超疏水/超亲油 RGO/TiO $ _{2} $@MS 海绵的制备及油水分离性能

文章采用浸渍法制备一种表面柔软的超疏水/超亲油还原氧化石墨烯(reduced graphene oxide, RGO)/二氧化钛 $ \left(\mathrm{TiO}_{2}\right) $三聚氰胺海绵(melamine sponge, MS)(RGO/TiO $ _{2} $@MS)，可实现油水的高性能和高效率分离。RGO/TiO $ _{2} $纳米复合材料与MS的结合赋予两亲性MS超疏水和超亲油性能(水接触角152°、油接触角0°)，实现三维MS材料有效、快速的油水分离，其油水分离效率高于99.5%，有良好的机械稳定性、化学稳定性和持久的抗污染能力。此外，在使用RGO/TiO $ _{2} $@MS三维材料对以正已烷为模型油的油水乳液进行油水分离中，重复吸油—挤压—吸油步骤100次后，RGO/TiO $ _{2} $@MS三维材料仍然具有优异的油水选择性，且分离效率仍可达95%以上，因此该材料具备可循环利用的优点。研究结果表明，RGO/TiO $ _{2} $@MS是一种技术简单、可以快速生产、可重复性高的超疏水/超亲油三维新型油水分离材料，同时具备经济性和环境友好性，可在实际工业生产中推广应用。

A three-dimensional(3D) mesh material of super-hydrophobic/super-lipophilic reduced graphene oxide/titanium dioxide melamine sponge $ \left(\mathrm{RGO}/\mathrm{TiO}_{2}@\mathrm{MS}\right) $ with soft surface was prepared by impregnation method, which can achieve high sorption selectivity and high sorption efficiency for oil-water separation. The combination of $ RGO/TiO_{2} $ nanocomposites and MS endows amphiphilic MS with super-hydrophobic and super-lipophilic properties (water contact angle $ 152^{\circ} $, oil contact angle $ 0^{\circ} $), which enables the 3D MS material to effectively and rapidly separate oil from water. The separation efficiency is higher than 99.5%, and it also has good mechanical stability, chemical stability and long-lasting anti-pollution ability. In the n-hexane oil-water emulsion separation test, 3D $ RGO/TiO_{2}@MS $ material showed excellent oil-water selectivity, and the separation efficiency could still reach more than 95% after 100 times of repeated oil sorption-extrusion-oil sorption, demonstrating that the material is recyclable. The results show that $ RGO/TiO_{2}@MS $ is a new type of superhydrophobic/super-lipophilic 3D oil-water separation material with simple technology, ease of fabrication and high repeatability, which is economical and environmentally friendly. These features manifest its attractive potential application in water purification.