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Advances in the Correlation of Thermodynamic properties of binary systems applied to methanol mixtures with butyl esters / Fernando Espiau in Industrial & engineering chemistry research, Vol. 49 N° 19 (Octobre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 19 (Octobre 2010) . - pp. 9548-9558 Titre : Advances in the Correlation of Thermodynamic properties of binary systems applied to methanol mixtures with butyl esters Type de document : texte imprimé Auteurs : Fernando Espiau, Auteur ; Juan Ortega, Auteur ; Eduvigis Penco, Auteur Année de publication : 2010 Article en page(s) : pp. 9548-9558 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Binary  system  Thermodynamic  properties  Correlation  analysis  Correlation Résumé : This work analyzes the utility of a new model to correlate thermodynamic properties of solutions, the foundations of which have been published in a previous study. The model is applied to a set of experimental data for several properties of binary systems of methanol with four butyl alkanoates (vapor-liquid equilibria at p = 141.32 kPa and excess enthalpies and volumes at 298.15 and 318.15 K). Vapor-liquid equilibrium data (VLE) indicate that the four binary systems deviate positively from Raoult's law and do not present azeotrope. Excess enthalpies (hE) are positive for the entire range of compositions and decrease regularly with increasing length of the ester chain, with (∂hE/∂T)p,x > 0. The excess volumes (υE) decrease regularly with the length of the acid chain; they are positive for the binary systems of methanol with butyl (methanoate, ethanoate, and propanoate) and become negative for the system with butyl butanoate, with (∂vE/∂T)p,x > 0. The new model can be used to obtain a satisfactory correlation for Gibbs function gE = gE(p, T, xi), and for its derivatives. Correlation procedures for the data are described for the stages (x, hE) → [x, gE(T)] for the isobaric data reported here and (x, vE) → [x, gE(p)] for isothermal data reported in the literature. The new method allows a better correlation than the one obtained with the classical models of Wilson, NRTL, and UNIQUAC. We also present a unique correlation of all the properties of the methanol + butyl ethanoate system in the form of an analytical expression ξ(p, T, x, y) = 0 and conclude that, on the whole, its implementation can be considered an advance in the data treatment of the properties of liquid solutions. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23289693 [article] Advances in the Correlation of Thermodynamic properties of binary systems applied to methanol mixtures with butyl esters [texte imprimé] / Fernando Espiau, Auteur ; Juan Ortega, Auteur ; Eduvigis Penco, Auteur . - 2010 . - pp. 9548-9558. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 19 (Octobre 2010) . - pp. 9548-9558 Mots-clés : Binary  system  Thermodynamic  properties  Correlation  analysis  Correlation Résumé : This work analyzes the utility of a new model to correlate thermodynamic properties of solutions, the foundations of which have been published in a previous study. The model is applied to a set of experimental data for several properties of binary systems of methanol with four butyl alkanoates (vapor-liquid equilibria at p = 141.32 kPa and excess enthalpies and volumes at 298.15 and 318.15 K). Vapor-liquid equilibrium data (VLE) indicate that the four binary systems deviate positively from Raoult's law and do not present azeotrope. Excess enthalpies (hE) are positive for the entire range of compositions and decrease regularly with increasing length of the ester chain, with (∂hE/∂T)p,x > 0. The excess volumes (υE) decrease regularly with the length of the acid chain; they are positive for the binary systems of methanol with butyl (methanoate, ethanoate, and propanoate) and become negative for the system with butyl butanoate, with (∂vE/∂T)p,x > 0. The new model can be used to obtain a satisfactory correlation for Gibbs function gE = gE(p, T, xi), and for its derivatives. Correlation procedures for the data are described for the stages (x, hE) → [x, gE(T)] for the isobaric data reported here and (x, vE) → [x, gE(p)] for isothermal data reported in the literature. The new method allows a better correlation than the one obtained with the classical models of Wilson, NRTL, and UNIQUAC. We also present a unique correlation of all the properties of the methanol + butyl ethanoate system in the form of an analytical expression ξ(p, T, x, y) = 0 and conclude that, on the whole, its implementation can be considered an advance in the data treatment of the properties of liquid solutions. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23289693

