PAF-11/poly (dimethylsiloxane) mixed matrix pervaporation membranes for dealcoholization of aqueous solutions

BACKGROUNDPorous aromatic frameworks (PAFs) have received considerable attention due to their designable framework topologies and high stability. In this work PAF-11 particles were synthesized and incorporated in poly(dimethylsiloxane) (PDMS) matrix for dealcoholation of aqueous solutions for the first time. The effects of PAF-11 loading on the hydrophobilicity, sorption degree, partition coefficient and pervaporation (PV) performance of mixed matrix membranes (MMMs) were studied. RESULTSIt was found that, with the increased PAF-11 loading, the contact angle of MMMs with water increased whereas the sorption degree in water, ethanol and n-butanol declined, demonstrating the improved swelling stability of MMMs. Pristine PDMS and MMMs displayed alcohol sorption-selectivity, and the partition coefficients of ethanol and n-butanol in MMMs increased with PAF-11 loading. In the pervaporation of ethanol and n-butanol aqueous solutions, the MMMs showed an increase in permeation fluxes and separation factor, as well as good stability in long-term running, demonstrating anti-trade-off effects and good application prospects. CONCLUSIONSIt was deduced that, in the pervaporation removal of organics from aqueous solutions, anti-trade-off effects could be fulfilled by introducing hydrophobic fillers with pore sizes larger than molecules of water and organics. (c) 2018 Society of Chemical Industry