عنوان مقاله [English]
نویسندگان [English]چکیده [English]
One of the main challenges in uranium bioleaching process is events related to improvement, acceleration and enhancement of the extraction. One of these is to provide a favorable environment and biological conditions for Acidithiobacillus ferrooxidans. Whereas, the nutrients of bacteria medium have a significant impact on the activity and growth of bacteria, in the present study, 2 selective culture mediums were used in uranium bioleaching process at pulp densities of 2.5 and 12.5 %. The mediums are containing usual 9k and enriched 9k medium with peptone and TSB (Tryptic Soy Broth). Uranium bioleaching process using selective 2 mediums with different pulp densities were performed under optimum conditions. The results indicated that the uranium extraction at 2.5% pulp density, using 9k-New medium and 9k medium, have carried out during 2 and 3 days, respectively. In addition, at 12.5 % pulp density, the total uranium in the ore was extracted during 3 and 7 days using 9k-New and 9k mediums, respectively. Eh variations showed that the Eh in the 9k-New medium in compared with 9k medium were increased 13-22%. According to the results of this study, it can be concluded that the uses of nutrients such as peptone and TSB have significant impact on the activity of bacteria and also speed of uranium extraction. So, the optimization of 9k medium using peptone and TSB recommended on the uranium bioleaching process.
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