Pervaporation of Toluene/Alcohol Mixtures through a Coextruded Linear Low-Density Polyethylene Membrane

Abstract

The pervaporation characteristics of toluene/methanol, toluene/ethanol, and toluene/propanol mixtures through a linear low-density polyethylene membrane were investigated at different feed compositions. These characteristics were obtained from quantities such as the swelling ratio, permeation rate, and selectivity. In all cases toluene permeates preferentially through the membrane, with a separation factor up to 66 and fluxes varying between 0.1 and 1.4 kg/m2·h. Predictions based on the Flory−Huggins theory have shown that toluene is preferentially sorbed by the membrane. The pervaporation flux increases and the selectivity decreases with the toluene content in the feed. The experimental results show that pure-alcohol fluxes decrease with the molecular size.