[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10719-10730

Titre :	A Simple algorithm for vapor – liquid – liquid equilibrium computation
Type de document :	texte imprimé
Auteurs :	P. Swapna Reddy, Auteur ; K. Yamuna Rani, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10719-10730
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Multiphase  equilibrium  Liquid  liquid  vapor  equilibrium  Algorithm
Résumé :	Calculation of phase equilibria plays a crucial part in modeling and simulation of many chemical engineering processes, and it is computationally intensive, especially for systems that exhibit two liquid phases. In this contribution, a new method to calculate the globally stable phases for systems that exhibit two liquid phases is presented which is based on iterative computation and does not require any predetermined solution set. In the proposed method, both the liquid compositions are determined with the help of a simple adaptation equation by constant times the deviation in temperatures of the two vapor phases and constant times the deviation in the corresponding vapor compositions. Convergence is evaluated based on the sum of deviation between the temperatures and vapor compositions of the two vapor phases in equilibrium with two liquid compositions, subject to the material balance constraint being satisfied. A further enhancement in convergence speed is achieved using an adaptation mechanism for updating the two constants weighing the errors. The performance of the proposed method is evaluated by computation of vapor―liquid―liquid equilibria (VLLE) for (nonreactive) mixtures encountered in five esterification reactions, in the water―toluene―aniline system and ethylene glycol―lauryl alcohol-nitromethane systems. The results obtained show that all bubble points and liquid-phase compositions of the heterogeneous mixtures and the homogeneous mixtures have been predicted accurately. The proposed method can be applied to any vapor―liquid―liquid systems common in reactive distillation systems, particularly in systems with one of the phases as an almost-pure single component.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259776

[article] A Simple algorithm for vapor – liquid – liquid equilibrium computation [texte imprimé] / P. Swapna Reddy, Auteur ; K. Yamuna Rani, Auteur . - 2012 . - pp. 10719-10730.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10719-10730

Mots-clés :	Multiphase  equilibrium  Liquid  liquid  vapor  equilibrium  Algorithm
Résumé :	Calculation of phase equilibria plays a crucial part in modeling and simulation of many chemical engineering processes, and it is computationally intensive, especially for systems that exhibit two liquid phases. In this contribution, a new method to calculate the globally stable phases for systems that exhibit two liquid phases is presented which is based on iterative computation and does not require any predetermined solution set. In the proposed method, both the liquid compositions are determined with the help of a simple adaptation equation by constant times the deviation in temperatures of the two vapor phases and constant times the deviation in the corresponding vapor compositions. Convergence is evaluated based on the sum of deviation between the temperatures and vapor compositions of the two vapor phases in equilibrium with two liquid compositions, subject to the material balance constraint being satisfied. A further enhancement in convergence speed is achieved using an adaptation mechanism for updating the two constants weighing the errors. The performance of the proposed method is evaluated by computation of vapor―liquid―liquid equilibria (VLLE) for (nonreactive) mixtures encountered in five esterification reactions, in the water―toluene―aniline system and ethylene glycol―lauryl alcohol-nitromethane systems. The results obtained show that all bubble points and liquid-phase compositions of the heterogeneous mixtures and the homogeneous mixtures have been predicted accurately. The proposed method can be applied to any vapor―liquid―liquid systems common in reactive distillation systems, particularly in systems with one of the phases as an almost-pure single component.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259776

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10712–10718

Titre :	Modeling the Cellular Uptake of Magnetofluorescent Nanoparticles in Pancreatic Cancer Cells : A Quantitative Structure Activity Relationship Study
Type de document :	texte imprimé
Auteurs :	Mehdi Ghorbanzadeh, Auteur ; Mohammad H. Fatemi, Auteur ; Masoumeh Karimpour, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10712–10718
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Nanoparticles  Modeling
Résumé :	An artificial neural network was employed to predict the cellular uptake of 109 magnetofluorescent nanoparticles (NPs) in pancreatic cancer cells on the basis of quantitative structure activity relationship method. Six descriptors chosen by combining self-organizing map and stepwise multiple linear regression (MLR) techniques were used to correlate the nanostructure of the studied particles with their bioactivity using MLR and multilayered perceptron neural network (MLP-NN) modeling techniques. For the MLR and MLP-NN models, the correlation coefficient was 0.769 and 0.934, and the root-mean-square error was 0.364 and 0.150, respectively. The results obtained after a leave-many-out cross-validation test revealed the credibility of MLP-NN for the prediction of cellular uptake of NPs. In addition, sensitivity analysis of MLP-NN model indicated that the number of hydrogen-bond donor sites in the organic coating of a NP is the predominant factor responsible for cellular uptake.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie3006947

[article] Modeling the Cellular Uptake of Magnetofluorescent Nanoparticles in Pancreatic Cancer Cells : A Quantitative Structure Activity Relationship Study [texte imprimé] / Mehdi Ghorbanzadeh, Auteur ; Mohammad H. Fatemi, Auteur ; Masoumeh Karimpour, Auteur . - 2012 . - pp. 10712–10718.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10712–10718

Mots-clés :	Nanoparticles  Modeling
Résumé :	An artificial neural network was employed to predict the cellular uptake of 109 magnetofluorescent nanoparticles (NPs) in pancreatic cancer cells on the basis of quantitative structure activity relationship method. Six descriptors chosen by combining self-organizing map and stepwise multiple linear regression (MLR) techniques were used to correlate the nanostructure of the studied particles with their bioactivity using MLR and multilayered perceptron neural network (MLP-NN) modeling techniques. For the MLR and MLP-NN models, the correlation coefficient was 0.769 and 0.934, and the root-mean-square error was 0.364 and 0.150, respectively. The results obtained after a leave-many-out cross-validation test revealed the credibility of MLP-NN for the prediction of cellular uptake of NPs. In addition, sensitivity analysis of MLP-NN model indicated that the number of hydrogen-bond donor sites in the organic coating of a NP is the predominant factor responsible for cellular uptake.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie3006947

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10702-10711

Titre :	High Performance Air Filters Produced from Freeze-Dried Fibrillated Wood Pulp : Fiber Network Compression Due to the Freezing Process
Type de document :	texte imprimé
Auteurs :	Alan L. Macfarlane, Auteur ; John F. Kadla, Auteur ; Richard J. Kerekes, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10702-10711
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Freezing  Compression  Wood  Air  filter
Résumé :	High efficiency air filters to capture submicrometer particles have been produced from fibrillated pulp fiber by a wet beating and freeze-drying procedure. Under appropriate conditions, air permeability and particle capture efficiency meeting the N95 standard can be achieved. Pulp type, beating time, and the freezing process were examined. Particle capture efficiency improved with increased beating, but excessive beating resulted in the formation of a low permeability layer (LPL). This LPL was the result of fiber network compression induced by the freezing process and formed farthest from the cold source. Adding a formation aid commonly used in paper making prevented compression of the fiber network, resulting in higher quality filters.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259774

[article] High Performance Air Filters Produced from Freeze-Dried Fibrillated Wood Pulp : Fiber Network Compression Due to the Freezing Process [texte imprimé] / Alan L. Macfarlane, Auteur ; John F. Kadla, Auteur ; Richard J. Kerekes, Auteur . - 2012 . - pp. 10702-10711.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10702-10711

Mots-clés :	Freezing  Compression  Wood  Air  filter
Résumé :	High efficiency air filters to capture submicrometer particles have been produced from fibrillated pulp fiber by a wet beating and freeze-drying procedure. Under appropriate conditions, air permeability and particle capture efficiency meeting the N95 standard can be achieved. Pulp type, beating time, and the freezing process were examined. Particle capture efficiency improved with increased beating, but excessive beating resulted in the formation of a low permeability layer (LPL). This LPL was the result of fiber network compression induced by the freezing process and formed farthest from the cold source. Adding a formation aid commonly used in paper making prevented compression of the fiber network, resulting in higher quality filters.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259774

