A renewable and biodegradable all-biomass material for the separation of oil from water surface

Abstract In this work, superhydrophobic and superoleophilic loofah sponge (LS) was prepared by a facile, inexpensive, eco-friendly and sustainable dip-coating method. This method uses LS as the porous skeleton, carnauba wax (CW) and rice bran wax (RW) as the coating material and ethyl acetate as the solvent. The wax layer forms particle/film composite micro-structures, which makes the superhydrophobic coating have excellent stability against soaking of water and various oils, and high resistance to corrosive mediums. The superhydrophobic and superoleophilic LS can selectively separate oil from water surface with desirable properties, such as high separation capacity (>9.5 g/g), efficiency (>91%), and reusability (>10 cycles). In addition, the used SLS can be reused for the recovery of waxes and LS substrate. Furthermore, the LS substrate can be biodegraded in the natural ecological cycle. The present work provides a new idea and solution for developing sustainable, renewable and biodegradable all-biomass oil/water separation materials.