Thin film composite polyamide membrane for removal of pharmaceuticals from treated sewage effluent

Pharmaceutical contamination in water is an emerging global concern due to its adverse impacts on human health and aquatic ecosystems. Cyclophosphamide (CP), an anticancer drug, is frequently detected in hospital effluents and is among the most common antineoplastic contaminants. In this study, novel thin-film composite (TFC) polyamide (PA) membranes were fabricated via interfacial polymerization by incorporating acacia gum (AG), a natural amphiphilic additive, into the active layer to enhance the removal of CP and other pharmaceuticals from water. The membranes were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), x-ray photoelectron spectroscopy (XPS), zeta potential and water contact angle analyses. AG incorporation improved membrane porosity, hydrophilicity, and negative surface charge due to its amphiphilic structure containing hydrophilic polysaccharides and hydrophobic proteinaceous moieties. Filtration experiments using synthetic wastewater and real treated sewage effluent (TSE) spiked with CP, acetaminophen, and atenolol demonstrated that AG-containing membranes achieved CP rejection up to 98.7%, compared to 90.4% for pristine PA membranes, while maintaining higher water flux. The modified membranes also outperformed commercial NF90 and NF270 membranes. Furthermore, AG-containing membranes exhibited enhanced antifouling performance, reducing bacterial adhesion by more than 55%, demonstrating strong potential for sustainable pharmaceutical wastewater treatment applications.