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10695-10701

Titre :	Application of mechanochemical pretreatment prior to aqueous extraction of eleutheroside B from eleutherococcus senticosus
Type de document :	texte imprimé
Auteurs :	Liji Jin, Auteur ; Huaqiang Li, Auteur ; Feifei Wu, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10695-10701
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Pretreatment
Résumé :	A mechanochemical pretreatment was used prior to aqueous extraction of eleutheroside B from Eleutherococcus senticosus. The effects of the mechanochemical assisted extraction parameters hydroxypropyl-β-cyclodextrin (HP-β-CD) content, particle size, and circulating water temperature on the extraction yield of eleutheroside B were investigated. The mechanochemical assisted extraction process was optimized based on an orthogonal experimental design. The optimum process conditions were a HP-β-CD content of 23% (w/w), a particle size of D95 ≤ 44 μm and circulating water temperature of 40 °C. The mechanochemical assisted extraction process produced a higher eleutheroside B extraction yield, using a shorter extraction time and a greatly simplified process compared with traditional heat-reflux extraction, which makes mechanochemical assisted extraction a potential tool for eleutheroside B extraction from Eleutherococcus senticosus. Moreover, this technique used water as the solvent, making mechanochemical assisted extraction a less expensive and eco-friendly technique compared with traditional heat-reflux extraction.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259773

[article] Application of mechanochemical pretreatment prior to aqueous extraction of eleutheroside B from eleutherococcus senticosus [texte imprimé] / Liji Jin, Auteur ; Huaqiang Li, Auteur ; Feifei Wu, Auteur . - 2012 . - pp. 10695-10701.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10695-10701

Mots-clés :	Pretreatment
Résumé :	A mechanochemical pretreatment was used prior to aqueous extraction of eleutheroside B from Eleutherococcus senticosus. The effects of the mechanochemical assisted extraction parameters hydroxypropyl-β-cyclodextrin (HP-β-CD) content, particle size, and circulating water temperature on the extraction yield of eleutheroside B were investigated. The mechanochemical assisted extraction process was optimized based on an orthogonal experimental design. The optimum process conditions were a HP-β-CD content of 23% (w/w), a particle size of D95 ≤ 44 μm and circulating water temperature of 40 °C. The mechanochemical assisted extraction process produced a higher eleutheroside B extraction yield, using a shorter extraction time and a greatly simplified process compared with traditional heat-reflux extraction, which makes mechanochemical assisted extraction a potential tool for eleutheroside B extraction from Eleutherococcus senticosus. Moreover, this technique used water as the solvent, making mechanochemical assisted extraction a less expensive and eco-friendly technique compared with traditional heat-reflux extraction.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259773

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10682-10694

Titre :	Evaluation of iron (III) chelated polymer grafted lignocellulosics for arsenic (V) adsorption in a batch reactor system
Type de document :	texte imprimé
Auteurs :	S. Rijith, Auteur ; T. S. Anirudhan, Auteur ; T. Shripathi, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10682-10694
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Reactor  Batchwise  Adsorption
Résumé :	A novel adsorbent, iron(III) chelate of an amino-functionalized polyacrylamide-grafted coconut coir pith (Fe(III)-A-PGCP) was prepared and used for the removal of arsenic(V) from aqueous solutions. The adsorbent was prepared by graft copolymerization of acrylamide onto coconut coir pith, CP (a lignocellulosic residue) in the presence of N,N'-methylenebisacrylamide as a cross-linking agent followed by treatment with ethylenediamine and ferric chloride in acid (HCl) medium. The adsorbent was characterized using Fourier transform infrared (FTIR) spectroscopy, Raman analysis, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM/EDS), surface area analysis, determination of amine and iron moieties on the surface of the adsorbent, and batch adsorption experiments were carried out under a variety of operating conditions such as contact time, initial sorbate concentration, pH, adsorbent dose, presence of interfering ions, and temperature. The results showed a maximum adsorption (>99.9%) at pH 7.0. Kinetic data were modeled using pseudo-first-order, pseudo-second-order, and Ritchie-modified second-order models. The kinetic data were best described by a pseudo-second-order equation. Adsorption equilibrium data were correlated with Langmuir, Freundlich, and Sips isotherms. The results showed that the Langmuir isotherm model seemed to successfully simulate the adsorption isotherm curve and the maximum adsorption capacity was estimated to be 107.8 mg/g at 30 °C. The reusability of the spent adsorbent for several cycles was demonstrated using 0.1 M HCl. The residual arsenic concentration was brought down from 1.0 mg/L to 0.01 mg/L (more than 99.0%) was achieved with a Fe(III)-A-PGCP dose of 150 mg in a 50-mL sample. A counter-current batch adsorber was designed using operating lines.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259772

[article] Evaluation of iron (III) chelated polymer grafted lignocellulosics for arsenic (V) adsorption in a batch reactor system [texte imprimé] / S. Rijith, Auteur ; T. S. Anirudhan, Auteur ; T. Shripathi, Auteur . - 2012 . - pp. 10682-10694.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10682-10694

Mots-clés :	Reactor  Batchwise  Adsorption
Résumé :	A novel adsorbent, iron(III) chelate of an amino-functionalized polyacrylamide-grafted coconut coir pith (Fe(III)-A-PGCP) was prepared and used for the removal of arsenic(V) from aqueous solutions. The adsorbent was prepared by graft copolymerization of acrylamide onto coconut coir pith, CP (a lignocellulosic residue) in the presence of N,N'-methylenebisacrylamide as a cross-linking agent followed by treatment with ethylenediamine and ferric chloride in acid (HCl) medium. The adsorbent was characterized using Fourier transform infrared (FTIR) spectroscopy, Raman analysis, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM/EDS), surface area analysis, determination of amine and iron moieties on the surface of the adsorbent, and batch adsorption experiments were carried out under a variety of operating conditions such as contact time, initial sorbate concentration, pH, adsorbent dose, presence of interfering ions, and temperature. The results showed a maximum adsorption (>99.9%) at pH 7.0. Kinetic data were modeled using pseudo-first-order, pseudo-second-order, and Ritchie-modified second-order models. The kinetic data were best described by a pseudo-second-order equation. Adsorption equilibrium data were correlated with Langmuir, Freundlich, and Sips isotherms. The results showed that the Langmuir isotherm model seemed to successfully simulate the adsorption isotherm curve and the maximum adsorption capacity was estimated to be 107.8 mg/g at 30 °C. The reusability of the spent adsorbent for several cycles was demonstrated using 0.1 M HCl. The residual arsenic concentration was brought down from 1.0 mg/L to 0.01 mg/L (more than 99.0%) was achieved with a Fe(III)-A-PGCP dose of 150 mg in a 50-mL sample. A counter-current batch adsorber was designed using operating lines.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259772

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10671–10681

Titre :	Batch hydrolysis and rotating disk membrane bioreactor for the production of galacto - oligosaccharides : A Comparative study
Type de document :	texte imprimé
Auteurs :	Dwaipayan Sen, Auteur ; Ankur Sarkar, Auteur ; Saikat Das, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10671–10681
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Comparative  study  Production  Bioreactor  Membrane  reactor  Rotating  disk  Hydrolysis  Batchwise
Résumé :	Galactosyl-oligosaccharide (GOS) is a prebiotic carbohydrate, produced from lactose hydrolysis, that serves as a value-added functional food element for humans. Now GOS can be produced through enzymatic reaction with lactose either in batch mode or with immobilized enzyme on membrane. In the second case, the main concern is the fouling of the membrane that could reduce both the GOS yield and purity. The present study is thus an attempt to project the superiority of a membrane reactor called the rotating disk membrane bioreactor (RDMBR) over batch mode to obtain purified GOS with high yield. It was found that GOS yield and purity were 32.4% and 77% respectively in batch mode followed by diafiltration-assisted nanofiltration. However, in the immobilized state they were 67.4% and 80.2% at 105 rad s―1 membrane speed. Retention of monosaccharides that inhibit enzyme in the reaction volume of batch mode reduced the yield of GOS. On the contrary, simultaneous production and purification of GOS in RDMBR led to a high yield of GOS.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259771

