Porous BPPO-based membranes modified by multisilicon copolymer for application in diffusion dialysis

Brominated poly(2,6-dimethyl-1,4-phenylene oxide) (BPPO)-based hybrid membranes are produced from phase inversion, partial hydrolysis, modification with multisilicon copolymer of poly(MA-co-gamma-MPS) and quaternization processes. The membranes have a porous structure, as revealed by SEM observation and water flux measurement. The modification by poly(MA-co-gamma-MPS) introduces -Si-O-Si network in the BPPO matrix, and hence the membrane swelling resistance in 65 degrees C water is enhanced. The membranes are taken for diffusion dialysis (DD) process to recover HCl from HCl/FeCl2 solution. The dialysis coefficients of HCl(U-H) are in the range of 0.020-0.025 m/h at 25 degrees C and the separation factor (S) can reach up to 45.5. The high permeability and selectivity are due to the unique membrane structure and the presence of different functional groups. (C) 2013 Elsevier B.V. All rights reserved