New density and vapor–liquid equilibrium data of PCl₃-benzene binary system at atmospheric pressure (99.7–101.3 kPa) were carefully measured to provide crucial information for their industrial reaction and separation. The experimental mixture densities show excellent linear dependence on both solution composition and temperature and a generalized empirical correlation is proposed with an average relative deviation of 0.13%. The specific attractive P-π interaction between the phosphorus atom of PCl₃ and the π cloud of benzene seems to be quite strong in solution, leading to large negative excess volumes. But the π-π antibonding effect from benzene dimers are predominant in PCl₃ highly dilute solution, where positive excess volume and excess partial molar volumes of PCl₃ were observed. Experimental bubble points of the binary mixture were corrected to those under 101.325 kPa. Two distinctive methods of coexistence equation and activity coefficient models of Wilson and NRTL equations were applied to model the VLE data, and they yielded very consistent results. Although no azeotrope were found, this mixture exhibited quite low relative volatility.

仔细测量常压 (99.7–101.3 kPa)下 PCl ₃ -苯二元体系的新密度和汽液平衡数据，为其工业反应和分离提供关键信息。实验混合物密度显示出对溶液成分和温度的极好线性相关性，并且提出了平均相对偏差为 0.13% 的广义经验相关性。PCl ₃的磷原子和苯的 π 云之间的特殊吸引 P-π 相互作用在溶液中似乎非常强，导致大的负过量体积。但苯二聚体的 π-π 反键效应在 PCl ₃中占主导地位高度稀释的溶液，其中观察到PCl _{3 的}正过量体积和过量部分摩尔体积。二元混合物的实验泡点被校正为低于 101.325 kPa 的那些。威尔逊方程和 NRTL 方程的共存方程和活度系数模型的两种不同方法被应用于对 VLE 数据进行建模，它们产生了非常一致的结果。虽然没有发现共沸物，但这种混合物表现出相当低的相对挥发性。