Liquid – liquid equilibria in binary solutions formed by [Pyridinium - Derived] [F4B] ionic liquids and alkanols / Fernando Espiau in Industrial & engineering chemistry research, Vol. 50 N° 21 (Novembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 21 (Novembre 2011) . - pp. 12259-12270 Titre : Liquid – liquid equilibria in binary solutions formed by [Pyridinium - Derived] [F4B] ionic liquids and alkanols : new experimental data and validation of a multiparametric model for correlating LLE data Type de document : texte imprimé Auteurs : Fernando Espiau, Auteur ; Juan Ortega, Auteur ; Luís Fernández, Auteur Année de publication : 2011 Article en page(s) : pp. 12259-12270 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Modeling  Ionic  liquid  Phase  equilibrium  Liquid  liquid  equilibrium Résumé : Experimental solubility data are presented for a set of binary systems composed of ionic liquids (IL) derived from pyridium, with the tetrafluoroborate anion, ana normal alcohols ranging from ethanol to decanol, in me temperature interval of 275-420 K, at atmospheric pressure. For each case, the miscibility curve and the upper critical solubility temperature (UCST) values are presented. The effects of the ILs on the behavior of solutions with alkanols are analyzed, paying special attention to the pyridine derivatives, and considering a series of structural characteristics of the compounds involved. Miscibility curves are modeled using, for the first time in a LLE study, an adimensional form of a semiempirical model proposed for the Gibbs excess function, GE = GE(p,Trx) [Ind. Eng. Chem. Res. 2010, 49, 406], whose particular form in this work is gE(T,x)=z(x)[1-z(x)] r∑i=0 gi(T)zi(x) The results are compared with those of an extended form of the Non-Random Two-Liquids (NRTL) equation, using temperature-dependent parameters. In both cases, a rigorous procedure is carried out to calculate the LLE data, considering the isoactivity criteria, and a global test to check the phase stability for the solutions studied. The final evaluation of the application with the new equation gave satisfactory results. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24697545 [article] Liquid – liquid equilibria in binary solutions formed by [Pyridinium - Derived] [F4B] ionic liquids and alkanols : new experimental data and validation of a multiparametric model for correlating LLE data [texte imprimé] / Fernando Espiau, Auteur ; Juan Ortega, Auteur ; Luís Fernández, Auteur . - 2011 . - pp. 12259-12270. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 21 (Novembre 2011) . - pp. 12259-12270 Mots-clés : Modeling  Ionic  liquid  Phase  equilibrium  Liquid  liquid  equilibrium Résumé : Experimental solubility data are presented for a set of binary systems composed of ionic liquids (IL) derived from pyridium, with the tetrafluoroborate anion, ana normal alcohols ranging from ethanol to decanol, in me temperature interval of 275-420 K, at atmospheric pressure. For each case, the miscibility curve and the upper critical solubility temperature (UCST) values are presented. The effects of the ILs on the behavior of solutions with alkanols are analyzed, paying special attention to the pyridine derivatives, and considering a series of structural characteristics of the compounds involved. Miscibility curves are modeled using, for the first time in a LLE study, an adimensional form of a semiempirical model proposed for the Gibbs excess function, GE = GE(p,Trx) [Ind. Eng. Chem. Res. 2010, 49, 406], whose particular form in this work is gE(T,x)=z(x)[1-z(x)] r∑i=0 gi(T)zi(x) The results are compared with those of an extended form of the Non-Random Two-Liquids (NRTL) equation, using temperature-dependent parameters. In both cases, a rigorous procedure is carried out to calculate the LLE data, considering the isoactivity criteria, and a global test to check the phase stability for the solutions studied. The final evaluation of the application with the new equation gave satisfactory results. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24697545