[article] Batch hydrolysis and rotating disk membrane bioreactor for the production of galacto - oligosaccharides : A Comparative study [texte imprimé] / Dwaipayan Sen, Auteur ; Ankur Sarkar, Auteur ; Saikat Das, Auteur . - 2012 . - pp. 10671–10681.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10671–10681

Mots-clés :	Comparative  study  Production  Bioreactor  Membrane  reactor  Rotating  disk  Hydrolysis  Batchwise
Résumé :	Galactosyl-oligosaccharide (GOS) is a prebiotic carbohydrate, produced from lactose hydrolysis, that serves as a value-added functional food element for humans. Now GOS can be produced through enzymatic reaction with lactose either in batch mode or with immobilized enzyme on membrane. In the second case, the main concern is the fouling of the membrane that could reduce both the GOS yield and purity. The present study is thus an attempt to project the superiority of a membrane reactor called the rotating disk membrane bioreactor (RDMBR) over batch mode to obtain purified GOS with high yield. It was found that GOS yield and purity were 32.4% and 77% respectively in batch mode followed by diafiltration-assisted nanofiltration. However, in the immobilized state they were 67.4% and 80.2% at 105 rad s―1 membrane speed. Retention of monosaccharides that inhibit enzyme in the reaction volume of batch mode reduced the yield of GOS. On the contrary, simultaneous production and purification of GOS in RDMBR led to a high yield of GOS.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259771

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10659–10670

Titre :	Nonisothermal pore diffusion model for a kinetically controlled pressure swing adsorption process
Type de document :	texte imprimé
Auteurs :	Mona Khalighi, Auteur ; Shamsuzzaman Farooq, Auteur ; Iftekhar A. Karimi, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10659–10670
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Nonisothermal  Adsorption  process
Résumé :	A nonisothermal micropore diffusion model has been developed to simulate kinetically controlled pressure swing adsorption (PSA) processes. In this model, a dual-site Langmuir isotherm represents adsorption equilibrium and micropore diffusivity depends on adsorbate concentration in the solid phase according to the chemical potential gradient as the driving force for diffusion. The model has been validated with published experimental data for the kinetically controlled separation of propylene/propane on 4A zeolite. Its performance has also been extensively compared with that of a bilinear driving force (bi-LDF) model for the same system. The results clearly show that a nonisothermal micropore diffusion model with concentration-dependent diffusivity is comprehensive and complete for kinetically selective systems. The conditions under which the bi-LDF model predictions may significantly deviate from those of the pore diffusion model have also been discussed.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie3004539

[article] Nonisothermal pore diffusion model for a kinetically controlled pressure swing adsorption process [texte imprimé] / Mona Khalighi, Auteur ; Shamsuzzaman Farooq, Auteur ; Iftekhar A. Karimi, Auteur . - 2012 . - pp. 10659–10670.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10659–10670

Mots-clés :	Nonisothermal  Adsorption  process
Résumé :	A nonisothermal micropore diffusion model has been developed to simulate kinetically controlled pressure swing adsorption (PSA) processes. In this model, a dual-site Langmuir isotherm represents adsorption equilibrium and micropore diffusivity depends on adsorbate concentration in the solid phase according to the chemical potential gradient as the driving force for diffusion. The model has been validated with published experimental data for the kinetically controlled separation of propylene/propane on 4A zeolite. Its performance has also been extensively compared with that of a bilinear driving force (bi-LDF) model for the same system. The results clearly show that a nonisothermal micropore diffusion model with concentration-dependent diffusivity is comprehensive and complete for kinetically selective systems. The conditions under which the bi-LDF model predictions may significantly deviate from those of the pore diffusion model have also been discussed.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie3004539

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10649–10658

Titre :	Exploring microcrystalline cellulose (MCC) as a green multifunctional additive (MFA) in a typical solution - grade styrene butadiene rubber (S - SBR) - based tread compound
Type de document :	texte imprimé
Auteurs :	Sanjay Kumar Bhattacharyya, Auteur ; Bhavani Shanker Parmar, Auteur ; Abhijit Chakraborty, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10649–10658
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Additive
Résumé :	Multifunctional behavior of microcrystalline cellulose (MCC) was investigated in a typical solution-grade styrene butadiene rubber (S-SBR)-based tread compound in connection with its potential as reinforcing filler as well as processing aid. Optimum physical properties were obtained when the loading of MCC was at 10% of the precipitated silica amount by substituting silica. The presence of MCC in mixes had shown reduction in Mooney viscosity. Peak-power consumption during mixing was also found lower for such mixes. Because of enhanced plasticity, it was possible to reduce aromatic oil dosage by 3 phr (equivalent to 18% of the original oil amount) to get the Mooney viscosity and physicomechanical properties comparable to those of the control compound.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259769

[article] Exploring microcrystalline cellulose (MCC) as a green multifunctional additive (MFA) in a typical solution - grade styrene butadiene rubber (S - SBR) - based tread compound [texte imprimé] / Sanjay Kumar Bhattacharyya, Auteur ; Bhavani Shanker Parmar, Auteur ; Abhijit Chakraborty, Auteur . - 2012 . - pp. 10649–10658.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10649–10658

Mots-clés :	Additive
Résumé :	Multifunctional behavior of microcrystalline cellulose (MCC) was investigated in a typical solution-grade styrene butadiene rubber (S-SBR)-based tread compound in connection with its potential as reinforcing filler as well as processing aid. Optimum physical properties were obtained when the loading of MCC was at 10% of the precipitated silica amount by substituting silica. The presence of MCC in mixes had shown reduction in Mooney viscosity. Peak-power consumption during mixing was also found lower for such mixes. Because of enhanced plasticity, it was possible to reduce aromatic oil dosage by 3 phr (equivalent to 18% of the original oil amount) to get the Mooney viscosity and physicomechanical properties comparable to those of the control compound.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259769

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10641-10648

Titre :	Isolating non - predefined sensor faults by using farthest first traversal algorithm
Type de document :	texte imprimé
Auteurs :	Umut Altinisik, Auteur ; Mehmet Yildirim, Auteur ; Kadir Erkan, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10641-10648
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Algorithm
Résumé :	In this study, we propose a knowledge-based approach for detection and isolation of predefined and nonpredehned sensor faults in fault tolerant control (FTC) of a three-tank system. Farthest first traversal algorithm (FFTA) of data mining is used for the first time for the classification of faults in a FTC system. Predefining here means that features of a fault and its effects are known before the fault is seen on the system. Therefore, if a predefined fault is detected on the system, it is isolated into a known fault duster and predefined action for that cluster can be taken to tolerate the fault. However, in a working system, there may be some other faults, which are not predefined. Those may be inaccurately isolated into available known dusters, since the clusters are determined according to predefined faults instead of non-predefined ones. In our work, we also propose a method for isolating the non-predefined faults that rearranges the clusters of predefined faults, online. In order to show the efficiency of proposed method, seven predefined and thirteen non-predefined fault scenarios are applied to a closed-loop FTC system. While three of the non-predefined faults are not accurately isolated without the proposed method, all of the faults are isolated correctly with the proposed method.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259768

