol was carried out at 150 °C and 1.7 MPa in a pressurized autoclave. More than 90% biodiesel yield was achieved within 2 h with a molar ratio of methanol to soybean oil of 30:1. The total biodiesel yield for the mixture of soybean oil and palmitic acid decreased to 85% when 20 wt % palmitic acid was used. A rate equation based on the Langmuir−Hishelwood mechanism was established to describe the kinetic behavior of transesterification. The adsorption equilibrium constant of soybean oil was higher than those of the other species, implying an oleophilic surface of the sulfated carbon catalyst. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901496h

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Instantaneous and overall indicators for determination of bottleneck ranking in metabolic reaction networks / Kansuporn Sriyudthsak in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2122–2129 Titre : Instantaneous and overall indicators for determination of bottleneck ranking in metabolic reaction networks Type de document : texte imprimé Auteurs : Kansuporn Sriyudthsak, Auteur ; Fumihide Shiraishi, Auteur Année de publication : 2010 Article en page(s) : pp. 2122–2129 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Metabolic Reaction Networks Résumé : A dynamic logarithmic gain expresses the percentage change in a dependent variable or metabolite concentration in response to an infinitesimal percentage change in an independent variable or enzyme activity. This article discusses the usefulness of several bottleneck ranking (BR) indicators that are functions of the logarithmic gain, to determine the most likely bottleneck enzyme in a dynamic metabolic reaction system. Mathematical models for penicillin V and ethanol fermentations are considered as case studies. The calculated results reveal that the instantaneous BR indicator, which is a product of the dynamic logarithmic gain and the metabolite concentration, is an effective measure for instantaneous bottleneck enzyme ranking changed during the fermentation period, whereas the overall BR indicator, which is a time-averaged value of the instantaneous BR indicator, is an effective measure for bottleneck enzyme ranking throughout the entire fermentation period. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901531d [article] Instantaneous and overall indicators for determination of bottleneck ranking in metabolic reaction networks [texte imprimé] / Kansuporn Sriyudthsak, Auteur ; Fumihide Shiraishi, Auteur . - 2010 . - pp. 2122–2129. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2122–2129 Mots-clés : Metabolic Reaction Networks Résumé : A dynamic logarithmic gain expresses the percentage change in a dependent variable or metabolite concentration in response to an infinitesimal percentage change in an independent variable or enzyme activity. This article discusses the usefulness of several bottleneck ranking (BR) indicators that are functions of the logarithmic gain, to determine the most likely bottleneck enzyme in a dynamic metabolic reaction system. Mathematical models for penicillin V and ethanol fermentations are considered as case studies. The calculated results reveal that the instantaneous BR indicator, which is a product of the dynamic logarithmic gain and the metabolite concentration, is an effective measure for instantaneous bottleneck enzyme ranking changed during the fermentation period, whereas the overall BR indicator, which is a time-averaged value of the instantaneous BR indicator, is an effective measure for bottleneck enzyme ranking throughout the entire fermentation period. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901531d

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Steady-state multiplicity in catalytic microcombustors / Almerinda Di Benedetto in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2130–2134 Titre : Steady-state multiplicity in catalytic microcombustors Type de document : texte imprimé Auteurs : Almerinda Di Benedetto, Auteur ; Valeria Di Sarli, Auteur Année de publication : 2010 Article en page(s) : pp. 2130–2134 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Catalytic microcombustors Résumé : In this work, two-dimensional computational fluid dynamics (CFD) simulations were run to investigate the possibility of a link between the initial conditions and the occurrence of blowout for a parallel-plate catalytic microcombustor. The results show that steady-state multiplicity occurs: Depending on the initial conditions, the range of inlet gas velocities at which stable operation is attained can be enlarged to avoid blowout. It is concluded that investigations into the thermal behavior of catalytic microcombustors have to deal with appropriate and aware choices of the initial conditions. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901615d [article] Steady-state multiplicity in catalytic microcombustors [texte imprimé] / Almerinda Di Benedetto, Auteur ; Valeria Di Sarli, Auteur . - 2010 . - pp. 2130–2134. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2130–2134 Mots-clés : Catalytic microcombustors Résumé : In this work, two-dimensional computational fluid dynamics (CFD) simulations were run to investigate the possibility of a link between the initial conditions and the occurrence of blowout for a parallel-plate catalytic microcombustor. The results show that steady-state multiplicity occurs: Depending on the initial conditions, the range of inlet gas velocities at which stable operation is attained can be enlarged to avoid blowout. It is concluded that investigations into the thermal behavior of catalytic microcombustors have to deal with appropriate and aware choices of the initial conditions. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901615d

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Novel synthesis techniques for preparation of ultrahigh-crystalline vanadyl pyrophosphate as a highly selective catalyst for n-butane oxidation / Ali A. Rownaghi in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2135–2143 Titre : Novel synthesis techniques for preparation of ultrahigh-crystalline vanadyl pyrophosphate as a highly selective catalyst for n-butane oxidation Type de document : texte imprimé Auteurs : Ali A. Rownaghi, Auteur ; Yun Hin Taufiq-Yap, Auteur Année de publication : 2010 Article en page(s) : pp. 2135–2143 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Vanady pyrophosphate catalyst  VPO  Solvothermal Résumé : The vanadyl hydrogen phosphate hemihydrate (VOHPO4·0.5H2O), with well-defined crystal size, has been successfully synthesized for the first time, using a simple one-step solvothermal process that was free of surfactants and water and had a short reaction time and low temperature. The synthesis was performed via the reaction of V2O5 and H3PO4 with an aliphatic alcohol (1-propanol or 1-butanol) at high temperatures (373, 393, and 423 K) in a high-pressure autoclave. The mixture of reactions directly gave the VOHPO4·0.5H2O, which is a valuable commercial catalyst precursor for the selective oxidation of n-butane to maleic anhydride. The catalyst precursors were dried by microwave irradiation. The reaction conditions (by varying the reducing agent and reaction temperature) were used further for optimization of the crystallite size, surface area, morphology, and activity of the nanostructure of vanadium phosphate oxide [(VO)2P2O7] catalyst. This new method significantly reduced the preparation time and lowered the production temperature (50%) of catalyst precursor (VOHPO4·0.5H2O), when compared to conventional hydrothermal synthesis methods. The as-prepared (VO)2P2O7 catalyst under various conditions exhibited remarkably different physical and chemical properties, indicating the potential of the suggested method in tuning the crystalline structure and surface area of (VO)2P2O7 to improve its catalytic performance. It was found that the length of the carbon chain in an alcohol and reaction temperature in the solvothermal condition had a great impact on the chemical and physical properties of resulting catalysts. Interestingly, there was no trace of VO(H2PO4)2, which is an impurity noted to be readily formed under solvothermal preparation conditions. The precursors and catalysts were characterized using a combination of powder X-ray diffraction (XRD), Brunauer−Emmett−Teller (BET) surface area measurement, scanning electron microscopy (SEM), and temperature-programmed reduction in hydrogen (H2-TPR). A correlation between the surface area of the catalyst and the activity was observed. Finally, the yield of maleic anhydride was significantly increased from 21% for conventional catalyst to 38% for the new solvothermal catalyst. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie902011a [article] Novel synthesis techniques for preparation of ultrahigh-crystalline vanadyl pyrophosphate as a highly selective catalyst for n-butane oxidation [texte imprimé] / Ali A. Rownaghi, Auteur ; Yun Hin Taufiq-Yap, Auteur . - 2010 . - pp. 2135–2143. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2135–2143 Mots-clés : Vanady pyrophosphate catalyst  VPO  Solvothermal Résumé : The vanadyl hydrogen phosphate hemihydrate (VOHPO4·0.5H2O), with well-defined crystal size, has been successfully synthesized for the first time, using a simple one-step solvothermal process that was free of surfactants and water and had a short reaction time and low temperature. The synthesis was performed via the reaction of V2O5 and H3PO4 with an aliphatic alcohol (1-propanol or 1-butanol) at high temperatures (373, 393, and 423 K) in a high-pressure autoclave. The mixture of reactions directly gave the VOHPO4·0.5H2O, which is a valuable commercial catalyst precursor for the selective oxidation of n-butane to maleic anhydride. The catalyst precursors were dried by microwave irradiation. The reaction conditions (by varying the reducing agent and reaction temperature) were used further for optimization of the crystallite size, surface area, morphology, and activity of the nanostructure of vanadium phosphate oxide [(VO)2P2O7] catalyst. This new method significantly reduced the preparation time and lowered the production temperature (50%) of catalyst precursor (VOHPO4·0.5H2O), when compared to conventional hydrothermal synthesis methods. The as-prepared (VO)2P2O7 catalyst under various conditions exhibited remarkably different physical and chemical properties, indicating the potential of the suggested method in tuning the crystalline structure and surface area of (VO)2P2O7 to improve its catalytic performance. It was found that the length of the carbon chain in an alcohol and reaction temperature in the solvothermal condition had a great impact on the chemical and physical properties of resulting catalysts. Interestingly, there was no trace of VO(H2PO4)2, which is an impurity noted to be readily formed under solvothermal preparation conditions. The precursors and catalysts were characterized using a combination of powder X-ray diffraction (XRD), Brunauer−Emmett−Teller (BET) surface area measurement, scanning electron microscopy (SEM), and temperature-programmed reduction in hydrogen (H2-TPR). A correlation between the surface area of the catalyst and the activity was observed. Finally, the yield of maleic anhydride was significantly increased from 21% for conventional catalyst to 38% for the new solvothermal catalyst. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie902011a

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Specific permeability of wood to water part 1 / Juha-Pekka Pokki in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2144–2154 Titre : Specific permeability of wood to water part 1 : longitudinal specific permeability of steamed, impregnated, and kraft-cooked wood Type de document : texte imprimé Auteurs : Juha-Pekka Pokki, Auteur ; Ville V. Laakso, Auteur ; Panu Tikka, Auteur Année de publication : 2010 Article en page(s) : pp. 2144–2154 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Permeability of wood to water Résumé : Two apparatuses for measuring the specific permeability of wood specimens are presented. The developed method was used to measure specific permeability to water in the longitudinal direction (of the log) for three wood species, pine (Pinus sylvestris), birch (Betula pendula), and eucalyptus (Eucalyptus grandis). The wood species were cooked to a certain degree under kraft cooking conditions. The effect of pretreatments on the specific permeability of uncooked wood was also studied. These pretreatments include boiling in water, steaming, and impregnation with cooking liquor. Wood species were cooked to a certain degree with an H factor of up to 600 for pine, 376 for birch, and 400 for eucalyptus. The average specific permeabilities to water ranged from 1 × 10−13 to 3 × 10−12 m3/m for cooked pine, from 1 × 10−13 to 1 × 10−12 m3/m for cooked birch, and from 3 × 10−11 to 5 × 10−11 m3/m for cooked eucalyptus. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801901f [article] Specific permeability of wood to water part 1 : longitudinal specific permeability of steamed, impregnated, and kraft-cooked wood [texte imprimé] / Juha-Pekka Pokki, Auteur ; Ville V. Laakso, Auteur ; Panu Tikka, Auteur . - 2010 . - pp. 2144–2154. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2144–2154 Mots-clés : Permeability of wood to water Résumé : Two apparatuses for measuring the specific permeability of wood specimens are presented. The developed method was used to measure specific permeability to water in the longitudinal direction (of the log) for three wood species, pine (Pinus sylvestris), birch (Betula pendula), and eucalyptus (Eucalyptus grandis). The wood species were cooked to a certain degree under kraft cooking conditions. The effect of pretreatments on the specific permeability of uncooked wood was also studied. These pretreatments include boiling in water, steaming, and impregnation with cooking liquor. Wood species were cooked to a certain degree with an H factor of up to 600 for pine, 376 for birch, and 400 for eucalyptus. The average specific permeabilities to water ranged from 1 × 10−13 to 3 × 10−12 m3/m for cooked pine, from 1 × 10−13 to 1 × 10−12 m3/m for cooked birch, and from 3 × 10−11 to 5 × 10−11 m3/m for cooked eucalyptus. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801901f

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Specific permeability of wood to water part 2 / Juha-Pekka Pokki in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2155–2160 Titre : Specific permeability of wood to water part 2 : perpendicular specific permeability of steamed, impregnated, and kraft-cooked wood Type de document : texte imprimé Auteurs : Juha-Pekka Pokki, Auteur ; Ville V. Laakso, Auteur ; Panu Tikka, Auteur Année de publication : 2010 Article en page(s) : pp. 2155–2160 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Permeability of wood to water Résumé : A method for measuring the perpendicular specific permeability of wood specimens to water is presented, which is a modification of the method presented in part 1 of this work. The specific permeability in the perpendicular direction of the log of three wood species, pine (Pinus sylvestris), birch (Betula pendula), and eucalyptus (Eucalyptus grandis), was measured from kraft-cooked wood of different cooking degrees. The effect of various forms of pretreatment on the specific permeability of uncooked wood to water was also studied, including steaming with and without cooking liquor impregnation and boiling in water. Wood pieces were cooked to a certain degree with an H factor of up to 600 for pine, up to 300 for birch, and up to 250 for eucalyptus. The average specific permeability of cooked pine ranged from 2 × 10−15 to 3.5 × 10−14 m3/m, that of cooked birch ranged from 1.7 × 10−15 to 8 × 10−14 m3/m, and that of cooked eucalyptus ranged from 2 × 10−15 to 3.5 × 10−14 m3/m. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801902b [article] Specific permeability of wood to water part 2 : perpendicular specific permeability of steamed, impregnated, and kraft-cooked wood [texte imprimé] / Juha-Pekka Pokki, Auteur ; Ville V. Laakso, Auteur ; Panu Tikka, Auteur . - 2010 . - pp. 2155–2160. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2155–2160 Mots-clés : Permeability of wood to water Résumé : A method for measuring the perpendicular specific permeability of wood specimens to water is presented, which is a modification of the method presented in part 1 of this work. The specific permeability in the perpendicular direction of the log of three wood species, pine (Pinus sylvestris), birch (Betula pendula), and eucalyptus (Eucalyptus grandis), was measured from kraft-cooked wood of different cooking degrees. The effect of various forms of pretreatment on the specific permeability of uncooked wood to water was also studied, including steaming with and without cooking liquor impregnation and boiling in water. Wood pieces were cooked to a certain degree with an H factor of up to 600 for pine, up to 300 for birch, and up to 250 for eucalyptus. The average specific permeability of cooked pine ranged from 2 × 10−15 to 3.5 × 10−14 m3/m, that of cooked birch ranged from 1.7 × 10−15 to 8 × 10−14 m3/m, and that of cooked eucalyptus ranged from 2 × 10−15 to 3.5 × 10−14 m3/m. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801902b

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Enzyme-assisted preparation of fibrillated cellulose fibers and Its effect on physical and mechanical properties of paper sheet composites / Sukjoon Yoo in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2161–2168 Titre : Enzyme-assisted preparation of fibrillated cellulose fibers and Its effect on physical and mechanical properties of paper sheet composites Type de document : texte imprimé Auteurs : Sukjoon Yoo, Auteur ; Jeffery S. Hsieh, Auteur Année de publication : 2010 Article en page(s) : pp. 2161–2168 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Cellulose Fibers Résumé : The fabrication of fibrillated cellulose fibers and their utilization have been of more interest recently because of their biodegradability, low cost, and mechanical and thermal properties comparable to those of glass fibers or carbon fibers. In this study, we applied the combination of a mechanical shearing process with a cooling system and an enzymatic pretreatment to produce fibrillated cellulose fibers from softwood pulps. The effects of the mechanical shearing process, the cooling system, and the enzymatic treatment on the formation of the fibrillated cellulose fibers as well as physical and mechanical properties of paper were investigated. It was indicated that the cooling system was necessary in the grinding process to prevent the adverse effect of heat generation on mechanical properties of paper sheets. It was observed that the enzyme-assisted mechanical shearing process improves the production of fibrillated cellulose fibers and results in a substantial improvement of tensile strength and elongation of paper while producing thinner and less bright paper with low water absorptiveness. Note de contenu : Bibliogr ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901621n [article] Enzyme-assisted preparation of fibrillated cellulose fibers and Its effect on physical and mechanical properties of paper sheet composites [texte imprimé] / Sukjoon Yoo, Auteur ; Jeffery S. Hsieh, Auteur . - 2010 . - pp. 2161–2168. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2161–2168 Mots-clés : Cellulose Fibers Résumé : The fabrication of fibrillated cellulose fibers and their utilization have been of more interest recently because of their biodegradability, low cost, and mechanical and thermal properties comparable to those of glass fibers or carbon fibers. In this study, we applied the combination of a mechanical shearing process with a cooling system and an enzymatic pretreatment to produce fibrillated cellulose fibers from softwood pulps. The effects of the mechanical shearing process, the cooling system, and the enzymatic treatment on the formation of the fibrillated cellulose fibers as well as physical and mechanical properties of paper were investigated. It was indicated that the cooling system was necessary in the grinding process to prevent the adverse effect of heat generation on mechanical properties of paper sheets. It was observed that the enzyme-assisted mechanical shearing process improves the production of fibrillated cellulose fibers and results in a substantial improvement of tensile strength and elongation of paper while producing thinner and less bright paper with low water absorptiveness. Note de contenu : Bibliogr ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901621n

