Preparation of pervaporation membranes by interfacial polymerization for acid wastewater purification

A series of acid-resistant polysulfonamide/polyethersulfone composite pervaporation (PV) membranes were prepared by interfacial polymerization. The aqueous phase was a mixed solution containing m-phenylenediamine (MPD) and triethylenetetramine (TETA), and the organic phase was a 1,3-benzenedisulfonyl chloride (BDSC) n-hexane solution. Acid resistances of the composite membranes were assessed by attenuated total reflection Fourier transform infrared spectrometer (ATR-FTIR), energy dispersive spectrometer (EDS) and weight loss tests after being soaked in 20 wt% H2SO4 solution. The composite PV membrane exhibited a water flux of 10.1 kg/(m(2).h) and NaCl rejection> 99.3 % when separating an aqueous solution with 3.5 wt% NaCl at 75 degrees. After soaked the membrane in 20 wt% H2SO4 solution for one week, the salt rejection did not decline. Moreover, water flux was stable over a 600 min PV test using a 10 wt% H2SO(4) solution as feed at 75 degrees. To our best knowledge, this is the first report of acid-resistant PV desalination membrane. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.