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Phase equilibria of ester + alcohol systems and their description with the cubic-plus-association equation of state / Mariana B. Oliveira in Industrial & engineering chemistry research, Vol. 49 N° 7 (Avril 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 7 (Avril 2010) . - pp. 3452–3458 Titre : Phase equilibria of ester + alcohol systems and their description with the cubic-plus-association equation of state Type de document : texte imprimé Auteurs : Mariana B. Oliveira, Auteur ; Sofia I. Miguel, Auteur ; António J. Queimada, Auteur Année de publication : 2010 Article en page(s) : pp. 3452–3458 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Equilibria  Ester  Alcohol  Cubic-Plus Résumé : The knowledge and the capability to describe the phase equilibria of binary systems formed by a fatty acid ester and an alcohol are of great interest in biodiesel production, where these mixtures can be found after the transesterification unit and where they must be separated to purify the biodiesel stream and to recover the unreacted alcohol. Despite this interest, little information is available on the vapor−liquid equilibria (VLE) of fatty acid ester + alcohol systems. To overcome this lack of data, new VLE measurements of six ester + methanol/ethanol systems were carried at atmospheric pressure. This new experimental data was successfully modeled with the Cubic-Plus-Association equation of state (CPA EoS), with global average deviations of 0.5% for the bubble-point temperatures. In all cases small and temperature independent parameters were enough to adequately describe the measured data. Furthermore a constant value for the cross-association energy parameter was proposed for each alcohol system, as well as a linear correlation for the binary interaction parameter with the ester chain length, making the CPA EoS a powerful predictive model for these systems. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901470s [article] Phase equilibria of ester + alcohol systems and their description with the cubic-plus-association equation of state [texte imprimé] / Mariana B. Oliveira, Auteur ; Sofia I. Miguel, Auteur ; António J. Queimada, Auteur . - 2010 . - pp. 3452–3458. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 7 (Avril 2010) . - pp. 3452–3458 Mots-clés : Equilibria  Ester  Alcohol  Cubic-Plus Résumé : The knowledge and the capability to describe the phase equilibria of binary systems formed by a fatty acid ester and an alcohol are of great interest in biodiesel production, where these mixtures can be found after the transesterification unit and where they must be separated to purify the biodiesel stream and to recover the unreacted alcohol. Despite this interest, little information is available on the vapor−liquid equilibria (VLE) of fatty acid ester + alcohol systems. To overcome this lack of data, new VLE measurements of six ester + methanol/ethanol systems were carried at atmospheric pressure. This new experimental data was successfully modeled with the Cubic-Plus-Association equation of state (CPA EoS), with global average deviations of 0.5% for the bubble-point temperatures. In all cases small and temperature independent parameters were enough to adequately describe the measured data. Furthermore a constant value for the cross-association energy parameter was proposed for each alcohol system, as well as a linear correlation for the binary interaction parameter with the ester chain length, making the CPA EoS a powerful predictive model for these systems. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901470s