Induced Synthesis of an Al-Based CAU-10 Tubular Membrane for the Highly Efficient Separation of MeOH/MTBE by Pervaporation

Abstract

The preparation of stable metal−organic framework tubular membranes for liquid mixture separation has always been a tough problem. Herein, a flexibly prepared, continuous, and stable Al-based CAU-10 membrane with ceramic tubes as support was developed by a thin γ-Al 2 O 3 layer induction method and employed for the first time in the separation of MeOH/MTBE azeotropic mixtures through pervaporation. The γ-Al 2 O 3 layer introduced on the tube by the dip-coating technique not only facilitated the crystal nucleation and continuous growth of CAU-10 membranes but also reinforced the membrane stability by acting as anchoring sites between the membrane and the substrate. The as-prepared CAU-10 tubular membrane exhibited excellent separation performance for MeOH/MTBE mixtures owing to its suitable pore size and good hydrophilicity. For the separation of 14.3 wt % MeOH/MTBE azeotropic mixtures, the membrane displayed a permeation flux of 1.76 kg/(m 2 h) and a high separation factor of 2041 at 50 °C, which is better than most of the membranes reported for the pervaporation separation of MeOH/MTBE mixtures. More excitedly, the CAU-10 tubular membrane continued to be tested for more than 7 days without any obvious change in pervaporation performance, demonstrating its outstanding operational and hydrothermal stability. Accordingly, the CAU-10 tubular membrane would be a promising alternative to separate the MeOH/MTBE azeotropic mixtures due to its easy preparation, high performance, and excellent stability.

Synergistic Preparation of Stable Al-Fum Based Tubular Membrane for Pervaporation Separation of Water–Ethanol–Ethyl Acetate Azeotropic Mixtures

“…Pervaporation is an efficient membrane separation technology for liquid mixture that uses the difference in partial pressure between the two sides of the membrane as the driving force and favorably separates azeotrope and close-boiling components according to their physicochemical properties. , Due to its advantages of being energy saving, environmentally friendly, and low cost, pervaporation has attracted more and more attention in recent years. − As a result, it has been widely employed for dehydration of organic mixtures, , recovery of low concentration organic compounds, , and separation of organic–organic mixtures. , …”