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Influence of surface chemical composition on UV-varnish absorption into permeable pigment-coated paper / Maiju Pykönen in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2169–2175 Titre : Influence of surface chemical composition on UV-varnish absorption into permeable pigment-coated paper Type de document : texte imprimé Auteurs : Maiju Pykönen, Auteur ; Kenth Johansson, Auteur ; Roger Bollstrom, Auteur Année de publication : 2010 Article en page(s) : pp. 2169–2175 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Chemical composition  UV-Varnish  Permeable  Hydrocarbon plasma Résumé : Fluorocarbon, organosilicon, and hydrocarbon plasma coatings were used to modify the surface of permeable pigment-coated paper, and their impact on UV-varnish absorption was investigated. According to mercury porosimetry results, the plasma coatings had no influence on the porous structure of the paper. X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) results showed characteristic surface chemical compositions for each plasma coating. The fluorocarbon plasma coating increased the UV-varnish contact angles significantly, whereas the hydrocarbon plasma coating had no clear influence. When the UV varnish was applied with a flexography unit including nip pressure, the role of surface chemical composition seemed to become minimal. The viscosity of the UV varnish was shown to impact the absorption rate with and without external pressure. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900992t [article] Influence of surface chemical composition on UV-varnish absorption into permeable pigment-coated paper [texte imprimé] / Maiju Pykönen, Auteur ; Kenth Johansson, Auteur ; Roger Bollstrom, Auteur . - 2010 . - pp. 2169–2175. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2169–2175 Mots-clés : Chemical composition  UV-Varnish  Permeable  Hydrocarbon plasma Résumé : Fluorocarbon, organosilicon, and hydrocarbon plasma coatings were used to modify the surface of permeable pigment-coated paper, and their impact on UV-varnish absorption was investigated. According to mercury porosimetry results, the plasma coatings had no influence on the porous structure of the paper. X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) results showed characteristic surface chemical compositions for each plasma coating. The fluorocarbon plasma coating increased the UV-varnish contact angles significantly, whereas the hydrocarbon plasma coating had no clear influence. When the UV varnish was applied with a flexography unit including nip pressure, the role of surface chemical composition seemed to become minimal. The viscosity of the UV varnish was shown to impact the absorption rate with and without external pressure. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900992t

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Preparation and characterization of cross-linked starch/poly(vinyl alcohol) green films with low moisture absorption / Kunal Das in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2176–2185 Titre : Preparation and characterization of cross-linked starch/poly(vinyl alcohol) green films with low moisture absorption Type de document : texte imprimé Auteurs : Kunal Das, Auteur ; Dipa Ray, Auteur ; N. R. Bandyopadhyay, Auteur Année de publication : 2010 Article en page(s) : pp. 2176–2185 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Starch/poly(vinyl alcohol)  TGA Résumé : The effects of incorporating different cross-linking agents into starch/poly(vinyl alcohol) (PVA) blend were examined by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), mechanical characterization, dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), moisture absorption tests, and scanning electron microscopy (SEM). Different cross-linkers such as borax, formaldehyde, epichlorohydrin, and ZnO were used to cross-link the films at the same weight percent. The films were prepared by gelatinization followed by a solution casting method. SEM microstructures revealed that the destructuring of starch granules was significantly influenced by the presence of cross-linkers during the gelatinization process. The extent of cross-linking was measured through the determination of the normalized gel mass and the normalized swelling degree of the films in dimethyl sulfoxide (DMSO) solvent. Tensile strength and tensile modulus were highest in borax cross-linked film, while the highest flexibility was achieved with the epichlorohydrin cross-linked film. Damping was remarkably increased, and moisture absorption was considerably decreased in the cross-linked films. The onset of thermal degradation was lowered, but the char yield was slightly increased in the cross-linked films. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901092n [article] Preparation and characterization of cross-linked starch/poly(vinyl alcohol) green films with low moisture absorption [texte imprimé] / Kunal Das, Auteur ; Dipa Ray, Auteur ; N. R. Bandyopadhyay, Auteur . - 2010 . - pp. 2176–2185. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2176–2185 Mots-clés : Starch/poly(vinyl alcohol)  TGA Résumé : The effects of incorporating different cross-linking agents into starch/poly(vinyl alcohol) (PVA) blend were examined by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), mechanical characterization, dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), moisture absorption tests, and scanning electron microscopy (SEM). Different cross-linkers such as borax, formaldehyde, epichlorohydrin, and ZnO were used to cross-link the films at the same weight percent. The films were prepared by gelatinization followed by a solution casting method. SEM microstructures revealed that the destructuring of starch granules was significantly influenced by the presence of cross-linkers during the gelatinization process. The extent of cross-linking was measured through the determination of the normalized gel mass and the normalized swelling degree of the films in dimethyl sulfoxide (DMSO) solvent. Tensile strength and tensile modulus were highest in borax cross-linked film, while the highest flexibility was achieved with the epichlorohydrin cross-linked film. Damping was remarkably increased, and moisture absorption was considerably decreased in the cross-linked films. The onset of thermal degradation was lowered, but the char yield was slightly increased in the cross-linked films. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901092n

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Study of cell nucleation in microcellular poly(lactic acid) foamed with supercritical CO2 through a continuous-extrusion process / Laurent M. Matuana in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2186–2193 Titre : Study of cell nucleation in microcellular poly(lactic acid) foamed with supercritical CO2 through a continuous-extrusion process Type de document : texte imprimé Auteurs : Laurent M. Matuana, Auteur ; Carlos A. Diaz, Auteur Année de publication : 2010 Article en page(s) : pp. 2186–2193 Note générale : Industial Chemistry Langues : Anglais (eng) Mots-clés : Nucleation  Poly(lactic acid) Résumé : Using a continuous-extrusion foaming process, this study examined the effect of the processing temperature on the melt viscosity, pressure drop rate, and cell-population density of poly(lactic acid) (PLA) foams. The study was intended to understand the nucleation mechanisms in order to generate microcellular structures in neat PLA in a continuous-extrusion process using CO2 as the blowing agent. Not only did the temperature affect the melt viscosity but also the cell nucleation rate owing to its effect on the pressure drop rate. When processed at high temperature, the melt viscosity decreased and PLA nucleated fewer bubbles, irrespective of the PLA type (amorphous vs semicrystalline), because of the lower pressure drop rate in the system. Conversely, processing at a lower temperature significantly increased the cell nucleation rate for both PLA types owing to the fact that a high melt viscosity induced a high pressure drop rate. The addition of nanoclay allowed both homogeneous and heterogeneous nucleation to occur during the foaming process. The results showed that the processing temperature is a sensible parameter to produce microcellular PLA with cell densities on the order of 109 cells/cm3 and cell sizes of around 10 μm. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9011694 [article] Study of cell nucleation in microcellular poly(lactic acid) foamed with supercritical CO2 through a continuous-extrusion process [texte imprimé] / Laurent M. Matuana, Auteur ; Carlos A. Diaz, Auteur . - 2010 . - pp. 2186–2193. Industial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2186–2193 Mots-clés : Nucleation  Poly(lactic acid) Résumé : Using a continuous-extrusion foaming process, this study examined the effect of the processing temperature on the melt viscosity, pressure drop rate, and cell-population density of poly(lactic acid) (PLA) foams. The study was intended to understand the nucleation mechanisms in order to generate microcellular structures in neat PLA in a continuous-extrusion process using CO2 as the blowing agent. Not only did the temperature affect the melt viscosity but also the cell nucleation rate owing to its effect on the pressure drop rate. When processed at high temperature, the melt viscosity decreased and PLA nucleated fewer bubbles, irrespective of the PLA type (amorphous vs semicrystalline), because of the lower pressure drop rate in the system. Conversely, processing at a lower temperature significantly increased the cell nucleation rate for both PLA types owing to the fact that a high melt viscosity induced a high pressure drop rate. The addition of nanoclay allowed both homogeneous and heterogeneous nucleation to occur during the foaming process. The results showed that the processing temperature is a sensible parameter to produce microcellular PLA with cell densities on the order of 109 cells/cm3 and cell sizes of around 10 μm. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9011694

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Characterization of Ti-ZSM-5 prepared by isomorphous substitution of B-ZSM-5 with TiCl4 and its performance in the hydroxylation of phenol / Jian Gao in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2194–2199 Titre : Characterization of Ti-ZSM-5 prepared by isomorphous substitution of B-ZSM-5 with TiCl4 and its performance in the hydroxylation of phenol Type de document : texte imprimé Auteurs : Jian Gao, Auteur ; Liu, Min, Auteur ; Xiangsheng Wang, Auteur Année de publication : 2010 Article en page(s) : pp. 2194–2199 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Ti-ZSM-5  B-ZSM-5  Isomorphous substitution Résumé : Ti-ZSM-5 has attracted much attention for its unique catalytic properties in selective oxidation. Isomorphous substitution is an alternative synthesis method to obtain Ti-ZSM-5 with low contents of extraframework Ti. However, the nature of the precursor also has a great influence on the catalytic performance of Ti-ZSM-5. In this work, two Ti-ZSM-5 samples were prepared by isomorphous substitution of precursor B-ZSM-5 zeolites with gaseous TiCl4. The effect of the nature of the B-ZSM-5 precursor obtained by different hydrothermal synthesis procedures on the catalytic performance was investigated through characterization by XRD; FT-IR, UV−vis, and UV−Raman spectroscopies; SEM; N2 adsorption; and phenol hydroxylation. The characterization results show that the two Ti-ZSM-5 samples synthesized by gas−solid isomorphous substitution of the B-ZSM-5 precursor contain very little anatase and have similar amounts of active sites. They consist of cuboidlike crystals with different sizes that are agglomerated into different sizes of spherelike particles. Phenol hydroxylation with dilute H2O2 showed that, because of the smaller crystal size of its cuboid particles, Ti-ZSM-5 synthesized with B-ZSM-5 as the precursor at lower crystallization temperature had better catalytic performance and better recyclability. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901360y [article] Characterization of Ti-ZSM-5 prepared by isomorphous substitution of B-ZSM-5 with TiCl4 and its performance in the hydroxylation of phenol [texte imprimé] / Jian Gao, Auteur ; Liu, Min, Auteur ; Xiangsheng Wang, Auteur . - 2010 . - pp. 2194–2199. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2194–2199 Mots-clés : Ti-ZSM-5  B-ZSM-5  Isomorphous substitution Résumé : Ti-ZSM-5 has attracted much attention for its unique catalytic properties in selective oxidation. Isomorphous substitution is an alternative synthesis method to obtain Ti-ZSM-5 with low contents of extraframework Ti. However, the nature of the precursor also has a great influence on the catalytic performance of Ti-ZSM-5. In this work, two Ti-ZSM-5 samples were prepared by isomorphous substitution of precursor B-ZSM-5 zeolites with gaseous TiCl4. The effect of the nature of the B-ZSM-5 precursor obtained by different hydrothermal synthesis procedures on the catalytic performance was investigated through characterization by XRD; FT-IR, UV−vis, and UV−Raman spectroscopies; SEM; N2 adsorption; and phenol hydroxylation. The characterization results show that the two Ti-ZSM-5 samples synthesized by gas−solid isomorphous substitution of the B-ZSM-5 precursor contain very little anatase and have similar amounts of active sites. They consist of cuboidlike crystals with different sizes that are agglomerated into different sizes of spherelike particles. Phenol hydroxylation with dilute H2O2 showed that, because of the smaller crystal size of its cuboid particles, Ti-ZSM-5 synthesized with B-ZSM-5 as the precursor at lower crystallization temperature had better catalytic performance and better recyclability. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901360y

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Sonochemical synthesis of ZnO encapsulated functional nanolatex and its anticorrosive performance / Shirish H. Sonawane in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2200–2205 Titre : Sonochemical synthesis of ZnO encapsulated functional nanolatex and its anticorrosive performance Type de document : texte imprimé Auteurs : Shirish H. Sonawane, Auteur ; Boon M. Teo, Auteur ; Adam Brotchie, Auteur Année de publication : 2010 Article en page(s) : pp. 2200–2205 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : ZnO  Sonochemical synthesis  Poly(butyl methacrylate)  Corrosion Résumé : ZnO/poly(butyl methacrylate) (PBMA) and ZnO−PBMA/polyaniline (PANI) nanolatex composite particles of 50 nm were synthesized by a hydrothermal−sonochemical emulsion polymerization technique. The anticorrosive performance of the synthesized latex was evaluated on a steel substrate. The anticorrosive performance was compared for acid/salt/alkali induced corrosion. It was found that the performance of the ZnO−PBMA coating for acid corrosion was superior to that of the ZnO−PBMA−PANI matrix. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015039 [article] Sonochemical synthesis of ZnO encapsulated functional nanolatex and its anticorrosive performance [texte imprimé] / Shirish H. Sonawane, Auteur ; Boon M. Teo, Auteur ; Adam Brotchie, Auteur . - 2010 . - pp. 2200–2205. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2200–2205 Mots-clés : ZnO  Sonochemical synthesis  Poly(butyl methacrylate)  Corrosion Résumé : ZnO/poly(butyl methacrylate) (PBMA) and ZnO−PBMA/polyaniline (PANI) nanolatex composite particles of 50 nm were synthesized by a hydrothermal−sonochemical emulsion polymerization technique. The anticorrosive performance of the synthesized latex was evaluated on a steel substrate. The anticorrosive performance was compared for acid/salt/alkali induced corrosion. It was found that the performance of the ZnO−PBMA coating for acid corrosion was superior to that of the ZnO−PBMA−PANI matrix. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015039

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PH effects on the synthesis of nanocapsules via interfacial miniemulsion polymerization mediated by amphiphilic RAFT agent with the R group of poly(methyl acrylic acid-ran-styrene) / Fujun Lu in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2206–2212 Titre : PH effects on the synthesis of nanocapsules via interfacial miniemulsion polymerization mediated by amphiphilic RAFT agent with the R group of poly(methyl acrylic acid-ran-styrene) Type de document : texte imprimé Auteurs : Fujun Lu, Auteur ; Yingwu Luo, Auteur ; Bogeng Li, Auteur Année de publication : 2010 Article en page(s) : pp. 2206–2212 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Nanocapsules  Poly(methyl acrylic acid-co-styrene)  RAFT  Polymerization Résumé : Interfacial radical miniemulsion polymerization was constructed to be a general process for nanoencapsulation and the preparation of nanocapsules by using an amphiphilic reversible addition−fragmentation transfer (RAFT) agent with the R group of poly(methyl acrylic acid-co-styrene) as a reactive surfactant. Styrene and n-nonadecane were used as a model of monomer and core materials, respectively. It was found that the fragmental R radicals, which exited out of the droplets into the water phase, could trigger the homogeneous nucleation. When the homogeneous nucleation rather than the monomer droplet nucleation became the dominant mechanism of the particle formation, a large fraction of solid particles would be coformed with the nanocapsules. By decreasing pH values, we could decrease the hydrophilicity of R radicals and thus suppress the formation of the solid particles from the homogeneous nucleation. For the current model system, when values were decreased from pH 8.12 to 6.45, the fraction of nanocapsules linearly increased from 18 to 94%. In the middle pH values very uniform nanocapsules were obtained accompanying a few of the solid particles. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901515t [article] PH effects on the synthesis of nanocapsules via interfacial miniemulsion polymerization mediated by amphiphilic RAFT agent with the R group of poly(methyl acrylic acid-ran-styrene) [texte imprimé] / Fujun Lu, Auteur ; Yingwu Luo, Auteur ; Bogeng Li, Auteur . - 2010 . - pp. 2206–2212. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2206–2212 Mots-clés : Nanocapsules  Poly(methyl acrylic acid-co-styrene)  RAFT  Polymerization Résumé : Interfacial radical miniemulsion polymerization was constructed to be a general process for nanoencapsulation and the preparation of nanocapsules by using an amphiphilic reversible addition−fragmentation transfer (RAFT) agent with the R group of poly(methyl acrylic acid-co-styrene) as a reactive surfactant. Styrene and n-nonadecane were used as a model of monomer and core materials, respectively. It was found that the fragmental R radicals, which exited out of the droplets into the water phase, could trigger the homogeneous nucleation. When the homogeneous nucleation rather than the monomer droplet nucleation became the dominant mechanism of the particle formation, a large fraction of solid particles would be coformed with the nanocapsules. By decreasing pH values, we could decrease the hydrophilicity of R radicals and thus suppress the formation of the solid particles from the homogeneous nucleation. For the current model system, when values were decreased from pH 8.12 to 6.45, the fraction of nanocapsules linearly increased from 18 to 94%. In the middle pH values very uniform nanocapsules were obtained accompanying a few of the solid particles. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901515t

