Pervaporation separation of aqueous organic mixtures through sulfated zirconia-poly(vinyl alcohol) membrane

Sulfated zirconia-poly(vinyl alcohol) membranes were prepared, and pervaporation performances for aqueous organic mixtures were investigated. These hydrophilic membranes were formed by crosslinking poly(vinyl alcohol) (PVA) with the solid acid of sulfated zirconia by an acid-catalyzed reaction. The pervaporation performances were measured as a function of the content ratio of sulfated zirconia to PVA, which affected the degree of swelling for water and the crosslinking density of the membrane. The membrane selectivity in pervaporation of aqueous organic mixtures increased in order of acetic acid < ethanol < 2-ethoxyethanol without sacrificing the permeation rate, depending on their feed compositions. The effects of feed temperature and concentration on the membrane performance were also significant. It was found that sulfated zirconia in the membrane preparation played an important role as a filler material as well as an effective crosslinking or insolubilization agent in improving and controlling the membrane performance, i.e., permeation rate and selectivity. (C) 2000 John Wiley & Sons, Inc.