Zhenhua Niu,Wenjia Luo,Weimin Liu,Qing Sun,Peng Mu,Jian Li
The efficient separation of emulsified oily wastewater is urgently needed and remains a worldwide challenge. However, the preparation of underwater superoleophobic materials still suffer from complicated process control, special equipment and expensive reagents, which further restricts the large-scale application of such materials. Herein, one-step constructing of underwater superoleophobic beds is introduced for highly efficient gravity-directed separation of various oil-in-water emulsions. Importantly, this study simplifies the fabrication process of underwater superoleophobic materials. It's worth noting that the strategy can achieve the effective separation of a range of oil-in-water emulsions by only requires simple accumulation of hydrophilic materials. More importantly, the underwater superoleophobic sandwich-structured beds still maintain the separation efficiency more than 99.2% after 10 cycles. In addition, this strategy is suitable for a variety of hydrophilic materials, which provides new perspectives for fabrication of novel oil-water emulsion-separating materials.
Pickering emulsion (PE) stabilized by semiconductors for photocatalysis applications has received growing endorsement over the last decade due to its high interfacial activity. However, since most semiconductors inherently possess a strongly hydrophilic or hydrophobic surface and are unable to stabilize PE microcapsules by themselves, pretreating the surface of semiconductor powder with foreign modifier was usually unavoidable and inconvenient before the PE construction. Even worse, the added modifier inevitably limited the contact between the semiconductor and the reactant during the photocatalysis process. Herein, an oil-in-water PE was successfully obtained in one step without pretratment of the semiconductor, where the dye-contained wastewater and insoluble organic matter acted as the water and oil phases, respectively, and the dye molecules in water could directly assist TiO 2 particles to become the stabilizer. The TiO 2 powder in the formed PE system exhibited markedly enhanced photoactivity for dye degradation over that in traditional non-emulsified systems, and the PE microcapsules could be easily recovered for reuse and withstand long-term irradiation without severe demulsification. This work not only highlights a convenient and promising approach to build Pickering emulsion as a novel photocatalytic system with extremely high efficiency and recyclability, but also provides a new way of thinking on how to simplify the PE construction to meet more requirement in future practical applications.
危险品化学品经营许可证（带存储）