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Mechanochemical route for synthesizing KMgPO4 and NH4MgPO4 for application as slow-release fertilizers / Solihin in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2213–2216 Titre : Mechanochemical route for synthesizing KMgPO4 and NH4MgPO4 for application as slow-release fertilizers Type de document : texte imprimé Auteurs : Solihin, Auteur ; Qiwu Zhang, Auteur ; William Tongamp, Auteur Année de publication : 2010 Article en page(s) : pp. 2213–2216 Note générale : Indusrial Chemistry Langues : Anglais (eng) Mots-clés : Fertilizers  Mechanochemical synthesis Résumé : This article introduces a mechanochemical (MC) process for the synthesis of KMgPO4 and NH4MgPO4 by milling starting materials in a planetary ball mill. First, KMgPO4 was prepared by milling KHPO4 and Mg(OH)2 at a molar ratio of 1:1 for 120 min at mill rotational speeds of 500−600 rpm. Washing of KMgPO4 in water for 700 h released only up to 20−25% of K+ and PO42− ions into solution. Second, NH4MgPO4 was prepared by milling NH4HPO4 and Mg(OH)2 at a molar ratio of 1:1 for 120 min at mill rotational speeds of 300−700 rpm. Washing of NH4MgPO4 in water for 500 h released only up to 10−20% of NH4+ and PO42− ions into solution. The MC process could be developed to synthesize KMgPO4 and NH4MgPO4 for possible application as slow-release fertilizers. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901780v [article] Mechanochemical route for synthesizing KMgPO4 and NH4MgPO4 for application as slow-release fertilizers [texte imprimé] / Solihin, Auteur ; Qiwu Zhang, Auteur ; William Tongamp, Auteur . - 2010 . - pp. 2213–2216. Indusrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2213–2216 Mots-clés : Fertilizers  Mechanochemical synthesis Résumé : This article introduces a mechanochemical (MC) process for the synthesis of KMgPO4 and NH4MgPO4 by milling starting materials in a planetary ball mill. First, KMgPO4 was prepared by milling KHPO4 and Mg(OH)2 at a molar ratio of 1:1 for 120 min at mill rotational speeds of 500−600 rpm. Washing of KMgPO4 in water for 700 h released only up to 20−25% of K+ and PO42− ions into solution. Second, NH4MgPO4 was prepared by milling NH4HPO4 and Mg(OH)2 at a molar ratio of 1:1 for 120 min at mill rotational speeds of 300−700 rpm. Washing of NH4MgPO4 in water for 500 h released only up to 10−20% of NH4+ and PO42− ions into solution. The MC process could be developed to synthesize KMgPO4 and NH4MgPO4 for possible application as slow-release fertilizers. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901780v

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Polycarbonate/clay nanocomposites via in situ melt polycondensation / Mallikarjuna S. Rama in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2217–2227 Titre : Polycarbonate/clay nanocomposites via in situ melt polycondensation Type de document : texte imprimé Auteurs : Mallikarjuna S. Rama, Auteur ; Sivaram Swaminathan, Auteur Année de publication : 2010 Article en page(s) : pp. 2217–2227 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Polycarbonate/clay  Nanocomposites Résumé : Polycarbonate (PC)/clay nanocomposites were prepared via in situ melt polycondensation using novel organoclays modified using phosphonium and imidazolium based cations. The molecular weight of the separated polymer separated from the nanocomposites reveals that phosphonium ion modified organoclays catalyze the polycondensation of bisphenol A with diphenyl carbonate. Wide angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM) indicated that exfoliated polycarbonate/clay nanocomposites could be obtained using organoclays which have reactive bisphenol functionality in the modifier. The glass transition temperature (Tg) of the nanocomposites was studied using differential scanning calorimetry (DSC). The use of a more thermally stable modifier did not improve the color in polycarbonate clay nanocomposites. Although an approach to produce fully exfoliated PC nanocomposites are evident from this study, the process is far from perfect from the point of producing a color free transparent PC. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015649 [article] Polycarbonate/clay nanocomposites via in situ melt polycondensation [texte imprimé] / Mallikarjuna S. Rama, Auteur ; Sivaram Swaminathan, Auteur . - 2010 . - pp. 2217–2227. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2217–2227 Mots-clés : Polycarbonate/clay  Nanocomposites Résumé : Polycarbonate (PC)/clay nanocomposites were prepared via in situ melt polycondensation using novel organoclays modified using phosphonium and imidazolium based cations. The molecular weight of the separated polymer separated from the nanocomposites reveals that phosphonium ion modified organoclays catalyze the polycondensation of bisphenol A with diphenyl carbonate. Wide angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM) indicated that exfoliated polycarbonate/clay nanocomposites could be obtained using organoclays which have reactive bisphenol functionality in the modifier. The glass transition temperature (Tg) of the nanocomposites was studied using differential scanning calorimetry (DSC). The use of a more thermally stable modifier did not improve the color in polycarbonate clay nanocomposites. Although an approach to produce fully exfoliated PC nanocomposites are evident from this study, the process is far from perfect from the point of producing a color free transparent PC. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015649

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PCA-ARMA-based control charts for performance monitoring of multivariable feedback control / Junghui Chen in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2228–2241 Titre : PCA-ARMA-based control charts for performance monitoring of multivariable feedback control Type de document : texte imprimé Auteurs : Junghui Chen, Auteur ; Wei-Yann Wang, Auteur Année de publication : 2010 Article en page(s) : pp. 2228–2241 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Control systems  PCA- ARMA  Feedback Résumé : Assessing the effectiveness of control systems and limiting the incidence of fault events are main emphases of studies on performance assessment of control systems. In single-input/single-output (SISO) systems, the performance bounds are easily estimated from the minimum variance of a single variable; however, in multi-input/multi-output (MIMO) systems, the benchmark is computed from traces of multivariable covariance matrices. This MIMO method of performance assessment sometimes can cause false detection because it does not consider the correlation among variables. In this article, a new method, called PCA−ARMA-based performance assessment, is proposed. It is an integrated framework of multivariable principal component analysis (PCA) and the autoregressive moving average (ARMA) filter. It can build up the PCA-based minimum-variance performance bound of the MIMO feedback control system under minimum-variance control. In this integrated framework, the difference between the process outputs and the desired set points is projected onto the PCA space to determine the scores and residuals. An ARMA filter is selected to eliminate the autocorrelation of the scores. The independent scores and residuals are used to compute two statistics, which serve as performance indices in monitoring the progress of operation. Because MV control of processes is at times impractical or even infeasible, the integrated PCA and ARMA method, which is used to design achievable-minimum-variance (AMV) control, is proposed. AMV control is proposed to tune the controller parameters and minimize the weighted sum of variances of the various scores. Again, the multivariable PCA and the ARMA filter build up the AMV performance bound of the MIMO feedback control system under AMV control. The integrated method can result in better monitor indices. The performance of the proposed AMV method is illustrated through a simulation case and a quadruple-tank experiment. The case studies show that the proposed method yields better monitoring results than the conventional approaches in terms of sensitivity and response time to system degradation. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900561x [article] PCA-ARMA-based control charts for performance monitoring of multivariable feedback control [texte imprimé] / Junghui Chen, Auteur ; Wei-Yann Wang, Auteur . - 2010 . - pp. 2228–2241. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2228–2241 Mots-clés : Control systems  PCA- ARMA  Feedback Résumé : Assessing the effectiveness of control systems and limiting the incidence of fault events are main emphases of studies on performance assessment of control systems. In single-input/single-output (SISO) systems, the performance bounds are easily estimated from the minimum variance of a single variable; however, in multi-input/multi-output (MIMO) systems, the benchmark is computed from traces of multivariable covariance matrices. This MIMO method of performance assessment sometimes can cause false detection because it does not consider the correlation among variables. In this article, a new method, called PCA−ARMA-based performance assessment, is proposed. It is an integrated framework of multivariable principal component analysis (PCA) and the autoregressive moving average (ARMA) filter. It can build up the PCA-based minimum-variance performance bound of the MIMO feedback control system under minimum-variance control. In this integrated framework, the difference between the process outputs and the desired set points is projected onto the PCA space to determine the scores and residuals. An ARMA filter is selected to eliminate the autocorrelation of the scores. The independent scores and residuals are used to compute two statistics, which serve as performance indices in monitoring the progress of operation. Because MV control of processes is at times impractical or even infeasible, the integrated PCA and ARMA method, which is used to design achievable-minimum-variance (AMV) control, is proposed. AMV control is proposed to tune the controller parameters and minimize the weighted sum of variances of the various scores. Again, the multivariable PCA and the ARMA filter build up the AMV performance bound of the MIMO feedback control system under AMV control. The integrated method can result in better monitor indices. The performance of the proposed AMV method is illustrated through a simulation case and a quadruple-tank experiment. The case studies show that the proposed method yields better monitoring results than the conventional approaches in terms of sensitivity and response time to system degradation. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900561x

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Constrained nonlinear state estimation using ensemble kalman filters / J. Prakash in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2242–2253 Titre : Constrained nonlinear state estimation using ensemble kalman filters Type de document : texte imprimé Auteurs : J. Prakash, Auteur ; Sachin C. Patwardhan, Auteur ; Sirish L. Shah, Auteur Année de publication : 2010 Article en page(s) : pp. 2242–2253 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : EnKF  kalman Résumé : Recursive estimation of states of constrained nonlinear dynamic systems has attracted the attention of many researchers in recent years. In this work, we propose a constrained recursive formulation of the ensemble Kalman filter (EnKF) that retains the advantages of the unconstrained EnKF while systematically dealing with bounds on the estimated states. The EnKF belongs to the class of particle filters that are increasingly being used for solving state estimation problems associated with nonlinear systems. A highlight of our approach is the use of truncated multivariate distributions for systematically solving the estimation problem in the presence of state constraints. The efficacy of the proposed constrained state estimation algorithm using the EnKF is illustrated by application on two benchmark problems in the literature (a simulated gas-phase reactor and an isothermal batch reactor) involving constraints on estimated state variables and another example problem, which involves constraints on the process noise. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900197s [article] Constrained nonlinear state estimation using ensemble kalman filters [texte imprimé] / J. Prakash, Auteur ; Sachin C. Patwardhan, Auteur ; Sirish L. Shah, Auteur . - 2010 . - pp. 2242–2253. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2242–2253 Mots-clés : EnKF  kalman Résumé : Recursive estimation of states of constrained nonlinear dynamic systems has attracted the attention of many researchers in recent years. In this work, we propose a constrained recursive formulation of the ensemble Kalman filter (EnKF) that retains the advantages of the unconstrained EnKF while systematically dealing with bounds on the estimated states. The EnKF belongs to the class of particle filters that are increasingly being used for solving state estimation problems associated with nonlinear systems. A highlight of our approach is the use of truncated multivariate distributions for systematically solving the estimation problem in the presence of state constraints. The efficacy of the proposed constrained state estimation algorithm using the EnKF is illustrated by application on two benchmark problems in the literature (a simulated gas-phase reactor and an isothermal batch reactor) involving constraints on estimated state variables and another example problem, which involves constraints on the process noise. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900197s

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Adaptive kernel principal component analysis (KPCA) for monitoring small disturbances of nonlinear processes / Chun-Yuan Cheng in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2254–2262 Titre : Adaptive kernel principal component analysis (KPCA) for monitoring small disturbances of nonlinear processes Type de document : texte imprimé Auteurs : Chun-Yuan Cheng, Auteur ; Chun-Chin Hsu, Auteur ; Mu-Chen Chen, Auteur Année de publication : 2010 Article en page(s) : pp. 2254–2262 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : KPCA  Disturbances of Nonlinear  Multivariate  Monitoring Résumé : The Tennessee Eastman (TE) process, created by Eastman Chemical Company, is a complex nonlinear process. Many previous studies focus on the detectability of monitoring a multivariate process by using TE process as an example. Principal component analysis (PCA) is a widely used dimension-reduction tool for monitoring multivariate linear process. Recently, the kernel principal component analysis (KPCA) has emerged as an effective method to tackling the problem of nonlinear data. Nevertheless, the conventional KPCA used the sum of squares of latest observations as the monitoring statistics and hence failed to detect small disturbance of the process. To enhance the detectability of the KPCA-based monitoring method, an adaptive KPCA-based monitoring statistic is proposed in this paper. The basic idea of the proposed method is first adopting the multivariate exponentially moving average to predict the process mean shifts and then combining the estimated mean shifts with the extracted components by KPCA to construct the adaptive monitoring statistic. The efficiency of the proposed monitoring scheme is implemented in a simulated nonlinear system and in the TE process. The experimental results indicate that the proposed method outperforms the traditional PCA and KPCA monitoring schemes. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900521b [article] Adaptive kernel principal component analysis (KPCA) for monitoring small disturbances of nonlinear processes [texte imprimé] / Chun-Yuan Cheng, Auteur ; Chun-Chin Hsu, Auteur ; Mu-Chen Chen, Auteur . - 2010 . - pp. 2254–2262. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2254–2262 Mots-clés : KPCA  Disturbances of Nonlinear  Multivariate  Monitoring Résumé : The Tennessee Eastman (TE) process, created by Eastman Chemical Company, is a complex nonlinear process. Many previous studies focus on the detectability of monitoring a multivariate process by using TE process as an example. Principal component analysis (PCA) is a widely used dimension-reduction tool for monitoring multivariate linear process. Recently, the kernel principal component analysis (KPCA) has emerged as an effective method to tackling the problem of nonlinear data. Nevertheless, the conventional KPCA used the sum of squares of latest observations as the monitoring statistics and hence failed to detect small disturbance of the process. To enhance the detectability of the KPCA-based monitoring method, an adaptive KPCA-based monitoring statistic is proposed in this paper. The basic idea of the proposed method is first adopting the multivariate exponentially moving average to predict the process mean shifts and then combining the estimated mean shifts with the extracted components by KPCA to construct the adaptive monitoring statistic. The efficiency of the proposed monitoring scheme is implemented in a simulated nonlinear system and in the TE process. The experimental results indicate that the proposed method outperforms the traditional PCA and KPCA monitoring schemes. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900521b

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Using neural networks to address nonlinear pH control in wet limestone flue gas desulfurization plants / A. L. Villanueva Perales in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2263–2272 Titre : Using neural networks to address nonlinear pH control in wet limestone flue gas desulfurization plants Type de document : texte imprimé Auteurs : A. L. Villanueva Perales, Auteur ; F. J. Gutiérrez Ortiz, Auteur ; F. Vidal Barrero, Auteur Année de publication : 2010 Article en page(s) : pp. 2263–2272 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Neural networks  Nonlinear  Control strategies Résumé : In previous articles,(1-3) we evaluated the performance of different linear control strategies (decentralized feedback control and multivariable predictive control) in wet limestone flue gas desulfurization (WLFGD) plants based on a pilot plant study. Although these control strategies show good performance, they may not be suitable if the oxidation tank pH is significantly nonlinear, which depends on many plant operating factors. Control of oxidation tank pH is important since it is related to the quality of gypsum, a byproduct of the WLFGD process. In this work, we propose and assess a combined control strategy for dealing with nonlinear pH control in WLFGD plants, based on a decentralized strategy composed of a neural predictive controller and a feedback controller, which control the oxidation tank pH and SO2 concentration of the desulfurized gas, respectively. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9007584 [article] Using neural networks to address nonlinear pH control in wet limestone flue gas desulfurization plants [texte imprimé] / A. L. Villanueva Perales, Auteur ; F. J. Gutiérrez Ortiz, Auteur ; F. Vidal Barrero, Auteur . - 2010 . - pp. 2263–2272. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2263–2272 Mots-clés : Neural networks  Nonlinear  Control strategies Résumé : In previous articles,(1-3) we evaluated the performance of different linear control strategies (decentralized feedback control and multivariable predictive control) in wet limestone flue gas desulfurization (WLFGD) plants based on a pilot plant study. Although these control strategies show good performance, they may not be suitable if the oxidation tank pH is significantly nonlinear, which depends on many plant operating factors. Control of oxidation tank pH is important since it is related to the quality of gypsum, a byproduct of the WLFGD process. In this work, we propose and assess a combined control strategy for dealing with nonlinear pH control in WLFGD plants, based on a decentralized strategy composed of a neural predictive controller and a feedback controller, which control the oxidation tank pH and SO2 concentration of the desulfurized gas, respectively. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9007584

