Harbin Institute of Technology develops a new super-hydrophilic membrane to break through the bottleneck of secondary pollution!

Science and Technology Daily (Reporter Li Liyun, Correspondent Zhang Yuqin) On September 10, the reporter learned from Harbin Institute of Technology that the team of Academician Ma Jun from the Sino-European Membrane Technology Research Institute of the School of Marine Science and Technology at the Weihai Campus of the university has obtained a biodegradable super-hydrophilic nanofiber oil-water separation membrane through electrospinning technology, breaking through the bottleneck of secondary pollution after the traditional polymer separation membrane is discarded . The results were recently published in the journal Science Advances.

Industrial oily wastewater discharge poses a major threat to ecosystems and human health, and seriously damages the global water-food-energy chain. At present, oil-water separation mainly relies on super-hydrophilic organic polymer materials to form a hydration layer on the surface of the material to prevent oil from passing through. However, in existing oil-water separation membranes, super-hydrophilic membrane materials are mostly derived from fossil resources, and membrane waste is often disposed of by landfill or incineration. Improper management will produce secondary pollution such as microplastics, which is not conducive to the sustainable development of the ecological environment.

In this study, the team used the strategy of electrospinning of biodegradable super-hydrophilic membranes to prepare environmentally friendly super-hydrophilic polylactic acid nanofiber membranes. "This strategy allows polylactic acid and polyethylene oxide hydrogel to form a cross-linked structure. By controlling the electrospinning parameters and designing an asymmetric structure, a high permeability flux, high separation efficiency and biodegradable super-hydrophilic polylactic acid nanofiber membrane is obtained. The separation efficiency of this membrane exceeds 99.6%." Cheng Xiquan, the first author of the paper and a distinguished professor at the School of Marine Science and Technology, Weihai Campus of Harbin Institute of Technology, told reporters that this kind of membrane has stable performance under the conditions of use and can be biodegraded within 1 week after being treated with proteinase K, providing a new way for green and low-carbon development for the preparation of polymer oil-water separation membranes.

It is reported that the preparation strategy of this membrane provides a universal hydrophilic modification method for the new generation of high-performance polymer matrix membranes, and at the same time provides forward-looking technical support for the efficient and rapid separation and purification of oily wastewater.