Robust superhydrophilic depth filter and oil/water separation device with pressure control system for continuous oily water treatment on a large scale

As oily wastewater treatment has emerged as an urgent global issue, oil/water separation using functional filters is attracting significant attention as an environmentally friendly method of oily wastewater purification. Although functional filters based on wetting characteristics have already been developed, it is difficult to use them in the oil/water separation field due to their inability to handle a large amount of wastewater continuously. Herein, a strategy to continuously treat large amounts of oily water for practical application is reported. For the first time, we fabricate a robust superhydrophilic depth filter using a hydrogel material. This filter has great potential for treating large amounts of wastewater because of its large effective area, excellent mechanical and chemical durability, self-cleaning ability and high oil/water separation efficiency. Using this filter, we further develop a device to treat a large amount of wastewater continuously. The promising results demonstrated in this work show the potential applicability of our filter and device in the field of wastewater treatment.