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Hybrid genetic programming−first-principles approach To process and product modeling / Kevin C. Seavey in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2273–2285 Titre : Hybrid genetic programming−first-principles approach To process and product modeling Type de document : texte imprimé Auteurs : Kevin C. Seavey, Auteur ; Adam T. Jones, Auteur ; Arthur K. Kordon, Auteur Année de publication : 2010 Article en page(s) : pp. 2273–2285 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Hybrid Genetic  Product Modeling  Empirical models  Nonlinear Conventional linear Polymer viscosity Résumé : In this study, we build hybrid fundamental and empirical models. The empirical models are either conventional linear models or nonlinear models derived using genetic programming (GP). This modeling technique is useful in multiscale modeling for constructing compact representations of experimental data or data generated using complex fundamental models. These representations, which can have tunable fundamental and empirical characteristics, allow us to efficiently leverage information between multiple scales and modeling platforms. We apply this technique to model vapor-liquid equilibrium (VLE) and polymer viscosity. Regarding our particular VLE data, our work indicates that although reasonably accurate models for the excess Gibbs energies can be built using linear models, the models themselves contain a large number of free parameters. The GP-generated models, on the other hand, use nonlinear equations and fewer parameters to capture the dependence of the excess Gibbs energies on temperature and mixture composition. Regarding the polymer viscosity data, good linear models can be easily constructed to capture the dependence of the Williams−Landel−Ferry equation residuals of the viscosity on the molecular characteristics of the polymers. However, the GP-generated nonlinear models are more compact and contain fewer parameters. All of the hybrid models shown here are simple to generate, accurate, and portable, meaning that they can be easily leveraged across a variety of modeling platforms Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900860y [article] Hybrid genetic programming−first-principles approach To process and product modeling [texte imprimé] / Kevin C. Seavey, Auteur ; Adam T. Jones, Auteur ; Arthur K. Kordon, Auteur . - 2010 . - pp. 2273–2285. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2273–2285 Mots-clés : Hybrid Genetic  Product Modeling  Empirical models  Nonlinear Conventional linear Polymer viscosity Résumé : In this study, we build hybrid fundamental and empirical models. The empirical models are either conventional linear models or nonlinear models derived using genetic programming (GP). This modeling technique is useful in multiscale modeling for constructing compact representations of experimental data or data generated using complex fundamental models. These representations, which can have tunable fundamental and empirical characteristics, allow us to efficiently leverage information between multiple scales and modeling platforms. We apply this technique to model vapor-liquid equilibrium (VLE) and polymer viscosity. Regarding our particular VLE data, our work indicates that although reasonably accurate models for the excess Gibbs energies can be built using linear models, the models themselves contain a large number of free parameters. The GP-generated models, on the other hand, use nonlinear equations and fewer parameters to capture the dependence of the excess Gibbs energies on temperature and mixture composition. Regarding the polymer viscosity data, good linear models can be easily constructed to capture the dependence of the Williams−Landel−Ferry equation residuals of the viscosity on the molecular characteristics of the polymers. However, the GP-generated nonlinear models are more compact and contain fewer parameters. All of the hybrid models shown here are simple to generate, accurate, and portable, meaning that they can be easily leveraged across a variety of modeling platforms Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900860y

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Optimal allocation procedure for gas-lift optimization / Kashif Rashid in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2286–2294 Titre : Optimal allocation procedure for gas-lift optimization Type de document : texte imprimé Auteurs : Kashif Rashid, Auteur Année de publication : 2010 Article en page(s) : pp. 2286–2294 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Gas-Lift Résumé : This paper presents an optimal allocation procedure (referred to as the Newton reduction method) which based on an upper convex profile requirement reduces a high dimensional problem into one of a single variable. This allocation procedure is used in a methodology designed for the treatment of the gas-lift optimization problem. This problem is encountered in the oil industry and specifically concerns the distribution of a fixed quantity of lift gas over a number of wells in order to increase the field production capability. The allocation procedure is applied by enforcing the notion of well separability and the availability of upper convex lift profiles for each well. However, due to the effects of interdependent wells, the procedure is performed iteratively until convergence on wellhead pressures. The approach reported is shown to be several times more efficient than traditional approaches in computational and time costs, while delivering comparable results. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900867r [article] Optimal allocation procedure for gas-lift optimization [texte imprimé] / Kashif Rashid, Auteur . - 2010 . - pp. 2286–2294. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2286–2294 Mots-clés : Gas-Lift Résumé : This paper presents an optimal allocation procedure (referred to as the Newton reduction method) which based on an upper convex profile requirement reduces a high dimensional problem into one of a single variable. This allocation procedure is used in a methodology designed for the treatment of the gas-lift optimization problem. This problem is encountered in the oil industry and specifically concerns the distribution of a fixed quantity of lift gas over a number of wells in order to increase the field production capability. The allocation procedure is applied by enforcing the notion of well separability and the availability of upper convex lift profiles for each well. However, due to the effects of interdependent wells, the procedure is performed iteratively until convergence on wellhead pressures. The approach reported is shown to be several times more efficient than traditional approaches in computational and time costs, while delivering comparable results. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900867r

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Energy requirement of a distillation/membrane parallel hybrid / Etienne Ayotte-Sauvé in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) Titre : Energy requirement of a distillation/membrane parallel hybrid : a thermodynamic approach Type de document : texte imprimé Auteurs : Etienne Ayotte-Sauvé, Auteur ; Mikhail Sorin, Auteur ; Fernand Rheault, Auteur Année de publication : 2010 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Energy Requirement  Power of separation  Distillation  Membrane Parallel Hybrid Résumé : This paper presents a new thermodynamic approach, based on the notion of power of separation, for the retrofit problem of finding the minimal energy requirement of an existing binary distillation column when coupling it in parallel with a membrane unit. A new geometric interpretation of this concept, which is supported by a rigorous mathematical proof, is introduced. From it results an efficient and accurate shortcut method to tackle the aforementioned problem. Numerical examples are considered for the energy intensive separation of olefins from paraffins, namely the retrofit of a C3-splitter and the retrofit of a C2-splitter through parallel hybridization with facilitated transport membranes. The results of the proposed shortcut method are compared to those obtained via the nonlinear programming optimization solvers GAMS-CONOPT and GAMS-CoinIpopt for a superstructure based problem formulation, which act as a reference. In both case studies, the shortcut method results in a significant reduction in problem size and in the number of solver iterations, while yielding only a small error on the minimal energy requirement of the column within the hybrid and on the hybrid architecture (i.e., the position of side-streams along the column). It could therefore be used to carry out a rapid screening of alternatives (e.g., different membrane technologies) in order to evaluate potential energy improvements. The proposed approach could also provide mathematical programming algorithms with a good initial guess of the solution. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9009155 [article] Energy requirement of a distillation/membrane parallel hybrid : a thermodynamic approach [texte imprimé] / Etienne Ayotte-Sauvé, Auteur ; Mikhail Sorin, Auteur ; Fernand Rheault, Auteur . - 2010. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) Mots-clés : Energy Requirement  Power of separation  Distillation  Membrane Parallel Hybrid Résumé : This paper presents a new thermodynamic approach, based on the notion of power of separation, for the retrofit problem of finding the minimal energy requirement of an existing binary distillation column when coupling it in parallel with a membrane unit. A new geometric interpretation of this concept, which is supported by a rigorous mathematical proof, is introduced. From it results an efficient and accurate shortcut method to tackle the aforementioned problem. Numerical examples are considered for the energy intensive separation of olefins from paraffins, namely the retrofit of a C3-splitter and the retrofit of a C2-splitter through parallel hybridization with facilitated transport membranes. The results of the proposed shortcut method are compared to those obtained via the nonlinear programming optimization solvers GAMS-CONOPT and GAMS-CoinIpopt for a superstructure based problem formulation, which act as a reference. In both case studies, the shortcut method results in a significant reduction in problem size and in the number of solver iterations, while yielding only a small error on the minimal energy requirement of the column within the hybrid and on the hybrid architecture (i.e., the position of side-streams along the column). It could therefore be used to carry out a rapid screening of alternatives (e.g., different membrane technologies) in order to evaluate potential energy improvements. The proposed approach could also provide mathematical programming algorithms with a good initial guess of the solution. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9009155

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Fuzzy optimization of continuous fermentations with cell recycling for ethanol production / Feng-Sheng Wang in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2306–2311 Titre : Fuzzy optimization of continuous fermentations with cell recycling for ethanol production Type de document : texte imprimé Auteurs : Feng-Sheng Wang, Auteur ; Hsun-Tung Lin, Auteur Année de publication : 2010 Article en page(s) : pp. 2306–2311 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Bioprocess  Fermentation  Ethanol Résumé : In this study, we considered a bioprocess optimization problem for continuous ethanol fermentation with cell recycling. The aim of the optimization problem was to obtain the maximum overall productivity and conversion subject to the interval inequality constraints for residual glucose concentration and the total amount of glucose supplied. The residual glucose not only leads to a loss of revenue but also can create environmental problems, such that employing both constraints has benefits for both operating costs and environmental impact. A fuzzy goal attainment method was introduced to the multiobjective problem in order to obtain a trade-off solution. From the computational results, the overall productivity of the continuous fermentation process with cell recycling allowed for a higher dilution rate, such that the overall productivity was about 7.3-fold higher than that of a continuous mixed-flow fermentation process. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901066a [article] Fuzzy optimization of continuous fermentations with cell recycling for ethanol production [texte imprimé] / Feng-Sheng Wang, Auteur ; Hsun-Tung Lin, Auteur . - 2010 . - pp. 2306–2311. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2306–2311 Mots-clés : Bioprocess  Fermentation  Ethanol Résumé : In this study, we considered a bioprocess optimization problem for continuous ethanol fermentation with cell recycling. The aim of the optimization problem was to obtain the maximum overall productivity and conversion subject to the interval inequality constraints for residual glucose concentration and the total amount of glucose supplied. The residual glucose not only leads to a loss of revenue but also can create environmental problems, such that employing both constraints has benefits for both operating costs and environmental impact. A fuzzy goal attainment method was introduced to the multiobjective problem in order to obtain a trade-off solution. From the computational results, the overall productivity of the continuous fermentation process with cell recycling allowed for a higher dilution rate, such that the overall productivity was about 7.3-fold higher than that of a continuous mixed-flow fermentation process. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901066a

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Generalized disjunctive programming for synthesis of rice drying processes / Abdunnaser Younes in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2312–2325 Titre : Generalized disjunctive programming for synthesis of rice drying processes Type de document : texte imprimé Auteurs : Abdunnaser Younes, Auteur ; Wongphaka Wongrat, Auteur ; Ali Elkamel, Auteur Année de publication : 2010 Article en page(s) : pp. 2312–2325 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Rice drying  Generalized disjunctive programming Résumé : Rice drying synthesis is an essential operation that has to be done carefully and cost-effectively. Fast drying can cause fissuring, which lowers the market value of the rice grains. Multipass drying systems are therefore used to bring the moisture content to desired levels gradually. To determine the best configuration of units and their corresponding operating conditions that maximize rice quality and minimize energy consumption, empirical models are used. However, empirical models have limited ranges of validity. Moreover, different mathematical models are possible for the same synthesis problem. This paper proposes a generalized disjunctive programming (GDP) framework for the synthesis problem of rice drying in order to increase the overall range of applicability of the empirical models and establish a consistent solution strategy. The proposed framework is investigated and tested on several case studies. Different drying strategies resulted from solving the synthesis problem with different empirical models, providing us with a broader vision of the mechanism of rice drying processes. The results indicate that the GDP framework can facilitate the modeling of the synthesis problem and increase the efficiency of optimization algorithms. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901190v [article] Generalized disjunctive programming for synthesis of rice drying processes [texte imprimé] / Abdunnaser Younes, Auteur ; Wongphaka Wongrat, Auteur ; Ali Elkamel, Auteur . - 2010 . - pp. 2312–2325. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2312–2325 Mots-clés : Rice drying  Generalized disjunctive programming Résumé : Rice drying synthesis is an essential operation that has to be done carefully and cost-effectively. Fast drying can cause fissuring, which lowers the market value of the rice grains. Multipass drying systems are therefore used to bring the moisture content to desired levels gradually. To determine the best configuration of units and their corresponding operating conditions that maximize rice quality and minimize energy consumption, empirical models are used. However, empirical models have limited ranges of validity. Moreover, different mathematical models are possible for the same synthesis problem. This paper proposes a generalized disjunctive programming (GDP) framework for the synthesis problem of rice drying in order to increase the overall range of applicability of the empirical models and establish a consistent solution strategy. The proposed framework is investigated and tested on several case studies. Different drying strategies resulted from solving the synthesis problem with different empirical models, providing us with a broader vision of the mechanism of rice drying processes. The results indicate that the GDP framework can facilitate the modeling of the synthesis problem and increase the efficiency of optimization algorithms. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901190v

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Dynamic simulation of sorption enhanced reaction processes for biodiesel production / Ankur Kapil in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2326–2335 Titre : Dynamic simulation of sorption enhanced reaction processes for biodiesel production Type de document : texte imprimé Auteurs : Ankur Kapil, Auteur ; Shrikant A. Bhat, Auteur ; Jhuma Sadhukhan, Auteur Année de publication : 2010 Article en page(s) : pp. 2326–2335 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Dynamic simulation  Biodiesel  Sorption enhanced reactors  Fatty acid methyl ester  Simulated moving bed reactors Résumé : The objective of this work was to establish fixed bed sorption enhanced reactors (SER) and simulated moving bed reactors (SMBR) for the production of high purity biodiesel (fatty acid methyl ester, FAME) using esterification reactions between fatty acids (FA) in used oils and methanol. This study has demonstrated that these processes have tremendous potential in terms of overcoming the low conversion and separation difficulties that are faced in conventional biodiesel production processes. Additionally, the SMBR process operating conditions can be optimized to produce FAME at a desired purity in a continuous mode. The novelty of this work lays in the development of generic and comprehensive dynamic simulation and systematic parametric analysis frameworks. These were used to deduce the following operating conditions for achieving more than 90% conversion of FA and 80% purity of FAME, from an SMBR process: switching time of 900 s, length of 0.25 m, and feed, raffinate, and eluent flow rate ratios of 0.41, 0.49, and 0.75, for a given velocity of 2.4 × 10−4 m/s in the reaction zone. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901225u [article] Dynamic simulation of sorption enhanced reaction processes for biodiesel production [texte imprimé] / Ankur Kapil, Auteur ; Shrikant A. Bhat, Auteur ; Jhuma Sadhukhan, Auteur . - 2010 . - pp. 2326–2335. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2326–2335 Mots-clés : Dynamic simulation  Biodiesel  Sorption enhanced reactors  Fatty acid methyl ester  Simulated moving bed reactors Résumé : The objective of this work was to establish fixed bed sorption enhanced reactors (SER) and simulated moving bed reactors (SMBR) for the production of high purity biodiesel (fatty acid methyl ester, FAME) using esterification reactions between fatty acids (FA) in used oils and methanol. This study has demonstrated that these processes have tremendous potential in terms of overcoming the low conversion and separation difficulties that are faced in conventional biodiesel production processes. Additionally, the SMBR process operating conditions can be optimized to produce FAME at a desired purity in a continuous mode. The novelty of this work lays in the development of generic and comprehensive dynamic simulation and systematic parametric analysis frameworks. These were used to deduce the following operating conditions for achieving more than 90% conversion of FA and 80% purity of FAME, from an SMBR process: switching time of 900 s, length of 0.25 m, and feed, raffinate, and eluent flow rate ratios of 0.41, 0.49, and 0.75, for a given velocity of 2.4 × 10−4 m/s in the reaction zone. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901225u

