MnO2-modified PEEK membrane for efficient oil-water separation and solar-assisted seawater desalination

Abstract

Economic and efficient routes to achieve clean freshwater from oil-water mixtures and seawater have gained special attention to reduce the current water crisis, but still a challenge unsolved. Herein, poly (ether ether ketone) (PEEK) membrane, modified with MnO2 layer, has been prepared by facile hydrothermal method to address this issue aforementioned. Given the existence of PEEK and underwater superoleophobicity/underoil superhydrophilicity of MnO2, the composite membrane exhibits strong mechanic properties (tensile stress: 110.2 MPa) and high separation efficiencies (99.9 %) for different oil–water mixtures under gravity. Additionally, our membrane could also effectively separate immiscible oil mixtures according to the dipole–dipole interaction. Furthermore, firm chemical stability against dichloromethane, N, N-Dimethylformamide, 1 M NaOH, 1 M HCl, and 1 M NaCl has been achieved. Most importantly, our membrane displays durable evaporation efficiency (2.63 kg m-2h−1), high energy efficiency (85.9 %), and super salt tolerance under 1 sun irradiation, for solar-assisted seawater desalination.