Superior mechanically orthogonal woven fabric membrane with tunable wettability for on-demand oil-water separation

To date, oil spills and massive discharges of oily wastewater have deeply negative impacts on global water ecosystems. Superwetting membranes have emerged as a promising candidate for oil/water separation due to the merit of high efficiency and low energy-consumption. However, single wettability membranes are difficult to cope with complex and variable environmental conditions. Herein, a novel orthogonal woven fabric membrane (JC-R) with tunable wettability and mechanical property have been reported based on the woven structure design and yarn functionalization. The JC-R exhibited excellent pH responsiveness, namely quickly switching its wetting properties between the hydrophobic and hydrophilic by simple acid/base adjustments. Compared to cotton fabric, the JC-R demonstrated enhanced bursting strength (1421 N), offering robust support for oil-water separation. The inherent properties of the JC-R enabled on-demand separation of a wide variety of oily wastewater, including oil-water mixtures with different oil densities and types (separation efficiency >98 %), oil-in-water emulsions and water-in-oil emulsions, exhibiting its excellent reusability. The work might provide new insights in oily wastewater purification.