甲基二氯硅烷+甲基三氯硅烷+二甲基二氯硅烷+苯多元系常压汽液平衡研究

卤代硅烷的相平衡数据为硅烷生产所需,而这方面的研究又较缺乏,尤其是甲基乙烯基二氯硅烷生产中所需的汽液相平衡数据尚未见报道.今用新型泵式沸点仪测定了常压(101.325 kPa)下甲基二氯硅烷 甲基三氯硅烷 二甲基二氯硅烷 苯四元系及其四个三元体系和六个二元体系在不同液相组成时的泡点.由所测的二元系数据,用过量自由焓Q函数间接法推算了与之平衡的汽相组成.再用最小二乘法求出二元体系的最佳配偶液相活度系数模型参数.所得的六组最佳二元系Wilson模型参数符合热力学一致性,并用于该体系三元和四元系汽液相平衡数据的预测,将计算的泡点与实验测得的泡点作了比较,其拟合精度良好,关联结果令人满意,硅烷二元系、多元系的热力学模型及VLE数据可为该体系的分离设计提供必要的理论依据.

Isobaric Vapor-Liquid Equilibrium for Methyldichlorosilane+Methyltrichlorosilane +Dimethyldichlorosilane+Benzene Systems

The data of vapor-liquid equilibrium (VLE) of the halogenated silane are necessary for the production of silane, especially for methylvinyldichlorosilane production, due to the lake of relevant reports referring to the VLE data needed. The bubble points of various liquid phase compositions for the quaternary system, methyldichlorosilane methyltrichlorosilane dimethyldichlorosilane benzene, and its ternary and binary systems were measured with a new pump-ebulliometer at the pressure of 101.325 kPa. According to the measured data of above binary systems, the binary compositions of the equilibrium vapor were calculated by the indirect method of the Q function of molar excess Gibbs energy, and then by using the least-squares fit, the parameters of the best activity coefficient model for the matched liquid phase were obtained. The obtained Wilson optimum model parameters of the binary systems agree well with the thermodynamic consistency, and they were used to predict the VLE data of the ternary and quaternary systems. Comparing the calculated bubble point of those systems with that of the experimental data, the fitting accuracies are good and the correlation results are satisfactory. The obtained VLE data of binary and multilateral systems provide a necessary theoretical basis for the production of silane.