[article] Isolating non - predefined sensor faults by using farthest first traversal algorithm [texte imprimé] / Umut Altinisik, Auteur ; Mehmet Yildirim, Auteur ; Kadir Erkan, Auteur . - 2012 . - pp. 10641-10648.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10641-10648

Mots-clés :	Algorithm
Résumé :	In this study, we propose a knowledge-based approach for detection and isolation of predefined and nonpredehned sensor faults in fault tolerant control (FTC) of a three-tank system. Farthest first traversal algorithm (FFTA) of data mining is used for the first time for the classification of faults in a FTC system. Predefining here means that features of a fault and its effects are known before the fault is seen on the system. Therefore, if a predefined fault is detected on the system, it is isolated into a known fault duster and predefined action for that cluster can be taken to tolerate the fault. However, in a working system, there may be some other faults, which are not predefined. Those may be inaccurately isolated into available known dusters, since the clusters are determined according to predefined faults instead of non-predefined ones. In our work, we also propose a method for isolating the non-predefined faults that rearranges the clusters of predefined faults, online. In order to show the efficiency of proposed method, seven predefined and thirteen non-predefined fault scenarios are applied to a closed-loop FTC system. While three of the non-predefined faults are not accurately isolated without the proposed method, all of the faults are isolated correctly with the proposed method.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259768

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10629-10640

Titre :	Preparation of comb - type magnetic beads by surface - initiated ATRP : Modification with nitrilotriacetate groups for removal of basic dyes
Type de document :	texte imprimé
Auteurs :	Gulay Bayramoglu, Auteur ; M. Yakup Arica, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10629-10640
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Basic  dye  Preparation
Résumé :	Magnetic poly(hydroxyethyl methacrylate-co-ethylene glycol dimethacrylate) (p(HEMA-EGDMA)) beads were synthesized via suspension polymerization. To prepare a novel core―shell type resin, the magnetic beads were grafted with poly(glycidyl methacrylate) (p(GMA)) via the surface-initiated atom transfer radical polymerization (SI-ATRP) method. The grafted p(GMA) fibrous chains on the magnetic beads were modified with nitrilotriacetate (NTA). The magnetic beads were characterized by FTIR, SEM, and VSM. The carboxyl group content of the p(HEMA-EGDMA-g-GMA)-NTA resin was found to be 9.63 mmol g―1 of beads by the potentiometric titration method. The adsorption of Crystal Violet (CV) and Methylene Blue (MB) as basic dyes by the NTA-modified magnetic beads was investigated. The influence of different experimental parameters such as pH, contact time, and temperature on the removal process was evaluated. The maximum adsorption capacity was found to be 230.1 and 197.5 mg/g for CV and MB, respectively. The adsorption process was described by the Langmuir model more correctly. Adsorption studies of CV and MB onto NTA-modified magnetic beads were also carried out in a magnetically fluidized reactor with different flow rates and initial dye concentrations.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259767

[article] Preparation of comb - type magnetic beads by surface - initiated ATRP : Modification with nitrilotriacetate groups for removal of basic dyes [texte imprimé] / Gulay Bayramoglu, Auteur ; M. Yakup Arica, Auteur . - 2012 . - pp. 10629-10640.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10629-10640

Mots-clés :	Basic  dye  Preparation
Résumé :	Magnetic poly(hydroxyethyl methacrylate-co-ethylene glycol dimethacrylate) (p(HEMA-EGDMA)) beads were synthesized via suspension polymerization. To prepare a novel core―shell type resin, the magnetic beads were grafted with poly(glycidyl methacrylate) (p(GMA)) via the surface-initiated atom transfer radical polymerization (SI-ATRP) method. The grafted p(GMA) fibrous chains on the magnetic beads were modified with nitrilotriacetate (NTA). The magnetic beads were characterized by FTIR, SEM, and VSM. The carboxyl group content of the p(HEMA-EGDMA-g-GMA)-NTA resin was found to be 9.63 mmol g―1 of beads by the potentiometric titration method. The adsorption of Crystal Violet (CV) and Methylene Blue (MB) as basic dyes by the NTA-modified magnetic beads was investigated. The influence of different experimental parameters such as pH, contact time, and temperature on the removal process was evaluated. The maximum adsorption capacity was found to be 230.1 and 197.5 mg/g for CV and MB, respectively. The adsorption process was described by the Langmuir model more correctly. Adsorption studies of CV and MB onto NTA-modified magnetic beads were also carried out in a magnetically fluidized reactor with different flow rates and initial dye concentrations.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259767

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10621-10628

Titre :	Mechanism of fiber formation in melt blowing
Type de document :	texte imprimé
Auteurs :	Sanfa Xin, Auteur ; Xinhou Wang, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10621-10628
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Fiber
Résumé :	This article describes the study of the mechanism of fiber microformation in melt blowing. Through theory analysis of the flow field of molten polymers, it is inferred that the molten polymer flows in the form of the collective motion as a unit of microlayer. There is a sliding motion between every two adjacent microlayer units, and the attenuation mechanism of the fiber formation involves different microlayers that are arranged in a longer length than that before the fiber is drawn along the axial direction in terms of their velocities. Melt blowing experiments and comparison experiments were designed and performed. After measurements of the fibers and the analysis of the experimental data, results were obtained. These results verify the inference from the principle of the shear flow and the mechanism of the fiber microformation. When the theory of the formation mechanism is used to explain the fiber tenacity, by inference the tenacity of MB fiber is lower than that of spunbond or melt spinning fiber.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie300861p

[article] Mechanism of fiber formation in melt blowing [texte imprimé] / Sanfa Xin, Auteur ; Xinhou Wang, Auteur . - 2012 . - pp. 10621-10628.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10621-10628

Mots-clés :	Fiber
Résumé :	This article describes the study of the mechanism of fiber microformation in melt blowing. Through theory analysis of the flow field of molten polymers, it is inferred that the molten polymer flows in the form of the collective motion as a unit of microlayer. There is a sliding motion between every two adjacent microlayer units, and the attenuation mechanism of the fiber formation involves different microlayers that are arranged in a longer length than that before the fiber is drawn along the axial direction in terms of their velocities. Melt blowing experiments and comparison experiments were designed and performed. After measurements of the fibers and the analysis of the experimental data, results were obtained. These results verify the inference from the principle of the shear flow and the mechanism of the fiber microformation. When the theory of the formation mechanism is used to explain the fiber tenacity, by inference the tenacity of MB fiber is lower than that of spunbond or melt spinning fiber.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie300861p

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10613-10620

Titre :	Promoting effect of graphene on dye - sensitized solar cells
Type de document :	texte imprimé
Auteurs :	Hui Wang, Auteur ; Samantha L Leonard, Auteur ; Yun Hang Hu, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10613-10620
Langues :	Anglais (eng)
Mots-clés :	Dyes
Résumé :	In this paper, a simple approach without a prereduction of graphene oxide was exploited to prepare a graphene-doped TiO2 film for dye-sensitized solar cells (DSSCs). The performance measurement of the DSSCs showed that the incorporation of graphene could increase the short-circuit current density and power conversion efficiency by 52.4 and 55.3%, respectively. Furthermore, it was demonstrated that the performance enhancement was due to the promoting effect of graphene on electron transfer instead of the increase of dye loading in TiO2/graphene composite films. However, graphene can also absorb solar light, which could lead to the decrease of light harvest of dye molecules and thus a negative effect on the power conversion efficiency of DSSCs. Furthermore, graphene might decrease the actual dye loading on TiO2 in a TiO2/graphene film, which can also make a negative contribution to the conversion efficiency. As a result, the promoting effect of graphene is strongly dependent on its content; namely, the efficiency of DSSCs increases to the maximum value and then decreases with increasing graphene content in TiO2/graphene composites.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259765

