Bioinspired Decoration of Superhydrophilic PVDF Membrane with Protruding Nanoparticles for Treatment of Oily Emulsion Wastewater

Effectively removing oily pollutants from wastewater is crucial for environmental protection and reuse of water resources. Preparing membranes based on mussel-inspired chemistry for oil-water separation is a promising method. However, excessive biomimetic deposition could lead to a decrease in permeability of membranes. Herein, superhydrophilic layer has been prepared via the co-deposition of branched poly(ethylene glycol dimethacrylate-co-glycidyl methacrylate) (BPGE) and dopamine on polyvinylidene fluoride (PVDF) membrane surface, following modification with glycerol thiols (MTG) through thiol-ene click and Michael addition reaction. Surface characterization demonstrated the in-situ generation of protruding nanoparticles on the membrane. The modified membranes exhibited superhydrophilicity and underwater superoleophobicity, and achieve high separation efficiency for various oil-water mixtures and oil-in-water emulsions. Besides, the membrane shows excellent reusability in cycling separation experiments. Moreover, the good chemical stability of biomimetic branched coating within certain pH ranges from 5-11 enables the modified membrane with great potential for the treatment of oily industry wastewater