Stable Superhydrophobic MOF-5@polydopamine@melamine Sponge for Efficient Continuous Oil–Water Separation and Emulsion Purification

Frequent oil spill incidents and increasing amounts of industrial wastewater pose a serious threat to the environment. The use of superhydrophobic materials to separate oil/water mixtures has attracted widespread attention. In this work, a superhydrophobic sponge based on MOF-5 was prepared to achieve efficient continuous oil–water separation and emulsion purification. HDTMS-MOF-5@PDA@MS (H-MOF-5@PDA@MS) not only exhibited superhydrophobic property (WCA = 153.8°, SA = 6.5°) but also exhibited excellent saturated adsorption capacity, with an oil adsorption capacity of 66 (petroleum ether)-168 (chloroform) g/g and oil–water separation efficiency of 99.2%. It also demonstrated efficient performance in various emulsion purification processes. Furthermore, it maintained a stable superhydrophobicity in some extreme environments. H-MOF-5@PDA@MS is expected to have wide application perspective in the fields of environmental pollution control and wastewater treatment due to its low cost, simple process, excellent oil–water separation efficiency, reusability, and environmental friendliness.