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Nearest-neighbor method for the automatic maintenance of multivariate statistical soft sensors in batch processing / Pierantonio Facco in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2336–2347 Titre : Nearest-neighbor method for the automatic maintenance of multivariate statistical soft sensors in batch processing Type de document : texte imprimé Auteurs : Pierantonio Facco, Auteur ; Fabrizio Bezzo, Auteur ; Massimiliano Barolo, Auteur Année de publication : 2010 Article en page(s) : pp. 2336–2347 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Multivariate Statistical  Soft sensors  Batch polymerization Résumé : Soft sensors based on multivariate statistical models are used very frequently for the monitoring of batch processes. From the moment of model calibration onward, the model is usually assumed to be time-invariant. Unfortunately, batch process conditions are subject to several events that make the correlation structure between batches change with respect to that of the original model. This can determine a decay of the soft sensor performance, unless periodic maintenance (i.e., updating) of the model is carried out. This article proposes a methodology for the automatic maintenance of PLS soft sensors in batch processing. Whereas the adaptation scheme usually follows chronological order in classical recursive updating, the proposed strategy defines the reference data set for model recalibration as the set of batches (nearest neighbors) that are most similar to the currently running batch. The nearest neighbors to a running batch are identified during the initial evolution of the batch following a concept of proximity in the latent space of principal components. In this way, for any new batch to be run, a model can be tailored on the running batch itself. The effectiveness of the proposed updating methodology is evaluated in two case studies related to the development of adaptive soft sensors for real-time product quality monitoring: a simulated fed-batch process for the production of penicillin and an industrial batch polymerization process for the production of a resin. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9013919 [article] Nearest-neighbor method for the automatic maintenance of multivariate statistical soft sensors in batch processing [texte imprimé] / Pierantonio Facco, Auteur ; Fabrizio Bezzo, Auteur ; Massimiliano Barolo, Auteur . - 2010 . - pp. 2336–2347. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2336–2347 Mots-clés : Multivariate Statistical  Soft sensors  Batch polymerization Résumé : Soft sensors based on multivariate statistical models are used very frequently for the monitoring of batch processes. From the moment of model calibration onward, the model is usually assumed to be time-invariant. Unfortunately, batch process conditions are subject to several events that make the correlation structure between batches change with respect to that of the original model. This can determine a decay of the soft sensor performance, unless periodic maintenance (i.e., updating) of the model is carried out. This article proposes a methodology for the automatic maintenance of PLS soft sensors in batch processing. Whereas the adaptation scheme usually follows chronological order in classical recursive updating, the proposed strategy defines the reference data set for model recalibration as the set of batches (nearest neighbors) that are most similar to the currently running batch. The nearest neighbors to a running batch are identified during the initial evolution of the batch following a concept of proximity in the latent space of principal components. In this way, for any new batch to be run, a model can be tailored on the running batch itself. The effectiveness of the proposed updating methodology is evaluated in two case studies related to the development of adaptive soft sensors for real-time product quality monitoring: a simulated fed-batch process for the production of penicillin and an industrial batch polymerization process for the production of a resin. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9013919

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Application of micro-X-ray fluorescence analysis for the characterization of industrial wastes / Maria D. Alba in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2348–2352 Titre : Application of micro-X-ray fluorescence analysis for the characterization of industrial wastes Type de document : texte imprimé Auteurs : Maria D. Alba, Auteur ; Patricia Aparicio, Auteur ; Jose M. Benítez, Auteur Année de publication : 2010 Article en page(s) : pp. 2348–2352 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : X-ray  Industrial wastes Résumé : The issue of how to improve product quality and product yield in a short period of time is becoming more critical in many industries. Thus, shorter delay times between laboratory analysis and process correction are important in process control. Elimination of sample handling and operator manipulation is desirable. The present article proposes micro-X-ray fluorescence (μXRF) as an economical control method for industrial product quality with a minimum time cost. Samples from different industrial processes have been chosen and analyzed by XRF and μXRF. The results show that the two techniques give similar results and that μXRF allows the waste to be classified and is able to detect problems in the production process. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901716w [article] Application of micro-X-ray fluorescence analysis for the characterization of industrial wastes [texte imprimé] / Maria D. Alba, Auteur ; Patricia Aparicio, Auteur ; Jose M. Benítez, Auteur . - 2010 . - pp. 2348–2352. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2348–2352 Mots-clés : X-ray  Industrial wastes Résumé : The issue of how to improve product quality and product yield in a short period of time is becoming more critical in many industries. Thus, shorter delay times between laboratory analysis and process correction are important in process control. Elimination of sample handling and operator manipulation is desirable. The present article proposes micro-X-ray fluorescence (μXRF) as an economical control method for industrial product quality with a minimum time cost. Samples from different industrial processes have been chosen and analyzed by XRF and μXRF. The results show that the two techniques give similar results and that μXRF allows the waste to be classified and is able to detect problems in the production process. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901716w

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Sorption of methane, nitrogen, oxygen, and argon in ZSM-5 with different SiO2/Al2O3 ratios / Govind Sethia in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2353–2362 Titre : Sorption of methane, nitrogen, oxygen, and argon in ZSM-5 with different SiO2/Al2O3 ratios : grand canonical monte carlo simulation and volumetric measurements Type de document : texte imprimé Auteurs : Govind Sethia, Auteur ; Renjith S. Pillai, Auteur ; Ganga P. Dangi, Auteur Année de publication : 2010 Article en page(s) : pp. 2353–2362 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Methane  Nitrogen  Oxygen  Volumetric measurements Résumé : Sorption of CH4, N2, O2, and Ar in ZSM-5 with different SiO2/Al2O3 ratios was studied by volumetric measurements and grand canonical Monte Carlo simulation. Sorption capacity for all the gases studied was observed to decrease with an increase in the SiO2/Al2O3 ratio of ZSM-5. The sorption selectivity of CH4 over N2 increases, whereas sorption selectivities of N2 over O2 and Ar decrease with an increase in the SiO2/Al2O3 ratio of ZSM-5. ZSM-5 with SiO2/Al2O3 of 900 showed higher selectivity for CH4 over N2, whereas the SiO2/Al2O3 ratio of 25 showed higher N2 selectivity over O2 and Ar. The heats of adsorption for CH4 and N2 decrease and that for O2 and Ar remain unaffected with an increase in SiO2/Al2O3 ratio of ZSM-5. The values of Henry’s constant were also calculated for CH4, N2, O2, and Ar for adsorption in ZSM-5 having varied SiO2/Al2O3 ratio. The experimental results were compared with theoretically calculated data using grand canonical Monte Carlo (GCMC) simulation. Simulation studies expectedly showed the proximity of N2 molecules to the sites occupied by extraframework sodium cations. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900280w [article] Sorption of methane, nitrogen, oxygen, and argon in ZSM-5 with different SiO2/Al2O3 ratios : grand canonical monte carlo simulation and volumetric measurements [texte imprimé] / Govind Sethia, Auteur ; Renjith S. Pillai, Auteur ; Ganga P. Dangi, Auteur . - 2010 . - pp. 2353–2362. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2353–2362 Mots-clés : Methane  Nitrogen  Oxygen  Volumetric measurements Résumé : Sorption of CH4, N2, O2, and Ar in ZSM-5 with different SiO2/Al2O3 ratios was studied by volumetric measurements and grand canonical Monte Carlo simulation. Sorption capacity for all the gases studied was observed to decrease with an increase in the SiO2/Al2O3 ratio of ZSM-5. The sorption selectivity of CH4 over N2 increases, whereas sorption selectivities of N2 over O2 and Ar decrease with an increase in the SiO2/Al2O3 ratio of ZSM-5. ZSM-5 with SiO2/Al2O3 of 900 showed higher selectivity for CH4 over N2, whereas the SiO2/Al2O3 ratio of 25 showed higher N2 selectivity over O2 and Ar. The heats of adsorption for CH4 and N2 decrease and that for O2 and Ar remain unaffected with an increase in SiO2/Al2O3 ratio of ZSM-5. The values of Henry’s constant were also calculated for CH4, N2, O2, and Ar for adsorption in ZSM-5 having varied SiO2/Al2O3 ratio. The experimental results were compared with theoretically calculated data using grand canonical Monte Carlo (GCMC) simulation. Simulation studies expectedly showed the proximity of N2 molecules to the sites occupied by extraframework sodium cations. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900280w

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Techno-economic analysis of postcombustion processes for the capture of carbon dioxide from power plant flue gas / Marc-Oliver Schach in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2363–2370 Titre : Techno-economic analysis of postcombustion processes for the capture of carbon dioxide from power plant flue gas Type de document : texte imprimé Auteurs : Marc-Oliver Schach, Auteur ; Rüdiger Schneider, Auteur ; Henning Schramm, Auteur Année de publication : 2010 Article en page(s) : pp. 2363–2370 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Postcombustion  Carbon Dioxide  Flue Gas  Global warming Résumé : Capture and sequestration of CO2 from power plant flue gas have become an important issue in the discussion about global warming. Different concepts of capture are being pursued. The advantage of postcombustion processes, such as processes based on absorption and stripping, is the possibility of retrofitting a state-of-the-art power plant with a capture plant under reasonable effort. Capturing CO2 by using an absorption/stripping process requires energy in the form of electricity and steam both supplied by the power plant. The capture process thereby reduces the overall efficiency of the power plant by up to 13%pts (percentage points). Apart from the development of new solvents, alternative and novel configurations of the process can lower the energy requirements. Three alternative configurations are economically and technically evaluated and compared to a baseline process represented by a standard absorption/stripping process using monoethanolamine (MEA) as a solvent. Savings in cost of CO2-avoided of 2−5% were attained. Regarding the total power required, savings of 4−7% were obtained. The results showed that not the process with the highest energy savings has the lowest cost of CO2-avoided, but that the influence of rising investment costs of more complex configurations cannot be ignored. For a comprehensive analysis of different configurations it is essential to perform both an economic evaluation and a technical study. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900514t [article] Techno-economic analysis of postcombustion processes for the capture of carbon dioxide from power plant flue gas [texte imprimé] / Marc-Oliver Schach, Auteur ; Rüdiger Schneider, Auteur ; Henning Schramm, Auteur . - 2010 . - pp. 2363–2370. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2363–2370 Mots-clés : Postcombustion  Carbon Dioxide  Flue Gas  Global warming Résumé : Capture and sequestration of CO2 from power plant flue gas have become an important issue in the discussion about global warming. Different concepts of capture are being pursued. The advantage of postcombustion processes, such as processes based on absorption and stripping, is the possibility of retrofitting a state-of-the-art power plant with a capture plant under reasonable effort. Capturing CO2 by using an absorption/stripping process requires energy in the form of electricity and steam both supplied by the power plant. The capture process thereby reduces the overall efficiency of the power plant by up to 13%pts (percentage points). Apart from the development of new solvents, alternative and novel configurations of the process can lower the energy requirements. Three alternative configurations are economically and technically evaluated and compared to a baseline process represented by a standard absorption/stripping process using monoethanolamine (MEA) as a solvent. Savings in cost of CO2-avoided of 2−5% were attained. Regarding the total power required, savings of 4−7% were obtained. The results showed that not the process with the highest energy savings has the lowest cost of CO2-avoided, but that the influence of rising investment costs of more complex configurations cannot be ignored. For a comprehensive analysis of different configurations it is essential to perform both an economic evaluation and a technical study. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900514t

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Comparison of temperature effects on the salting out of poly(ethylene glycol) versus poly(ethylene oxide)−poly(propylene oxide) random copolymer / Meghna Dilip in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2371–2379 Titre : Comparison of temperature effects on the salting out of poly(ethylene glycol) versus poly(ethylene oxide)−poly(propylene oxide) random copolymer Type de document : texte imprimé Auteurs : Meghna Dilip, Auteur ; Scott T. Griffin, Auteur ; Scott K. Spear, Auteur Année de publication : 2010 Article en page(s) : pp. 2371–2379 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Random Copolymer  Poly(ethylene glycol)  oxide)  Poly(propylene Aqueous biphasic systems Résumé : In common with many poly(ethylene glycol)s (PEGs), a poly(ethylene oxide)−poly(propylene oxide) random copolymer (EO−PO, with EO/PO = 1:1.3) of molecular weight 3320 g·mol−1, known as Sunbright-3320 (SB-3320), can be salted out of aqueous solution using kosmotropic salts such as (NH4)2SO4 to form aqueous biphasic systems (ABSs) comprising upper polymer-rich and lower salt-rich aqueous phases. The effects of temperature on these liquid/liquid ABSs and related solid/liquid resin-based systems, where one end of the polymer has been covalently attached to a solid support, have been studied. Distribution ratios of NH499TcO4 were determined radiometrically at various polymer and salt concentrations and temperatures. SB-3320-grafted poly(styrene) resins exhibit opposite effects of variable-temperature partitioning compared to the SB-3320-based ABS. However, the results are complicated because of the conformational changes that are possible for the SB-3320 polymer. Enthalpy and entropy changes were found to be temperature-dependent. The differences observed between the distribution of 99TcO4− in EO−PO-based systems versus PEG-based systems can be attributed to the lower cloud point temperatures and probable conformational changes for the EO−PO systems. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901268m [article] Comparison of temperature effects on the salting out of poly(ethylene glycol) versus poly(ethylene oxide)−poly(propylene oxide) random copolymer [texte imprimé] / Meghna Dilip, Auteur ; Scott T. Griffin, Auteur ; Scott K. Spear, Auteur . - 2010 . - pp. 2371–2379. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2371–2379 Mots-clés : Random Copolymer  Poly(ethylene glycol)  oxide)  Poly(propylene Aqueous biphasic systems Résumé : In common with many poly(ethylene glycol)s (PEGs), a poly(ethylene oxide)−poly(propylene oxide) random copolymer (EO−PO, with EO/PO = 1:1.3) of molecular weight 3320 g·mol−1, known as Sunbright-3320 (SB-3320), can be salted out of aqueous solution using kosmotropic salts such as (NH4)2SO4 to form aqueous biphasic systems (ABSs) comprising upper polymer-rich and lower salt-rich aqueous phases. The effects of temperature on these liquid/liquid ABSs and related solid/liquid resin-based systems, where one end of the polymer has been covalently attached to a solid support, have been studied. Distribution ratios of NH499TcO4 were determined radiometrically at various polymer and salt concentrations and temperatures. SB-3320-grafted poly(styrene) resins exhibit opposite effects of variable-temperature partitioning compared to the SB-3320-based ABS. However, the results are complicated because of the conformational changes that are possible for the SB-3320 polymer. Enthalpy and entropy changes were found to be temperature-dependent. The differences observed between the distribution of 99TcO4− in EO−PO-based systems versus PEG-based systems can be attributed to the lower cloud point temperatures and probable conformational changes for the EO−PO systems. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901268m

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Electroflotation combined with flotation deinking of flexographic newsprint / Akpojotor Shemi in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2380–2387 Titre : Electroflotation combined with flotation deinking of flexographic newsprint Type de document : texte imprimé Auteurs : Akpojotor Shemi, Auteur ; Jeffery S. Hsieh, Auteur Année de publication : 2010 Article en page(s) : pp. 2380–2387 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : flotation  Flexographic  Deinking  Electrolytic Résumé : A semicontinuous flotation cell, which incorporates an electrolytic cell, was used to collect inks from newsprint pulp slurry. In general, longer pulping time has an adverse impact on deinking of 100% flexographic old newspaper or newsprint (flexo-ONP) while temperature has a positive impact on deinking. However, the use of electric field improved deinking efficiency—measured by the percent reduction in effective residual ink concentration (ERIC)—by as much as 5% at longer pulping time (25 min compared to 5 min). Higher temperature (40 °C compared to 25 °C) combined with the use of electric field further improved deinking efficiency by 5%. Furthermore, the impact of electric field assisted flotation is discussed in the context of the following variables: alkali charge (sodium hydroxide), float consistency (percent solids in the pulp suspension), surfactant and soap concentration, and the amount of flexo newsprint in a mixture of newspaper (or furnish)−newsprint. Unlike 100% flexo-ONP, the mixture of 48% flexo-ONP, 30% offset-ONP and 22% old magazine (OMG) contains both flexographic and offset inks, which have different ink sizes and chemistries. On average, considering all the variables, the use of electric field improved deinking efficiency by 3%. The best deinking efficiency was achieved at 1% consistency, when sodium hydroxide and surfactant and soap were added, combined with electric field. The deinking efficiency was corroborated with thermogravimetric analysis (TGA). Deinking efficiency is also discussed in terms of a deinking selectivity parameter called the Z-weighted factor. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9012985 [article] Electroflotation combined with flotation deinking of flexographic newsprint [texte imprimé] / Akpojotor Shemi, Auteur ; Jeffery S. Hsieh, Auteur . - 2010 . - pp. 2380–2387. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2380–2387 Mots-clés : flotation  Flexographic  Deinking  Electrolytic Résumé : A semicontinuous flotation cell, which incorporates an electrolytic cell, was used to collect inks from newsprint pulp slurry. In general, longer pulping time has an adverse impact on deinking of 100% flexographic old newspaper or newsprint (flexo-ONP) while temperature has a positive impact on deinking. However, the use of electric field improved deinking efficiency—measured by the percent reduction in effective residual ink concentration (ERIC)—by as much as 5% at longer pulping time (25 min compared to 5 min). Higher temperature (40 °C compared to 25 °C) combined with the use of electric field further improved deinking efficiency by 5%. Furthermore, the impact of electric field assisted flotation is discussed in the context of the following variables: alkali charge (sodium hydroxide), float consistency (percent solids in the pulp suspension), surfactant and soap concentration, and the amount of flexo newsprint in a mixture of newspaper (or furnish)−newsprint. Unlike 100% flexo-ONP, the mixture of 48% flexo-ONP, 30% offset-ONP and 22% old magazine (OMG) contains both flexographic and offset inks, which have different ink sizes and chemistries. On average, considering all the variables, the use of electric field improved deinking efficiency by 3%. The best deinking efficiency was achieved at 1% consistency, when sodium hydroxide and surfactant and soap were added, combined with electric field. The deinking efficiency was corroborated with thermogravimetric analysis (TGA). Deinking efficiency is also discussed in terms of a deinking selectivity parameter called the Z-weighted factor. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9012985