[article] Promoting effect of graphene on dye - sensitized solar cells [texte imprimé] / Hui Wang, Auteur ; Samantha L Leonard, Auteur ; Yun Hang Hu, Auteur . - 2012 . - pp. 10613-10620.
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10613-10620

Mots-clés :	Dyes
Résumé :	In this paper, a simple approach without a prereduction of graphene oxide was exploited to prepare a graphene-doped TiO2 film for dye-sensitized solar cells (DSSCs). The performance measurement of the DSSCs showed that the incorporation of graphene could increase the short-circuit current density and power conversion efficiency by 52.4 and 55.3%, respectively. Furthermore, it was demonstrated that the performance enhancement was due to the promoting effect of graphene on electron transfer instead of the increase of dye loading in TiO2/graphene composite films. However, graphene can also absorb solar light, which could lead to the decrease of light harvest of dye molecules and thus a negative effect on the power conversion efficiency of DSSCs. Furthermore, graphene might decrease the actual dye loading on TiO2 in a TiO2/graphene film, which can also make a negative contribution to the conversion efficiency. As a result, the promoting effect of graphene is strongly dependent on its content; namely, the efficiency of DSSCs increases to the maximum value and then decreases with increasing graphene content in TiO2/graphene composites.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259765

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10607-10612

Titre :	Microcellular foam from ethylene vinyl acetate / polybutadiene rubber (EVA/BR) based thermoplastic elastomers for footwear applications
Type de document :	texte imprimé
Auteurs :	Madhuchhanda Maiti, Auteur ; Raksh Vir Jasra, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10607-10612
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Foam
Résumé :	Thermoplastic elastomer (TPE) from ethylene vinyl acetate (EVA) and synthetic general purpose rubber, polybutadiene rubber (BR), which can improve set, wear, and tear properties of virgin EVA without any coloring problem, was developed. EVA-BR blend ratio and processing parameters were optimized based on physicomechanical properties. It was found that EVA:BR 80:20 blend forms TPE of high strength (20 MPa) and low hardness (71 Shore A). This TPE shows 58 and 40% improvement in tension and compression set compared to virgin EVA. Tear strength and abrasion resistance of TPE was also improved by 9 and 35% respectively compared to EVA. The observed properties of TPE were explained in terms of morphology and interaction parameter. Microcellular foam of this TPE was developed using organic and inorganic blowing agents. Dinitrosopentamethylene tetramine at 3 phr loading forms closed cell microcellular foams with an average cell diameter of 100 μm. EVA:BR microcellular foam showed overall properties comparable with commercial EVA:NR microcellular foam.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259764

[article] Microcellular foam from ethylene vinyl acetate / polybutadiene rubber (EVA/BR) based thermoplastic elastomers for footwear applications [texte imprimé] / Madhuchhanda Maiti, Auteur ; Raksh Vir Jasra, Auteur . - 2012 . - pp. 10607-10612.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10607-10612

Mots-clés :	Foam
Résumé :	Thermoplastic elastomer (TPE) from ethylene vinyl acetate (EVA) and synthetic general purpose rubber, polybutadiene rubber (BR), which can improve set, wear, and tear properties of virgin EVA without any coloring problem, was developed. EVA-BR blend ratio and processing parameters were optimized based on physicomechanical properties. It was found that EVA:BR 80:20 blend forms TPE of high strength (20 MPa) and low hardness (71 Shore A). This TPE shows 58 and 40% improvement in tension and compression set compared to virgin EVA. Tear strength and abrasion resistance of TPE was also improved by 9 and 35% respectively compared to EVA. The observed properties of TPE were explained in terms of morphology and interaction parameter. Microcellular foam of this TPE was developed using organic and inorganic blowing agents. Dinitrosopentamethylene tetramine at 3 phr loading forms closed cell microcellular foams with an average cell diameter of 100 μm. EVA:BR microcellular foam showed overall properties comparable with commercial EVA:NR microcellular foam.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259764

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10595-10606

Titre :	Modeling the lignin degradation kinetics in an ethanol / formic acid solvolysis approach. Part 1. : Kinetic model development
Type de document :	texte imprimé
Auteurs :	James R. Gasson, Auteur ; Daniel Forchheim, Auteur ; Tatjana Sutter, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10595-10606
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Kinetic  model  Kinetics  Modeling
Résumé :	A formal kinetic model describing the main reaction pathways yielding demethoxylated monomeric phenols from wheat straw lignin in a hydrogen-enriched solvolysis reaction system using ethanol as cosolvent has been developed. The simplified lump model combines both a detailed focus on the deoxygenation reactions at molecular level as well as the reactions of global bulk lumps. The results show that depolymerization of lignin structures is quickly achieved and that deoxygenation reactions largely follow a main route pathway via intermediate methoxyphenols and catechols to give stable phenols in the liquid phase. Observed ethyl group substituents of phenolics are seen to originate from either alkylation reactions of the intermediates, or directly from the depolymerizing structures. A high correlation between primary 4-ethylphenol products and para-coumaryl units in the examined lignin suggests that main reaction pathways are strongly dependent on the type of plant lignin used.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259763

[article] Modeling the lignin degradation kinetics in an ethanol / formic acid solvolysis approach. Part 1. : Kinetic model development [texte imprimé] / James R. Gasson, Auteur ; Daniel Forchheim, Auteur ; Tatjana Sutter, Auteur . - 2012 . - pp. 10595-10606.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10595-10606

Mots-clés :	Kinetic  model  Kinetics  Modeling
Résumé :	A formal kinetic model describing the main reaction pathways yielding demethoxylated monomeric phenols from wheat straw lignin in a hydrogen-enriched solvolysis reaction system using ethanol as cosolvent has been developed. The simplified lump model combines both a detailed focus on the deoxygenation reactions at molecular level as well as the reactions of global bulk lumps. The results show that depolymerization of lignin structures is quickly achieved and that deoxygenation reactions largely follow a main route pathway via intermediate methoxyphenols and catechols to give stable phenols in the liquid phase. Observed ethyl group substituents of phenolics are seen to originate from either alkylation reactions of the intermediates, or directly from the depolymerizing structures. A high correlation between primary 4-ethylphenol products and para-coumaryl units in the examined lignin suggests that main reaction pathways are strongly dependent on the type of plant lignin used.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259763

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10586-10594

Titre :	Characterization and catalytic performance of deactivated and regenerated TS - 1 extrudates in a pilot plant of propene epoxidation
Type de document :	texte imprimé
Auteurs :	Yi Zuo, Auteur ; Mengli Wang, Auteur ; Wancang Song, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10586-10594
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Epoxidation  Pilot  plant  Catalytic  reaction
Résumé :	TS-1 extrudates that were used for propene epoxidation in a pilot plant for about 1700 h deactivated partly. To study the reason for the deactivation, the deactivated and regenerated catalysts were investigated with X-ray diffraction analysis, Fourier-transform infrared, Ultraviolet—visible diffuse reflectance, thermogravimetry―differential thermogravimetry, N2 sorption, n-hexane adsorption, cyclohexane adsorption, and elemental analysis. The catalytic performance of the deactivated and regenerated TS-1 extrudates in the epoxidation of propene was evaluated in a fixed-bed reactor and in a batch reactor. The activity of the deactivated catalyst from the inlet of the pilot-plant reactor was higher than that from the outlet of the reactor in which more propene oxide oligomers were generated than in the pores of catalyst taken from the inlet of the reactor. External and in situ regeneration could reinstate the activity of the deactivated catalysts, while the in situ regeneration was preferred.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259762

