A review on zeolitic imidazolate framework-8 based materials with special wettability for oil/water separation

Oil/water separation plays a critical role in treating oily wastewater arising from oil exploitation, oil spill accident and catering oily wastewater. Effective separation of oily wastewater is a key issue in environmental protection. Notably, zeolitic imidazolate framework-8 (ZIF-8) has attracted significant attention in the field of oil/water separation due to its hydrophobic, super oil-wet boiling, and adjustable porosity properties. The present review emphasizes the recent innovation on super-hydrophobic methods for ZIF-8-based materials for oil-water separation. Strategies for fabrication methods of ZIF-8-based separation materials on in-situ growth, secondary growth and electrospinning are discussed. Subsequently, membrane and adsorption separation through ZIF-8-based membranes and foams for oil-water mixture and emulsions are systematically discussed. Finally, the challenges faced by ZIF-8 composites in practical applications are briefly discussed, and the future development direction in the research of cost-efficient approach to produce superhydrophobic ZIF-8-based materials for oil/water separation is also proposed.