Acidithiobacillus ferrooxidans氧化分解毒砂的次生产物研究  

Secondary Minerals on Arsenopyrite Oxidized by Acidithiobacillus ferrooxidans

作　　者：朱婷婷[1] 陆现彩[1] 李娟[1] 陆建军[1] 王汝成[1] 徐兆文[1] 

机构地区：[1]内生金属矿床成矿机制研究国家重点实验室,南京大学地球科学与工程学院,江苏南京210093

出　　处：《矿物学报》2011年第4期683-691,共9页Acta Mineralogica Sinica

基　　金：国家重点基础研究发展计划(2007CB815603);国家自然科学基金(批准号:4093074210979018)

摘　　要：毒砂是常见的含砷硫化物矿物。在金属硫化物矿山环境中,含毒砂矿石和尾矿的风化会导致严重的重金属污染,在其风化过程中,微生物能够显著促进毒砂的氧化分解。本文实验研究了Acidithiobacillus ferrooxidans氧化分解毒砂矿物的现象,利用X射线衍射和扫描电子显微镜,分析了毒砂微生物氧化作用形成的次生矿物类型,发现毒砂表面存在As含量明显不同的2类次生产物,观察到黄钾铁矾、臭葱石、自然硫和施威特曼石等矿物;借助光电子能谱仪重点分析了微生物作用前后毒砂晶面的表面化学组成,基本查明了Fe、As和S三种元素的价态变化,初步探讨了毒砂表面次生矿物成因和As的化学态转化。Arsenopyrite is a common arsenic-bearing sulfide mineral.Weathering of arsenopyrite-bearing dumped ore or tailings in mines generally leads to serious heavy metal contamination.It is proved that microorganism can enhance the oxidation of arsenopyrite remarkably.Based on an experiment on Acidithiobacillus ferrooxidans-arsenopyrite interaction,secondary minerals formed in bio-weathering were investigated by using X-ray diffraction（XRD） and scanning electronic microcopy（SEM）.There were two types of sulfate precipitation with high and low As content,respectively.Secondary minerals,including jarosite,scorodite,natural sulfur and schwertmannite were identified.X-ray Photoelectron spectra（XPS） discloses the changes in chemical states of Fe,As and S of fresh and bio-oxidized arsenopyrite.The genesis of secondary minerals and the chemical state transformation of arsenic were discussed preliminarily.

关 键 词：毒砂 氧化亚铁硫杆菌 次生沉淀 SEM XPS 

分 类 号：P578.2[天文地球—矿物学] P579[天文地球—地质学]