静态蒸汽总压法研究二氟二氯甲烷-乙醚、乙醚-丙酮二元系的恒温汽液平衡

ISOTHERMAL VAPOR-LIQUID EQUILIBRIA FOR DICHLORODIFLUOROMETHANE-DIETHYLETHER AND DIETHYLETHER-ACETONE BINARY SYSTEMS BY STATIC TOTAL-VAPOR-PRESSURE METHOD

新研制了带视镜的高压静态平衡器,可以观察平衡系统内相的分布情况及准确测定相体积,测压范围0～10MPa,实验在1/2全浓度范围内可连续进行.用此平衡器测定了二氟二氯甲烷、乙醚、丙酮在常沸点以上的蒸汽压以及二氟二氯甲烷-乙醚、乙醚-丙酮2对二元系的加压汽液平衡,获得了T、p、n_T、z以及V^g的数据.进一步用物料衡算与由T、p、x推算y的方法相结合,计算了平衡相组成x和y.汽相逸度系数用改进的PR状态方程计算.

A new static high pressure(0-10 MPa)equilibrium cell with viewing window was established. The volumes of both vapor and liquid phases can be accurately determined from the window. The degassed pure liquids can be fed continuously, therefore, one half of a phase diagram can be determined in a single run of experiment. Vapor pressures of pure dichloro-difluoromethane, diethyether and acetone above ordinary boiling point and isothermal vapor-liquid equilibria of two binary systems, dichlorodifluoromethane-diethylether and diethylether-acetone were measured. Temperature T, total amount nT and total composition z of the system, total vapor pressure p and volume of vapor phase Vg were taken directly from the experiment. With the use of material balance and the method of calculating vapor compositions y from T, p and x, equilibrium liquid and vapor composition x and y of these binaries were obtained. The fugacity coefficients needed during the calculations were estimated by the modified Peng-Robinson equation of state.