Fabrication of polypropylene fabric with green composite coating for water/oil mixture and emulsion separation

Superwettable surface for oil/water separation have received great interest due to their high separation selectivity. Nevertheless, the actual application of such material is greatly hampered by poor biodegradablity of the coating and poor durability of the separation substrate. Herein, a novel superhydrophilic and underwater superoleophobic polypropylene fabric (PPF) with regenerated degreasing cotton cellulose/silicon oxide (SiO2) composite coating was successfully fabricated through simple dip coating strategy. The obtained PPF can be utilized as highly efficient membrane material of separating immiscible mixtures of water and oils. Furthermore, by pumping the water-prewetted PPF rolled into a tube, pure and corrosive water on oil is able to be steadily separated without any oil uptake. Especially, owing to the decrease of PPF pores after suffering from the composite coating, a series of oil-in-water (O-in-W) emulsions can be effectively filtrated (separation efficiency: > 92.5%; water flux: > 380.6 L.m(-2).h(-1)). Compared with many filtration materials, the as-fabricated PPF is durable, low cost and the fabrication method can be scaled up for massive production of separation PPF. It is expected that the as-prepared PPF can be applied to deal with oily wastewater from daily life and industries.