Estimation of Isobaric Vapour-Liquid Equilibria of THF/Acetic acid System using UNIFAC Method

Abstract

It is highly recommended that the solvents which are used to recover useful chemical compounds should be less harmful to health, safety and environment. The use of green solvents, particularly the solvents which are produced from renewable resources, is preferable. Furfural is produced from renewable raw material such as agricultural waste. Tetrahydrofuran (THF) which can be produced from furfural can potentially be used as a solvent to recover acetic acid. A separation system is required for the recovery of the solvent for reuse. The separation system design requires vapour-liquid equilibrium (VLE) data of the THF/Acetic acid binary system. The isobaric VLE data for THF/Acetic acid system are not available in the literature. The prediction of VLE data using group contribution methods can be preferred over experimental methods due to certain advantages for the preliminary design of the separation system. In this work, the binary VLE data for THF/Acetic acid system were estimated using the UNIFAC method. The thermodynamic consistency of the estimated data was checked by Herington’s area test and point-to-point test of VanNess. The data reduction was carried out by Wilson, NRTL and UNIQUAC models. The deviation between calculated and predicted values in vapour phase composition and temperature has been reported.