摘要
Iron L-edge and sulfur K-edge X-ray absorption near edge structure（XANES） spectroscopy analysis of pyrite leached by extreme thermophilic Archaea strain Acidianus manzaensis（A.manzaensis） was carried out.Leaching experiments show that the oxidation of pyrite can be accelerated by A.manzaensis.Leaching results show that with the increase of leaching time,pH value in the leaching solution gradually decreases,redox potential increases rapidly from day 0 to day 3,and then increases slowly.The SEM results show that the pyrite surfaces are corroded gradually by A.manzaensis,and the XRD results show that the leaching residues contain new compositions of jarosite and elemental sulfur（S0）.The iron L-edge XANES spectroscopy analysis of pyrite during biooxidation indicates that pyrite is gradually converted to Fe（III）-containing species.The sulfur K-edge XANES spectroscopy analysis indicates that elemental sulfur is produced during bioleaching and maintains mass fractions of 3.2%-5.9%.Sodium thiosulfate was also detected from day 2 to day 4,indicating the existence of thiosulfate during biooxidation of pyrite.
基于同步辐射技术对Acidianus manzaensis（A.manzaensis）浸出黄铁矿过程中铁L边XANES和硫K边XANES进行光谱学分析。浸出实验表明,A.manzaensis能加速黄铁矿的氧化。随着浸出时间的增加,浸出液的pH值逐渐降低;氧化还原电位值在第0-3天快速增加,然后缓慢增加。SEM结果表明,黄铁矿表面被A.manzaensis逐渐腐蚀;XRD结果表明,浸出残渣包含新组分黄钾铁矾和单质硫。铁L边XANES光谱学分析表明,黄铁矿生物氧化过程中铁形态逐渐转变为含Fe（Ⅲ）物质。硫K边XANES光谱学分析表明,在黄铁矿生物浸出过程中产生元素硫且其质量比维持在3.2%-5.9%。硫代硫酸盐在第2-4天也被检测出来,这表明黄铁矿生物浸出过程中存在硫代硫酸盐。
基金
Project(51274257)supported by the National Natural Science Foundation of China
Project(U1232103)supported by the Joint Funds of National Natural Science Foundation of China and Large Scientific Facility Foundation of Chinese Academy of Sciences
Project(CX2014B092)supported by the Hunan Provincial Innovation Foundation For Postgraduate,China
Project(VR-12419)supported by Beijing Synchrotron Radiation Facility Public User Program,China
作者简介
Corresponding author： Jin-lan XIA; Tel： ＋86-731-8836944; E-mail： jlxia@csu.edu.cn