[article] Characterization and catalytic performance of deactivated and regenerated TS - 1 extrudates in a pilot plant of propene epoxidation [texte imprimé] / Yi Zuo, Auteur ; Mengli Wang, Auteur ; Wancang Song, Auteur . - 2012 . - pp. 10586-10594.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10586-10594

Mots-clés :	Epoxidation  Pilot  plant  Catalytic  reaction
Résumé :	TS-1 extrudates that were used for propene epoxidation in a pilot plant for about 1700 h deactivated partly. To study the reason for the deactivation, the deactivated and regenerated catalysts were investigated with X-ray diffraction analysis, Fourier-transform infrared, Ultraviolet—visible diffuse reflectance, thermogravimetry―differential thermogravimetry, N2 sorption, n-hexane adsorption, cyclohexane adsorption, and elemental analysis. The catalytic performance of the deactivated and regenerated TS-1 extrudates in the epoxidation of propene was evaluated in a fixed-bed reactor and in a batch reactor. The activity of the deactivated catalyst from the inlet of the pilot-plant reactor was higher than that from the outlet of the reactor in which more propene oxide oligomers were generated than in the pores of catalyst taken from the inlet of the reactor. External and in situ regeneration could reinstate the activity of the deactivated catalysts, while the in situ regeneration was preferred.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259762

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10571-10585

Titre :	Kinetic analysis and upper bound of ethylene yield of gas phase oxidative dehydrogenation of Ethane to Ethylene
Type de document :	texte imprimé
Auteurs :	Hassan J. Dar, Auteur ; Sandro U. Nanot, Auteur ; Klaus J. Jens, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10571-10585
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Dehydrogenation  Oxidation  Upper  bound  Kinetics
Résumé :	The gas phase oxidative dehydrogenation of ethane (ODHE) has been investigated, both experimentally and through kinetic modeling and simulation, as a potential alternative to steam cracking for ethylene production. The experiments were carried out at isothermal conditions and atmospheric pressure by using a quartz tube flow reactor (2 mm i.d.) with a volume of 0.110 mL. A gas phase kinetic model with 134 elementary reaction steps and 25 species was adopted from the literature, and the parameters were adjusted by best fitting of the experimental data based on the sensitivity analysis of the kinetic model. Further, the model was reduced based on the contribution analysis and a kinetic model of 41 steps involving 23 gas phase species was established. The kinetic analysis of the gas phase ODHE reaction is performed by means of the established kinetic model to provide the reaction pathways for ethylene and other byproducts formation, providing a better understanding of the radical chemistry for limiting the ethylene selectivity. The reactor simulations are performed under different conditions such as C2H6/O2 ratios and temperatures to search for the upper bound of the ethylene yield in the gas phase ODHE. An upper bound ethylene yield of 53.5% (C2H4 selectivity, 65.4%) is predicted at 1173 K and C2H6/O2 = 3.33 with a residence time of 0.1 s at atmospheric pressure.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259761

[article] Kinetic analysis and upper bound of ethylene yield of gas phase oxidative dehydrogenation of Ethane to Ethylene [texte imprimé] / Hassan J. Dar, Auteur ; Sandro U. Nanot, Auteur ; Klaus J. Jens, Auteur . - 2012 . - pp. 10571-10585.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10571-10585

Mots-clés :	Dehydrogenation  Oxidation  Upper  bound  Kinetics
Résumé :	The gas phase oxidative dehydrogenation of ethane (ODHE) has been investigated, both experimentally and through kinetic modeling and simulation, as a potential alternative to steam cracking for ethylene production. The experiments were carried out at isothermal conditions and atmospheric pressure by using a quartz tube flow reactor (2 mm i.d.) with a volume of 0.110 mL. A gas phase kinetic model with 134 elementary reaction steps and 25 species was adopted from the literature, and the parameters were adjusted by best fitting of the experimental data based on the sensitivity analysis of the kinetic model. Further, the model was reduced based on the contribution analysis and a kinetic model of 41 steps involving 23 gas phase species was established. The kinetic analysis of the gas phase ODHE reaction is performed by means of the established kinetic model to provide the reaction pathways for ethylene and other byproducts formation, providing a better understanding of the radical chemistry for limiting the ethylene selectivity. The reactor simulations are performed under different conditions such as C2H6/O2 ratios and temperatures to search for the upper bound of the ethylene yield in the gas phase ODHE. An upper bound ethylene yield of 53.5% (C2H4 selectivity, 65.4%) is predicted at 1173 K and C2H6/O2 = 3.33 with a residence time of 0.1 s at atmospheric pressure.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259761

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10565-10570

Titre :	Combustion characteristics of sewage sludge in a fluidized bed
Type de document :	texte imprimé
Auteurs :	Xiangxin Han, Auteur ; Mengting Niu, Auteur ; Xiumin Jiang, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10565-10570
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Fluidized  bed  Fluidization  Sewage  sludge  Combustion
Résumé :	Combustion experiments of Shidongkou sewage sludge from China were carried out by using a small lab-scale fluidized bed, and the effects of moisture content and feed rate of sewage sludge and the transfer of heavy metals were analyzed. Studied sewage sludge with a moisture content of no more than 40% can stably bum in the fluidized bed without any auxiliary fuel input. Enhancing the bed temperature of the dense phase, strengthening the gas-solid mixing of dense phase, and increasing the feed rate of sludge are very necessary for the ignition of sludge with higher moisture content; however, higher feed rate will give rise to an increase of both the incomplete combustion heat loss and the physical absorbing heat amount of new sludge into the fluidized bed, reducing the bed temperature. Gaseous pollutants from the fluidized bed were discussed under different experimental conditions. At last, it was presented that heavy metals except Zn within sewage sludge are mostly concentrated in bottom ashes and bag filter ashes.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259760

[article] Combustion characteristics of sewage sludge in a fluidized bed [texte imprimé] / Xiangxin Han, Auteur ; Mengting Niu, Auteur ; Xiumin Jiang, Auteur . - 2012 . - pp. 10565-10570.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10565-10570

Mots-clés :	Fluidized  bed  Fluidization  Sewage  sludge  Combustion
Résumé :	Combustion experiments of Shidongkou sewage sludge from China were carried out by using a small lab-scale fluidized bed, and the effects of moisture content and feed rate of sewage sludge and the transfer of heavy metals were analyzed. Studied sewage sludge with a moisture content of no more than 40% can stably bum in the fluidized bed without any auxiliary fuel input. Enhancing the bed temperature of the dense phase, strengthening the gas-solid mixing of dense phase, and increasing the feed rate of sludge are very necessary for the ignition of sludge with higher moisture content; however, higher feed rate will give rise to an increase of both the incomplete combustion heat loss and the physical absorbing heat amount of new sludge into the fluidized bed, reducing the bed temperature. Gaseous pollutants from the fluidized bed were discussed under different experimental conditions. At last, it was presented that heavy metals except Zn within sewage sludge are mostly concentrated in bottom ashes and bag filter ashes.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259760

