Superwetting polyethersulfone membrane functionalized with ZrO2 nanoparticles for polycyclic aromatic hydrocarbon removal

Polycyclic aromatic hydrocarbons (PAHs) are persistent and widespread in the aquatic environment, causing potential hazards for human health. In this study, a superwetting and robust PES-PAA-ZrO2 nanofiltration membrane was proposed through surface modification for PAH removal with high efficiency. A ZrO2 coating was formed on polyethersulfone (PES) membrane surface through chemical bonding, thus the PES-PAA-ZrO2 membrane exhibited super-hydrophilicity, under-water oleophobicity, and excellent stability. In comparison with the original PES membrane, the water contact angle of the modified membrane was significantly decreased from about 50° to less than 10°, and quickly dropped to 0° within 1 s. This provided a much lower energy barrier for water permeation due to its super-high water affinity. The wastewater treatment efficiency was increased by about 4 times after modification with more than 90% of PAH rejection rate. The excellent robustness of PES-PAA-ZrO2 membrane was verified under various conditions, which gave the membrane practical potential for long-term operation.