High-Throughput Membrane Surface Modification to Control NOM Fouling

A novel method for synthesis and screening of fouling-resistant membrane surfaces was developed by combining a high-throughput platform (HTP) approach together with photoinduced graft polymerization (PG P) for facile modification of commercial poly(aryl sulfone) membranes. This method is an inexpensive, fast, simple, reproducible, and scalable approach to identify fouling-resistant surfaces appropriate for a specific feed. In this research, natural organic matter (NOM)-resistant surfaces were synthesized and indentified from a library of 66 monomers. Surfaces were prepared via graft polymerization onto poly(ether sulfone) (PIES) membranes and were evaluated using an assay involving NOM adsorption, followed by pressure-driven filtration. In this work new and previously tested low-fouling surfaces for NOM are identified, and their ability to mitigate NOM and protein (bovine serum albumin)fouling is compared. The best-performing monomers were the zwitterion [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide, and diacetone acrylamide, a neutral monomer containing an amide group. Other excellent surfaces were synthesized from amides, amines, basic monomers, and long-chain poly(ethylene) glycols. Bench-scale studies conducted for selected monomers verified the scalability of HTP-PGP results. The results and the synthesis and screening method presented here offer new opportunities for choosing new membrane chemistries that minimize NOM fouling.