Abstract: In order to solve problems that the mesophilic bacteria such as Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum have slow growth and reproduction and have a low oxidation rate of Fe²⁺ as oxidant agent at low temperature in high acidity leaching-finished solution,such issues as the growth characteristics of acidithiobacillus ferrivorans and its acid tolerance domestication and immobilization culture were preliminarily studied,combining with the actual production situation of in-situ leaching uranium in Xinjiang.The experimental result indicated that the inoculum quantity of this bacterium was controlled at about 10%;When the initial concentration of Fe²⁺ was 0.3～0.5 g/L,the bacteria still maintained a fast rate of oxidation with Fe²⁺;At the temperature of 5～25 ℃,Fe²⁺oxidation rate of Acidithiobacillus ferrivoran was higher than that of Acidithiobacillus ferrooxidans,namely Acidithiobacillus ferrivorans was more suitable for leaching solution at low temperature environment;Acidithiobacillus ferrivorans could keep better oxidation activity in nutrient fluid after domesticated in acid condition (pH=0.31);A thicker biofilm could be observed in the SEM images of the Bio-ceramic,and the Fe²⁺ oxidation rate of synergistic interaction between immobilized bacteria and dissociative bacteria was about 3.4 times as much as that of dissociative bacteria.

Key words: Acidithiobacillus ferrivorans, Domestication of acid-resistance, Immobilization culture, Bio-ceramic, Biofilm