Performance investigation of Fe3O4 blended poly (vinylidene fluoride) membrane on filtration and benzyl alcohol oxidation: Evaluation of sufficiency for catalytic reactors

Abstract

Fe3O4-PVDF membranes were prepared by blending of magnetic Fe3O4 powders with polyvinylidene fluoride to investigate whether those were usable or not in catalytic membrane reactors. Filtration performances and catalytic activity of membranes in microwave conditions were measured in separate processes. Composite Fe3O4-PVDF membranes were characterized by TG-DTA, FTIR, XRD, SEM and contact angle techniques. Disappearing of alpha-phases at PVDF was observed with increasing amount of additives from XRD diffraction patterns. Decomposition of polymer fastened due to catalytic effect of Fe3O4. Finger-like structures and large number of small pores were observed at the SEM images. Those provided effective transportation of substrate among the active sites of catalyst. At the experiments conducted in batch reactor, 51%, 77%, 66% and 63% benzyl alcohol conversion were recorded for 2%, 4%, 6% and 8% Fe3O4-PVDF composite pieces respectively. Catalyst were separated magnetically and reused several times. On the other hand Fe3O4 blended PVDF membranes provided improved flux and BSA rejection compared with performance of bare PVDF membrane: 41.6% BSA rejection was obtained with 4% Fe3O4-PVDF whereas it was only 6.7% for PVDF. Fe3O4-PVDF composites performed high activity for the benzyl alcohol oxidation in batch reactor and also better filtration at filtration cell. These results promise to obtain practical and low cost membrane material for catalytic reactors usable in microwave support to get fast results. (C) 2018 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.