A two-step hydrophobic fabrication of melamine sponge for oil absorption and oil/water separation

Hydrophobic sponges have drawn great attention recently as potential absorption materials for oil spill cleanup and water/oil separation due to their excellent elasticity, absorptivity and selectivity. Herein, we demonstrate a facile and cost-effective method to fabricate hydrophobic sponges based on commercial melamine sponge via a two-step process, i.e., silica nanoparticle adsorption and silanization covering procedures. The hydrophobic modification was confirmed by ATR-FTIR and SEM characterization. The modified sponge shows hydrophobicity and oleophilicity and exhibited excellent absorption capacity for various oils and organic solvents (60-109 g/g). Interestingly, this modified sponge displays great endurability towards ultrasonication or at acid/alkali circumstance, and presents remarkable reusability after 12 cycles of absorption-squeezing process. In addition, a piece of modified sponge can be employed for continuous collecting of oil/solvent from water by using a simple collection device. These hydrophobic, elastic, and durable melamine sponges are very promising materials for practical oil absorption and oil/water separation.