Effects of cobalt doping on the reactivity of hausmannite for As(Ⅲ)oxidation and As(Ⅴ)adsorption  

作　　者：Shuang Zhang Hui Li Zhongkuan Wu Jeffrey EPost Bruno Lanson Yurong Liu Biyun Hu Mingxia Wang Limei Zhang Mei Hong Fan Liu Hui Yin 

机构地区：[1]Key Laboratory of Arable Land Conservation(Middle and Lower Reaches of Yangtse River),Ministry of Agriculture and Rural affairs,College of Resources and Environment,Huazhong Agricultural University,Wuhan 430070,China [2]State Environmental Protection Key Laboratory of Soil Health and Green Remediation,Ministry of Ecology and Environment,Huazhong Agricultural University,Wuhan 430070,China [3]Department of Crop and Soil Sciences,North Carolina State University,Raleigh,North Carolina 27695,USA [4]College of Environment,Zhejiang University of Technology,Hangzhou 310014,China [5]Department of Mineral Sciences,NHB 119,Smithsonian Institution,Washington DC 20013-7012,USA [6]UniversitéGrenoble Alpes,Grenoble F-38000,France [7]CNRS,IRD,University of Savoy Mont Blanc,France [8]ISTerre,UniversitéGustave Eiffel,France [9]The Forestry Prospect Design Institute Of Hubei Province,Wuhan 430070,China [10]College of Grassland,Resources and Environment,Inner Mongolia Agricultural University,Hohhot 010018,China

出　　处：《Journal of Environmental Sciences》2022年第12期217-226,共10页环境科学学报（英文版）

基　　金：supported by the Key science and Technology Projects of Inner Mongolia Autonomous Region(No.2019ZD001);the National Natural Science Foundation of China(Nos.42077015,41771267 and 41877030);the National Key Research and Development Program of China(No.2016YFD0800403);the Fundamental Research Funds for the Central Universities(No.103-510320036)。

摘　　要：Hausmannite is a common low valence Mn oxide mineral,with a distorted spinel structure,in surficial sediments.Although natural Mn oxides often contain various impurities of transitional metals(TMs),few studies have addressed the effect and related mechanism of TM doping on the reactivity of hausmannite with metal pollutants.Here,the reactivity of cobalt(Co)doped hausmannite with aqueous As(Ⅲ)and As(Ⅴ)was studied.Co doping decreased the point of zero charge of hausmannite and its adsorption capacity for As(Ⅴ).Despite a reduction of the initial As(Ⅲ)oxidation rate,Co-doped hausmannite could effectively oxidize As(Ⅲ)to As(Ⅴ),followed by the adsorption and fixation of a large amount of As(Ⅴ)on the mineral surface.Arsenic K-edge EXAFS analysis of the samples after As(Ⅴ)adsorption and As(Ⅲ)oxidation revealed that only As(Ⅴ)was adsorbed on the mineral surface,with an average As-Mn distance of 3.25–3.30 A,indicating the formation of bidentate binuclear complexes.These results provide new insights into the interaction mechanism between TMs and low valence Mn oxides and their effect on the geochemical behaviors of metal pollutants.

关 键 词：Mn oxide HAUSMANNITE TRANSITION-METAL Cobalt Arsenate adsorption Arsenite oxidation 

分 类 号：X703[环境科学与工程—环境工程]