Heavy metal pollution in water has always been an environmental issue of global concern. Water treatment residual (WTR), generated during drinking water treatment processes, has proven to be a potentially cost-effective adsorbent for heavy metals. However, the application of raw WTR is restricted due to its defects. The purpose of this review is to summarize representative research on modified WTR, elucidating the impact of various modification methods on the physicochemical properties of WTR, which is rare in previous review articles. Furthermore, the review discusses the factors influencing the adsorption of WTR and the competitive adsorption among heavy metals. The main results indicate that methods such as heat treatment, acid activation, and development of composites have been successfully applied in modifying WTR, demonstrating the importance of optimizing the adsorption of WTR by altering its properties. The adsorption capacity of WTR is regulated by multiple factors, and the competitive adsorption capacity of heavy metals is proportional to ionic radius and electronegativity. Studying adsorption under conditions of multi-metal coexistence is crucial for the application of WTR in real aquatic environments. This review aims to provide valuable information for remediating heavy metal pollution and optimizing the utilization of WTR to promote global sustainable development.

中文翻译：

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改性水处理残渣用作去除水中重金属的吸附剂：综述


水中的重金属污染一直是全球关注的环境问题。饮用水处理过程中产生的水处理残渣 （WTR） 已被证明是一种可能具有成本效益的重金属吸附剂。然而，由于其缺陷，原始 WTR 的应用受到限制。本文旨在总结改性 WTR 的代表性研究，阐明各种改性方法对 WTR 理化性质的影响，这在以往的综述文章中是罕见的。此外，本文还讨论了影响 WTR 吸附的因素以及对重金属的竞争吸附。主要结果表明，热处理、酸活化和复合材料开发等方法已成功应用于 WTR 改性，证明了通过改变 WTR 性能来优化 WTR 吸附的重要性。WTR 的吸附能力受多种因素调节，对重金属的竞争吸附能力与离子半径和电负性成正比。研究多金属共存条件下的吸附对于 WTR 在实际水生环境中的应用至关重要。本文旨在为重金属污染整治和优化 WTR 利用以促进全球可持续发展提供有价值的信息。