Associating fluids containing water and alkanols show a strong non-ideal behaviour on thermodynamic properties Simple cubic equations of state （EOS）. such as the Peng-Robinson （PR） equation, with conventional mixi...Associating fluids containing water and alkanols show a strong non-ideal behaviour on thermodynamic properties Simple cubic equations of state （EOS）. such as the Peng-Robinson （PR） equation, with conventional mixing rules are popular lbr its simplicity and eas3＇ implementation. However it is incapable of reliably representing the phase behaviour of associating mixtures. An effort has been made in this study to develop a new model in which the non-densit3＇-dependent mixing rules are applied to the PR EOS to represent the phase behaviour of associating fluids. The proposed model takes into account of the polarity in the attractive term of the EOS by including both the conventional random mixing term and the asymmetric interaction term. The proposed model has been successfully applied to the calculation of the vapor-liquid equilibrium （VLE） and liquid-liquid equilibrium （LLE） of fluids containing water, alkanols, acid gases, and hydrocarbons. A satisfactory agreement between the predictions of the proposed model and the experimental data in the literature is reached.展开更多
A novel alpha function for Peng-Robinson equation of state was proposed and generalized with acentric factor and dipole moment for predicting thermodynamic properties of non-polar,weakly polar,and polar compounds.The ...A novel alpha function for Peng-Robinson equation of state was proposed and generalized with acentric factor and dipole moment for predicting thermodynamic properties of non-polar,weakly polar,and polar compounds.The parameters of new alpha function were fitted with vapor pressures of 70 compounds.Six different methods were investigated for the correlation of parameters of new alpha function and Heyen alpha function.The generalized new alpha function passed the consistency test.The results indicated that the predictive accuracy of generalized new alpha function and generalized Heyen alpha function was improved for the estimation of vapor pressure of 11 kinds of compounds,with the average relative deviations(ARDs)being 2.60%and 2.76%.The ARDs of the two generalized alpha functions were 2.04%and 2.09%for the enthalpy of vaporization.However,the generalized new alpha function and the other alpha functions had great deviations for the prediction of liquid volumes and isobaric heat capacities.The alpha function that was generalized with acentric factor and reduced dipole moment was more accurate than that was generalized with acentric factor,especially for the prediction of vapor pressure and enthalpy of vaporization of polar compounds.展开更多
文摘Associating fluids containing water and alkanols show a strong non-ideal behaviour on thermodynamic properties Simple cubic equations of state （EOS）. such as the Peng-Robinson （PR） equation, with conventional mixing rules are popular lbr its simplicity and eas3＇ implementation. However it is incapable of reliably representing the phase behaviour of associating mixtures. An effort has been made in this study to develop a new model in which the non-densit3＇-dependent mixing rules are applied to the PR EOS to represent the phase behaviour of associating fluids. The proposed model takes into account of the polarity in the attractive term of the EOS by including both the conventional random mixing term and the asymmetric interaction term. The proposed model has been successfully applied to the calculation of the vapor-liquid equilibrium （VLE） and liquid-liquid equilibrium （LLE） of fluids containing water, alkanols, acid gases, and hydrocarbons. A satisfactory agreement between the predictions of the proposed model and the experimental data in the literature is reached.
基金supported by National Natural Science Foundation of China(22008129,22108138)。
文摘A novel alpha function for Peng-Robinson equation of state was proposed and generalized with acentric factor and dipole moment for predicting thermodynamic properties of non-polar,weakly polar,and polar compounds.The parameters of new alpha function were fitted with vapor pressures of 70 compounds.Six different methods were investigated for the correlation of parameters of new alpha function and Heyen alpha function.The generalized new alpha function passed the consistency test.The results indicated that the predictive accuracy of generalized new alpha function and generalized Heyen alpha function was improved for the estimation of vapor pressure of 11 kinds of compounds,with the average relative deviations(ARDs)being 2.60%and 2.76%.The ARDs of the two generalized alpha functions were 2.04%and 2.09%for the enthalpy of vaporization.However,the generalized new alpha function and the other alpha functions had great deviations for the prediction of liquid volumes and isobaric heat capacities.The alpha function that was generalized with acentric factor and reduced dipole moment was more accurate than that was generalized with acentric factor,especially for the prediction of vapor pressure and enthalpy of vaporization of polar compounds.
