Preparation of high-performance zeolite membrane on a macroporous support by novel intermittent hydrothermal synthesis

Abstract

Constructing high-quality zeolite membrane by regulating solely the kinetics of zeolite nucleation and growth is desired because of its simplicity and potential industrial viability. Herein, a high-performance mordenite membrane was prepared without using organic template successfully on a macroporous tubular α-alumina support using a novel and simple intermittent hydrothermal synthesis (IHS) method. We aimed at regulating membrane synthesis kinetics by adjusting the concentration of the synthetic gel by introducing an unheated period of the oven in the middle stage of the synthesis process. In the proposed IHS method, the power supply of the oven can be switched off and on with the aid of a smart socket without manual operation, ensuring its feasibility and convenience. A thin and dense membrane layer was formed via the appropriate adjustment of presynthesis time, unheated time, and resynthesis time. The effects of each duration on the morphologies, microstructures, and pervaporation performances of the prepared mordenite membranes were investigated. Under optimized conditions, the as-synthesized mordenite membrane showed high pervaporation performance with a permeation flux and separation factor of 5.57 kg m−2 h−1 and >10000, respectively, in the dehydration of 90 wt% isopropanol/water mixture at 75 °C. This work provides a novel, simple, and feasible method for the preparation of high-performance zeolite membrane.