The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform
Mahmood Moshfeghian - One of the best experts on this subject based on the ideXlab platform.
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Development and extension of PSRK/UNIQUAC model to methane and nitrogen gases
Fluid Phase Equilibria, 1998Co-Authors: Ahmad Keshtkar, F. Jalali, Mahmood MoshfeghianAbstract:Abstract Two successful procedures for matching the equation of state (EOS) and the excess Gibbs energy model at zero pressure belong to Michelsen [M.L. Michelsen, Fluid Phase Equilibria, 60 (1990) 213] and Holderbaum-Gmehling [T. Holderbaum, J. Gmehling, Fluid Phase Equilibria, 70 (1991) 251]. These procedures lead to volume independent mixing rules for the mixture parameter a. Michelsen proposed the MHV1 and MHV2 mixing rules and Holderbaum-Gmehling proposed the PSRK mixing rule. Keshtkar et al. [A. Keshtkar, F. Jalali, M. Moshfegian, Fluid Phase Equilibria, 140 (1997) 107] demonstrated the utility of these mixing rules together with UNIFAC and UNIQUAC models for the prediction of high-pressure vapor-liquid equilibrium (VLE) of CO2-binary systems. Also, they showed that the PSRK/UNIQUAC model gives better VLE results than other models. In this paper, we develop and extend the above model to methane and nitrogen gases. For this purpose, it is required that the missing interaction parameters of model are fitted with experimental VLE data. The VLE calculations show that good agreement between calculated results and experimental data can be produced by using the obtained parameters.
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Evaluation of vapor—liquid equilibrium of CO2 binary systems using UNIQUAC-based Huron—Vidal mixing rules
Fluid Phase Equilibria, 1997Co-Authors: Ahmad Keshtkar, F. Jalali, Mahmood MoshfeghianAbstract:Abstract Since Huron and Vidal [M.J. Huron, J. Vidal, Fluid Phase Equilib. 3 (1979) 255] developed the basic idea of the so-called GE mixing rules, similar models have been proposed by different authors. In most of them, a group-contribution method like the UNIFAC model is used with the equation of state to enable the description of vapor-liquid equilibrium (VLE) at high temperatures and pressures including supercritical compounds. In this work we intended to use the UNIQUAC instead of the UNIFAC method as GE model in SRK equation of state. For comparison between Huron-Vidal-type mixing rules, we selected the modified Huron-Vidal first-order (MHV1) and second-order (MHV2) mixing rules proposed by Michelsen [M.L. Michelsen, Fluid Phase Equilib. 60 (1990a) 213; M.L. Michelsen, Fluid Phase Equilib. 60 (1990b) 42.] and PSRK mixing rule proposed by Holderbaum and Gmehling [T. Holderbaum, J. Gmehling, Fluid Phase Equilib. 70 (1991) 251.]. In other words, this paper investigates the ability of several mixing rules to predict and correlate the high-pressure vapor-liquid equilibrium used in combination with the UNIFAC and UNIQUAC models. For comparison of these mixing rules, the carbon dioxide binary mixtures have been chosen because carbon dioxide has numerous applications in supercritical fluid processes. The missing interaction parameters of UNIFAC and UNIQUAC were estimated through the regression of experimental vapor-liquid equilibrium data. For comparison of UNIQUAC-based mixing rules with each other, the interaction parameters of 51 carbon dioxide binary systems have been determined. Furthermore, a comparison between UNIFAC- and UNIQUAC-based SRK equation of state is presented. The results show that all of the UNIFAC- and UNIQUAC-based mixing rules, with parameters derived from VLE, can be used for reliable calculations of phase equilibrium. It is shown that the PSRK/UNIQUAC mixing rule can correlate the data for the best VLE results. Also, it is shown that the use of the second-order mixing rule in UNIQUAC-based SRK equation of state does not necessarily improve the results of VLE calculations.
Ahmad Keshtkar - One of the best experts on this subject based on the ideXlab platform.
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Development and extension of PSRK/UNIQUAC model to methane and nitrogen gases
Fluid Phase Equilibria, 1998Co-Authors: Ahmad Keshtkar, F. Jalali, Mahmood MoshfeghianAbstract:Abstract Two successful procedures for matching the equation of state (EOS) and the excess Gibbs energy model at zero pressure belong to Michelsen [M.L. Michelsen, Fluid Phase Equilibria, 60 (1990) 213] and Holderbaum-Gmehling [T. Holderbaum, J. Gmehling, Fluid Phase Equilibria, 70 (1991) 251]. These procedures lead to volume independent mixing rules for the mixture parameter a. Michelsen proposed the MHV1 and MHV2 mixing rules and Holderbaum-Gmehling proposed the PSRK mixing rule. Keshtkar et al. [A. Keshtkar, F. Jalali, M. Moshfegian, Fluid Phase Equilibria, 140 (1997) 107] demonstrated the utility of these mixing rules together with UNIFAC and UNIQUAC models for the prediction of high-pressure vapor-liquid equilibrium (VLE) of CO2-binary systems. Also, they showed that the PSRK/UNIQUAC model gives better VLE results than other models. In this paper, we develop and extend the above model to methane and nitrogen gases. For this purpose, it is required that the missing interaction parameters of model are fitted with experimental VLE data. The VLE calculations show that good agreement between calculated results and experimental data can be produced by using the obtained parameters.
