Effective separation of oil and water mixture using hydrophobic g-C₃N₄ coated natural rubber foam

Frequent oil spills are a major contributor to water pollution, leading to numerous environmental and ecological issues and posing risks of fire and explosions. Hence, there is an imperative to develop a cost-effective and exceptionally functional absorbent material for separating oil and water. In this study, a simple, low-cost, environmentally friendly, biodegradable, highly hydrophobic, and super oleophilic graphitic carbon nitride (g-C₃N₄) based natural rubber foam is introduced for oily wastewater treatment. The g-C₃N₄ was coated onto the natural rubber foam using a simple dip-coating method. The resulting hydrophobic g-C₃N₄-coated foams exhibit highly hydrophobic and superoleophilic surface properties with contact angles of 144.1 ± 2° and 0°, respectively. These foams exhibited more than 100% oil absorption capacity, effectively absorbing a variety of oils and solvents like olive oil, acetone, methanol, ethanol, etc. and successfully separating oil and solvent mixtures from water. Hence, the developed g-C₃N₄-based natural rubber foam absorbent has excellent potential for oil/water separation applications.