New parametric model to correlate the gibbs excess function and other thermodynamic properties of multicomponent systems / Juan Ortega in Industrial & engineering chemistry research, Vol. 49 N° 1 (Janvier 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 1 (Janvier 2010) . - pp. 406–421 Titre : New parametric model to correlate the gibbs excess function and other thermodynamic properties of multicomponent systems : application to binary systems Type de document : texte imprimé Auteurs : Juan Ortega, Auteur ; Fernando Espiau, Auteur Année de publication : 2010 Article en page(s) : pp. 406–421 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Parametric--Correlate--Gibbs  Excess--Function--Thermodynamic--Multicomponent--Systems--Application--Binary  Systems Résumé : A new empirical mathematical model for the Gibbs excess function, gE = ψ(p,T,x), is presented for a multicomponent system. Dependence on the composition is achieved through the so-called active fraction, zi, which, in turn, is related to the molar fraction xi of the components of a solution and a parameter kij, the determination of which is also indicated. The efficacy of the model in relation to its extension of application is discussed, considering various cases and three possible ways to calculate the parameter kij. This produces different versions of the model for data correlation the advantages of which are discussed. The model proposed for the Gibbs excess function adopts the following generic expression, gE(P,T,x) = z(x)[1 − z(x)]∑i=0gi(P,T)zi where gi(P,T) = gi1 + gi2P2 + gi3PT + gi4/T + gi5T2, which can be applied to a general case of vapor−liquid equilibrium with variation of the three main variables xi, p, and T, or by considering the experimental values for two important situations, isobaric and isothermal, which are also studied here. Other mixing properties are obtained via mathematical derivation, and a simultaneous correlation is carried out on several of them. The model has been applied to various binary systems for which experimental data are available in the literature and over a wide range of p and T. The results obtained can be considered acceptable. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900898t [article] New parametric model to correlate the gibbs excess function and other thermodynamic properties of multicomponent systems : application to binary systems [texte imprimé] / Juan Ortega, Auteur ; Fernando Espiau, Auteur . - 2010 . - pp. 406–421. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 1 (Janvier 2010) . - pp. 406–421 Mots-clés : Parametric--Correlate--Gibbs  Excess--Function--Thermodynamic--Multicomponent--Systems--Application--Binary  Systems Résumé : A new empirical mathematical model for the Gibbs excess function, gE = ψ(p,T,x), is presented for a multicomponent system. Dependence on the composition is achieved through the so-called active fraction, zi, which, in turn, is related to the molar fraction xi of the components of a solution and a parameter kij, the determination of which is also indicated. The efficacy of the model in relation to its extension of application is discussed, considering various cases and three possible ways to calculate the parameter kij. This produces different versions of the model for data correlation the advantages of which are discussed. The model proposed for the Gibbs excess function adopts the following generic expression, gE(P,T,x) = z(x)[1 − z(x)]∑i=0gi(P,T)zi where gi(P,T) = gi1 + gi2P2 + gi3PT + gi4/T + gi5T2, which can be applied to a general case of vapor−liquid equilibrium with variation of the three main variables xi, p, and T, or by considering the experimental values for two important situations, isobaric and isothermal, which are also studied here. Other mixing properties are obtained via mathematical derivation, and a simultaneous correlation is carried out on several of them. The model has been applied to various binary systems for which experimental data are available in the literature and over a wide range of p and T. The results obtained can be considered acceptable. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900898t

Thermodynamic analysis of systems formed by alkyl esters with a - w alkyl dibromides / Ana Navas in Industrial & engineering chemistry research, Vol. 49 N° 24 (Décembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 24 (Décembre 2010) . - pp. 12726–12739 Titre : Thermodynamic analysis of systems formed by alkyl esters with a - w alkyl dibromides : new experimental information and the use of a dense database to describe their behavior using the UNIFAC group contribution method and the COSMO - RS methodology Type de document : texte imprimé Auteurs : Ana Navas, Auteur ; Juan Ortega, Auteur ; Tomas Martin, Auteur Année de publication : 2011 Article en page(s) : pp. 12726–12739 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Thermodynamic Résumé : This is a theoretical study carried out on the experimental data obtained for 90 binary systems comprised of alkyl esters with dibromoalkanes, using data from previous