Solvent Selection for Cyclohexane−Cyclohexene−Benzene Separation by Extractive Distillation Using Non-Steady-State Gas Chromatography

Abstract

The infinite-dilution activity coefficients of cyclohexane, cyclohexene, and benzene in N,N-dimethylformamide, N-methylpyrrolidone, N,N-dimethylacetamide, phenyl acetate, and dimethyl malonate have been determined at temperatures ranging from 40 to 80 °C, by non-steady-state gas chromatography. From these data, the limiting selectivity−solvency properties for cyclohexane−benzene, cyclohexene−benzene, and cyclohexane−cyclohexene, in the presence of the aforementioned solvents, are studied, and the solvents tested are considered for the cyclohexane−cyclohexene−benzene separation by extractive distillation. According to the results, N,N-dimethylacetamide seems to be an adequate solvent for the cyclohexane−benzene and cyclohexene−benzene separations. The separation of cyclohexane−cyclohexene is the most difficult, in spite of the difference of boiling points, much higher than for cyclohexane−benzene.

Extractive Distillation: A Review

“…It involves measuring the retention behavior of a solute in an inert carrier gas stream passing through a column containing a solvent-coated solid support (Donohue et al, 1985;Thomas et al, 1982;Vega et al, 1997).…”

Selective adsorptive separation of cyclohexane over benzene using thienothiophene cages

“…6,7 The most common industrial methods for the separation of Bz/Cy mixtures are extractive and azeotropic distillations. [8][9][10] Nonetheless, these processes require complex operation and high energy, leading to high operating costs. Exploiting molecular differences in terms of size and geometry, many efficient separation methods have been developed to separate Bz/Cy mixtures using membranes and porous materials.…”

Phase Behavior and Thermodynamic Model Parameters in Simulations of Extractive Distillation for Azeotrope Separation

“…Vega et al . 43 found that NMP is an efficient solvent for separating benzene-cyclohexane-cyclohexene mixtures using non-steady-state gas chromatography. However, a few studies 40 , 48 have shown that NMP is not an efficient solvent for separating mixtures that contain binary azeotropes of benzene-cyclohexane.…”