Decontamination of Cr(Ⅵ) from water using sewage sludge-derived biochar: Role of environmentally persistent free radicals

作     者：Yuhan Zhu Jia Wei Jun Li Yuhan Zhu;Jia Wei;Jun Li

作者机构：Faculty of ArchitectureCivil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China 

出 版 物：《Chinese Journal of Chemical Engineering》 (中国化学工程学报（英文版）)

年 卷 期：2023年第56卷第4期

页      面：97-103页

核心收录：

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 

基　　金：supported by the Beijing Municipal Natural Science Foundation (8202007) the National Natural Science Foundation of China (52170148) 

主　　题：Sludge-derived biochar Environmentally persistent free radicals Chromium Removal Reduction 

摘      要：Biochar is a well-known material for pollutant removal owing to its low cost and rich surface functionality. A kind of highly active substance, called environmentally persistent free radicals(EPFRs), can be produced in the preparation process of biochar, playing an important role in the removal of *** this study, sludge-derived biochars(SBC_(120) and SBC_(270)) were prepared by the hydrothermal carbonization under two temperatures(120℃ and 270℃) to investigate their removal abilities of Cr(Ⅵ). The maximum removal amounts of Cr(Ⅵ) by SBC_(120) and SBC_(270) were 16.58 and 22.93 mg·g^(-1), respectively. It was further revealed that the appearance of Cr(Ⅲ), as a result of EPFRs on sludge-derived biochar(SBC) transferred electrons to Cr(Ⅵ) in neutral solutions. That is to say, oxygen-centered(O-centered) EPFRs on SBC_(120) and carbon-centered(C-centered) EPFRs on SBC_(270) all could be used as electron donors to Cr(Ⅵ) to make it become Cr(Ⅲ). This study not only provides a theoretical basis for the mechanism of pollutants removal by sludge-derived biochar but also offers a new perspective on the direct effect of EPFRs on pollutants.