Adjustable pervaporation performance of Zr-MOF/poly(vinyl alcohol) mixed matrix membranes

摘要

BACKGROUND Polymer membranes often display trade-off effects between permeation flux and separation factor in pervaporation, and exploring the strategies for breaking the effects is crucial. In this study, by altering the organic linkers (1,4-benzenedicarboxylate acid, 2-hydroxyterephthalic acid, 2,5-dihydroxyterephthalic acid and biphenyl-4,4-dicarboxylate), UiO-66, UiO-66-OH, UiO-66-(OH)(2) and UiO-67 were prepared and incorporated in poly(vinyl alcohol) (PVA) membranes for pervaporation of 90 wt% ethanol solution for the first time. RESULTS The membrane properties and pervaporation performances were tuned, and anti-trade-off effects were demonstrated for UiO-66/PVA, UiO-66-OH/PVA and UiO-66-(OH)(2)/PVA mixed matrix membranes (MMMs). For the UiO-66-(OH)(2)/PVA MMM with 1.0 wt% loading, the permeation flux, separation factor and pervaporation separation index (PSI) were increased by 16, 14 and 32% respectively and the water permeance and selectivity were increased by 24 and 10% respectively, while the swelling degree in 90 wt% ethanol declined by 28% in comparison with that of pristine PVA membrane. CONCLUSION The pervaporation performance of the UiO-66-(OH)(2)/PVA MMM demonstrated good potential in alcohol dehydration. (c) 2018 Society of Chemical Industry