Documents disponibles écrits par cet auteur

Experimental investigation of the interaction of dimethyl sulfide/ethyl mercaptan with nano-manganese dioxide / Jie He in Industrial & engineering chemistry research, Vol. 51 N° 49 (Décembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 49 (Décembre 2012) . - pp. 15912–15917 Titre : Experimental investigation of the interaction of dimethyl sulfide/ethyl mercaptan with nano-manganese dioxide Type de document : texte imprimé Auteurs : Jie He, Auteur ; Xiaotian Liu, Auteur ; Lin Li, Auteur Année de publication : 2013 Article en page(s) : pp. 15912–15917 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Nano  manganese  dioxide Résumé : Nano-MnO2 was prepared by a sol–gel technology, and the structure was characterized by means of powder X-ray diffraction (XRD). The interaction of dimethyl sulfide (DMS) or ethyl mercaptan (EM) with the as-prepared MnO2 was investigated at ambient temperature with Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and laser Raman spectroscopy (LRS). The results showed that DMS and EM undergo different interactions with the surface of MnO2. The interaction of DMS and MnO2 bring about carbon–sulfur bond cleavage and the oxidation of C. However, there might be hydrogen bonding between EM and MnO2 in addition to chemical bonding, which results in a weaker S–H bond in the EM molecule, so that EM is easily oxidized to sulfonates and sulfates. Tentative interaction mechanisms for DMS and EM on MnO2 are suggested. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie302097x [article] Experimental investigation of the interaction of dimethyl sulfide/ethyl mercaptan with nano-manganese dioxide [texte imprimé] / Jie He, Auteur ; Xiaotian Liu, Auteur ; Lin Li, Auteur . - 2013 . - pp. 15912–15917. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 49 (Décembre 2012) . - pp. 15912–15917 Mots-clés : Nano  manganese  dioxide Résumé : Nano-MnO2 was prepared by a sol–gel technology, and the structure was characterized by means of powder X-ray diffraction (XRD). The interaction of dimethyl sulfide (DMS) or ethyl mercaptan (EM) with the as-prepared MnO2 was investigated at ambient temperature with Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and laser Raman spectroscopy (LRS). The results showed that DMS and EM undergo different interactions with the surface of MnO2. The interaction of DMS and MnO2 bring about carbon–sulfur bond cleavage and the oxidation of C. However, there might be hydrogen bonding between EM and MnO2 in addition to chemical bonding, which results in a weaker S–H bond in the EM molecule, so that EM is easily oxidized to sulfonates and sulfates. Tentative interaction mechanisms for DMS and EM on MnO2 are suggested. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie302097x

On the calculation of operability sets of nonlinear high-dimensional processes / Christos Georgakis in Industrial & engineering chemistry research, Vol. 49 N° 17 (Septembre 1, 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 17 (Septembre 1, 2010) . - pp 8035–8047 Titre : On the calculation of operability sets of nonlinear high-dimensional processes Type de document : texte imprimé Auteurs : Christos Georgakis, Auteur ; Lin Li, Auteur Année de publication : 2010 Article en page(s) : pp 8035–8047 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Nonlinear  high  dimensional  processes. Résumé : The calculation of the steady state operability characteristics of nonlinear high-dimensional processes is a difficult task computationally as it involves the mapping of high-dimensional, constrained input sets through the nonlinear process model to a high-dimensional output set. The reverse mapping, from outputs to inputs, also of interest, is equally challenging. In this paper we propose the selection of a finite number of points as an adequately accurate representation of the overall input-output mapping of the detailed model. This approach is motivated by the well established design of experiments (DoE) [Montgomery, D. C. Design and Analysis of Experiments; Wiley: New York, 2005. Box, G. E. P.; Draper, N. R. Response Surfaces, Mixtures, and Ridge Analysis; Wiley: Hoboken, NJ, 2007. Box, G. E. P.; Hunter, J. S.; Hunter, W. G. Statistics for Experimenters: Design, Innovation and Discovery, 2nd ed.; John Wiley & Sons, Inc.: Hoboken, NJ, 2004.] methodology which has been successful in experimentally investigating similar relationships for processes that have not yet been modeled. For this reason, the proposed approach is called design of selective calculations (DoSC). The mapping of only selective points and the development of an interpolative response surface model for the output points enables the calculation of the desired operability sets with a much reduced number of calculations without any significant loss of accuracy. The applicability of the developed method is illustrated with two motivating examples and a plant-wide industrial process, the Tennessee Eastman challenge problem. Of particular interest is the demonstration that the response surface model with quadratic terms is rich enough to accurately describe even the complex phenomenon of input multiplicity. When input multiplicity exists, the image of the boundary of the input set does not fully describe the boundary of the image set. In such a case, mapping only the boundaries of the related sets is not sufficient. Besides its overall computational economy, the proposed method overcomes this important additional challenge. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1009316 [article] On the calculation of operability sets of nonlinear high-dimensional processes [texte imprimé] / Christos Georgakis, Auteur ; Lin Li, Auteur . - 2010 . - pp 8035–8047. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 17 (Septembre 1, 2010) . - pp 8035–8047 Mots-clés : Nonlinear  high  dimensional  processes. Résumé : The calculation of the steady state operability characteristics of nonlinear high-dimensional processes is a difficult task computationally as it involves the mapping of high-dimensional, constrained input sets through the nonlinear process model to a high-dimensional output set. The reverse mapping, from outputs to inputs, also of interest, is equally challenging. In this paper we propose the selection of a finite number of points as an adequately accurate representation of the overall input-output mapping of the detailed model. This approach is motivated by the well established design of experiments (DoE) [Montgomery, D. C. Design and Analysis of Experiments; Wiley: New York, 2005. Box, G. E. P.; Draper, N. R. Response Surfaces, Mixtures, and Ridge Analysis; Wiley: Hoboken, NJ, 2007. Box, G. E. P.; Hunter, J. S.; Hunter, W. G. Statistics for Experimenters: Design, Innovation and Discovery, 2nd ed.; John Wiley & Sons, Inc.: Hoboken, NJ, 2004.] methodology which has been successful in experimentally investigating similar relationships for processes that have not yet been modeled. For this reason, the proposed approach is called design of selective calculations (DoSC). The mapping of only selective points and the development of an interpolative response surface model for the output points enables the calculation of the desired operability sets with a much reduced number of calculations without any significant loss of accuracy. The applicability of the developed method is illustrated with two motivating examples and a plant-wide industrial process, the Tennessee Eastman challenge problem. Of particular interest is the demonstration that the response surface model with quadratic terms is rich enough to accurately describe even the complex phenomenon of input multiplicity. When input multiplicity exists, the image of the boundary of the input set does not fully describe the boundary of the image set. In such a case, mapping only the boundaries of the related sets is not sufficient. Besides its overall computational economy, the proposed method overcomes this important additional challenge. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1009316

