Insight into the Performance of Polypropylene-Based Fibrous Filters with Polyvinylimidazole Grafted Surfaces for Separation of Nonsteroidal Drugs in an Aqueous Medium

Abstract To address global NSAID water pollution, an imidazolium ion-rich adsorption membrane (PPF–PVI) was fabricated via simple one-step UV grafting of vinylimidazole on meltblown fabric. Benefiting from the open porous substrate, the resultant PPF–PVI exhibited a water flux up to 62,100 L/m2·h at a low pressure of 1.5 kPa, while the grafted functional chains imparted a maximum DCF adsorption capacity of 82.9 mg/g. Driven by electrostatic interactions, PPF–PVI selectively enriches NSAIDs from aqueous mixtures with a separation factor as high as 80.6. Efficient desorption can be achieved by switching pH, while the robust covalent grafting ensures superior acid–alkali stability throughout the entire adsorption–desorption process. The PPF–PVI membrane retained its performance (>95%) for 10 cycles of adsorption-elution even under true river water conditions. Excellent selectivity, high permeability, and unique stability of the PPF–PVI demonstrate a pathway for remediation of water contaminated by NSAIDs and recovery of the drugs.