publications and those corresponding to 20 mixtures presented here. The experimental part of this work corresponds to experimental measurements of HmE and VmE at T = 298.15 K and atmospheric pressure for systems containing propyl alkanoates (methanoate to butanoate) with 1,ω-dibromoalkanes (ω = 2−6). The systems containing propyl methanoate present HmE > 0, while the remaining ones give values of HmE that follow a sigmoid distribution. The VmE of these mixtures of propyl esters are either positive or negative, depending on the dihalide involved. Positive ones correspond to mixtures with short-chain dibromoalkanes, and contraction effects are observed with the increasing chain length of the dihalide compound. On the whole, experimental information suggests a specific behavior with either positive or negative structural mixing effects depending on the chain length of the compounds. HmE values were estimated theoretically by applying two different types of models. The UNIFAC group contribution model gives good results in the prediction, but only when the Br, Br/carboxylate interaction is considered to vary with the chains of the ester and dibromoalkane; mathematical expressions are presented to describe these variations for the entire set of mixtures. The COSMO-RS quantum-chemical method is also applied to predict HmE values for the systems studied and the results extrapolated to a set of 90 systems (alkyl alkanoates + dibromoalkane), optimizing the model parameters, especially to obtain an adequate description of the Van der Waals interactions. As a result, the optimized COSMO-RS method can be used to interpret the behavior of the HmE for the whole group of alkyl esters + dibromoalkane in terms of the different intermolecular interactions taking place inside the pure compounds and mixtures, especially in relation to the variable effects of the alkyl chains of the components on the mixing enthalpies. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101479v [article] Thermodynamic analysis of systems formed by alkyl esters with a - w alkyl dibromides : new experimental information and the use of a dense database to describe their behavior using the UNIFAC group contribution method and the COSMO - RS methodology [texte imprimé] / Ana Navas, Auteur ; Juan Ortega, Auteur ; Tomas Martin, Auteur . - 2011 . - pp. 12726–12739. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 24 (Décembre 2010) . - pp. 12726–12739 Mots-clés : Thermodynamic Résumé : This is a theoretical study carried out on the experimental data obtained for 90 binary systems comprised of alkyl esters with dibromoalkanes, using data from previous publications and those corresponding to 20 mixtures presented here. The experimental part of this work corresponds to experimental measurements of HmE and VmE at T = 298.15 K and atmospheric pressure for systems containing propyl alkanoates (methanoate to butanoate) with 1,ω-dibromoalkanes (ω = 2−6). The systems containing propyl methanoate present HmE > 0, while the remaining ones give values of HmE that follow a sigmoid distribution. The VmE of these mixtures of propyl esters are either positive or negative, depending on the dihalide involved. Positive ones correspond to mixtures with short-chain dibromoalkanes, and contraction effects are observed with the increasing chain length of the dihalide compound. On the whole, experimental information suggests a specific behavior with either positive or negative structural mixing effects depending on the chain length of the compounds. HmE values were estimated theoretically by applying two different types of models. The UNIFAC group contribution model gives good results in the prediction, but only when the Br, Br/carboxylate interaction is considered to vary with the chains of the ester and dibromoalkane; mathematical expressions are presented to describe these variations for the entire set of mixtures. The COSMO-RS quantum-chemical method is also applied to predict HmE values for the systems studied and the results extrapolated to a set of 90 systems (alkyl alkanoates + dibromoalkane), optimizing the model parameters, especially to obtain an adequate description of the Van der Waals interactions. As a result, the optimized COSMO-RS method can be used to interpret the behavior of the HmE for the whole group of alkyl esters + dibromoalkane in terms of the different intermolecular interactions taking place inside the pure compounds and mixtures, especially in relation to the variable effects of the alkyl chains of the components on the mixing enthalpies. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101479v