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Cu(II), Zn(II), Ni(II), and Cd(II) complexes with HEDP removal from industrial effluents on different Ion exchangers / Dorota Kołodyńska in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2388–2400 Titre : Cu(II), Zn(II), Ni(II), and Cd(II) complexes with HEDP removal from industrial effluents on different Ion exchangers Type de document : texte imprimé Auteurs : Dorota Kołodyńska, Auteur Année de publication : 2010 Article en page(s) : pp. 2388–2400 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Cu(II)  Zn(II)  Ni(II)  Cd(II)  Industrial Effluents Résumé : The aim of this research is to investigate sorption characteristic of polyacrylate anion exchangers and chelating ion exchangers for the removal of Cu(II), Zn(II), Ni(II), and Cd(II) complexes with HEDP (1-hydroxyethylene-1,1-diphosphonic acid) from aqueous solutions. Optimum sorption conditions were determined as a function of phase contact time (1−180 min), pH (5−13), ion exchanger dosage (0.1−1.0 g), temperature (293−333 K), and chloride ions concentration (0.01−0.5 mol/L of NaCl). The Langmuir, Freundlich, Temkin, and Dubinin−Radushkevich (D−R) models were applied to describe the adsorption isotherm of Cu(II), Zn(II), Ni(II), and Cd(II) complexes with HEDP on Amberlite IRA 458 and Amberlite IRA 958 as well as Purolite S-920 and Purolite S-930. In the case of M(II)−HEDP complexes the adsorption capacities of Amberlite 458 were found to be 1.96 meq/g for Cu(II), 3.94 meq/g for Zn(II), 2.98 meq/g for Ni(II), and 4.25 meq/g for Cd(II). The metal ions were desorbed using 1 M HCl. The ion exchange capacity of ion exchangers applied decreased 8% in the recovery of Cu(II)−HEDP after 10 times of the sorption−desorption processess. Experimental data were also tested in terms of sorption kinetics using the pseudo-first-order and pseudo-second-order kinetic models. The results showed that the sorption processes of Cu(II), Zn(II), Ni(II), and Cd(II) complexes with HEDP on Amberlite IRA 458 and Amberlite IRA 958 as well as Purolite S-920 and Purolite S-930 followed well the pseudo-second-order kinetics. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014414 [article] Cu(II), Zn(II), Ni(II), and Cd(II) complexes with HEDP removal from industrial effluents on different Ion exchangers [texte imprimé] / Dorota Kołodyńska, Auteur . - 2010 . - pp. 2388–2400. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2388–2400 Mots-clés : Cu(II)  Zn(II)  Ni(II)  Cd(II)  Industrial Effluents Résumé : The aim of this research is to investigate sorption characteristic of polyacrylate anion exchangers and chelating ion exchangers for the removal of Cu(II), Zn(II), Ni(II), and Cd(II) complexes with HEDP (1-hydroxyethylene-1,1-diphosphonic acid) from aqueous solutions. Optimum sorption conditions were determined as a function of phase contact time (1−180 min), pH (5−13), ion exchanger dosage (0.1−1.0 g), temperature (293−333 K), and chloride ions concentration (0.01−0.5 mol/L of NaCl). The Langmuir, Freundlich, Temkin, and Dubinin−Radushkevich (D−R) models were applied to describe the adsorption isotherm of Cu(II), Zn(II), Ni(II), and Cd(II) complexes with HEDP on Amberlite IRA 458 and Amberlite IRA 958 as well as Purolite S-920 and Purolite S-930. In the case of M(II)−HEDP complexes the adsorption capacities of Amberlite 458 were found to be 1.96 meq/g for Cu(II), 3.94 meq/g for Zn(II), 2.98 meq/g for Ni(II), and 4.25 meq/g for Cd(II). The metal ions were desorbed using 1 M HCl. The ion exchange capacity of ion exchangers applied decreased 8% in the recovery of Cu(II)−HEDP after 10 times of the sorption−desorption processess. Experimental data were also tested in terms of sorption kinetics using the pseudo-first-order and pseudo-second-order kinetic models. The results showed that the sorption processes of Cu(II), Zn(II), Ni(II), and Cd(II) complexes with HEDP on Amberlite IRA 458 and Amberlite IRA 958 as well as Purolite S-920 and Purolite S-930 followed well the pseudo-second-order kinetics. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014414

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Crystallization in a pilot evaporator / Mathias Gourdon in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2401–2409 Titre : Crystallization in a pilot evaporator : aqueous solutions of Na2CO3 and Na2SO4 Type de document : texte imprimé Auteurs : Mathias Gourdon, Auteur ; Lennart Vamling, Auteur Année de publication : 2010 Article en page(s) : pp. 2401–2409 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Sodium Résumé : Sodium carbonate and sodium sulfate cause problems by forming scales in black liquor evaporators, reducing heat transfer and cleaning intervals. An experimental investigation of the crystallization behavior during evaporation of different aqueous solutions of sodium carbonate and sodium sulfate has been carried out. The analysis is based on changes in heat transfer coefficients and crystal masses. The results from this work show large variation in the distribution of the crystal mass, depending on the composition of the solution. Solutions with the crystalline form of either dicarbonate or sodium carbonate exhibit high propensity to form scales on the heat transfer surface. Solutions with the crystalline form of burkeite, however, do not show the same attraction to the heat transfer surface; they are more likely to crystallize in the circulating solution. Thus, the heat transfer is not as affected as for dicarbonate or sodium carbonate. Note de contenu : bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901390c [article] Crystallization in a pilot evaporator : aqueous solutions of Na2CO3 and Na2SO4 [texte imprimé] / Mathias Gourdon, Auteur ; Lennart Vamling, Auteur . - 2010 . - pp. 2401–2409. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2401–2409 Mots-clés : Sodium Résumé : Sodium carbonate and sodium sulfate cause problems by forming scales in black liquor evaporators, reducing heat transfer and cleaning intervals. An experimental investigation of the crystallization behavior during evaporation of different aqueous solutions of sodium carbonate and sodium sulfate has been carried out. The analysis is based on changes in heat transfer coefficients and crystal masses. The results from this work show large variation in the distribution of the crystal mass, depending on the composition of the solution. Solutions with the crystalline form of either dicarbonate or sodium carbonate exhibit high propensity to form scales on the heat transfer surface. Solutions with the crystalline form of burkeite, however, do not show the same attraction to the heat transfer surface; they are more likely to crystallize in the circulating solution. Thus, the heat transfer is not as affected as for dicarbonate or sodium carbonate. Note de contenu : bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901390c

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Fractionation of used frying oil by supercritical CO2 and cosolvents / Jesusa Rincon in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2410–2418 Titre : Fractionation of used frying oil by supercritical CO2 and cosolvents Type de document : texte imprimé Auteurs : Jesusa Rincon, Auteur ; Rafael Camarillo, Auteur ; Luis Rodriguez, Auteur Année de publication : 2010 Article en page(s) : pp. 2410–2418 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Frying oil  CO2 Résumé : Supercritical extraction with pure and modified CO2 has been used for the fractionation of waste frying oil at different temperature and pressure conditions (25−80 °C and 300−400 kg/cm2). The cosolvents used to modify the CO2 behavior were ethanol, methanol, acetone, and hexane. They were selected because of their capacity to form hydrogen bonds. Both extraction rate and oil yield were larger under high density conditions (high pressure and low temperature). Further, when cosolvents were used, higher values of both variables were attained at softer operating pressures. Regarding the effect of cosolvents on these variables, it was found to follow this order: ethanol > methanol > acetone > hexane. The relative separation efficiency (RSE) of triglycerides (TG) from polar compounds with molecular weight higher than triglycerides (HMWC) was not greatly dependent on the operating conditions (pressure, temperature, cosolvent type, and cosolvent concentration). However, better values of the separation efficiency of TG from polar compounds with molecular weight lower than triglycerides (LMWC) were attained under low density conditions and using hexane as cosolvent. On the basis of the results relative to extraction rate, oil yield, and separation efficiency, the best extraction conditions were selected to separate a purified TG fraction from used frying oil. They were P = 300 kg/cm2, T = 40 °C, cosolvent type = hexane, and cosolvent concentration = 0.1 g of hexane/g of solvent. However, when processing the oil at these conditions, the polar content of the lipid fraction recovered still was about twice the fresh frying oil polar content. For this reason, a two-stage supercritical fluid extraction was performed. The composition of the fraction recovered in the two-stage process was very close to that of the fresh oil, a fact that clearly shows that the supercritical extraction with CO2 + hexane is an efficient method for the purification of the TG fraction of waste frying oil. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901871w [article] Fractionation of used frying oil by supercritical CO2 and cosolvents [texte imprimé] / Jesusa Rincon, Auteur ; Rafael Camarillo, Auteur ; Luis Rodriguez, Auteur . - 2010 . - pp. 2410–2418. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2410–2418 Mots-clés : Frying oil  CO2 Résumé : Supercritical extraction with pure and modified CO2 has been used for the fractionation of waste frying oil at different temperature and pressure conditions (25−80 °C and 300−400 kg/cm2). The cosolvents used to modify the CO2 behavior were ethanol, methanol, acetone, and hexane. They were selected because of their capacity to form hydrogen bonds. Both extraction rate and oil yield were larger under high density conditions (high pressure and low temperature). Further, when cosolvents were used, higher values of both variables were attained at softer operating pressures. Regarding the effect of cosolvents on these variables, it was found to follow this order: ethanol > methanol > acetone > hexane. The relative separation efficiency (RSE) of triglycerides (TG) from polar compounds with molecular weight higher than triglycerides (HMWC) was not greatly dependent on the operating conditions (pressure, temperature, cosolvent type, and cosolvent concentration). However, better values of the separation efficiency of TG from polar compounds with molecular weight lower than triglycerides (LMWC) were attained under low density conditions and using hexane as cosolvent. On the basis of the results relative to extraction rate, oil yield, and separation efficiency, the best extraction conditions were selected to separate a purified TG fraction from used frying oil. They were P = 300 kg/cm2, T = 40 °C, cosolvent type = hexane, and cosolvent concentration = 0.1 g of hexane/g of solvent. However, when processing the oil at these conditions, the polar content of the lipid fraction recovered still was about twice the fresh frying oil polar content. For this reason, a two-stage supercritical fluid extraction was performed. The composition of the fraction recovered in the two-stage process was very close to that of the fresh oil, a fact that clearly shows that the supercritical extraction with CO2 + hexane is an efficient method for the purification of the TG fraction of waste frying oil. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901871w

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Energy life cycle assessment for the production of biodiesel from rendered lipids in the united states / Dora E. López in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2419–2432 Titre : Energy life cycle assessment for the production of biodiesel from rendered lipids in the united states Type de document : texte imprimé Auteurs : Dora E. López, Auteur ; Joseph C. Mullins, Auteur ; David A. Bruce, Auteur Année de publication : 2010 Article en page(s) : pp. 2419–2432 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Biodiesel Résumé : The energy life cycle assessment for the production of biodiesel from rendered lipids in the United States is presented in this study. Three different scenarios were found eligible for analysis: (I) conversion to biodiesel, (II) rendering and conversion, and (III) farming, rendering, and conversion. The amounts of energy required in farming, meat processing, and baseline conversion to biodiesel were reviewed from the literature. The thermal energy and electricity used in rendering were surveyed from the U.S. rendering industry. For animal fats, scenario III resulted in a net energy ratio (NER, ratio of energy outputs to energy inputs) much lower than 1. In contrast, the NERs for scenarios I and II were both found to be >1. For scenario I, the NER was found to be >3.6, larger than the value typically reported for soybean oil (SBO) biodiesel. As for the waste SBO grease, the NER was found to be >1 for both applicable scenarios (I and II). To a limited extent, sensitivity analysis was used to evaluate changes in assumptions with respect to the type of fuels employed in the generation of thermal energy as well as the method for biodiesel production Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900884x [article] Energy life cycle assessment for the production of biodiesel from rendered lipids in the united states [texte imprimé] / Dora E. López, Auteur ; Joseph C. Mullins, Auteur ; David A. Bruce, Auteur . - 2010 . - pp. 2419–2432. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2419–2432 Mots-clés : Biodiesel Résumé : The energy life cycle assessment for the production of biodiesel from rendered lipids in the United States is presented in this study. Three different scenarios were found eligible for analysis: (I) conversion to biodiesel, (II) rendering and conversion, and (III) farming, rendering, and conversion. The amounts of energy required in farming, meat processing, and baseline conversion to biodiesel were reviewed from the literature. The thermal energy and electricity used in rendering were surveyed from the U.S. rendering industry. For animal fats, scenario III resulted in a net energy ratio (NER, ratio of energy outputs to energy inputs) much lower than 1. In contrast, the NERs for scenarios I and II were both found to be >1. For scenario I, the NER was found to be >3.6, larger than the value typically reported for soybean oil (SBO) biodiesel. As for the waste SBO grease, the NER was found to be >1 for both applicable scenarios (I and II). To a limited extent, sensitivity analysis was used to evaluate changes in assumptions with respect to the type of fuels employed in the generation of thermal energy as well as the method for biodiesel production Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900884x

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Prediction of solubilities of solid biomolecules in modified supercritical fluids using group contribution methods and equations of state / Thippawan Kumhom in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2433–2441 Titre : Prediction of solubilities of solid biomolecules in modified supercritical fluids using group contribution methods and equations of state Type de document : texte imprimé Auteurs : Thippawan Kumhom, Auteur ; Peter L. Douglas, Auteur ; Douglas Supaporn, Auteur Année de publication : 2010 Article en page(s) : pp. 2433–2441 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Biomolecules  Solubilities Résumé : A method to predict the solubilities of biomolecules in supercritical fluids (SCF) with cosolvents was developed, and predictions were compared with experimental data available in the literature. The method used the Constantinou−Gani and Joback group contribution methods to estimate pure component solute properties and the Lee−Kesler−Plöcker (LKP) and Mohsen-Nia−Moddaress−Mansoori (MMM) equations of state (EOS) to determine solute solubilities in the ternary solute−SCF−cosolvent systems. The ternary systems were modeled as pseudobinary systems with the SCF−cosolvent binary pair being modeled as a single pseudocomponent using Kay’s mixing rule to estimate the pseudocomponent properties. Twenty-one (21) systems consisting of polar and nonpolar solutes and cosolvents were evaluated over a range of temperatures, pressures, and cosolvent concentrations. The results demonstrated that both the LKP and MMM EOS are useful for modeling the solubility of solids in supercritical fluids (SCF) with cosolvents. When the Aromaticity index (AI) was less than or equal to 0.3, the MMM EOS was found to be more suitable; otherwise the LKP EOS was found to provide the best fit. If this so-called AI criterion was used, the average error between predicted and experimental results ranged from 0.5 to 25.5% with an average of 10.0% for the 21 systems studied. However, when the AI criterion was not followed, the error between predicted and experimental results ranged from 9.6 to 99% with an average of 69.0 Note de contenu : Blibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900945q [article] Prediction of solubilities of solid biomolecules in modified supercritical fluids using group contribution methods and equations of state [texte imprimé] / Thippawan Kumhom, Auteur ; Peter L. Douglas, Auteur ; Douglas Supaporn, Auteur . - 2010 . - pp. 2433–2441. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2433–2441 Mots-clés : Biomolecules  Solubilities Résumé : A method to predict the solubilities of biomolecules in supercritical fluids (SCF) with cosolvents was developed, and predictions were compared with experimental data available in the literature. The method used the Constantinou−Gani and Joback group contribution methods to estimate pure component solute properties and the Lee−Kesler−Plöcker (LKP) and Mohsen-Nia−Moddaress−Mansoori (MMM) equations of state (EOS) to determine solute solubilities in the ternary solute−SCF−cosolvent systems. The ternary systems were modeled as pseudobinary systems with the SCF−cosolvent binary pair being modeled as a single pseudocomponent using Kay’s mixing rule to estimate the pseudocomponent properties. Twenty-one (21) systems consisting of polar and nonpolar solutes and cosolvents were evaluated over a range of temperatures, pressures, and cosolvent concentrations. The results demonstrated that both the LKP and MMM EOS are useful for modeling the solubility of solids in supercritical fluids (SCF) with cosolvents. When the Aromaticity index (AI) was less than or equal to 0.3, the MMM EOS was found to be more suitable; otherwise the LKP EOS was found to provide the best fit. If this so-called AI criterion was used, the average error between predicted and experimental results ranged from 0.5 to 25.5% with an average of 10.0% for the 21 systems studied. However, when the AI criterion was not followed, the error between predicted and experimental results ranged from 9.6 to 99% with an average of 69.0 Note de contenu : Blibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900945q

