To provide an accurate prediction of the product component dependence of temperature and pressure in vacuum distillation and give convenient and efficient guidance for the designing of the process parameters of indust...To provide an accurate prediction of the product component dependence of temperature and pressure in vacuum distillation and give convenient and efficient guidance for the designing of the process parameters of industrial production, according to the molecular interaction volume model(MIVM), the separation coefficient(β) and vapor-liquid equilibrium composition of Au-Ag alloy at different temperatures are calculated. Combined with the vapor-liquid equilibrium(VLE) theory, the VLE phase diagrams, including the temperature-composition(T-x) and pressure-composition(p-x) diagrams of Au-Ag alloy in vacuum distillation are plotted. The triple points and condensation temperatures of gold and silver vapors are calculated as well. The results show that the β decreases and the contents of gold in vapor phase increase with the distillation temperature increasing. Low pressures have positive effect on the separation of Ag and Au. The difference between the condensation temperatures of gold and silver is about 450 K in the pressure range of 1-10 Pa.展开更多
Based on the free volume theory, lattice model, the Scatchard–Hildebrand theory, novel expressions of configuration partition function and excessive Gibbs free energy and component activity coefficients of solid solu...Based on the free volume theory, lattice model, the Scatchard–Hildebrand theory, novel expressions of configuration partition function and excessive Gibbs free energy and component activity coefficients of solid solutions were developed using configuration partition function and statistical thermodynamics of molecular interaction volume model (MIVM). Herein, the separation of the volume and energy parameters was achieved. The proposed model can reflect the contributions from both the molecular configuration micro-state number (entropy) and molecular interactions (enthalpy) toward excessive Gibbs free energy. The proposed equations are more consistent with the practical solid solutions. This model can use either the relevant binary infinite dilution activity coefficients or binary activity to describe and predict the thermodynamic properties of the multi-component solid solutions. Applications of the proposed model in some typical binary and ternary solid solution alloys revealed that the thermodynamic properties predicted by the proposed model were consistent with the experimental data and the proposed model was found to be superior to MIVM in terms of the prediction performance. Hence, it can be concluded that the proposed model exhibits good physical basis, applicability, stability and reliability.展开更多
The activity of components of Sn-Zn binary alloy system was predicted based on the molecular interaction volume model (MIVM). The calculated values are in good agreement with available experimental data of activitie...The activity of components of Sn-Zn binary alloy system was predicted based on the molecular interaction volume model (MIVM). The calculated values are in good agreement with available experimental data of activities, which indicates that this model is of stability and reliability because the MIVM has a good physical basis. The vapor-liquid phase equilibrium of Sn-Zn alloy system in vacuum distillation was calculated as a function of the activity coefficient. The results show that the content of Sn in vapor phase is 4.2x 10-7 (mass fraction) while in liquid phase it is 90% (mass fraction) at 1 073 K, and the content of Sn in vapor phase increases with increasing the melt temperature and content of Sn in liquid phase. Vacuum distillation experiments were carried out on Sn-Zn alloy for the proper interpretation of the results of the MIVM in the temperature range of 973-1 273 K under pressures of 15-200 Pa. The experimental results show that the content of Sn in vapor phase is 5x 10 6 (mass fraction) while in liquid phase it is 90% (mass fraction) under the operational condition of 1 073 K, 100 rain and 15 Pa. The experimental results are in good agreement with the predicted values of the MIVM for Zn-Sn binary alloy system.展开更多
基金supported by the National Natural Science Foundation of China (No.52064029)Yunling Scholarship of Yunnan Province Ten-Thousand Plan,China (No.KKRC201952012)Yunnan Province Ten Thousand Talents Program-Youth Top Talent Project,China (No.2018-73)。
文摘To provide an accurate prediction of the product component dependence of temperature and pressure in vacuum distillation and give convenient and efficient guidance for the designing of the process parameters of industrial production, according to the molecular interaction volume model(MIVM), the separation coefficient(β) and vapor-liquid equilibrium composition of Au-Ag alloy at different temperatures are calculated. Combined with the vapor-liquid equilibrium(VLE) theory, the VLE phase diagrams, including the temperature-composition(T-x) and pressure-composition(p-x) diagrams of Au-Ag alloy in vacuum distillation are plotted. The triple points and condensation temperatures of gold and silver vapors are calculated as well. The results show that the β decreases and the contents of gold in vapor phase increase with the distillation temperature increasing. Low pressures have positive effect on the separation of Ag and Au. The difference between the condensation temperatures of gold and silver is about 450 K in the pressure range of 1-10 Pa.
基金This work was financially supported by Yunnan Provincial Department of Education Science Research Fund Project(Grant Nos.2018JS551,2019J0025 and 2019J0891)Scientific Research Foundation of Kunming Metallurgy College(Grant No.Xxrcxm201802).
文摘Based on the free volume theory, lattice model, the Scatchard–Hildebrand theory, novel expressions of configuration partition function and excessive Gibbs free energy and component activity coefficients of solid solutions were developed using configuration partition function and statistical thermodynamics of molecular interaction volume model (MIVM). Herein, the separation of the volume and energy parameters was achieved. The proposed model can reflect the contributions from both the molecular configuration micro-state number (entropy) and molecular interactions (enthalpy) toward excessive Gibbs free energy. The proposed equations are more consistent with the practical solid solutions. This model can use either the relevant binary infinite dilution activity coefficients or binary activity to describe and predict the thermodynamic properties of the multi-component solid solutions. Applications of the proposed model in some typical binary and ternary solid solution alloys revealed that the thermodynamic properties predicted by the proposed model were consistent with the experimental data and the proposed model was found to be superior to MIVM in terms of the prediction performance. Hence, it can be concluded that the proposed model exhibits good physical basis, applicability, stability and reliability.
基金Project(2012CB722803) supported by the Key Project of National Basic Research and Development Program of ChinaProject(2011FA008)supported by the Key Project of Science and Technology Program of Yunnan Province,China
文摘The activity of components of Sn-Zn binary alloy system was predicted based on the molecular interaction volume model (MIVM). The calculated values are in good agreement with available experimental data of activities, which indicates that this model is of stability and reliability because the MIVM has a good physical basis. The vapor-liquid phase equilibrium of Sn-Zn alloy system in vacuum distillation was calculated as a function of the activity coefficient. The results show that the content of Sn in vapor phase is 4.2x 10-7 (mass fraction) while in liquid phase it is 90% (mass fraction) at 1 073 K, and the content of Sn in vapor phase increases with increasing the melt temperature and content of Sn in liquid phase. Vacuum distillation experiments were carried out on Sn-Zn alloy for the proper interpretation of the results of the MIVM in the temperature range of 973-1 273 K under pressures of 15-200 Pa. The experimental results show that the content of Sn in vapor phase is 5x 10 6 (mass fraction) while in liquid phase it is 90% (mass fraction) under the operational condition of 1 073 K, 100 rain and 15 Pa. The experimental results are in good agreement with the predicted values of the MIVM for Zn-Sn binary alloy system.