关键词: solid-liquid equilibrium;terephthalic acid;λh model

Abstract: Terephthalic acid(PTA) is practically one of the main materials of polyester. Its
corresponding solid-liquid equilibrium data will provide essential support for industry
design and further theoretical studies. In this work,solid-liquid equilibriums of
terephthalic acid in four solvents, N,N-dimethylformamide, N,N-
dimethylacetamide,dimethylsulphoxide and N-methyl-2-ketopyrrolidene, were determined in the
temperature range from 293.15 K to364.6 K by dynamic method. All these data were regressed
by λh model, Wilson model and NRTL model, averageabsolute relative deviations of which are
1.25%, 15.02% and 7.22% respectively. It indicates that λh model is mostsuitable for
description of the solid-liquid equilibrium containing PTA.

Key words: solid-liquid equilibrium, terephthalic acid, λh model