Abstract:

With the rapid development of industrialization, the problem of environmental pollution has become increasingly prominent. Oily sewage has attracted much attention because of its wide source, large processing capacity and difficult treatment. Due to its wide range of sources and complex components, it poses a great threat to the ecological environment and human health. For this kind of oily wastewater, the traditional treatment methods have the disadvantages of non-recyclable materials, high energy consumption and easy to cause secondary pollution. In view of the above problems, the development of efficient, convenient and environmentally friendly oil-water separation materials has become a key research direction in the field of oil-water separation. Inspired by the phenomenon of superwetting in nature, SA/TiO₂ composite porous materials were prepared by directional freezing/freeze-drying and ion crosslinking with sodium alginate as the substrate and titanium dioxide nanoparticles as heterogeneous reinforcements. The physical properties, chemical properties and microstructure of ST composite porous materials and their application in oil-water separation were analyzed. The addition of TiO₂ nanoparticles constructed a micro-nano rough structure on the surface of ST porous material, which can form a solid-water phase composite oil repellency. The contact area between oil and ST composite porous material was reduced. The oil-water separation efficiency of ST composite porous materials for different oils was more than 99.6%, and it was efficient and reusable in any environment, which had broad application prospects in the field of oil-water separation.

Key words: sodium alginate, titanium dioxide, porous materials, composites, oil-water separation

摘要：

伴随着工业化的快速发展，环境污染问题日渐突出，含油污水因其来源广、处理量大、处理困难而备受关注。由于其来源广泛、组分复杂，给生态环境和人体健康造成了很大的威胁。针对这类含油废水，传统的处理方法存在材料不可回收、耗能高、易造成二次污染等缺点。针对上述问题，开发高效、便捷且绿色环保的油水分离材料成为了油水分离领域的一个重点研究方向。受自然界超浸润现象的启发，以海藻酸钠（SA）为基材，加入二氧化钛（TiO₂）纳米颗粒为异质增强体，通过定向冷冻/冷冻干燥和离子交联的方法制备出了SA/TiO₂（ST）复合多孔材料。分析了ST复合多孔材料的物理特性、化学特性和微观形貌及其在油水分离中的应用效果。TiO₂纳米颗粒的添加，在ST多孔材料表面构筑出微纳米粗糙结构，可以形成固相-水相的复合拒油层；减小了油与ST复合多孔材料的接触面积。ST复合多孔材料对不同油类的油水分离效率达到99.6%以上，且在任何环境下都保持高效并可重复利用，在油水分离领域具有广阔的应用前景。

关键词: 海藻酸钠, 二氧化钛, 多孔材料, 复合材料, 油水分离