Ag^+对含砷金精矿生物浸出的影响  

Effect of Ag^+ on Bioleaching of Arsenic-bearing Gold Concentrate

作　　者：张明[1] 杨巧文[1] 张广积[2] 杨超[2] 

机构地区：[1]中国矿业大学(北京)化学工程系,北京100083 [2]中国科学院过程工程研究所,北京100190

出　　处：《过程工程学报》2012年第5期781-784,共4页The Chinese Journal of Process Engineering

基　　金：国家重点基础研究发展规划(973)基金资助项目(编号:2010CB630904);国家高技术研究发展计划(863)基金资助项目(编号:2012AA061503);国家自然科学基金资助项目(编号:51174185);北京市自然科学基金资助项目(编号:2112038)

摘　　要：研究了Ag+对含砷金精矿生物浸出的影响,测量了浸出液中铁、银、砷浓度及氧化还原电位(Eh)的变化,考察了Ag+对细菌密度的影响,并对浸渣进行了光谱表征.结果表明,Ag+对含砷金精矿的生物浸出有一定的促进作用且在高浓度Fe3+条件下催化作用明显;低Ag+浓度下含砷金精矿的生物浸出率提高约10%,但Ag+浓度过高将影响细菌生长,导致浸出速率下降.Ag+催化含砷金精矿生物浸出是Ag+取代矿物表面的砷并生成Ag2S,之后被Fe3+氧化分解,重新产生Ag+,从而加速矿物的氧化分解.The effect of Ag＋ on bioleaching of As-bearing gold concentrate was studied. The concentrations of Fe3＋, Ag＋ and As in the bioleaching solution were monitored during the leaching process. The effect of Ag＋ on the bacterial density was investigated and the leaching residue was characterized by XRD and SEM. The experimental results show that Ag＋ can enhance the bioleaching rate especially at the high concentration of Fe3 ＋, but the growth of bacteria was restrained under at higher concentration of Ag＋, leading to the decrease of leaching rate. Based on the leaching results and leaching residue analysis, the catalytic mechanism of Ag＋ was that the arsenic on the surface of concentrate was displaced by Ag＋, and Ages formed, which could be dissolved by Fe3＋, releasing Ag＋ again.

关 键 词：银离子 含砷金精矿 生物浸出 催化 

分 类 号：TF18[冶金工程—冶金物理化学]