Analysis of the membrane thickness effect on the pervaporation separation of methanol/methyl tertiary butyl ether mixtures

The effect of the membrane thickness on the pervaporation separation of methanol and methyl tertiary butyl ether mixtures through membranes was studied. Membranes of a wide range of thicknesses were prepared from two different polymers: cellulose acetate and poly(2,6-dimethyl-1,4-phenylene oxide). For each membrane, the experiments were performed at the same feed pressure, feed temperature and permeate pressure. The results showed that the permeate flux through both membrane types decreased markedly with increasing the membrane thickness, while the separation factor remained nearly constant. This behavior was discussed in terms of a resistance-in-series model.