平均吸引势模型状态方程用于固体在超临界流体中溶解度的计算

基于膨胀液体概念，把超临界流体看作是被气体膨胀了的液体，并假设体系的分子吸引势为范德华气体和凝聚液体吸引势的体积平均值、导出了一个平均吸引势模型状态方程。该方程较好地关联了纯溶剂蒸汽压及超临界二氧化碳的Ｐ－Ｖ－Ｔ关系；并关联了１４种固体溶质在超临界二氧化碳中的溶解度数据，结果优于ＲＫ、ＳＲＫ及ＰＲ方程。

An Equation of State Based on Average Attractive Potential Model for Calculating Solubilities of Solids in Supercritical Fluid

Based on the expanded liquid concept,the supercritical fluid is considered as a liquid expanded by gas.It is asaumed that the moleeular attractive potential of a system can be taken as the volumetric average for those of van der Waals gas and the condensed liquid,thus a new equation of state based on average attractive potential model has been proposed.The equation gives a good correlation for vapor pressures of pure solvents as well as P-V-T behaviors of supercritical carbon dioxide.The solubilities of 14 solid solutes in supercritical carbon dioxide have been correlated by the proposed equation of state.The results show that the proposed equation gives better correlation than that by the RK,SRK and PR equation.