Vapor-liquid equilibrium for formic acid-triethylamine system examined by the use of a modified still. Formic acid-trialkylamine azeotropes.

Abstract

In order to shed light on the previous confused data reported for the constant-boiling liquids for the formic acid-trialkylamine system, vapor-liquid equilibria for a representative formic acid-triethylamine system under a number of pressures were examined by the use of a modified still designed for this purpose. The diagrams obtained and the pressure dependence of the azeotropic compositions clearly indicate azeotropic features. Precise composition of the maximum azeotrope was determined for this system as well as for other formic acid-trialkylamine systems.