Rationally regulating the PES substrate by introducing ZIF-8 with tunable shapes for optimal thin-film composite membrane

Abstract

The property of the substrate takes a critical role in the separation performance of the thin-film composite (TFC) membrane. While, regulating the properties of the substrate by introducing metal–organic framework with tunable shapes for optimal TFC membrane has not been studied in-depth. In this work, a rationally regulated polyethersulfone substrate was designed by embedding ZIF-8 with three different shapes (spherical, hollow tube and flowerlike). Then, the TFC membranes were obtained by synthesising polyamide layer on the modified substrates. The results show that the modified substrates have positive effect on the water treatment performance, which was highly related to the addition amount and shapes of ZIF-8. Specifically, the hollow tube ZIF-8 modified TFC membrane exhibits the best water permeance of 2.22 L m-2h−1 bar−1(LMH bar−1) and excellent rejections (94.2 %, 99.7 %, 99.8 %, 99.9 % for NaCl, AO, MO and DR, respectively), which mainly derived from the increased channels and surface roughness. The findings provide a comprehensive insight of the shape-controlled substrate in the separation performance of the TFC membranes.