In situ separation of chemical reaction systems based on a special wettable PTFE membrane

Oil–water separation is a worldwide subject because of the increasing demands in numerous applications, involving separation of immiscible products from chemical reaction systems in synthetic industry. Owing to the limitations of low efficiency, high energy consumption, and multiple operations in conventional methods, membranes with special wettability have been widely developed in recent years to effectively separate various oil–water systems. However, few works on treating chemical reaction systems have been reported because of the lack of stability of current membranes in harsh environments, especially during long-term work. Herein, a continuous in situ separation of chemical reaction systems based on a special wettable porous polytetrafluoroethylene membrane is successfully conducted. The membrane possesses (1) an intrinsic (with no modification) special wettability of highly hydrophobic/oleophilic in air and superoleophilic under water and 2) an excellent long-term durability in acidic, alkaline, saline, organic, or heating environments. The in situ separation process exhibits both large separation flux (>3500 L m⁻² h⁻¹) and high product purity (>99.00%) by continuously filtering synthetic products without interrupting chemical reactions, which is of great significance in industrial fields.