[article] in Industrial & engineering chemistry research > Vol. 48 N° 14 (Juillet 2009) . - pp. 6836–6845 Titre : | Prediction of vapor-liquid equilibrium at high pressure using a new excess free energy mixing rule coupled with the original UNIFAC method and the SRK equation of state | Type de document : | texte imprimé | Auteurs : | Zhen-hua Chen, Auteur ; Zhen Yao, Auteur ; Yan Li, Auteur | Année de publication : | 2009 | Article en page(s) : | pp. 6836–6845 | Note générale : | Chemical engineering | Langues : | Anglais (eng) | Mots-clés : | Low-pressure mixing rule UNIFAC method Soave-Redlich-Kwong equation EoS/GE predictive model | Résumé : | A new excess free energy mixing rule that employs a low-pressure reference state is proposed in this work. This new low-pressure mixing rule (LPMR), coupled with the original UNIFAC method and the Soave−Redlich−Kwong (SRK) equation of state (EoS), leads to an improved EoS/GE predictive model (LPMR−SRK model) that was applied to the high-pressure vapor−liquid phase equilibria of various systems including symmetric and asymmetric systems of n-alkanes with different gases (C2H6, C3H8, CO2, H2) and polar systems. The results are compared with those of other EoS/GE predictive models, such as the predictive Soave−Redlich−Kwong (PSRK), Chen-modified PSRK (MPSRK), volume-translated Peng−Robinson group contribution equation of state (VTPR), and linear combination of the Vidal and Michelsen rules (LCVM) models. It is demonstrated that LPMR−SRK method gives similar accuracy as the PSRK approach for symmetric or slightly asymmetric systems and gives better results than the MPSRK, VTPR, and LCVM models. For highly asymmetric nonpolar systems, the results indicate that the LPMR−SRK method has an accuracy similar to or slightly better than that of the MPSRK and VTPR models and gives a much better performance than the PSRK model. Furthermore, the LPMR−SRK approach is competitive with or better than the LCVM approach, except for some CO2/heavy alkane systems. In addition, although it is slightly inferior to the PSRK and LCVM approaches, the LPMR−SRK method can still provide satisfactory descriptions of polar systems that are more accurate than those of the MPSRK and VTPR models. Moreover, three ternary and one quaternary systems can also be predicted successfully by the LPMR−SRK method. | En ligne : | http://pubs.acs.org/doi/abs/10.1021/ie900111h |
[article] Prediction of vapor-liquid equilibrium at high pressure using a new excess free energy mixing rule coupled with the original UNIFAC method and the SRK equation of state [texte imprimé] / Zhen-hua Chen, Auteur ; Zhen Yao, Auteur ; Yan Li, Auteur . - 2009 . - pp. 6836–6845. Chemical engineering Langues : Anglais ( eng) in Industrial & engineering chemistry research > Vol. 48 N° 14 (Juillet 2009) . - pp. 6836–6845 Mots-clés : | Low-pressure mixing rule UNIFAC method Soave-Redlich-Kwong equation EoS/GE predictive model | Résumé : | A new excess free energy mixing rule that employs a low-pressure reference state is proposed in this work. This new low-pressure mixing rule (LPMR), coupled with the original UNIFAC method and the Soave−Redlich−Kwong (SRK) equation of state (EoS), leads to an improved EoS/GE predictive model (LPMR−SRK model) that was applied to the high-pressure vapor−liquid phase equilibria of various systems including symmetric and asymmetric systems of n-alkanes with different gases (C2H6, C3H8, CO2, H2) and polar systems. The results are compared with those of other EoS/GE predictive models, such as the predictive Soave−Redlich−Kwong (PSRK), Chen-modified PSRK (MPSRK), volume-translated Peng−Robinson group contribution equation of state (VTPR), and linear combination of the Vidal and Michelsen rules (LCVM) models. It is demonstrated that LPMR−SRK method gives similar accuracy as the PSRK approach for symmetric or slightly asymmetric systems and gives better results than the MPSRK, VTPR, and LCVM models. For highly asymmetric nonpolar systems, the results indicate that the LPMR−SRK method has an accuracy similar to or slightly better than that of the MPSRK and VTPR models and gives a much better performance than the PSRK model. Furthermore, the LPMR−SRK approach is competitive with or better than the LCVM approach, except for some CO2/heavy alkane systems. In addition, although it is slightly inferior to the PSRK and LCVM approaches, the LPMR−SRK method can still provide satisfactory descriptions of polar systems that are more accurate than those of the MPSRK and VTPR models. Moreover, three ternary and one quaternary systems can also be predicted successfully by the LPMR−SRK method. | En ligne : | http://pubs.acs.org/doi/abs/10.1021/ie900111h |
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