Superhydrophilic/Superoleophobic Mesh/Chitosan-MnO2 Membrane for Robust and Highly Efficient Separation of Oil-in-Water Emulsions

In this study, in order to separate oil-in-water emulsions, superhydrophilic and underwater superoleophobic membrane was prepared, and its fouling resistance during oil-in-water separation was evaluated. Chitosan (derived from shrimp shells)-MnO2 was deposited on the mesh surface by dip coating. The coated membrane was characterized using ATR-FTIR, FE-SEM, water contact angle (WCA), and underwater oil contact angle (OCA) analyses. The results showed that underwater superoleophobicity and superhydrophilicity were achieved successfully. The superhydrophilicity of the chitosan-MnO2-coated membrane was confirmed by WCA = 0. The underwater superoleophobicity of the coated mesh was verified by OCA = 163.5(degrees). The filtration results show that the prepared membrane can separate a wide range of oil-in-water emulsions with separation efficiency >= 99%. The separation efficiency was maintained for thirty cycles. The permeation flux across the membrane was calculated. The flux for n-decane in water emulsion is 190.0 1 m(2) h(-1). Antifouling properties of the chitosan-MnO2-coated membrane were evaluated using dead-end filtration. Also, application of classical models revealed that the fouling mechanism is cake filtration for chitosan-MnO2-coated mesh. The fabricated membrane with chitosan-MnO2 has significant efficiency in separating oil in water from oily effluents.