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Evaluation of vapor—liquid equilibrium of CO2 binary systems using UNIQUAC-based Huron—Vidal mixing rules
Fluid Phase Equilibria, 1997Co-Authors: Ahmad Keshtkar, F. Jalali, Mahmood MoshfeghianAbstract:Abstract Since Huron and Vidal [M.J. Huron, J. Vidal, Fluid Phase Equilib. 3 (1979) 255] developed the basic idea of the so-called GE mixing rules, similar models have been proposed by different authors. In most of them, a group-contribution method like the UNIFAC model is used with the equation of state to enable the description of vapor-liquid equilibrium (VLE) at high temperatures and pressures including supercritical compounds. In this work we intended to use the UNIQUAC instead of the UNIFAC method as GE model in SRK equation of state. For comparison between Huron-Vidal-type mixing rules, we selected the modified Huron-Vidal first-order (MHV1) and second-order (MHV2) mixing rules proposed by Michelsen [M.L. Michelsen, Fluid Phase Equilib. 60 (1990a) 213; M.L. Michelsen, Fluid Phase Equilib. 60 (1990b) 42.] and PSRK mixing rule proposed by Holderbaum and Gmehling [T. Holderbaum, J. Gmehling, Fluid Phase Equilib. 70 (1991) 251.]. In other words, this paper investigates the ability of several mixing rules to predict and correlate the high-pressure vapor-liquid equilibrium used in combination with the UNIFAC and UNIQUAC models. For comparison of these mixing rules, the carbon dioxide binary mixtures have been chosen because carbon dioxide has numerous applications in supercritical fluid processes. The missing interaction parameters of UNIFAC and UNIQUAC were estimated through the regression of experimental vapor-liquid equilibrium data. For comparison of UNIQUAC-based mixing rules with each other, the interaction parameters of 51 carbon dioxide binary systems have been determined. Furthermore, a comparison between UNIFAC- and UNIQUAC-based SRK equation of state is presented. The results show that all of the UNIFAC- and UNIQUAC-based mixing rules, with parameters derived from VLE, can be used for reliable calculations of phase equilibrium. It is shown that the PSRK/UNIQUAC mixing rule can correlate the data for the best VLE results. Also, it is shown that the use of the second-order mixing rule in UNIQUAC-based SRK equation of state does not necessarily improve the results of VLE calculations.
Dimitrios P. Tassios - One of the best experts on this subject based on the ideXlab platform.
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Prediction of vapor-liquid equilibrium with the LCVM model : a linear combination of the Vidal and Michelsen mixing rules coupled with the original UNIFAC and the t-mPR equation of state
Fluid Phase Equilibria, 1994Co-Authors: Christos Boukouvalas, Nikolaos Spiliotis, Philippos Coutsikos, Nikolaos Tzouvaras, Dimitrios P. TassiosAbstract:Abstract Boukouvalas, C., Spiliotis, N., Coutsikos, P., Tzouvaras, N. and Tassios, D., 1994. Prediction of vapor-liquid equilibrium with the LCVM model: a linear combination of the Vidal and Michelsen mixing rules coupled with the original UNIFAC and the t-mPR equation of state. Fluid Phase Equilibria, 92: 75-106. A new mixing rule, a linear combination of the Vidal and Michelsen rules, for the attractive term parameter in cubic equations of state (EoS) has been developed. This mixing rule, coupled with a translated and modified Peng-Robinson EoS and the original UNIFAC, leads to the LCVM model which provides successful prediction of vapor-liquid equilibria (VLE) of nonpolar and polar systems at low and high pressures. This also applies to systems of dissimilar component size, such as those containing gases (C2H6, CO2 and CH4) with large n-alkanes, where other EoS/GE predictive models, such as MHV2 and PSRK, perform poorly.
Ulrich Hamm - One of the best experts on this subject based on the ideXlab platform.
