| It has important implications to recycle the Sn-Sb alloys produced from the smelting process of Sn and Sb and their secondary resources due to the rapid reduction of non-ferrous metals resources and the complexity of minerals. Vacuum distillation has many advantages such as short flow sheet, zero pollution and high metal recovery rate in disposing of the Sn-Sb alloys. The prediction and experimental determination of activities of components of alloys and the vapor-liquid equilibrium (VLE) prediction model will be carried out by taking the Sn-Sb alloy as the research project. Meanwhile, the corresponding experiments of VLE will be carried out for validation purpose in this work. The main research contents and conclusions of this work are as following:1. Firstly, the molecular interaction volume model, viz., MIVM was simplified, the activities of Sn-Sb alloy at 905K were then predicted by using the simplified MIVM, Wilson equation and Miedema model, respectively. The average relaive deviations and average standard deviations of all above models have been calculated, which indicates that the average relaive deviations of them were ±0.09%, ±0.37% and ±11.98% along with the average standard deviations of ±0.0006, ±0.001 and ±12.08%, respectively. Secondly, the model parameters of the simplified MIVM were calculated in the temperature range of 1073K-1573K and the activities and activity coefficients of Sn-Sb alloy were predicted in the temperature range of 1073K-1573K by using the simplified MIVM.2. The activities of components of Sn-Sb alloy were determined by using the Electromotive force (EMF) method with LiCl+KCl+SnCl2 as liquid electrolyte at 905K. The obtained activities were compared with datas found in literature, which indicate a good fit. The activities found in the literature were consistent with the activities measured by using the Electromotive force (EMF) method with Yttria (8 mol%) Stabilized Zirconia (8YSZ) and the liquid electrolytes, which demonstrate the feasibility of measuring activities at high or low temperature in this work. Then, the activities and other thermodynamic datas of Sn-Sb alloy were measured by using the MEF method at the temperatue of 905K and 1073K.3. The verification and filter for the simplified MIVM, Wilson equation and Miedema model was carried out by using the experimental data of activities available in literatures and determined in this work. The minimum average relative deviation was ±5.68% for the simplified MIVM. The prediction accuracy of the simplified MIVM and Wilson equation are basically the same. The largest average relative deviation was ±12.47% for the Miedema model indicating that the prediction accuracy of Miedema was most poor among these three models. Moreover, the MIVM has a clear physical basis and less empirical parameters was needed in the prediction process. The above analysis indicates that the simplified MIVM was reliable for predicting the activities of components of Sn-Sb alloys.4. The method for calculation of separation coefficient and vapor-liquid phase equilibrium was amended and perfected by using the simplified MIVM. The vapor-liquid phase equilibrium of Sn-Sb binary alloys were then calculated by using this new method.A new VLE prediction model of Sn-Sb alloy was built up by using the simplified MIVM based on the VLE theory. Then, the VLE data were calculated by using this new model, and the VLE phase diagrams (including T-x(y) and p-x(y) phase diagram) of Sn-Sb binary alloys were then plotted by using the calculated VLE data.The VLE was experimentally determined for Sn-Sb binary alloys. The comparison between the calculated results and the experimental VLE data shows that the calculated results match with the experimental data.Above all, this work will enrich the thermodynamic data of binary alloys, improve and perfect the basic theory of vacuum distillation, and provide the reliable theoretical foundation for separation of non-ferrous metals alloys by vacuum distillation.
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