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Structural properties of the poly(acrylonitrile) membrane prepared with different cast thicknesses / S. Azari in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2442–2448 Titre : Structural properties of the poly(acrylonitrile) membrane prepared with different cast thicknesses Type de document : texte imprimé Auteurs : S. Azari, Auteur ; M. Karimi, Auteur ; M. H. Kish, Auteur Année de publication : 2010 Article en page(s) : pp. 2442–2448 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Poly(acrylonitrile) Résumé : Decreasing the thickness of cast polymer solution in a membrane-forming system may lead to structure transition from finger- to spongelike structure. The shrinkage measurement of the cast poly(acrylonitrile) solutions reveals that the maximum value of shrinkage takes place when the macrovoids disappear from the structure. The solute rejection properties of membranes also show a different behavior between below and above the structure transition thickness. This experimental finding is explicable on the grounds of porosity variation of the membrane skin. The scanning electron micrograph of a cross-section membrane shows a nodular structure near the precipitation−bath interface, the structure of which is a result of spinodal demixing that is influenced by varying the thickness of the cast polymer solution. With the cast solution being regarded as two layers including a very thin top layer and a sublayer, closely packed spheres of polymer are considered for discussion of the thickness dependence of the structure evolution of the membranes. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900952v [article] Structural properties of the poly(acrylonitrile) membrane prepared with different cast thicknesses [texte imprimé] / S. Azari, Auteur ; M. Karimi, Auteur ; M. H. Kish, Auteur . - 2010 . - pp. 2442–2448. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2442–2448 Mots-clés : Poly(acrylonitrile) Résumé : Decreasing the thickness of cast polymer solution in a membrane-forming system may lead to structure transition from finger- to spongelike structure. The shrinkage measurement of the cast poly(acrylonitrile) solutions reveals that the maximum value of shrinkage takes place when the macrovoids disappear from the structure. The solute rejection properties of membranes also show a different behavior between below and above the structure transition thickness. This experimental finding is explicable on the grounds of porosity variation of the membrane skin. The scanning electron micrograph of a cross-section membrane shows a nodular structure near the precipitation−bath interface, the structure of which is a result of spinodal demixing that is influenced by varying the thickness of the cast polymer solution. With the cast solution being regarded as two layers including a very thin top layer and a sublayer, closely packed spheres of polymer are considered for discussion of the thickness dependence of the structure evolution of the membranes. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900952v

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Prediction of the basicity of aqueous amine solutions and the species distribution in the amine−H2O−CO2 system using the COSMO-RS method / Hidetaka Yamada in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2449–2455 Titre : Prediction of the basicity of aqueous amine solutions and the species distribution in the amine−H2O−CO2 system using the COSMO-RS method Type de document : texte imprimé Auteurs : Hidetaka Yamada, Auteur ; Shinkichi Shimizu, Auteur ; Hiromichi Okabe, Auteur Année de publication : 2010 Article en page(s) : pp. 2449–2455 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Amine−  H2O−  CO2  COSMO-RS Method Résumé : A conductor-like screening model for real solvents (COSMO-RS) was applied to the study of the amine−H2O−CO2 system. pKa values for 25 amines including a variety of alkanolamines and some cyclic or aromatic amines were calculated by the COSMO-RS method coupled with the density functional theory (DFT). The predictions of pKa values were compared using different DFT levels for geometry optimization and also with those based on another solvation model (SM5.4/A). The DFT-COSMO calculation at the BP/TZVP level has shown a relatively good correlation with experimental values for the 25 amines (R2 0.8) at a low computational cost. With this method, we have developed a calculation model to predict the equilibrium ratio between carbamate and bicarbonate anions in a CO2-loaded aqueous amine solution and have confirmed the validity of the prediction model by 13C NMR spectroscopy. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901185v [article] Prediction of the basicity of aqueous amine solutions and the species distribution in the amine−H2O−CO2 system using the COSMO-RS method [texte imprimé] / Hidetaka Yamada, Auteur ; Shinkichi Shimizu, Auteur ; Hiromichi Okabe, Auteur . - 2010 . - pp. 2449–2455. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2449–2455 Mots-clés : Amine−  H2O−  CO2  COSMO-RS Method Résumé : A conductor-like screening model for real solvents (COSMO-RS) was applied to the study of the amine−H2O−CO2 system. pKa values for 25 amines including a variety of alkanolamines and some cyclic or aromatic amines were calculated by the COSMO-RS method coupled with the density functional theory (DFT). The predictions of pKa values were compared using different DFT levels for geometry optimization and also with those based on another solvation model (SM5.4/A). The DFT-COSMO calculation at the BP/TZVP level has shown a relatively good correlation with experimental values for the 25 amines (R2 0.8) at a low computational cost. With this method, we have developed a calculation model to predict the equilibrium ratio between carbamate and bicarbonate anions in a CO2-loaded aqueous amine solution and have confirmed the validity of the prediction model by 13C NMR spectroscopy. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901185v

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Modeling of particle size distribution for semibatch precipitation of barium sulfate using different activity coefficient models / C. Steyer in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2456–2468 Titre : Modeling of particle size distribution for semibatch precipitation of barium sulfate using different activity coefficient models Type de document : texte imprimé Auteurs : C. Steyer, Auteur ; M. Mangold, Auteur ; K. Sundmacher, Auteur Année de publication : 2010 Article en page(s) : pp. 2456–2468 Note générale : Indestrial Chemistry Langues : Anglais (eng) Mots-clés : Barium sulfate Résumé : Our recent experiments with precipitation of barium sulfate (Steyer et al. In BIWIC 15th International Workshop on Industrial Crystallization; Shaker VerlagAachen, Germany, 2008; pp 73−80. Steyer and Sundmacher J. Cryst. Growth 2009, 311, 2702−2708) showed that an excess of barium or sulfate ions in the crystallizer has a strong impact on the resulting particle size distributions (PSDs). Theoretically, this effect is not well understood, as most kinetic models in the literature are valid only for stoichiometric conditions. The aim of this work was, therefore, to investigate the influence of detailed thermodynamically well formulated activity coefficient models on the PSDs in a one-dimensional population balance model of a semibatch continuous stirred-tank reactor (CSTR). The nonsymmetry of these models with respect to an excess of barium or sulfate ions was studied. It was found that the effect on the supersaturation is too weak to explain the experimental results in terms of supersaturation-dependent kinetics. It was thus concluded that, for the conditions studied here, it is not sufficient to use nucleation kinetics that depend on supersaturation only. Instead, the actual ratio of ions in the solution should be incorporated into the kinetic expression for nucleation Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901306r [article] Modeling of particle size distribution for semibatch precipitation of barium sulfate using different activity coefficient models [texte imprimé] / C. Steyer, Auteur ; M. Mangold, Auteur ; K. Sundmacher, Auteur . - 2010 . - pp. 2456–2468. Indestrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2456–2468 Mots-clés : Barium sulfate Résumé : Our recent experiments with precipitation of barium sulfate (Steyer et al. In BIWIC 15th International Workshop on Industrial Crystallization; Shaker VerlagAachen, Germany, 2008; pp 73−80. Steyer and Sundmacher J. Cryst. Growth 2009, 311, 2702−2708) showed that an excess of barium or sulfate ions in the crystallizer has a strong impact on the resulting particle size distributions (PSDs). Theoretically, this effect is not well understood, as most kinetic models in the literature are valid only for stoichiometric conditions. The aim of this work was, therefore, to investigate the influence of detailed thermodynamically well formulated activity coefficient models on the PSDs in a one-dimensional population balance model of a semibatch continuous stirred-tank reactor (CSTR). The nonsymmetry of these models with respect to an excess of barium or sulfate ions was studied. It was found that the effect on the supersaturation is too weak to explain the experimental results in terms of supersaturation-dependent kinetics. It was thus concluded that, for the conditions studied here, it is not sufficient to use nucleation kinetics that depend on supersaturation only. Instead, the actual ratio of ions in the solution should be incorporated into the kinetic expression for nucleation Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901306r

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Analysis of shrinkage development of a semicrystalline polymer during injection molding / Santis De Felice in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2469–2476 Titre : Analysis of shrinkage development of a semicrystalline polymer during injection molding Type de document : texte imprimé Auteurs : Santis De Felice, Auteur ; Roberto Pantani, Auteur ; Vito Speranza, Auteur Année de publication : 2010 Article en page(s) : pp. 2469–2476 Note générale : Idustrial Chemistry Langues : Anglais (eng) Mots-clés : Polymers  Semicrystalline Résumé : The phenomenon of shrinkage in injection molding is particularly relevant for the processing of semicrystalline polymers. Nevertheless, if compared with the considerable effort spent by researchers to investigate the evolution of shrinkage and thermal stresses in amorphous polymers, the research work devoted to shrinkage of semicrystalline polymers is rather limited in the literature. In this work, the influence of holding pressure and time, and geometric constraints, on the shrinkage of a semicrystalline polymer was explored. Adopting a technique based on strain gauges, the time at which shrinkage started inside the mold was measured as a function of the holding pressure. Experimental results were compared with predictions for shrinkage obtained by a code developed at the University of Salerno, which takes into account crystallization kinetics and the effect of crystallinity on material properties. In particular, a solidification criterion based on the degree of crystallinity was identified Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901316p [article] Analysis of shrinkage development of a semicrystalline polymer during injection molding [texte imprimé] / Santis De Felice, Auteur ; Roberto Pantani, Auteur ; Vito Speranza, Auteur . - 2010 . - pp. 2469–2476. Idustrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2469–2476 Mots-clés : Polymers  Semicrystalline Résumé : The phenomenon of shrinkage in injection molding is particularly relevant for the processing of semicrystalline polymers. Nevertheless, if compared with the considerable effort spent by researchers to investigate the evolution of shrinkage and thermal stresses in amorphous polymers, the research work devoted to shrinkage of semicrystalline polymers is rather limited in the literature. In this work, the influence of holding pressure and time, and geometric constraints, on the shrinkage of a semicrystalline polymer was explored. Adopting a technique based on strain gauges, the time at which shrinkage started inside the mold was measured as a function of the holding pressure. Experimental results were compared with predictions for shrinkage obtained by a code developed at the University of Salerno, which takes into account crystallization kinetics and the effect of crystallinity on material properties. In particular, a solidification criterion based on the degree of crystallinity was identified Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901316p

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Factors affecting wood dissolution and regeneration of Ionic lquids / Bin Li in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2477–2484 Titre : Factors affecting wood dissolution and regeneration of Ionic lquids Type de document : texte imprimé Auteurs : Bin Li, Auteur ; Janne Asikkala, Auteur ; Ilari Filpponen, Auteur Année de publication : 2010 Article en page(s) : pp. 2477–2484 Note générale : Idustrial Chemistry Langues : Anglais (eng) Mots-clés : Wood  Cellulase enzymatic  Ionic liquids Résumé : Three wood species, eucalyptus grandis (E. grandis), southern pine (S. pine), and Norway spruce thermomechanical pulp (N. spruce TMP) were pretreated by dissolution in the ionic liquid (IL) 1-allyl-3-methylimidazolium chloride ([AMIM]Cl). The wood was regenerated from the ionic liquid in high yield and the recycling of the ionic liquid was nearly quantitative. The lignin contents and the efficiencies of cellulase enzymatic hydrolyses of the regenerated wood were examined offering an understanding into the IL pretreatment efficiency. The components that remained within the recycled ILs were qualitatively characterized by 31P NMR spectroscopy. Wood density, pulverization intensity, and the nature of the regeneration nonsolvents were investigated as factors affecting the overall process. An increase in the wood density decreased the efficiency of the pretreatment, whereas extended pulverization periods decreased the yield of the regenerated wood after the IL pretreatment,with more glucose being released during the enzymatic hydrolysis. The yield of wood after IL pretreatment using water as the regeneration nonsolvent was found to be much higher than that of using methanol. As the reuse cycles of IL increased the wood regeneration yield increased, while certain wood components enriched within the recycled IL. The efficiency of cellulase enzymatic hydrolysis on the regenerated wood decreased with increasing reuse cycles of the IL. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901560p [article] Factors affecting wood dissolution and regeneration of Ionic lquids [texte imprimé] / Bin Li, Auteur ; Janne Asikkala, Auteur ; Ilari Filpponen, Auteur . - 2010 . - pp. 2477–2484. Idustrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2477–2484 Mots-clés : Wood  Cellulase enzymatic  Ionic liquids Résumé : Three wood species, eucalyptus grandis (E. grandis), southern pine (S. pine), and Norway spruce thermomechanical pulp (N. spruce TMP) were pretreated by dissolution in the ionic liquid (IL) 1-allyl-3-methylimidazolium chloride ([AMIM]Cl). The wood was regenerated from the ionic liquid in high yield and the recycling of the ionic liquid was nearly quantitative. The lignin contents and the efficiencies of cellulase enzymatic hydrolyses of the regenerated wood were examined offering an understanding into the IL pretreatment efficiency. The components that remained within the recycled ILs were qualitatively characterized by 31P NMR spectroscopy. Wood density, pulverization intensity, and the nature of the regeneration nonsolvents were investigated as factors affecting the overall process. An increase in the wood density decreased the efficiency of the pretreatment, whereas extended pulverization periods decreased the yield of the regenerated wood after the IL pretreatment,with more glucose being released during the enzymatic hydrolysis. The yield of wood after IL pretreatment using water as the regeneration nonsolvent was found to be much higher than that of using methanol. As the reuse cycles of IL increased the wood regeneration yield increased, while certain wood components enriched within the recycled IL. The efficiency of cellulase enzymatic hydrolysis on the regenerated wood decreased with increasing reuse cycles of the IL. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901560p

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Characteristics of the pulsatile flow in a self-excited pulse combustor tailpipe / Zhai Ming in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2485–2492 Titre : Characteristics of the pulsatile flow in a self-excited pulse combustor tailpipe Type de document : texte imprimé Auteurs : Zhai Ming, Auteur ; Dong Peng, Auteur Année de publication : 2010 Article en page(s) : pp. 2485–2492 Note générale : Idusrtial Chimestry Langues : Anglais (eng) Mots-clés : Combustor Résumé : This paper designs and describes a self-excited pulse combustion system. The experimental result shows that combustion oscillations can be produced with a steady supply of fuel and air without mechanical or aerodynamic valves. A large decoupling chamber with an exhaust pipe is connected at the end of the tailpipe of the pulse combustor. The temperatures and pressures along the tailpipe are measured. Pulsatile flow in the self-excited pulse combustor tailpipe is numerically simulated by FLUENT. A study case based on the experimental measurement data is simulated with compressible flow equations. Numerical simulation results which are close to the experimental measurement data show that the main characteristics are the increase in velocity amplitude and the decrease in mean velocity along the tailpipe, and the profiles of velocity at the tailpipe exit behave more like laminar pulsatile flows, whereas the profiles of velocity far away from the tailpipe exit behave like turbulence pulsatile flows. The profile of mean temperature along the tailpipe is affected only within a short distance from the tailpipe exit, where the amplitude of mass flow rate oscillation significantly increases. The pressure amplitude gradient is greater near the tailpipe exit than upstream. The pulsatile flow in the tailpipe of the self-excited pulse combustor behaves like an acoustic resonance in a Schmidt pulse combustor. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901979a [article] Characteristics of the pulsatile flow in a self-excited pulse combustor tailpipe [texte imprimé] / Zhai Ming, Auteur ; Dong Peng, Auteur . - 2010 . - pp. 2485–2492. Idusrtial Chimestry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2485–2492 Mots-clés : Combustor Résumé : This paper designs and describes a self-excited pulse combustion system. The experimental result shows that combustion oscillations can be produced with a steady supply of fuel and air without mechanical or aerodynamic valves. A large decoupling chamber with an exhaust pipe is connected at the end of the tailpipe of the pulse combustor. The temperatures and pressures along the tailpipe are measured. Pulsatile flow in the self-excited pulse combustor tailpipe is numerically simulated by FLUENT. A study case based on the experimental measurement data is simulated with compressible flow equations. Numerical simulation results which are close to the experimental measurement data show that the main characteristics are the increase in velocity amplitude and the decrease in mean velocity along the tailpipe, and the profiles of velocity at the tailpipe exit behave more like laminar pulsatile flows, whereas the profiles of velocity far away from the tailpipe exit behave like turbulence pulsatile flows. The profile of mean temperature along the tailpipe is affected only within a short distance from the tailpipe exit, where the amplitude of mass flow rate oscillation significantly increases. The pressure amplitude gradient is greater near the tailpipe exit than upstream. The pulsatile flow in the tailpipe of the self-excited pulse combustor behaves like an acoustic resonance in a Schmidt pulse combustor. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901979a

