KGM/CNF-不锈钢网油水分离材料的制备及其油水分离性能研究OA北大核心CSTPCD

With the rapid development of global economy, the increase of industrial oily wastewater discharge and the frequent leakage in the transportation of crude oil have seriously threatened the human living environment and global ecosystem. The work aims to achieve the separation of oil-water mixture with the prepared superhydrophilic/underwater superoleophobic functional materials on the surface of KGM/CNF-coated stainless steel mesh. Deposition of KGM/CNF on stainless steel mesh by the solution immersion method was used to construct the superhydrophilic/underwater superoleophobic surface. The KGM/CNF-stainless steel mesh oil-water separation material was prepared through deacetylation of KGM (Konjac Glucomannan, KGM) under heating conditions, reconstruction of KGM/CNF hydrogen bonding and rearrangement of CNF (Cellulose NanoFiber, CNF) on the surface of the material. The surface morphology, physical and chemical properties of the oil-water separation materials were characterized and analyzed by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and interface contact angle (ICA). The oil-water separation performance was investigated by infrared oil meter. The research results showed that KGM/CNF-stainless steel mesh used for oil-water separation material had excellent superhydrophilicity (WCA=0°) in air and superoleophobic performance (OCA≥151°) under water. Through the oil-water separation experiments, it was found that KGM/CNF-stainless steel mesh oil-water separation material could separate several kinds of oil-water mixtures efficiently under its own gravity at room temperature, such as soya bean oil and gasoline. The separation efficiency of the oil-water mixture reached 97.40％, and the separation flux was 1236.75 L/(m2·h). In this experiment, superhydrophilic underwater superoleophobic KGM/CNF-stainless steel mesh oil-water separation material is prepared by solution immersion method with konjac glucomannan and cellulose nanofibres as biomass materials and inorganic material as stainless steel mesh. KGM/CNF-stainless steel mesh oil-water separation material takes stainless steel mesh as the carrier, which overcomes the shortcoming of poor mechanical strength. It has excellent oil-water separation performance for five different oil-water mixtures. Through the data of nano-particle size analyzer, it can be obtained that most of the oil droplet particle sizes of the oil-water mixture and the filtrate after separation are distributed between 2-6 μm and 0.2-0.4 μm, which indicates that the KGM/CNF stainless steel mesh has a good ability to separate oil and water. The separation efficiency and flux do not decrease significantly under different oil-water mixtures with pH values of 1 to 13, indicating that the material has excellent corrosion resistance. Besides, because the material has hydrophilic and oleophobic properties, KGM/CNF-stainless steel mesh material shows good recyclability. The KGM/CNF stainless steel mesh oil-water separation material is repeatedly used to separate oil-water mixtures for 10 times. The material is rinsed with deionised water after each separation, and it still maintains high oil-water separation efficiency and separation flux, indicating the good reusability of KGM/CNF-stainless steel mesh material. This is beneficial to protecting the environment and reducing the cost of material preparation. Adopting KGM/CNF-stainless steel mesh materials in the oil-water separation is in a simple and green preparation process, and the prepared materials are cheap and easy to obtain. Therefore, it has a high potential application prospect for the separation of oil-water system.