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Veröffentlichungen von Prof. Dr. Ulrich Hamm und Mitarbeitern/-innen [Publications of Prof. Dr. Ulrich Hamm and staff]
2006Co-Authors: Ulrich HammAbstract:Veroffentlichungen von: U. Hamm S. Wild L. Besschaposchnikowa A. Dahlke F. Gronefeld D. Halpin K. Kohlhoff J. Michelsen M. Muller J. Niessen A. Radlinsky T. Richter M. Rippin J. Sanders M. Schermer O. Schmid
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Veröffentlichungen von Prof. Dr. Ulrich Hamm und Mitarbeitern/-innen
2004Co-Authors: Ulrich HammAbstract:Veroffentlichungen von: U. Hamm L. Besschaposchnikowa A. Dahlke F. Gronefeld D. Halpin K. Kohlhoff J. Michelsen M. Muller J. Niessen A. Radlinsky T. Richter M. Rippin J. Sanders M. Schermer O. Schmid
F. Jalali - One of the best experts on this subject based on the ideXlab platform.
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Development and extension of PSRK/UNIQUAC model to methane and nitrogen gases
Fluid Phase Equilibria, 1998Co-Authors: Ahmad Keshtkar, F. Jalali, Mahmood MoshfeghianAbstract:Abstract Two successful procedures for matching the equation of state (EOS) and the excess Gibbs energy model at zero pressure belong to Michelsen [M.L. Michelsen, Fluid Phase Equilibria, 60 (1990) 213] and Holderbaum-Gmehling [T. Holderbaum, J. Gmehling, Fluid Phase Equilibria, 70 (1991) 251]. These procedures lead to volume independent mixing rules for the mixture parameter a. Michelsen proposed the MHV1 and MHV2 mixing rules and Holderbaum-Gmehling proposed the PSRK mixing rule. Keshtkar et al. [A. Keshtkar, F. Jalali, M. Moshfegian, Fluid Phase Equilibria, 140 (1997) 107] demonstrated the utility of these mixing rules together with UNIFAC and UNIQUAC models for the prediction of high-pressure vapor-liquid equilibrium (VLE) of CO2-binary systems. Also, they showed that the PSRK/UNIQUAC model gives better VLE results than other models. In this paper, we develop and extend the above model to methane and nitrogen gases. For this purpose, it is required that the missing interaction parameters of model are fitted with experimental VLE data. The VLE calculations show that good agreement between calculated results and experimental data can be produced by using the obtained parameters.
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Evaluation of vapor—liquid equilibrium of CO2 binary systems using UNIQUAC-based Huron—Vidal mixing rules
Fluid Phase Equilibria, 1997Co-Authors: Ahmad Keshtkar, F. Jalali, Mahmood MoshfeghianAbstract:Abstract Since Huron and Vidal [M.J. Huron, J. Vidal, Fluid Phase Equilib. 3 (1979) 255] developed the basic idea of the so-called GE mixing rules, similar models have been proposed by different authors. In most of them, a group-contribution method like the UNIFAC model is used with the equation of state to enable the description of vapor-liquid equilibrium (VLE) at high temperatures and pressures including supercritical compounds. In this work we intended to use the UNIQUAC instead of the UNIFAC method as GE model in SRK equation of state. For comparison between Huron-Vidal-type mixing rules, we selected the modified Huron-Vidal first-order (MHV1) and second-order (MHV2) mixing rules proposed by Michelsen [M.L. Michelsen, Fluid Phase Equilib. 60 (1990a) 213; M.L. Michelsen, Fluid Phase Equilib. 60 (1990b) 42.] and PSRK mixing rule proposed by Holderbaum and Gmehling [T. Holderbaum, J. Gmehling, Fluid Phase Equilib. 70 (1991) 251.]. In other words, this paper investigates the ability of several mixing rules to predict and correlate the high-pressure vapor-liquid equilibrium used in combination with the UNIFAC and UNIQUAC models. For comparison of these mixing rules, the carbon dioxide binary mixtures have been chosen because carbon dioxide has numerous applications in supercritical fluid processes. The missing interaction parameters of UNIFAC and UNIQUAC were estimated through the regression of experimental vapor-liquid equilibrium data. For comparison of UNIQUAC-based mixing rules with each other, the interaction parameters of 51 carbon dioxide binary systems have been determined. Furthermore, a comparison between UNIFAC- and UNIQUAC-based SRK equation of state is presented. The results show that all of the UNIFAC- and UNIQUAC-based mixing rules, with parameters derived from VLE, can be used for reliable calculations of phase equilibrium. It is shown that the PSRK/UNIQUAC mixing rule can correlate the data for the best VLE results. Also, it is shown that the use of the second-order mixing rule in UNIQUAC-based SRK equation of state does not necessarily improve the results of VLE calculations.