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Analysis and classification of the paper surface / Marco S. Reis in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2493–2502 Titre : Analysis and classification of the paper surface Type de document : texte imprimé Auteurs : Marco S. Reis, Auteur ; Pedro M. Saraiva, Auteur Année de publication : 2010 Article en page(s) : pp. 2493–2502 Note générale : Idustrial Chemistry Langues : Anglais (eng) Mots-clés : Paper Surface Résumé : Growing demands on paper quality impel papermakers to found new, robust, and reliable methodologies to evaluate paper properties, directly aligned with consumer preferences. In this paper, we address the development of such methodologies, focused on two different aspects of the paper surface: surface roughness and surface waviness. Using profilometry measurements and quality assessments made by a panel of experts, we have developed and tested several classification methodologies in order to emulate their evaluations, by combining different feature extraction techniques with classifiers representing a variety of statistical methods commonly applied. The current standard method to infer roughness, the Bendtsen tester, was also analyzed, in order to cast some light on how its measurements are affected by fundamental parameters of the paper surface. Results obtained show that it is indeed possible to develop a suitable classifier for inferring the quality of paper roughness in three classes (good/medium/bad) and for paper waviness in two classes (good/not good). Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901688w [article] Analysis and classification of the paper surface [texte imprimé] / Marco S. Reis, Auteur ; Pedro M. Saraiva, Auteur . - 2010 . - pp. 2493–2502. Idustrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2493–2502 Mots-clés : Paper Surface Résumé : Growing demands on paper quality impel papermakers to found new, robust, and reliable methodologies to evaluate paper properties, directly aligned with consumer preferences. In this paper, we address the development of such methodologies, focused on two different aspects of the paper surface: surface roughness and surface waviness. Using profilometry measurements and quality assessments made by a panel of experts, we have developed and tested several classification methodologies in order to emulate their evaluations, by combining different feature extraction techniques with classifiers representing a variety of statistical methods commonly applied. The current standard method to infer roughness, the Bendtsen tester, was also analyzed, in order to cast some light on how its measurements are affected by fundamental parameters of the paper surface. Results obtained show that it is indeed possible to develop a suitable classifier for inferring the quality of paper roughness in three classes (good/medium/bad) and for paper waviness in two classes (good/not good). Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901688w

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Quality pulp from mixed softwoods as an added value coproduct of a biorefinery / Jean-Michel Lavoie in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2503–2509 Titre : Quality pulp from mixed softwoods as an added value coproduct of a biorefinery Type de document : texte imprimé Auteurs : Jean-Michel Lavoie, Auteur ; Eva Capek-Menard, Auteur ; Henri Gauvin, Auteur ; Esteban Chornet, Auteur Année de publication : 2010 Article en page(s) : pp. 2503–2509 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Softwoods Résumé : Increasing prices for biomass and growing competition generated by the emerging biofuels sector will require drastic changes in current methods used for the transformation of lignocellulosic biomass to achieve profitability. In this work, a methodology known as “feedstock impregnation rapid and sequential steam treatment” (FIRSST) was used for the production of pulp from mixed softwoods. This method allows the isolation of the extractives, hemicelluloses, lignin, and most significantly, the cellulose fiber from the feedstock. The isolation of the cellulosic pulp was done via two successive steam treatments in which only the second required the addition of a catalyst (10 wt % NaOH) for delignification. The macromolecular contents of the residual solids along the different steps of the transformation were evaluated using ASTM and TAPPI standard methods. Carbohydrates were identified and quantified using high-performance liquid chromatography with an anion-exchange stationary phase. The quality of the FIRSST and Kraft pulp produced from the same feedstock was evaluated using standard ATPPC methods Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901763h [article] Quality pulp from mixed softwoods as an added value coproduct of a biorefinery [texte imprimé] / Jean-Michel Lavoie, Auteur ; Eva Capek-Menard, Auteur ; Henri Gauvin, Auteur ; Esteban Chornet, Auteur . - 2010 . - pp. 2503–2509. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2503–2509 Mots-clés : Softwoods Résumé : Increasing prices for biomass and growing competition generated by the emerging biofuels sector will require drastic changes in current methods used for the transformation of lignocellulosic biomass to achieve profitability. In this work, a methodology known as “feedstock impregnation rapid and sequential steam treatment” (FIRSST) was used for the production of pulp from mixed softwoods. This method allows the isolation of the extractives, hemicelluloses, lignin, and most significantly, the cellulose fiber from the feedstock. The isolation of the cellulosic pulp was done via two successive steam treatments in which only the second required the addition of a catalyst (10 wt % NaOH) for delignification. The macromolecular contents of the residual solids along the different steps of the transformation were evaluated using ASTM and TAPPI standard methods. Carbohydrates were identified and quantified using high-performance liquid chromatography with an anion-exchange stationary phase. The quality of the FIRSST and Kraft pulp produced from the same feedstock was evaluated using standard ATPPC methods Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901763h

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Numerical study of Isothermal flow and mixing characteristics in a cyclone-jet hybrid combustor / Cheol-Hong Hwang in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2510–2520 Titre : Numerical study of Isothermal flow and mixing characteristics in a cyclone-jet hybrid combustor Type de document : texte imprimé Auteurs : Cheol-Hong Hwang, Auteur ; Gwon Hyun Ko, Auteur Année de publication : 2010 Article en page(s) : pp. 2510–2520 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Hybrid combustor Résumé : The isothermal flow and mixing characteristics of a cyclone-jet hybrid combustor using a combination of cyclone premixed and jet diffusion flames were numerically investigated. The computational fluid dynamics model was validated with experimental results for a cyclone-jet premixed combustor. Good agreement was obtained between the simulated and experimental results. As a result, in the diffusion combustion (DC) mode, the cyclone flow velocity played an important role on the development of swirling flow patterns, but the improvement of fuel−air mixing was limited due to low interaction between axial jet and cyclone flows. On the other hand, the fuel−air mixing characteristics in the hybrid combustion (HC) mode were significantly better than those for the DC mode. Through the modification of axial nozzle geometry, it was found that both the distributed fuel (DF) and multihole fuel (MF) nozzles provided improved fuel−air mixing compared to the single-fuel (SF) nozzle. Finally, it was confirmed with previous experimental results that the detailed understanding of complex flow structure and mixing phenomenon conducted in the present study was very useful for the advanced combustor design in terms of flame stability and pollutant emissions Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901797c [article] Numerical study of Isothermal flow and mixing characteristics in a cyclone-jet hybrid combustor [texte imprimé] / Cheol-Hong Hwang, Auteur ; Gwon Hyun Ko, Auteur . - 2010 . - pp. 2510–2520. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2510–2520 Mots-clés : Hybrid combustor Résumé : The isothermal flow and mixing characteristics of a cyclone-jet hybrid combustor using a combination of cyclone premixed and jet diffusion flames were numerically investigated. The computational fluid dynamics model was validated with experimental results for a cyclone-jet premixed combustor. Good agreement was obtained between the simulated and experimental results. As a result, in the diffusion combustion (DC) mode, the cyclone flow velocity played an important role on the development of swirling flow patterns, but the improvement of fuel−air mixing was limited due to low interaction between axial jet and cyclone flows. On the other hand, the fuel−air mixing characteristics in the hybrid combustion (HC) mode were significantly better than those for the DC mode. Through the modification of axial nozzle geometry, it was found that both the distributed fuel (DF) and multihole fuel (MF) nozzles provided improved fuel−air mixing compared to the single-fuel (SF) nozzle. Finally, it was confirmed with previous experimental results that the detailed understanding of complex flow structure and mixing phenomenon conducted in the present study was very useful for the advanced combustor design in terms of flame stability and pollutant emissions Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901797c

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Evidence of competitive adsorption of Sb(III) and As(III) on activated alumina / Florence Bullough in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2521–2524 Titre : Evidence of competitive adsorption of Sb(III) and As(III) on activated alumina Type de document : texte imprimé Auteurs : Florence Bullough, Auteur ; Dominik J Weiss, Auteur ; William E Dubbin, Auteur Année de publication : 2010 Article en page(s) : pp. 2521–2524 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Sb(III)  As(III)  Alumina Résumé : The impact of Sb(III) on the removal of As(III) from solution with activated alumina (AA), a widely employed low cost sorbent for various types of water treatments, was assessed. Adsorption isotherms were determined for binary element systems with As/Sb concentration ratios of 5:1, 9:1, and 12:1 to mimic conditions in water treatment facilities. These were compared to those established for single element systems. There was an increase in Sb(III) adsorption in the binary system compared to the Sb(III) only system. Conversely, in binary systems, As(III) adsorption decreased compared to the As(III) only system. These effects were similar at low and high As(III) concentrations (20 and 240 μg/mL, respectively) and at low and high pH (7.2 and 9.2). Adsorption in single element systems was well-modeled using Freundlich theory (R2 ≥ 0.92). For As: log qe = 0.521 log Ce − 0.064; Kf = 1.066, 1/n = 0.52. For Sb: log qe = 0.703 log Ce − 0.258; Kf = 0.552, 1/n = 0.70. The equation and constants determined for As(III) agree well with previous work, while those determined for Sb(III) are the first published. However, these equations do not fit for the binary systems, suggesting that other processes become important. This may be explained by the higher pH of As-containing solutions, leading to changes in both the speciation of the As and Sb and the surface charge of the AA, and possible competitive behavior between Sb(III) and As(III). We suggest that the concentration of Sb in waters treated for As should be monitored and further research is required to quantify and understand the impact of low concentrations of Sb on the removal of As through adsorption. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901061x [article] Evidence of competitive adsorption of Sb(III) and As(III) on activated alumina [texte imprimé] / Florence Bullough, Auteur ; Dominik J Weiss, Auteur ; William E Dubbin, Auteur . - 2010 . - pp. 2521–2524. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2521–2524 Mots-clés : Sb(III)  As(III)  Alumina Résumé : The impact of Sb(III) on the removal of As(III) from solution with activated alumina (AA), a widely employed low cost sorbent for various types of water treatments, was assessed. Adsorption isotherms were determined for binary element systems with As/Sb concentration ratios of 5:1, 9:1, and 12:1 to mimic conditions in water treatment facilities. These were compared to those established for single element systems. There was an increase in Sb(III) adsorption in the binary system compared to the Sb(III) only system. Conversely, in binary systems, As(III) adsorption decreased compared to the As(III) only system. These effects were similar at low and high As(III) concentrations (20 and 240 μg/mL, respectively) and at low and high pH (7.2 and 9.2). Adsorption in single element systems was well-modeled using Freundlich theory (R2 ≥ 0.92). For As: log qe = 0.521 log Ce − 0.064; Kf = 1.066, 1/n = 0.52. For Sb: log qe = 0.703 log Ce − 0.258; Kf = 0.552, 1/n = 0.70. The equation and constants determined for As(III) agree well with previous work, while those determined for Sb(III) are the first published. However, these equations do not fit for the binary systems, suggesting that other processes become important. This may be explained by the higher pH of As-containing solutions, leading to changes in both the speciation of the As and Sb and the surface charge of the AA, and possible competitive behavior between Sb(III) and As(III). We suggest that the concentration of Sb in waters treated for As should be monitored and further research is required to quantify and understand the impact of low concentrations of Sb on the removal of As through adsorption. Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901061x

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HFC-134a hydrate formation kinetics during continuous gas hydrate formation with a kenics static mixer for gas separation / Hideo Tajima in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2525–2532 Titre : HFC-134a hydrate formation kinetics during continuous gas hydrate formation with a kenics static mixer for gas separation Type de document : texte imprimé Auteurs : Hideo Tajima, Auteur ; Toru Nagata, Auteur ; Yutaka Abe, Auteur Année de publication : 2010 Article en page(s) : pp. 2525–2532 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : HFC-134  Gas Résumé : Gas hydrate formation kinetics were investigated in a Kenics static mixer. When operated under thermodynamic conditions (pressure or temperature), the hydrate formation rate increased and the HFC-134a gas bubble was covered with a hydrate “shell”. This hydrate shell inhibited hydrate growth because of resistance to mass transfer. Water recycling in the hydrate reactor accelerated hydrate formation by increasing the gas−water interface during water−gas cocurrent flow and causing the continued presence of a fresh interface in the counterflow. The kinetic data indicated that the hydrate formation rate would be equal to the mass transfer rate including the rate of hydrate shedding from the gas bubble. Enriched HFC-134a gas could be continuously recovered from an HFC-134a-nitrogen mixture in a continuous hydrate formation system. The hydrate formation rate constant for the mixed gas depended on the feed gas components Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901613h [article] HFC-134a hydrate formation kinetics during continuous gas hydrate formation with a kenics static mixer for gas separation [texte imprimé] / Hideo Tajima, Auteur ; Toru Nagata, Auteur ; Yutaka Abe, Auteur . - 2010 . - pp. 2525–2532. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2525–2532 Mots-clés : HFC-134  Gas Résumé : Gas hydrate formation kinetics were investigated in a Kenics static mixer. When operated under thermodynamic conditions (pressure or temperature), the hydrate formation rate increased and the HFC-134a gas bubble was covered with a hydrate “shell”. This hydrate shell inhibited hydrate growth because of resistance to mass transfer. Water recycling in the hydrate reactor accelerated hydrate formation by increasing the gas−water interface during water−gas cocurrent flow and causing the continued presence of a fresh interface in the counterflow. The kinetic data indicated that the hydrate formation rate would be equal to the mass transfer rate including the rate of hydrate shedding from the gas bubble. Enriched HFC-134a gas could be continuously recovered from an HFC-134a-nitrogen mixture in a continuous hydrate formation system. The hydrate formation rate constant for the mixed gas depended on the feed gas components Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901613h

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A simple and environmentally benign method for sulfoxidation of sulfides with hydrogen peroxide / Liu Fenglan in Industrial & engineering chemistry research, Vol. 49 N° 5 (Mars 2010)  

Public ISBD [article]  inIndustrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2533–2536 Titre : A simple and environmentally benign method for sulfoxidation of sulfides with hydrogen peroxide Type de document : texte imprimé Auteurs : Liu Fenglan, Auteur ; Fu Zaihui, Auteur ; Liu Yachun, Auteur Année de publication : 2010 Article en page(s) : pp. 2533–2536 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Hydrogen Peroxide  sulfides Résumé : The development of a simple, efficient, and environmentally benign method for the sulfoxidation of sulfides with aqueous hydrogen peroxide is of importance for the large-scale industrial production of sulfoxides. This article first discloses that various aryl and alkyl sulfides, without help of any catalyst and extra solvent, can be directly oxidized by 30% aqueous hydrogen peroxide to the corresponding sulfoxides with good to excellent yield at 60 °C. Furthermore, the present method has outstanding advantages, with regard to reaction rate and sulfoxide yield, compared with a series of organic solvents-mediated reactions Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9017572 [article] A simple and environmentally benign method for sulfoxidation of sulfides with hydrogen peroxide [texte imprimé] / Liu Fenglan, Auteur ; Fu Zaihui, Auteur ; Liu Yachun, Auteur . - 2010 . - pp. 2533–2536. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 5 (Mars 2010) . - pp. 2533–2536 Mots-clés : Hydrogen Peroxide  sulfides Résumé : The development of a simple, efficient, and environmentally benign method for the sulfoxidation of sulfides with aqueous hydrogen peroxide is of importance for the large-scale industrial production of sulfoxides. This article first discloses that various aryl and alkyl sulfides, without help of any catalyst and extra solvent, can be directly oxidized by 30% aqueous hydrogen peroxide to the corresponding sulfoxides with good to excellent yield at 60 °C. Furthermore, the present method has outstanding advantages, with regard to reaction rate and sulfoxide yield, compared with a series of organic solvents-mediated reactions Note de contenu : Bibliogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9017572

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