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A group contribution method for heat capacity estimation of ionic liquids / Ramesh L. Gardas in Industrial & engineering chemistry research, Vol. 47 n°15 (Août 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°15 (Août 2008) . - p. 5751–5757 Titre : A group contribution method for heat capacity estimation of ionic liquids Type de document : texte imprimé Auteurs : Ramesh L. Gardas, Auteur ; João A.P. Coutinho, Auteur Année de publication : 2008 Article en page(s) : p. 5751–5757 Note générale : Bibliogr. p. 5756-5757 Langues : Anglais (eng) Mots-clés : Ionic  liquids;  Liquid  heat  capacity;  Correlation Résumé : Based on experimental liquid heat capacity (CpL) data collected from the literature, a second-order group additivity method has been developed for the estimation of the liquid heat capacity of imidazolium-, pyridinium-, and pyrrolidinium-based ionic liquids (ILs) containing hexafluorophosphate (PF6), tetrafluoroborate (BF4), bis(trifluoromethanesulfonyl) amide (Tf2N), bromide (Br), ethyl sulfate (EtSO4), or trifluoromethane sulfonate (CF3SO3) as anions, covering wide ranges of temperature (196.36−663.10 K) and liquid heat capacity (264.8−825.0 J mol−1 K−1). It is shown that a good description of the literature data is obtained with the proposed method. For ca. 2400 data points from 19 ILs that have been studied, a mean percent deviation (MPD) of 0.36% with a maximum deviation of <2.5% was observed. From the total data points of estimated heat capacities, 90.2% present deviations of <1% from the experimental values, whereas only 0.9% have deviations of >2%. A correlation of heat capacities with molar volumes of the ILs was also developed for the estimation of heat capacity at 298.15 K. Therefore, the group contribution method developed here can be used to evaluate the liquid heat capacity of new ILs and, as data for new groups of cations and anions become available, can be extended to a larger range of ionic liquids. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800330v [article] A group contribution method for heat capacity estimation of ionic liquids [texte imprimé] / Ramesh L. Gardas, Auteur ; João A.P. Coutinho, Auteur . - 2008 . - p. 5751–5757. Bibliogr. p. 5756-5757 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°15 (Août 2008) . - p. 5751–5757 Mots-clés : Ionic  liquids;  Liquid  heat  capacity;  Correlation Résumé : Based on experimental liquid heat capacity (CpL) data collected from the literature, a second-order group additivity method has been developed for the estimation of the liquid heat capacity of imidazolium-, pyridinium-, and pyrrolidinium-based ionic liquids (ILs) containing hexafluorophosphate (PF6), tetrafluoroborate (BF4), bis(trifluoromethanesulfonyl) amide (Tf2N), bromide (Br), ethyl sulfate (EtSO4), or trifluoromethane sulfonate (CF3SO3) as anions, covering wide ranges of temperature (196.36−663.10 K) and liquid heat capacity (264.8−825.0 J mol−1 K−1). It is shown that a good description of the literature data is obtained with the proposed method. For ca. 2400 data points from 19 ILs that have been studied, a mean percent deviation (MPD) of 0.36% with a maximum deviation of <2.5% was observed. From the total data points of estimated heat capacities, 90.2% present deviations of <1% from the experimental values, whereas only 0.9% have deviations of >2%. A correlation of heat capacities with molar volumes of the ILs was also developed for the estimation of heat capacity at 298.15 K. Therefore, the group contribution method developed here can be used to evaluate the liquid heat capacity of new ILs and, as data for new groups of cations and anions become available, can be extended to a larger range of ionic liquids. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800330v

Modeling of biodiesel multicomponent systems with the cubic-plus-association (CPA) equation of state / Mariana B. Oliveira in Industrial & engineering chemistry research, Vol. 49 N° 3 (Fevrier 2010)

