Developing a versatile and resilient PVDF/CeO2@GO-COOH photocatalytic membrane for efficient treatment of antibiotic-contaminated wastewater

Abstract

This study focuses on enhancing the performance of PVDF membranes by incorporating CeO2 photocatalyst in combination with carboxyl-functionalized graphene oxide (GO-COOH). The carboxyl groups of GO-COOH serve a dual purpose: providing anchoring sites for CeO2 and enhancing the interfacial interaction with the polymer. The PVDF/CeO2@GO-COOH membranes were fabricated using sequence of physical blending and phase inversion processes, resulting in significantly improved internal structure with an average pore size diameter of 1.20–1.35 nm. Moreover, the CeO2@GO-COOH photocatalyst exhibited superior compatibility with PVDF. The as-prepared PVDF/CeO2@GO-COOH photocatalytic membranes (PMs) demonstrated remarkable photocatalytic activity, outperforming PVDF/CeO2, achieving degradation efficiencies of 85.55 % for ciprofloxacin and 84.82 % for sulfanilamide (both at 20 mg/L) under UV irradiation for 150 min. Photo-filtration experiments confirmed the synergistic effect of molecular separation and photodegradation, resulting in the removal of 99.5 % of ciprofloxacin and 79.5 % of sulfanilamide, coupled with a relatively high pure water flux of 115.44 L.m−2.h−1. The PM also exhibited excellent stability, self-cleaning properties, and reusability, with a flux recovery rate (FRR) of 97.5 % after five cycles of use. Finally, the PVDF/CeO2@GO-COOH membrane holds great promise for the treatment of pharmaceutical industry wastewater, offering a comprehensive solution that combines efficient pollutant degradation, high permeate flux, stability, and reusability.