Purpose of Review

The biochar-supported zero valent iron (ZVI-BC) can effectively prevent oxidation and agglomeration of ZVI, and improve the utilization rate of ZVI. Recent reviews of ZVI-BC mainly focus on the preparation methods, characterization techniques, and reaction mechanism with pollutants. Since the structural characteristics of biochar have a great impact on Fe⁰ loading, a comprehensive review of the structural characteristics of biochar is needed to explain its influence on ZVI formation during preparation. And in application of ZVI-BC, the environmental effects on organisms need to be considered. This review of recent research results provides a perspective for understanding the structural characteristics, preparation factors, and ecotoxicity of ZVI-BC.

Recent Findings

The adsorption capacity of ZVI-BC prepared by conventional methods still needs to be improved. The surface-area-normalized reaction rate constant (k_SA) of ZVI-BC can be increased to about 180 times by surface modification, adding a stabilizer, element doping, and other modification methods. Recent research on ecotoxicity has shown mostly positive effects of ZVI-BC on microorganisms, animals, and plants during environmental remediation.

Summary

This work reviews the effect of biochar as a support matrix on Fe⁰ production. The pollutant removal performance is summarized considering the elemental composition, phase components, and surface chemical properties. Also, we discuss the effect of ZVI-BC preparation on contaminant removal and propose methods to optimize the performance of ZVI-BC. The k_SA was used to conduct a meta-analysis of kinetic data to illustrate the properties of ZVI-BC. In addition, we evaluate the ecotoxicity of using ZVI-BC in environmental remediation.

Graphical Abstract

中文翻译：

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生物炭负载零价铁（ZVI-BC）的结构特征、结构-应用关系及环境应用研究进展

审查目的

生物炭负载零价铁（ZVI-BC）可以有效防止ZVI氧化和团聚，提高ZVI的利用率。ZVI-BC 最近的综述主要集中在制备方法、表征技术和与污染物的反应机理上。由于生物炭的结构特征对 Fe ⁰负载量有很大影响，因此需要全面审查生物炭的结构特征以解释其在制备过程中对 ZVI 形成的影响。并且在ZVI-BC的应用中，需要考虑环境对生物体的影响。这篇对近期研究成果的综述为理解 ZVI-BC 的结构特征、制备因素和生态毒性提供了一个视角。

最近的发现

常规方法制备的ZVI-BC的吸附能力仍有待提高。通过表面改性、添加稳定剂、元素掺杂等改性方法，可以将ZVI-BC的表面积归一化反应速率常数（ k _{SA ）提高到180倍左右。}最近关于生态毒性的研究表明，在环境修复过程中，ZVI-BC 对微生物、动物和植物产生了大部分积极影响。

概括

^{这项工作回顾了生物炭作为支持基质对 Fe 0}生产的影响。考虑到元素组成、相组分和表面化学性质，总结了污染物去除性能。此外，我们还讨论了 ZVI-BC 制备对污染物去除的影响，并提出了优化 ZVI-BC 性能的方法。k _SA用于对动力学数据进行荟萃分析，以说明 ZVI-BC 的特性。此外，我们评估了在环境修复中使用 ZVI-BC 的生态毒性。

图形概要