Oxidation of 1,1,1 - trichloroethane stimulated by thermally activated persulfate / Xiaogang Gu in Industrial & engineering chemistry research, Vol. 50 N° 19 (Octobre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 19 (Octobre 2011) . - pp. 11029–11036 Titre : Oxidation of 1,1,1 - trichloroethane stimulated by thermally activated persulfate Type de document : texte imprimé Auteurs : Xiaogang Gu, Auteur ; Shuguang Lu, Auteur ; Lin Li, Auteur Année de publication : 2011 Article en page(s) : pp. 11029–11036 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Oxidation  Trichloroethane Résumé : In this study, thermally activated persulfate (PS) to stimulate the oxidation of 1,1,1-trichloroethane (TCA) in groundwater remediation was investigated. The effects of various factors including temperature; initial TCA concentration; PS/TCA molar ratio; solution pH; and common constituents in groundwater such as Cl–, HCO3–, SO42–, and NO3– anions and humic acid (HA) were evaluated. The experimental results showed that TCA can be completely oxidized in 2 h at 50 °C with a PS/TCA molar ratio of 100/1, indicating the effectiveness of thermally activated PS oxidation for TCA removal. TCA oxidation was fitted with a pseudo-first-order kinetic model, and the rate constant was found to increase with increasing temperature and PS/TCA molar ratio, but to decrease with increasing initial TCA concentration. In addition, acidic conditions were favorable to TCA removal and elevating, the initial solution pH value (from pH 3 to 11) decreased the TCA degradation rate. Anions Cl– and HCO3– had negative effects on TCA removal, whereas the effects of both SO42– and NO3– were negligible. With 5–10 mg L–1 concentrations of HA in solution, an inhibitive effect was observed, indicating that dissolved organic matter consumed some of the oxidant. However, the anticipated effective thermally activated PS oxidation of TCA in groundwater from a real contaminated site was not achieved because of the complex solution matrix. On the other hand, the TCA degradation mechanism derived from GC/MS analytical results confirmed formic acid, dichloromethane, and trichloromethane as the primary intermediates, and therefore, two TCA decomposition pathways were proposed. In conclusion, thermally activated PS oxidation is a highly promising technique for TCA-contaminated groundwater remediation, but more complex constituents in in situ groundwater should be carefully considered for its practical application. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201059x [article] Oxidation of 1,1,1 - trichloroethane stimulated by thermally activated persulfate [texte imprimé] / Xiaogang Gu, Auteur ; Shuguang Lu, Auteur ; Lin Li, Auteur . - 2011 . - pp. 11029–11036. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 19 (Octobre 2011) . - pp. 11029–11036 Mots-clés : Oxidation  Trichloroethane Résumé : In this study, thermally activated persulfate (PS) to stimulate the oxidation of 1,1,1-trichloroethane (TCA) in groundwater remediation was investigated. The effects of various factors including temperature; initial TCA concentration; PS/TCA molar ratio; solution pH; and common constituents in groundwater such as Cl–, HCO3–, SO42–, and NO3– anions and humic acid (HA) were evaluated. The experimental results showed that TCA can be completely oxidized in 2 h at 50 °C with a PS/TCA molar ratio of 100/1, indicating the effectiveness of thermally activated PS oxidation for TCA removal. TCA oxidation was fitted with a pseudo-first-order kinetic model, and the rate constant was found to increase with increasing temperature and PS/TCA molar ratio, but to decrease with increasing initial TCA concentration. In addition, acidic conditions were favorable to TCA removal and elevating, the initial solution pH value (from pH 3 to 11) decreased the TCA degradation rate. Anions Cl– and HCO3– had negative effects on TCA removal, whereas the effects of both SO42– and NO3– were negligible. With 5–10 mg L–1 concentrations of HA in solution, an inhibitive effect was observed, indicating that dissolved organic matter consumed some of the oxidant. However, the anticipated effective thermally activated PS oxidation of TCA in groundwater from a real contaminated site was not achieved because of the complex solution matrix. On the other hand, the TCA degradation mechanism derived from GC/MS analytical results confirmed formic acid, dichloromethane, and trichloromethane as the primary intermediates, and therefore, two TCA decomposition pathways were proposed. In conclusion, thermally activated PS oxidation is a highly promising technique for TCA-contaminated groundwater remediation, but more complex constituents in in situ groundwater should be carefully considered for its practical application. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201059x