Pervaporation characteristics of a benzoylchitosan membrane for benzene-cyclohexane mixtures

A benzoylchitosan was synthesized as a membrane material for separation of benzene/cyclohexane mixtures. When the benzoylchitosan membrane was applied to the permeation and separation of benzene/cyclohexane mixtures in pervaporation, both the permeation rate and benzene concentration in the permeate increased with increasing benzene concentration in the feed, and thus this membrane showed benzene permselectivity. Characteristics of permeation and separation of benzene/cyclohexane mixtures through the benzoylchitosan membrane were analyzed by the solution-diffusion model. It was found that the benzene permselectivity was dependent on both the sorption selectivity and diffusion selectivity but was significantly governed by the latter. Also a tentative model for the benzene permselectivity is discussed.