Abstract: Vapor-liquid equilibrium data of supercritical carbon dioxide+n-hexane system were measured at 313 K, 333 K, 353 K and 373 K in the pressure range of 2.15—12.63 MPa.The measurements were carried out in a cylindrical autoclave with a movable piston.It was shown that the density of the gas phase increased with increasing pressure at the given temperature, but the density of the liquid phase decreased.The high pressure data were calculated with the Franck equation.The results were in agreement with experimental data.Furthermore,the semi-empirical equation of Chrastil was used to correlate the solubility of n-hexane in supercritical carbon dioxide,and the parameters in the equation were obtained.

摘要： 利用可变体积高压釜，在313、333、353、373 K下，测定了2.15～12.63 MPa范围内高压CO₂与正己烷二元系统的气液两相平衡组成、密度、摩尔体积、气液相分配系数和正己烷在高压CO₂中的溶解度.实验结果表明：在相同温度下，平衡气相的密度随着压力的增大而增加，而液相的密度随压力的增大而减小到临界密度.用Franck方程进行了拟合，所得结果与实验数据相当符合.同时应用Chrastil半经验溶解度-密度方程拟合得出了正己烷在高压CO₂中的溶解度数据，得到对于该系统的溶解度方程参数.