Facile fabrication of fabric-based membrane for adjustable oil-in-water emulsion separation, suspension filtration and dye removal

Special wettability fabrics-based membranes have shown excellent performance in emulsified oil/water separation, however, their application in separating industrial oil-in-water emulsions still remains a great challenge due to the complexity of multifarious surfactant components. In this work, we demonstrate a simple and facile approach to fabricate fabric-based membranes (P(AM-DMC-AA)@CFs) for complex emulsified oil/water (printing and dyeing wastewater) separation with combining the advantage of amphoteric polyacrylamide layer and cotton fabric in a single system. The amphoteric polyacrylamide surface and tortuous fabric channels synergistically provide the membranes with demulsification adjustability for separating emulsified oil in water which stabilized by anionic/cationic surfactants. Meanwhile, the incorporating of amphoteric polyacrylamide into cotton fabrics had remarkable advantages of both flexible and stable superhydrophilic/underwater superoleophobic. Consequently, the obtained P(AM-DMC-AA)@CFs membranes are endowed with robust superhydrophilicity, underwater superoleophobicity and switchable zeta potential, which make it capable of highly efficient separation of oil/water emulsion (anionic: 94.05%, cationic: 96.19%), suspension filtration (kaolin: 89.5%, hematite: 93.1%,) and concurrent dye removal in 5 min (14.3 mg/g). In addition, the prepared membrane is still effective in separating simulated printing and dyeing wastewater containing multiple pollutants. The facile and versatile design of the P(AM-DMC-AA)@CFs membrane offers new prospects for exploiting fabric-based membranes with extraordinary features for industrial oily wastewater treatment.