| Title |
A Preliminary Study on the Metal Dissolution from Mine Tailings using Thiobacillus ferrooxidans |
| Authors |
강선홍 ; 최상일 ( Seon Hong Kang ; Sang Il Choi ) |
| Abstract |
Zinc metal and zinc sulfide were recovered by oxidative dissolution using Thiobacillus ferrooxidans, which is aerobic, autotrophic, and acidophilic bacteria. Thiobacillus ferrooxidans derive energy from oxidation of ferrous iron and elemental sulfur using molecular oxygen as an electron acceptor. From the 10,000㎎/L of initial zinc concentration, 97% solubilization of zinc metal was obtained from coarse FeS₂ due to microbial action. Also, about 70% metal solubilization occurred with fine sized materials in 58days. The general trend observed for the ZnS systems was a decrease in pH with time. The pH drop is an indication that microorganisms are acclimating and producing acidic by-products. The iron oxidation state changes due to substrate containing coarse particle size FeS₂ was shown. The sharp drop of ratio of Fe(II)/Fe(Total) and sharp increase of ratio of Fe(III)/Fe(Total) was observed in 20days after inoculation. Thus, microbial activity began more rapidly for the coarse particle size substrate than for the fine FeS₂. |