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.
出处
《中国有色金属学会会刊：英文版》
EI
CSCD
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
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
biohydrometallurgy
bioleaching
anode oxidation
bacteria modification
powder microelectrode
chalcopyrite
kinetics