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10557-10564

Titre :	Degradation behavior of polypropylene – organically modified clay nanocomposites
Type de document :	texte imprimé
Auteurs :	K. J. Singala, Auteur ; A. A. Mungray, Auteur ; A. K. Mungray, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10557-10564
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Nanocomposite
Résumé :	The degradation mechanism of polypropylene (PP)―clay nanocomposites is investigated in the present study. The he pp―clay nanocomposites are prepared through a solution process with 4 and 8 wt % incorporation ot nanoclay in a polymer matrix. Nanoclay with two types of organic modifications (25―30 wt % methyl dihydroxyethyl hydrogenated tallow ammonium (TA) and 25―30 wt % octadecylamine (OA)) is used with isotactic PP, atactic PP, and ethylene propylene copolymer with ∼20 wt % rubber. Characterization of nanocomposites is done through X-ray diffraction (XRD) analysis while melting and crystallization behavior is studied through differential scanning calorimetry (DSC). XRD and DSC analysis shows formation of intercalated type nanocomposites with improved barrier properties. Degradation behavior of nanocomposites is studied through thermogravimetric analysis (TGA). Weight loss curves are further analyzed through the Friedman technique to find the rate of degradation. Nanoclay incorporation increases the lifetime of nanocomposites, calculated using an equation derived by Toop [IEEE Trans. Electr. Insul. 1971, 6, 2―14]. The peak rate of degradation in nanocomposites with isotactic homo PP and ethylene propylene copolymer is found to increase up to 1.5 times. Atactic homo PP and its nanocomposites show only a marginal improvement in properties as well as degradation rate. It is also concluded that the rate of degradation increased with clay loading due to increase in residual impurity.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259759

[article] Degradation behavior of polypropylene – organically modified clay nanocomposites [texte imprimé] / K. J. Singala, Auteur ; A. A. Mungray, Auteur ; A. K. Mungray, Auteur . - 2012 . - pp. 10557-10564.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10557-10564

Mots-clés :	Nanocomposite
Résumé :	The degradation mechanism of polypropylene (PP)―clay nanocomposites is investigated in the present study. The he pp―clay nanocomposites are prepared through a solution process with 4 and 8 wt % incorporation ot nanoclay in a polymer matrix. Nanoclay with two types of organic modifications (25―30 wt % methyl dihydroxyethyl hydrogenated tallow ammonium (TA) and 25―30 wt % octadecylamine (OA)) is used with isotactic PP, atactic PP, and ethylene propylene copolymer with ∼20 wt % rubber. Characterization of nanocomposites is done through X-ray diffraction (XRD) analysis while melting and crystallization behavior is studied through differential scanning calorimetry (DSC). XRD and DSC analysis shows formation of intercalated type nanocomposites with improved barrier properties. Degradation behavior of nanocomposites is studied through thermogravimetric analysis (TGA). Weight loss curves are further analyzed through the Friedman technique to find the rate of degradation. Nanoclay incorporation increases the lifetime of nanocomposites, calculated using an equation derived by Toop [IEEE Trans. Electr. Insul. 1971, 6, 2―14]. The peak rate of degradation in nanocomposites with isotactic homo PP and ethylene propylene copolymer is found to increase up to 1.5 times. Atactic homo PP and its nanocomposites show only a marginal improvement in properties as well as degradation rate. It is also concluded that the rate of degradation increased with clay loading due to increase in residual impurity.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259759

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10546-10556

Titre :	Generation of superoxide ion in pyridinium, morpholinium, ammonium, and sulfonium - based ionic liquids and the application in the destruction of toxic chlorinated phenols
Type de document :	texte imprimé
Auteurs :	Maan Hayyan, Auteur ; Farouq S. Mjalli, Auteur ; Mohd Ali Hashim, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10546-10556
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Ionic  liquid
Résumé :	Generation of superoxide ion (O2•―) was carried out in four ionic liquids (ILs) having the same anion, bis(trifluoromethylsulfonyl)imide [N(Tf)2]―, and different cations, N-hexylpyridinium [HPy]+, N-methoxyethyl-N-methyl-morpholinium [MO1,1O2]+, N-ethyl-N,N-dimethyl-2-methoxyethylammonium [N112,1O2]+, and triethylsulfonium [S222]+. Cyclic voltammetry (CV) and chronoamperometry (CA) electrochemical techniques were used in this investigation. It was found that O2•― is not stable in the [HPy]+-based IL. On the other hand, CV showed that the electrochemically generated O2•― is stable in [MO1,1O2]+-, [N112,1O2]+-, and [S222]+-based ILs for the time duration of the experiment. The long-term stability of the generated O2•― was then investigated by dissolving potassium superoxide (KO2) in dimethyl sulfoxide (DMSO) in the presence of the corresponding IL. It was found that ILs containing [MO1,1O2]+ and [N112,1O2]+ offer a promising long-term stability of O2•― for various reactions to be used for several applications. However, it was found that after 2 h, about 92.5% of the generated O2•― in [S222]+ based IL was consumed. The diffusion coefficient and solubility of O2 in the studied ILs were then determined using CV and CA techniques simultaneously. It was found that diffusion coefficients and CA steady-state currents increase with temperature increases, while the solubility of O2 decreased. To our best knowledge, this is the first time that morpholinium and sulfoniumbased ILs were utilized as media for chemical and electrochemical generation of O2•―. Additionally, the chemically generated O2•―, by dissolving KO2, was then used for the destruction of 2,4-dichlorophenol (DCP) in [MO1,1O2][N(Tf)2] under ambient conditions. The destruction percentage was higher than 98%. This work represents a novel application of the chemically generated O2•― for the destruction of toxic chlorinated phenols in ILs media.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259758

[article] Generation of superoxide ion in pyridinium, morpholinium, ammonium, and sulfonium - based ionic liquids and the application in the destruction of toxic chlorinated phenols [texte imprimé] / Maan Hayyan, Auteur ; Farouq S. Mjalli, Auteur ; Mohd Ali Hashim, Auteur . - 2012 . - pp. 10546-10556.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10546-10556

Mots-clés :	Ionic  liquid
Résumé :	Generation of superoxide ion (O2•―) was carried out in four ionic liquids (ILs) having the same anion, bis(trifluoromethylsulfonyl)imide [N(Tf)2]―, and different cations, N-hexylpyridinium [HPy]+, N-methoxyethyl-N-methyl-morpholinium [MO1,1O2]+, N-ethyl-N,N-dimethyl-2-methoxyethylammonium [N112,1O2]+, and triethylsulfonium [S222]+. Cyclic voltammetry (CV) and chronoamperometry (CA) electrochemical techniques were used in this investigation. It was found that O2•― is not stable in the [HPy]+-based IL. On the other hand, CV showed that the electrochemically generated O2•― is stable in [MO1,1O2]+-, [N112,1O2]+-, and [S222]+-based ILs for the time duration of the experiment. The long-term stability of the generated O2•― was then investigated by dissolving potassium superoxide (KO2) in dimethyl sulfoxide (DMSO) in the presence of the corresponding IL. It was found that ILs containing [MO1,1O2]+ and [N112,1O2]+ offer a promising long-term stability of O2•― for various reactions to be used for several applications. However, it was found that after 2 h, about 92.5% of the generated O2•― in [S222]+ based IL was consumed. The diffusion coefficient and solubility of O2 in the studied ILs were then determined using CV and CA techniques simultaneously. It was found that diffusion coefficients and CA steady-state currents increase with temperature increases, while the solubility of O2 decreased. To our best knowledge, this is the first time that morpholinium and sulfoniumbased ILs were utilized as media for chemical and electrochemical generation of O2•―. Additionally, the chemically generated O2•―, by dissolving KO2, was then used for the destruction of 2,4-dichlorophenol (DCP) in [MO1,1O2][N(Tf)2] under ambient conditions. The destruction percentage was higher than 98%. This work represents a novel application of the chemically generated O2•― for the destruction of toxic chlorinated phenols in ILs media.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259758

