Electrochemical behavior of chalcopyrite in presence of Thiobacillus ferrooxidans  

作　　者：李宏煦 邱冠周 胡岳华 苍大强 王淀佐 

机构地区：[1]School of Metallurgy and Ecology Engineering,University of Science and TechnologyBeijing [2]Key Laboratoryof Ecological and Recycling Metallurgy,Ministry of Education,Beijing 100083,China [3]School of Resources Processing and Bioengineering,Central South University

出　　处：《中国有色金属学会会刊：英文版》2006年第5期1240-1244,F0003,共6页Transactions of Nonferrous Metals Society of China

基　　金：Project(2004CB619205) supported by the National Basic Research Program of China; Project(50204001) supported by the National Natural Science Foundationof China

摘　　要：The chalcopyrite anode dissolution behavior in the presence or absence of bacteria in 9 K media using bacteria modified powder microelectrode at 30 ℃ was studied. It is found that during the anode dissolution, many intermediate transient reactions occur accompanying with the production of chalcocite and covellite at potential between - 0.075 V and - 0.025 V (vs SCE). At low scanning potentialbetween - 0.1 and - 0.250 V, the iron ion is released in ferrous form, but at the relative high potentialup to 0.7 V, it is the ferric one. The presence of Thiobacillus ferrooxidans makes peak current increase and the initial peak potential negatively move, hinting the decomposed oxidation reaction easily occurred and especially the iron ion released and ferrous oxidation reaction enhanced. The characteristic at potential between - 0.75 and - 0.5 V demonstrates the Thiobacillus ferrooxidans also contributes to the element sulfur formed on the oxidation surface and removed during anode process. The added ferric in the cell could enhance the dissolution reaction, while the increased acid under pH=2 might slightly hamper the process. The anode dissolution kinetics studies show that the presence of bacteria could decease corrosion potential from 0.238 V to 0.184 V and increase the corrosion current density from 1.632 14×10- A/cm2 to 2.374 11×10- A/cm2.The chalcopyrite anode dissolution behavior in the presence or absence of bacteria in 9 K media using bacteria modified powder microelectrode at 30 ℃ was studied. It is found that during the anode dissolution, many intermediate transient reactions occur accompanying with the production of chalcocite and covellite at potential between -0.075 V and -0.025 V （vs SCE）. At low scanning potential between -0.1 and -0.250 V, the iron ion is released in ferrous form, but at the relative high potential up to 0.7 V, it is the ferric one. The presence of Thiobacillus ferrooxidans makes peak current increase and the initial peak potential negatively move, hinting the decomposed oxidation reaction easily occurred and especially the iron ion released and ferrous oxidation reaction enhanced. The characteristic at potential between -0.75 and -0.5 V demonstrates the Thiobacillusferrooxidans also contributes to the element sulfur formed on the oxidation surface and removed during anode process. The added ferric in the cell could enhance the dissolution reaction, while the increased acid under pH=2 might slightly hamper the process. The anode dissolution kinetics studies show that the presence of bacteria could decease corrosion potential from 0.238 V to 0.184 V and increase the corrosion current deusity from 1.632 14×10^-8 A/cm^2 to 2.374 11×10^-7A/cm^2.

关 键 词：生物浸取 阳极氧化 细菌冶金 粉末微电极 黄铜矿 动力学 

分 类 号：TF18[冶金工程—冶金物理化学]