Preparation of antifouling zwitterion PVDF-imprinted composite membranes for selective antibiotic and oil/water emulsion separation

Molecularly imprinted composite membranes are considered to be a promising technology for the selective separation of antibiotics in wastewater. However, membrane pollution still greatly limits the practical applications of these membranes, especially in oily wastewater. In this study, an anti-fouling zwitterion PVDF-imprinted composite membrane (SPICM) was synthesized using dopamine as the functional monomer and crosslinking agent in the imprinting process. First, sulfobetaine 8 was blended with a porous PVDF membrane via a surface segregation strategy. Next, dopamine self-polymerization provided effective recognition sites and endowed the membrane surface with high hydrophilicity. The SPICM used for emulsion separation and selective tetracycline hydrochloride (TC) in wastewater. The as-prepared SPICM was able to separate various emulsions under gravity with a high flux (626 L m(-2) h(-1)) and separation efficiencies of up to 99%. This membrane achieved a TC separation efficiency of 88.3% in oily wastewater. Therefore, the design of SPICMs with good antifouling performance provides a new strategy for the highly selective separation of active components from oily wastewater.