Researcher Ming Xue, and co-workers, from Jilin University, China, introduced micro/nanostructure into MOF membrane in order to improve water/oil separation efficiency. This work is published in Science China Materials.
Oil-water separation technologies in the past have included filtration, dissolved air flotation, centrifugation, oil skinners and adsorption, as well as other techniques. Such technologies are low efficiency and waste a lot of energy for their complex separation processes.
Xue’s team has supported the growing research on membrane separation as a promising and economical approach to tackle energy and environmental challenges. Some organic polymer membranes lose oil-water separation capacity at high temperature or exposure to various organic solvent and most inorganic membranes require significant preparation in time and resources.\
"We successfully constructed a ZIF-8-coated mesh membrane with excellent oil-water separation performance by simply immersing mesh in precursor solution under room temperature and atmospheric pressure", Professor Xue continued, "the membrane shows underwater superoleophobic properties, which is attributed to the micro and nanostructure on the surface of the ZIF-8-coated membrane."
Professor Xue explained, "the water phase imbibes into the micro and nano hierarchical structure of membrane surface, forming a barrier layer, which allows the water phase to pass through the membrane by its gravity quickly, and rejects the oil phase. This is the separation mechanism."