Synthesis of mesoporous SiO2 xerogel/chitosan mixed-matrix membranes for butanol dehydration

Novel mesoporous SiO2 xerogel/chitosan (CS) mixed-matrix membranes (MMMs) were successfully prepared by incorporating sol-gel synthesized SiO2 xerogels into glutaraldehyde (GA) cross-linked CS membranes. The effects of the SiO2 doping amount and the feed temperature on the performance of the separation of butanol and water was also investigated in this study. The 0.25 wt% SiO2 xerogel/CS MMMs possessed the best pervaporation performance and the largest PSI value of 1102 kg/m(2)h with a permeate flux of 736 g/m(2)h (Permeability of 3.25 x 10(-5) g m m(-2) h(-1) Pa-1) and a separation factor of 1498 at a feed temperature of 50 degrees C. This PSI value is not only comparable but also exceeds that of other membranes reported in the literature. The separation factor and the flux of the SiO2 xerogel/CS MMMs in this study clearly exceed the upper limit of the previously reported MMMs. As a result, the as-prepared novel SiO2 xerogel/CS MMMs showed an improved performance during the butanol and water separation process, which raises the possibility of future pervaporation applications using this novel SiO2 xerogel/CS MMMs. (c) 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.