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 3 (Fevrier 2010) . - pp. 1419–1427 Titre : Modeling of biodiesel multicomponent systems with the cubic-plus-association (CPA) equation of state Type de document : texte imprimé Auteurs : Mariana B. Oliveira, Auteur ; António J. Queimada, Auteur ; João A.P. Coutinho, Auteur Année de publication : 2010 Article en page(s) : pp. 1419–1427 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Modeling--Biodiesel--Multicomponent--Systems--Cubic-Plus-Association--(CPA)  Equation--State Résumé : To supply biodiesel with the quality levels required by the standards for alternative fuels, the separation and purification units are extremely important in the biodiesel production plants. The correct knowledge and description of the phase equilibria in systems composed by transesterification products is essential for a correct operation and optimization of the purification process. For that purpose, the cubic-plus-association equation of state (CPA EoS) was here applied to model the phase equilibria of multicomponent systems common to biodiesel production and purification processes. It is shown that the CPA EoS can provide a good description of the liquid−liquid equilibria of multicomponent mixtures containing alcohols, glycerol, and fatty acid esters in the temperature range of operation of the separation units in biodiesel plants. As the liquid−liquid phase equilibrium description depends on the EoS parameters, a discussion is also presented about the best set of parameters and the method to estimate them. ISSN : 0888-5885 [article] Modeling of biodiesel multicomponent systems with the cubic-plus-association (CPA) equation of state [texte imprimé] / Mariana B. Oliveira, Auteur ; António J. Queimada, Auteur ; João A.P. Coutinho, Auteur . - 2010 . - pp. 1419–1427. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 3 (Fevrier 2010) . - pp. 1419–1427 Mots-clés : Modeling--Biodiesel--Multicomponent--Systems--Cubic-Plus-Association--(CPA)  Equation--State Résumé : To supply biodiesel with the quality levels required by the standards for alternative fuels, the separation and purification units are extremely important in the biodiesel production plants. The correct knowledge and description of the phase equilibria in systems composed by transesterification products is essential for a correct operation and optimization of the purification process. For that purpose, the cubic-plus-association equation of state (CPA EoS) was here applied to model the phase equilibria of multicomponent systems common to biodiesel production and purification processes. It is shown that the CPA EoS can provide a good description of the liquid−liquid equilibria of multicomponent mixtures containing alcohols, glycerol, and fatty acid esters in the temperature range of operation of the separation units in biodiesel plants. As the liquid−liquid phase equilibrium description depends on the EoS parameters, a discussion is also presented about the best set of parameters and the method to estimate them. ISSN : 0888-5885

Thermodynamic modeling of the aqueous solubility of PAHs / Mariana B. Oliveira in Industrial & engineering chemistry research, Vol. 48 N° 11 (Juin 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 11 (Juin 2009) . - pp. 5530–5536 Titre : Thermodynamic modeling of the aqueous solubility of PAHs Type de document : texte imprimé Auteurs : Mariana B. Oliveira, Auteur ; Vera L. Oliveira, Auteur ; João A.P. Coutinho, Auteur Année de publication : 2009 Article en page(s) : pp. 5530–5536 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Polycyclic  aromatic  hydrocarbons  Aqueous  solubilities  CPA  EoS Résumé : Polycyclic aromatic hydrocarbons (PAHs) are a family of compounds characterized by having two or more condensed aromatic rings. They are important environmental contaminants associated with oil spills and the incomplete combustion of organic materials. Different models are available in the literature for estimating the aqueous solubilities of organic compounds, but the most accurate are frequently based on the correlation of experimental data, which hampers their use as predictive tools. In this work, the cubic-plus-association equation of state (CPA EoS) is shown to be an accurate model for describing the aqueous solubilities of several solid PAHs in wide temperature and pressure ranges. The results obtained are in very close agreement with the literature data, even when the model is used in a totally predictive scheme. Following previous results on the aqueous solubilities of other organic pollutants, the use of the CPA EoS for describing the aqueous solubilities of organic pollutants such as polycyclic aromatic hydrocarbons is suggested. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900011g [article] Thermodynamic modeling of the aqueous solubility of PAHs [texte imprimé] / Mariana B. Oliveira, Auteur ; Vera L. Oliveira, Auteur ; João A.P. Coutinho, Auteur . - 2009 . - pp. 5530–5536. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 11 (Juin 2009) . - pp. 5530–5536 Mots-clés : Polycyclic  aromatic  hydrocarbons  Aqueous  solubilities  CPA  EoS Résumé : Polycyclic aromatic hydrocarbons (PAHs) are a family of compounds characterized by having two or more condensed aromatic rings. They are important environmental contaminants associated with oil spills and the incomplete combustion of organic materials. Different models are available in the literature for estimating the aqueous solubilities of organic compounds, but the most accurate are frequently based on the correlation of experimental data, which hampers their use as predictive tools. In this work, the cubic-plus-association equation of state (CPA EoS) is shown to be an accurate model for describing the aqueous solubilities of several solid PAHs in wide temperature and pressure ranges. The results obtained are in very close agreement with the literature data, even when the model is used in a totally predictive scheme. Following previous results on the aqueous solubilities of other organic pollutants, the use of the CPA EoS for describing the aqueous solubilities of organic pollutants such as polycyclic aromatic hydrocarbons is suggested. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900011g