The specific features of quaternary system phase diagram transformations induced by formation ofboundary tangential azeotrope were investigated. The characteristics of bifurcation states corresponding to the transition from one structure of the diagram to another were determined. The principal possible transformations of diagrams with varying pressure were illustrated by the systems acetone-chloroform-ethanol-water and chloroform-ethanol-cyclohexane-water. The obtained results expand the understanding of thermodynamics of heterogeneous equilibria of multicomponent systems and make it possible to solve the practical problem of maintaining favorable phase equilibrium conditions for rectification in certain pressure ranges.

中文翻译：

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通过边界切向共沸阶段的四元体系相图的拓扑变换

研究了由边界切向共沸物形成引起的四元体系相图转变的具体特征。确定了对应于从图的一种结构到另一种结构的转变的分岔状态的特征。丙酮-氯仿-乙醇-水和氯仿-乙醇-环己烷-水系统说明了不同压力下图的主要可能转换。所得结果扩展了对多组分体系非均相平衡热力学的理解，使解决在一定压力范围内保持精馏的有利相平衡条件的实际问题成为可能。