Fe(Ⅱ)浓度及时序性对硫还原作用去除水体中Sb或As的影响  

Impact of Iron(Ⅱ)Concentration and Sequential Addition of Metal(loids)on the Removal of Aqueous Antimony and Arsenic Through Microbial Sulfate Reduction

作　　者：柳凤娟 张国平[2] 罗绪强 余乐正 张其芳 LIU Fengjuan;ZHANG Guoping;LUO Xuqiang;YU Lezheng;ZHANG Qifang(School of Geography and Resources,Guizhou Education University,Guiyang 550018,China;State Key Laboratory of Environmental Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550081,China;School of Chemistry and Materials Science,Guizhou Education University,Guiyang 550018,China)

机构地区：[1]贵州师范学院地理与资源学院,贵阳550018 [2]中国科学院地球化学研究所环境地球化学国家重点实验室,贵阳550081 [3]贵州师范学院化学与材料学院,贵阳550018

出　　处：《地球与环境》2024年第5期631-640,共10页Earth and Environment

基　　金：国家自然科学基金项目(41563007);贵州省基础研究计划(黔科合基础-ZK[2022]一般330)。

摘　　要：通过批处理实验模拟的方法在微生物硫还原反应器中按照不同时序加入不同浓度的Fe^(2+)(初始浓度设为10、20、50、100、200、500mg/L)及不同形态的锑(Sb)或砷(As)(Sb(Ⅴ)+As(Ⅴ)或Sb(Ⅲ)+As(Ⅲ),初始浓度均为5mg/L),分析Sb或As加入后0.5h及7d内基质pH、氧化还原电位值(Eh)、总碱度、SO_(4)^(2-)、硫化物等理化指标的变化以及Fe、Sb或As含量的变化,以明确Fe^(2+)浓度及(类)金属加入的时序性对微生物硫还原作用去除水体中Sb或As效率及机理的影响。结果表明,相较于元素的加入时序,Fe^(2+)浓度对处理效果的影响更为显著,低浓度(≤20mg/L)对As的去除没有明显的促进作用,较高浓度(≥50mg/L)则能显著提高As的去除效率;而所有处理中Sb的去除率均达95%以上,使得时序性及Fe^(2+)浓度对于Sb去除的影响较难界定。在微生物硫还原作用处理含有Sb或As的废水时,应考虑添加Fe^(2+)来提高去除效率,而在通过强化微生物硫还原作用治理Sb或As污染的沉积物或壤土时,也需把含铁矿物的环境行为考虑在内,以取得更为显著的治理效果。Different Fe^(2+)concentrations(10,20,50,100,200 and 500 mg/L),antimony(Sb),and arsenic(As)species(i.e.Sb(Ⅴ)+As(Ⅴ)and Sb(Ⅱ)+As(Ⅲ),5 mg/L)were introduced to batch experiments of microbial sulfate reduction at different intervals.The changes in physicochemical parameters such as pH,redox potential(Eh),total alkalinity,SO_(4)^(2-)sulfides,and variations in Fe,Sb,or As concentrations were analyzed at O.5h and on the 7^(th) day afer Sb and As addition toelucidatetheffects of Fe^(2+)concentrations and the adding sequenceof Fe^(2+),Sb and As on the efficiency and mechanisms of microbial sulfate reduction to remove aqueous Sb and As.Results indicated that compared to the adding sequence,Fe^(2+)concentration had a more significant impact on the removal fficiency.Lower Fe^(2+)concentrations(<20 mg/L)did not promote As removal.In comparison,higher Fe^(2+) concentrations(≥50 mg/L)significantly improved As removal efficiency.Antimony removal exceeded 95%for all treatments,so the effects of adding sequences and Fe^(2+)concentrations on Sb removal were challenging to delineate.When treating Sb and As containing wastewater through microbial sulfate reduction,the addition of Fe^(2+)should be considered to enhance removal efficiency.Similarly,the environmental behavior of Fe-bearing minerals needs to be better considered when treating Sb-and As-contaminated sediments or soils by enhanced microbial sulfur reduction to achieve more significant remediation results.

关 键 词：硫酸盐还原菌 SB AS Fe(Ⅱ) 

分 类 号：X703.1[环境科学与工程—环境工程]