Documents disponibles écrits par cet auteur

Isoconversional kinetic analysis of complex solid-state processes / Junmeng Cai 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. 16157-16161 Titre : Isoconversional kinetic analysis of complex solid-state processes : Parallel and successive reactions Type de document : texte imprimé Auteurs : Junmeng Cai, Auteur ; Weixuan Wu, Auteur ; Ronghou Liu, Auteur Année de publication : 2013 Article en page(s) : pp. 16157-16161 Note générale : Industrial chemistry Langues : Anglais (eng) Résumé : A critical study of the use of the iterative linear integral isoconversional method for a parallel reactions process and a successive reactions process has been performed using theoretical simulated nonisothermal data. The activation energies obtained for these complex processes show a strong dependence on the range of heating rates, which is against the assumptions of isoconversional methods. Therefore, a systematic kinetic analysis for discriminating the reactions rather than merely assuming that the activation energy varies with the conversion would be required for understanding the reaction mechanism of these processes. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26732141 [article] Isoconversional kinetic analysis of complex solid-state processes : Parallel and successive reactions [texte imprimé] / Junmeng Cai, Auteur ; Weixuan Wu, Auteur ; Ronghou Liu, Auteur . - 2013 . - pp. 16157-16161. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 49 (Décembre 2012) . - pp. 16157-16161 Résumé : A critical study of the use of the iterative linear integral isoconversional method for a parallel reactions process and a successive reactions process has been performed using theoretical simulated nonisothermal data. The activation energies obtained for these complex processes show a strong dependence on the range of heating rates, which is against the assumptions of isoconversional methods. Therefore, a systematic kinetic analysis for discriminating the reactions rather than merely assuming that the activation energy varies with the conversion would be required for understanding the reaction mechanism of these processes. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26732141

Kinetic analysis of solid-state reactions / Junmeng Cai in Industrial & engineering chemistry research, Vol. 48 N° 6 (Mars 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 6 (Mars 2009) . - pp. 3249–3253 Titre : Kinetic analysis of solid-state reactions : a general empirical kinetic model Type de document : texte imprimé Auteurs : Junmeng Cai, Auteur ; Ronghou Liu, Auteur Année de publication : 2009 Article en page(s) : pp. 3249–3253 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Empirical  kinetic  model  Heterogeneities  Solid-state-reactions Résumé : In this research note, we presented a general empirical kinetic model that can fit any ideal kinetic model and even deviations produced by heterogeneities in particle shapes. The algebraic expression of the general empirical kinetic model is f(α) = αm(1 − qα)n. The kinetic model can be used for performing the kinetic analysis of experimental data without previous assumptions about the form of the reaction kinetic model. The empirical kinetic model has been evaluated from the theoretical and experimental data. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8018615 [article] Kinetic analysis of solid-state reactions : a general empirical kinetic model [texte imprimé] / Junmeng Cai, Auteur ; Ronghou Liu, Auteur . - 2009 . - pp. 3249–3253. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 6 (Mars 2009) . - pp. 3249–3253 Mots-clés : Empirical  kinetic  model  Heterogeneities  Solid-state-reactions Résumé : In this research note, we presented a general empirical kinetic model that can fit any ideal kinetic model and even deviations produced by heterogeneities in particle shapes. The algebraic expression of the general empirical kinetic model is f(α) = αm(1 − qα)n. The kinetic model can be used for performing the kinetic analysis of experimental data without previous assumptions about the form of the reaction kinetic model. The empirical kinetic model has been evaluated from the theoretical and experimental data. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8018615

Kinetic analysis of wheat straw oxidative pyrolysis using thermogravimetric analysis: statistical description and isoconversional kinetic analysis / Junmeng Cai in Industrial & engineering chemistry research, Vol. 48 N°2 (Janvier 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N°2 (Janvier 2009) . - p. 619–624 Titre : Kinetic analysis of wheat straw oxidative pyrolysis using thermogravimetric analysis: statistical description and isoconversional kinetic analysis Type de document : texte imprimé Auteurs : Junmeng Cai, Auteur ; Sibinuer Alimujiang, Auteur Année de publication : 2009 Article en page(s) : p. 619–624 Note générale : chemical engineering Langues : Anglais (eng) Mots-clés : Kinetic  Analysis Résumé : The oxidative pyrolysis kinetics of wheat straw was studied by thermogravimetric analysis (TGA) under oxygen dynamic atmosphere. Nonisothermal TGA data at three heating rates of 5, 10, and 20 K min−1 were analyzed. The kinetic conversion data calculated from the TGA data were fitted by the Weibull and logistic mixture models, and the corresponding statistical analyses were performed. The statistical results showed that the Weibull mixture model fitted the experimental data better than the logistic mixture model and can accurately reproduce the kinetic conversion data. Making use of the data predicted by the Weibull mixture model, some data required in the isoconversional kinetic analysis, such as α vs Tα, can be easily obtained. An iterative linear integral isoconversional method was developed and applied to evaluate the activation energy of the oxidative pyrolysis process of wheat straw. The Vyazovkin−Dollimore nonlinear integral isoconversional method was also used to calculate the activation energy. The results have shown that two isoconversional methods are equivalent for the estimation of the activation energy and the obtained activation energy is significantly dependent upon conversion for the oxidative pyrolysis process of wheat straw. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801299z [article] Kinetic analysis of wheat straw oxidative pyrolysis using thermogravimetric analysis: statistical description and isoconversional kinetic analysis [texte imprimé] / Junmeng Cai, Auteur ; Sibinuer Alimujiang, Auteur . - 2009 . - p. 619–624. chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°2 (Janvier 2009) . - p. 619–624 Mots-clés : Kinetic  Analysis Résumé : The oxidative pyrolysis kinetics of wheat straw was studied by thermogravimetric analysis (TGA) under oxygen dynamic atmosphere. Nonisothermal TGA data at three heating rates of 5, 10, and 20 K min−1 were analyzed. The kinetic conversion data calculated from the TGA data were fitted by the Weibull and logistic mixture models, and the corresponding statistical analyses were performed. The statistical results showed that the Weibull mixture model fitted the experimental data better than the logistic mixture model and can accurately reproduce the kinetic conversion data. Making use of the data predicted by the Weibull mixture model, some data required in the isoconversional kinetic analysis, such as α vs Tα, can be easily obtained. An iterative linear integral isoconversional method was developed and applied to evaluate the activation energy of the oxidative pyrolysis process of wheat straw. The Vyazovkin−Dollimore nonlinear integral isoconversional method was also used to calculate the activation energy. The results have shown that two isoconversional methods are equivalent for the estimation of the activation energy and the obtained activation energy is significantly dependent upon conversion for the oxidative pyrolysis process of wheat straw. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801299z