Self-Locked and Self-Cleaning Membranes for Efficient Removal of Insoluble and Soluble Organic Pollutants from Water

A feasible and efficient membrane for long-term treatment of complex oily wastewater is especially in demand, but its development still remains a challenge because of serious membrane fouling and incomplete/destructive reclamation methods. Herein, an interpenetrating TiO2 nanorod-decorated membrane with self-locked and self-cleaning properties is rationally fabricated via coaxial electrospinning and hydrothermal synthesis. The self-locked membrane shows full reinstatement of the original state and exhibits satisfactory mechanical strength, superhydrophilicity, underwater superoleophobicity, and robust solvent resistance, which endow the membrane with successful separation for 16 types of highly emulsified oil-in-water emulsions (e.g., surfactant-free; anionic, cationic, and nonionic surfactant-stabilized). Moreover, successful sequencing treatment of soluble organic emulsions using the separated bait-hook-destroy strategy indicates that the pristine membrane can be used to treat multipollutant wastewater with various limits. Most importantly, the fouled membrane can easily be reinstated by light irradiation without reduction of both mechanical strength and separation performance. As a proof of concept, the as-synthesized membrane shows an ultrahigh flux over 5000 L m(-2)h(-1) with a removal efficiency of >99.92%. The present development would provide a highly efficient strategy for the fabrication of an inorganic-organic revivable electrospinning membrane for various applications.

Automated summary

The study successfully fabricated a TiO2 nanorod-decorated membrane with self-locking and self-cleaning properties, exhibiting good mechanical strength, superhydrophilicity, and underwater superoleophobicity, capable of separating various highly emulsified oil-in-water emulsions and easily restorable by light irradiation. This membrane shows high efficiency in treating multipollutant wastewater.