Synthesis of high performance mordenite membranes from fluoride-containing dilute solution under microwave-assisted heating

Abstract

High performance mordenite membranes were successfully prepared in a short synthesis time from fluoride-containing dilute solution without organic template under microwave-assisted heating. The effects of crystallization temperature, fluoride ion and aluminum source on the membrane morphology and separation performance for dehydration of acetic acid by pervaporation were systematically investigated. High performance mordenite membranes with a thickness about 5µm could be prepared from dilute solution with composition of SiO2: 0.06Al2O3:0.24Na2O:0.3NaF:120H2O at 165°C for 4h using various aluminum sources. These mordenite membranes exhibited high fluxes of 0.87±0.06kgm−2h−1 and excellent selectivities, that is only pure water was detected in the permeate side for dehydration of 90wt% acetic acid aqueous mixtures at 75°C. The reproducibility of mordenite membranes was high, using the fluoride-containing dilute solution under microwave-assisted heating, which forebodes a promising prospect for industrial applications in preferential separation of water from acetic acid aqueous solutions.