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 MnO 2 layer, has been prepared by facile hydrothermal method to address this issue aforementioned. Given the existence of PEEK and underwater superoleophobicity/underoil superhydrophilicity of MnO 2 , 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 -2 h −1 ), high energy efficiency (85.9 %), and super salt tolerance under 1 sun irradiation, for solar-assisted seawater desalination.
Fan Yang,Su Li,Hongyan Qi,Weibo Sun,Jinbao Li,Mei Zhang,Zheng Chen,Jinhui Pang,Zhenhua Jiang
Although poly (ether ether ketone) (PEEK) exhibits excellent solvent resistance , it could not be prepared directly by non-solvent induced phase separation (NIPS) method due to its poor solubility. Herein, PEEK porous membranes were successfully fabricated by combining NIPS and acid hydrolysis. The superhydrophilic thermo-responsive poly (N-isopropylacrylamide) (PNIPAm) polymer was in-situ grafted on the PEEK membrane surface via the UV grafting polymerization and improved the membrane interface hydrophilicity, making the membrane water contact angle changed from 89.5° to 0° at 25 °C. After heating the membrane surface to 40 °C, the membrane exhibited hydrophobicity (100°), realizing the thermo-responsiveness via switching the temperature. Furthermore, due to the transferred membrane wettability at different temperatures, PEEK-g-PNIPAm could separate different types of oil-bearing systems with high rejection above 99.0 %. What’s more, the PNIPAm layer also enhanced the membrane anti-fouling capacity. Benefiting from the extraordinary solvent resistance of the PEEK matrix, PEEK-g-PNIPAm maintains its intact morphology after 6 h immersion in various organic solvents , addressing the commonly reported problem of polymer membranes having certain solubility in solvents. The PEEK-based membranes with excellent solvent resistance could be useful in the oil-bearing separation.
危险品化学品经营许可证（带存储）