Incorporation of N-doped biochar into zero-valent iron for efficient reductive degradation of neonicotinoids:mechanism and performance  

作　　者：Xiangying Li Xiangyu Zhang Peng Zhang Xinhua Wang Hongwen Sun Yongyue Lu Le Jiao Chenglan Liu 

机构地区：[1]National Key Laboratory of Green Pesticide,South China Agricultural University,483#Wushan Road,Tianhe District,Guangzhou 510642,China [2]MOE Key Laboratory of Pollution Processes and Environmental Criteria,College of Environmental Science and Engineering,Nankai University,38#Tongyan Road,Haihe Education Park,Jinnan District,Tianjin 300350,China [3]Agro-Environmental Protection Institute,Ministry of Agriculture and Rural Affairs,31#Fukang Road,Nankai District,Tianjin 300191,China

出　　处：《Biochar》2023年第1期1343-1359,共17页生物炭（英文）

基　　金：National Natural Science Foundation of China(Nos.U21A20291,42377384);National Key R&D Program of China(No.2021YFD1000500);Major Research Plan of the Shandong Science Foundation(No.ZR2020ZD19).

摘　　要：The extensive use of neonicotinoids on food crops for pest management has resulted in substantial environmental contamination.It is imperative to develop an effective remediation material and technique as well as to determine the evolution pathways of products.Here,novel ball-milled nitrogen-doped biochar(NBC)-modified zero-valent iron(ZVI)composites(named MNBC-ZVI)were fabricated and applied to degrading neonicotinoids.Based on the characterization results,NBC incorporation introduced N-doped sites and new allying heterojunctions and achieved surface charge redistribution,rapid electron transfer,and higher hydrophobicity of ZVI particles.As a result,the interaction between ZVI particles and thiamethoxam(a typical neonicotinoid)was improved,and the adsorption-desorption and reductive degradation of thiamethoxam and·H generation steps were optimized.MNBC-ZVI could rapidly degrade 100%of 10 mg·L^(−1) thiamethoxam within 360 min,its reduction rate constant was 12.1-fold greater than that of pristine ZVI,and the electron efficiency increased from 29.7%to 57.8%.This improved reactivity and selectivity resulted from increased electron transfer,enhanced hydrophobicity,and reduced accumulation of iron mud.Moreover,the degradation of neonicotinoids occurred mainly via nitrate reduction and dichlorination,and toxicity tests with degradation intermediates revealed that neonicotinoids undergo rapid detoxification.Remarkably,MNBCZVI also presented favorable tolerance to various anions,humic acid,wastewater and contaminated soil,as well as high reusability.This work offers an efficient and economic biochar-ZVI remediation technology for the rapid degradation and detoxification of neonicotinoids,significantly contributes to knowledge on the relevant removal mechanism and further advances the synthesis of highly reactive and environmentally friendly materials.

关 键 词：Zero-valent iron(ZVI) Ball milling N-doped biochar Neonicotinoid degradation Electron efficiency 

分 类 号：X70[环境科学与工程—环境工程] O64[理学—物理化学]