Preparation and oil-water separation performance of superhydrophobic melamine sponge composite materials

Oily wastewater discharge and offshore oil spill accidents occur frequently, and conventional oil-water separation methods exhibit certain limitations. Therefore, the adsorption separation method is adopted for oil-water separation.A superhydrophobic and oleophilic sponge was prepared with melamine sponge as the substrate via dopamine-inspired self-polymerization, in-situ loading of ZIF-8 and hydrophobic modification with hexadecyltrimethoxysilane (HDTMS). The water contact angle reached 158.9°. The static adsorption amounts of soybean oil, diesel, n-hexane, cyclohexane, toluene, dichloromethane, and chloroform were 53.4 g/g, 65.3 g/g, 49.8 g/g, 57.7 g/g, 61.4 g/g, 89.8 g/g, and 105.8 g/g, respectively. The oil-water separation efficiency reached 98.5%, and no obvious performance degradation was observed after 10 adsorption–desorption cycles. To enhance structural stability and oil retention capacity, the modified sponge was encapsulated with polypropylene (PP) melt-blown nonwoven material and edge-sealed by ultrasonic bonding. The composite exhibited a saturated adsorption capacity of 55.9 g/g for soybean oil and an oil retention rate of approximately 85%.This material possesses a facile and fluorine-free green fabrication strategy, exhibiting promising application prospects in oil-water separation and oil spill remediation.