Construction Of Superhydrophilic-superoleophobic Membrane Based On Resin Enabling High-efficient And Ultra-fast Oil-water Separation

In industrial production and daily life,a large amount of oily wastewater will be generated,and the random discharge will cause unpredictable harm to the environment in which we live.High-efficiency,low-energy oil-water separation technology is an important means to avoid the discharge of oily wastewater and effectively recycle it.Traditional separation methods have the disadvantages of high cost and low efficiency.Membrane separation technology has received widespread attention from scholars at home and abroad in oil-water separation because of its low manufacturing cost and simple application process,such as superhydrophobic superoleophilic membrane and superhydrophilic superoleophobic membrane.At present,the commonly used superhydrophobic superoleophilic membrane is suitable for oil-water separation system with heavy oil and light water.However,most oils are less dense than water,so the application of this oil-water separation membrane is severely limited.The development of superhydrophilic superoleophobic membrane can effectively solve this problem,and how to prepare a superhydrophilic superoleophobic membrane with high throughput and high separation efficiency has become an important topic in the current application research.In this paper,superoleophobic superhydrophilic films were prepared using hydrophilic resins,and their application performance in efficient and high-throughput oil-water separation was explored.The influence of cross-linking agent and material surface treatment on the hydrophilicity,oleophobicity and application performance of polyacrylic resin was explored.The results show that the underwater oil contact angle of the separation membrane constructed with polyvinyl alcohol as the crosslinking agent and ammonia gas as the surface treatment agent is 160°,the rolling angle is 2°,and the contact angle to water droplets is close to 0°.Shows excellent super-hydrophilic and super-oleophobic functions.An inverted oil-water separation device was constructed based on the super-hydrophilic and super-oleophobic separation membrane,and the separation performance of the device for kerosene-water,soybean oil-water,rapeseed oil-water and hexadecane-water mixed systems was studied and evaluated.The results show that the separation flux for the kerosene-water mixed system is as high as 11740 L m^-2h^-1,the separation efficiency reaches 99.96%,and it can be separated continuously for more than 200 times;For the soybean oil-water mixed system,the separation flux reaches 11570 L m^-2h^-1,the separation efficiency reaches 99.96%,and the separation can be continuous for more than 200 times;For the rapeseed oil-water mixed system,the separation flux can reach 11480 L m^-2h^-1,the separation efficiency can reach99.96%,and it can be separated continuously for more than 200 times;The separation flux of the hexadecane-water mixed system reaches 12920 L m^-2h^-1,the separation efficiency reaches 99.96%,and the separation can be performed continuously for more than 200 times.The above research results show that we have successfully constructed a superhydrophilic resin-based superoleophobic separation membrane,which has the characteristics of high flux and high separation efficiency for common oil-water systems,and has broad and far-reaching application prospects in the field of oil-water separation.