Shewanella oneidensis MR-1还原铁帽过程中的矿物相转变和重金属的释放  

Reduction of Gossan by Shewanella Oneidensis MR-1 and Its Influences on the Release of Heavy Metals

作　　者：张蕊 陆现彩[1] 刘欢 李娟[1] 向婉丽 陈笑夜[1] 

机构地区：[1]表生地球化学教育部重点实验室,南京大学地球科学与工程学院,南京210023

出　　处：《矿物岩石地球化学通报》2015年第2期316-322,共7页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家重点基础研究发展计划项目(2014CB846004);国家自然科学基金项目(41272056,40930742)

摘　　要：本文以江西武山吴家山铜矿铁帽为研究对象、以合成针铁矿为对照,研究异化铁还原菌Shewanella oneidensis MR-1还原铁帽过程中的矿物物相变化和重金属的释放。使用邻菲啰呤法、ICP-OES、SEM、TEM、XRD和FTIR等分析方法,系统表征了实验体系中矿物物相和溶液化学组成的变化。Fe的释放趋势表明MR-1菌株还原了铁帽中的高铁矿物,并导致铁帽中重金属元素的释放。由于菌体和次生矿物的影响,不同重金属元素的活动性存在差异,Mn和As多以次生矿物形式再次沉淀,而菌体对Zn和Cu、Pb的吸附能力较强。同时发现死菌组中亦有高铁矿物被还原的现象,可能与有机质的还原有关。The gossan of Wujiashan, Wushan, Jingxi, and the synthesized goethite were employed to react with a well- known dissimilatory iron reducing bacteria, Shewanella oneidensis MR-1, to disclose the geochemical behavior of heavy metals during the reduction process and to further understand the mechanism of microbial reduction of trivalence iron minerals. The changes in solution chemistry and mineral components were investigated using various methods of o-phenanthroline method, ICO-OES, SEM, TEM, XRD, FTIR and so on. The release of Fe^2＋ and Fe^3＋ ions into the solution revealed that the ferric minerals were reduced and various heavy metals were released. Due to the influences of secondary minerals and bacteria cells, different heavy metals exhibited various behaviors. The released manganese and arsenic were re-fixed into secondary minerals, while zinc, copper and lead were adsorbed onto the surface of bacteria cells. Meanwhile, the reduction of ferric minerals was detected in the group inoculated with killed ceils, which indicated that the organic matter also can promote the reducing of ferric minerals.

关 键 词：异化铁还原 重金属迁移 铁帽 SHEWANELLA oneidensis MR-1 

分 类 号：P593[天文地球—地球化学]