Electron beam irradiation of polyvinylidene fluoride/polyvinylpyrrolidone ultrafiltration membrane in presence of zwitterions molecules evaluation of filtration performances

摘要

In this research, the commercial PVDF/PVP membrane was irradiated at 10 and 100 kGy with electron beam (EB) to improve its fouling resistance capacity. Membrane irradiation was conducted in the presence of zwitterionic molecules (L-Cysteine, Phosphocholine) and with 2-(Dimethylamino)ethyl methacrylate). The main goal was to investigate the impact of irradiation in presence of zwitterions on the modification route of PVP within the polymer blend and to relate it to filtration performances. Globally, EB irradiation enhanced the membrane's filtration performance but this improvement cannot be sustained after several filtration cycles. Membranes irradiated with the lower absorbed dose (10 kGy) displayed higher permeate flux and lower cake resistance than membranes irradiated with the 100 kGy dose. The best sustainable anti-fouling capacity was observed for the membrane irradiated with 10 kGy in the presence of L-Cysteine. Membrane characterization showed that the membrane surface was modified by EB irradiation, with features such as smoother surface, modification of PVP and increased amount of crosslinking emphasizing the potential formation of PVP hydrogels. Despite obvious changes observed on membrane surface depending on the chosen compounds used for irradiation, membranes' analyses failed to identify sulphur, phosphorous grafted moieties. From this study, it is confirmed that membranes EB irradiation in presence of zwitterionic molecules is a promising technique to modify the PVDF/PVP blended polymer.