Silk fibroin-graphene oxide functionalized melamine sponge for efficient oil absorption and oil/water separation

Abstract

Various oil and organic solvent spill accidents have resulted in severe environmental issues. Thus, hydrophobic sorbents have drawn much attention for oil spill cleanup. An oil/water separation material with robust mechanical properties was developed by modifying melamine sponge with silk fibroin-graphene oxide (SGMS). Here, silk fibroin was used as a molecular binder to combine graphene oxide and the melamine sponge. After modification, the surface of the sponge became hydrophobic. The SGMS exhibited excellent oil adsorption capacity (up to 76 times its own weight), efficient oil-water separation, good mechanical properties (100 cycles), and superior recyclability (50 times). Moreover, SGMS can be used in the separation of surfactant-stabilized oil/water emulsions with excellent separation efficiency and for the continuous separation of oil/water in a pumping state. These excellent properties indicate that SGMS can be industrially produced and is suitable for the adsorption of organic pollutants under realistic conditions.