Rational design of multifunctional membrane material with underwater superoleophobicity for dye contaminated emulsion separation

Ecofriendly production of membranes with excellent antifouling, surface wettability and reusability characteristics is highly desired. Polyelectrolyte based membranes with superhydrophilic and underwater superoleophobic properties have demonstrated outstanding separation performance of high-viscous oil contamination in waterborne because of anti-oil-fouling properties. Hence, we reported on a rational design for the fabrication of multifunctional membrane materials with a polyelectrolytic nature for oil/water emulsion separation, and dye mixed with emulsion separation. The multifunctional membrane material formed by intercalating through carrageenan (CGN) mixed with nanoclay laponite (LP), and its surface functionality was altered by the addition of Tannic acid (TA) for effective cross-link formation. The obtained multifunctional membrane (TA@CGN-LP) material was coated on filter paper for emulsion and methylene blue dye mixed with emulsion separation by filtration. The TA@CGN-LP coated membrane shows a superhydrophilic property with an underwater oil contact angle of 150° for crude oil and water contact angle of 40° in air. Polyelectrolytes of the surface functional groups on the TA@CGN-LP membrane offer emulsion separation efficiency of 99.8% and flux rate of approximately 1721 Lm -2 h −1 bar -1 . The obtained composite materials have promising multipurpose applications as an ecofriendly, green membrane fabrication material for simultaneous removal of various types of water pollutants. • Eco-friendly fabrication of multifunctional membrane materials from κ-Carrageenan intercalated with nanoclay laponite, crosslinked by tannic acid coat (TA@CGN-LP). • Polyelectrolyte nature of TA@CGN-LP exhibited with excellent anti-oil-fouling for high-viscous crude oil and self-cleaning ability. • TA@CGN-LP shows good underwater superoleophobic nature with high underwater oil contact angle. • Oil-in-water emulsion and MB dye mixed emulsion was effectively separated by TA@CGN-LP membrane with 99.8% of efficiency. • Bio-inspired multifunctional membrane materials have goodseparation efficiency with high flux upon the emulsion separation.