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10542-10545

Titre :	Mordant yellow 3 anions intercalated layered double hydroxides : Preparation, thermo - and photostability
Type de document :	texte imprimé
Auteurs :	Pinggui Tang, Auteur ; Fuping Deng, Auteur ; Yongjun Feng, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10542-10545
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Hydroxides  Thermo  photostability
Résumé :	Mordant yellow 3 (MY3) anions have been intercalated into Zn-Al layered double hydroxides (LDH) to produce a novel intercalation compound pigment by a direct coprecipitation method. The prepared composite was characterized by various techniques such as powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry and differential thermal analysis (TGA-DTA), and UV–vis spectroscopy. The obtained results show that MY3 anions were intercalated into the interlayer spacing of LDH as observed from PXRD and FT-IR. Furthermore, the intercalation of MY3 anions into the LDH markedly enhances the thermo- and photostability of MY3, which may enlarge the practical application fields of MY3 dye.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie300645b

[article] Mordant yellow 3 anions intercalated layered double hydroxides : Preparation, thermo - and photostability [texte imprimé] / Pinggui Tang, Auteur ; Fuping Deng, Auteur ; Yongjun Feng, Auteur . - 2012 . - pp. 10542-10545.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10542-10545

Mots-clés :	Hydroxides  Thermo  photostability
Résumé :	Mordant yellow 3 (MY3) anions have been intercalated into Zn-Al layered double hydroxides (LDH) to produce a novel intercalation compound pigment by a direct coprecipitation method. The prepared composite was characterized by various techniques such as powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry and differential thermal analysis (TGA-DTA), and UV–vis spectroscopy. The obtained results show that MY3 anions were intercalated into the interlayer spacing of LDH as observed from PXRD and FT-IR. Furthermore, the intercalation of MY3 anions into the LDH markedly enhances the thermo- and photostability of MY3, which may enlarge the practical application fields of MY3 dye.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie300645b

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10535-10541

Titre :	Effect of Mg, Ca, and Sr on CeO2 based catalysts for the oxidative coupling of methane : Investigation on the oxygen species responsible for catalytic performance
Type de document :	texte imprimé
Auteurs :	Victor J. Ferreira, Auteur ; Pedro Tavares, Auteur ; José L. Figueiredo, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10535-10541
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Catalytic  reaction  Oxidative  coupling  Catalyst
Résumé :	CeO2 catalysts modified with earth alkaline metals (M = Mg, Ca, and Sr) were prepared by the citrate method in a M:Ce molar ratio of 1:1. Different analytical techniques including diffuse reflectance Ultraviolet―Visible (DR UV―vis) and diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and temperature programmed desorption of CO2 (TPD-CO2) were used for the characterization of the catalysts. The materials were tested in the oxidative coupling of methane (OCM). The results of calcined samples revealed that the charge transfer from cerium to oxygen ions is shifted when CeO2 is doped, indicating defects on the catalyst surface. A linear correlation was found between the amount of surface basic sites and the ratio of the oxygen species O2― and O22― to lattice oxygen. This behavior is crucial for the CH4 conversion and selectivity to C2H6 and C2H4 at 700 °C. Ca-doped CeO2 catalyst revealed the best performance in the OCM, which can be attributed to the similar ionic radii of Ca2+ and Ce4+.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259756

[article] Effect of Mg, Ca, and Sr on CeO2 based catalysts for the oxidative coupling of methane : Investigation on the oxygen species responsible for catalytic performance [texte imprimé] / Victor J. Ferreira, Auteur ; Pedro Tavares, Auteur ; José L. Figueiredo, Auteur . - 2012 . - pp. 10535-10541.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10535-10541

Mots-clés :	Catalytic  reaction  Oxidative  coupling  Catalyst
Résumé :	CeO2 catalysts modified with earth alkaline metals (M = Mg, Ca, and Sr) were prepared by the citrate method in a M:Ce molar ratio of 1:1. Different analytical techniques including diffuse reflectance Ultraviolet―Visible (DR UV―vis) and diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and temperature programmed desorption of CO2 (TPD-CO2) were used for the characterization of the catalysts. The materials were tested in the oxidative coupling of methane (OCM). The results of calcined samples revealed that the charge transfer from cerium to oxygen ions is shifted when CeO2 is doped, indicating defects on the catalyst surface. A linear correlation was found between the amount of surface basic sites and the ratio of the oxygen species O2― and O22― to lattice oxygen. This behavior is crucial for the CH4 conversion and selectivity to C2H6 and C2H4 at 700 °C. Ca-doped CeO2 catalyst revealed the best performance in the OCM, which can be attributed to the similar ionic radii of Ca2+ and Ce4+.
ISSN :	0888-5885
En ligne :	http://cat.inist.fr/?aModele=afficheN&cpsidt=26259756

[article] 
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10525-10534

Titre :	Reactions of methyl perfluoroalkyl ethers with isopropyl alcohol : Experimental and theoretical studies
Type de document :	texte imprimé
Auteurs :	Howard C. Knachel, Auteur ; Vladimir Benin, Auteur ; Chadwick D. Barklay, Auteur
Année de publication :	2012
Article en page(s) :	pp. 10525-10534
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Methyl  Isopropyl
Résumé :	The reaction of an isomeric mixture of the methyl perfluoroalkyl ether, C4F9OCH3 (Novec-7100), in the presence of isopropyl alcohol (IPA) and/or water has been studied by measuring the rate of product formation using an ion-selective electrode (ISE) for fluoride ion, Karl Fisher coulometric titrations for water, and 1H and 19F NMR spectroscopy for product identification and rate studies. The results showed the methyl perfluoroalkyl ether to be very stable with products forming at the rate of 1 ppm per year at a laboratory temperature of 20 °C. Measurements over the temperature range of 6° to 100 °C were made on samples aged for periods up to 1.8 years. Density functional theory calculations (DFT, B3LYP/6-31+G(d)) were employed to investigate different reaction pathways and formulate the probable reaction mechanism. The experimental enthalpy (ΔH) and entropy (ΔS) of activation were determined based on several different kinetic measurements. The ΔH values are in the range of 20–25 kcal/mol and the corresponding ΔS values range from −32 to −15 cal/(mol K). These are in good agreement with the theoretical values. While the range of ΔH values does not change appreciatively, the ΔS values are dependent on the proportion of vapor to liquid involved in the reaction of C4F9OCH3 with IPA so that the more vapor the more negative the ΔS value.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie2018564

[article] Reactions of methyl perfluoroalkyl ethers with isopropyl alcohol : Experimental and theoretical studies [texte imprimé] / Howard C. Knachel, Auteur ; Vladimir Benin, Auteur ; Chadwick D. Barklay, Auteur . - 2012 . - pp. 10525-10534.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10525-10534

Mots-clés :	Methyl  Isopropyl
Résumé :	The reaction of an isomeric mixture of the methyl perfluoroalkyl ether, C4F9OCH3 (Novec-7100), in the presence of isopropyl alcohol (IPA) and/or water has been studied by measuring the rate of product formation using an ion-selective electrode (ISE) for fluoride ion, Karl Fisher coulometric titrations for water, and 1H and 19F NMR spectroscopy for product identification and rate studies. The results showed the methyl perfluoroalkyl ether to be very stable with products forming at the rate of 1 ppm per year at a laboratory temperature of 20 °C. Measurements over the temperature range of 6° to 100 °C were made on samples aged for periods up to 1.8 years. Density functional theory calculations (DFT, B3LYP/6-31+G(d)) were employed to investigate different reaction pathways and formulate the probable reaction mechanism. The experimental enthalpy (ΔH) and entropy (ΔS) of activation were determined based on several different kinetic measurements. The ΔH values are in the range of 20–25 kcal/mol and the corresponding ΔS values range from −32 to −15 cal/(mol K). These are in good agreement with the theoretical values. While the range of ΔH values does not change appreciatively, the ΔS values are dependent on the proportion of vapor to liquid involved in the reaction of C4F9OCH3 with IPA so that the more vapor the more negative the ΔS value.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie2018564