Enhancing the antifouling and rejection properties of PVDF membrane by Ag3PO4-GO modification

Ultrafiltration is an environmentally friendly water treatment technology, but membrane fouling significantly impacts membrane performance and service life. Photocatalytic modification of membrane is regarded as an effective way for membrane fouling control. In this study, graphite oxide (GO), Ag3PO4 and Ag3PO4-GO nanomaterials were applied in polyvinylidene fluoride (PVDF) ultrafiltration membranes modification, and the membranes was denoted as P-GO, P-AgP and P-AgP@GO, respectively. Filtration of humic acid (HA) at different operating conditions was adopted in evaluation of membrane performance. Among them, P-AgP@GO had the best permeation, rejection and antifouling performances, and could maintain excellent properties when operation conditions (HA concentration, operation pressure, pH and ionic strength) were changed. Furthermore, the effect of photocatalysis on the self-cleaning performance and its mechanism were revealed. The overall performance of P-AgP@GO could be enhanced by visible light irradiation, and extending the visible illumination time during the filtration was conducive to the reusability. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

In this study, PVDF ultrafiltration membranes were modified using graphite oxide, Ag3PO4, and Ag3PO4-GO nanomaterials, with the P-AgP@GO membrane demonstrating the best performance and excellent stability under different operating conditions. Photocatalysis can enhance the self-cleaning performance of the P-AgP@GO membrane, and prolonging visible light irradiation time contributes to membrane reusability.