Tu Wenjun, Cai Weiquan
Guangzhou Higher Education Mega Center, School of Chemistry and Chemical Engineering, Guangzhou University, 230 Wai Huan Xi Road, Guangzhou 510006, China.
Toxics. 2024 Jun 21;12(7):447. doi: 10.3390/toxics12070447.
Large volumes of wastewater containing toxic contaminants (e.g., heavy metal ions, organic dyes, etc.) are produced from industrial processes including electroplating, mining, petroleum exploitation, metal smelting, etc., and proper treatment prior to their discharge is mandatory in order to alleviate the impacts on aquatic ecosystems. Adsorption is one of the most effective and practical methods for removing toxic substances from wastewater due to its simplicity, flexibility, and economics. Recently, hierarchical oxide composites with diverse morphologies at the micro/nanometer scale, and the combination advantages of oxides and composite components have been received wide concern in the field of adsorption due to their multi-level structures, easy functionalization characteristic resulting in their large transport passages, high surface areas, full exposure of active sites, and good stability. This review summarizes the recent progress on their typical preparation methods, mainly including the hydrothermal/solvothermal method, coprecipitation method, template method, polymerization method, etc., in the field of selective adsorption and competitive adsorption of hazardous substances from wastewater. Their formation processes and different selective adsorption mechanisms, mainly including molecular/ion imprinting technology, surface charge effect, hard-soft acid-base theory, synergistic effect, and special functionalization, were critically reviewed. The key to hierarchical oxide composites research in the future is the development of facile, repeatable, efficient, and scale preparation methods and their dynamic adsorption with excellent cyclic regeneration adsorption performance instead of static adsorption for actual wastewater. This review is beneficial to broaden a new horizon for rational design and preparation of hierarchical oxide materials with selective adsorption of hazardous substances for wastewater treatment.
包括电镀、采矿、石油开采、金属冶炼等在内的工业生产过程会产生大量含有有毒污染物（如重金属离子、有机染料等）的废水，为减轻对水生生态系统的影响，在排放前进行适当处理是必不可少的。吸附法因其简单、灵活和经济，是从废水中去除有毒物质最有效和实用的方法之一。近年来，具有微/纳米尺度多种形态的分级氧化物复合材料，以及氧化物与复合组分的组合优势，因其多级结构、易于功能化的特点，从而具有较大的传输通道、高比表面积、活性位点充分暴露和良好的稳定性，在吸附领域受到广泛关注。本文综述了其典型制备方法的最新进展，主要包括水热/溶剂热法、共沉淀法、模板法、聚合法等，以及在从废水中选择性吸附和竞争性吸附有害物质领域的研究进展。对其形成过程和不同的选择性吸附机制，主要包括分子/离子印迹技术、表面电荷效应、软硬酸碱理论、协同效应和特殊功能化等进行了批判性综述。未来分级氧化物复合材料研究的关键在于开发简便、可重复、高效和规模化的制备方法，以及具有优异循环再生吸附性能的动态吸附，而非针对实际废水的静态吸附。本文综述有助于拓宽合理设计和制备具有选择性吸附有害物质性能的分级氧化物材料用于废水处理的新视野。
