High-efficient novel super-wetting HKUST-1 membrane for oil-water separation: Development, characterization and performance

In the current work, novel super-wetting HKUST-1 membrane was fabricated via seed-mediated growth method. These HKUST-1 crystal seeds were successfully sprouted on the polydopamine coated stainless steel mesh surface. The characterization results showed that the as-prepared membrane had an excellent superhydrophilic and underwater superoleophobic property because of the presence of polydopamine and HKUST-1 crystal seeds. Meanwhile, the membrane still maintained high separation flux and separation efficiency after high temperature treatment and immersion in different concentrations of acid-base salt solutions, which indicated that the HKUST-1 membrane has excellent thermal stability and chemical stability. The as-prepared membrane also showed remarkable anti-fouling performance and self-cleaning property to crude oil. Moreover, the as-prepared membrane achieved an excellent separation efficiency against four different oil-water mixtures just driven by gravity. The continuous separation tests and oil-water separation in different acid, alkali and salt environments indicated that the as-prepared membrane had an excellent oil-water separation performance for practical applications. The oil-water efficiency was over 99% and the pure water flux was up to 11.1 × 104 L m−2 h−1.