A high flux continuous thin UiO-66-NH2 membrane (CTUM) for rapid dyes separation

Abstract

Separation membranes with high solvent permeation and rejection are attractive for energy conservation in waste solvents separation. Herein, ultra-high flux dye separation membrane was firstly obtained by in situ growing continuous thin MOF membranes on commercial non woven fabrics, which overcome the “trade-off” effect of traditional separation membranes. The continuity of MOF membrane is closely related to the grafting density of maleic anhydride (MAH), and the thickness and surface morphology of continuous thin UiO-66-NH₂ membrane (CTUM) can be controlled by tuning reaction time. The CTUM exhibits a molecule weight cut-off of 950 Da and organic solvents permeation of > 2200 L m⁻²h⁻¹ bar⁻¹ with the rose bengal (RB) rejection of 99.39 %. The selectivity of CTUM depends on the size screening and electrorepulsion effect, and the permeation of CTUM is at least 10 times higher than conventional separation membranes. Meanwhile, the CTUM is durable under mechanical friction and during filtration. Our work represent a reliable way to make durable MOF membranes for ultra-high permeation organic solvent filtration, which lay a foundation for further exploration of high performance separating membranes.