Study On The Synergistic Effect Of The Acid Iron/Sulfur Oxidize Bacteria In The Process Of Uranium Bioleaching

Bioleaching obtained the rapid development.Due to various different of characteristics and physiological and biochemical properties of bioleaching microbacteria,and bioleaching with mixed bacterial have complementary advantages.Therefore,the use of mixed bacterial leaching has become research hotspot in bioleaching.sulfur bacteria and iron bacteria are the dominant strains in bioleaching,It is the key to study the synergistic action of the ore in the bioleaching process.This article through the 9K liquid medium and Fe SO double anaerobic solid medium,Waksman liquid medium and iFeO double anaerobic solid medium enrichment,separation and purification of repeatedly crossed out two bacteria from the Jiangxi mine samples respectively,by limiting dilution for the calculation of the number of bacteria,the individual morphology was observed by scanning electron microscope,and then identify with 16 SrDNA,determine they are Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans.Two kinds of bacteria on the domestication of carbon silicon mudstone type uranium ore leaching solution adaptability,then the bacterial variables shake flask leaching test and two kinds of bacteria in different mixing ratio leaching test was designed。analysis of bacteria structure with fluorescence in situ hybridization,at last,depeng on the basis of the experimental data,select the appropriate access of bacteria,reaction temperature,reaction time and other experimental parameters of 721 two heap leaching scaling ore microbial test leaching treatment.Results are as follows:From carbonaceous siliceous pelitic rock type uranium enrichment and separation to two strains of bacteria,the results of physicochemical properties and scanning electron microscope identification and 16 S rDNA sequence show they are Acidthiobacillus ferrooxidans and Acidthiobacillus thiobacillus respectively.After acclimation, Stenotrophomonas acid Acidithiobacillus ferrooxidans can better adapt to the carbonaceous siliceous pelitic rock type uranium ore leaching solution,there is no decline in the ability for the oxidation of ferrous iron,still can oxidate 4g/L ferrous iron within 24 hours,addicted to acid Acidithiobacillus thiooxidans production ability of acid decreased slightly,the time pH value from 4 decrease to 1.7 needed by 2 days increased to 4 days.Select the 1mm screen of the ore,according to the ratio of solid to liquid 1:2.5,bacteria as the variable,at 30 degrees,the leaching of 150r/m shaker in 19 days,without bacteria,single Acidithiobacillus thiooxidans,single Acidithiobacillus ferrooxidans,Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans mixed those four group leaching system.The cumulative liquid leaching rate were arrive 25%,70.26%,80.50% and 82.43%, Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans mixed leaching can achieve the best effect of leaching;according to the Acidthiobacillus ferrooxidans and Acidthiobacillus thiobacillus respectively as the proportion of different proportions of 1:0.5,1:1,1:3,1:5,1:7 leaching results show that in the At.f:At.t is appropriate for the 1:3,but the leaching each test rate difference was about 70% in the leaching process, the composition of bacteria change structure,Acidithiobacillus ferrooxidans grown well in the leaching period,Acidithiobacillus thiooxidans is increasing,at the end of the experiment,has gradually become the dominant species.Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans mixed can achieve better effect,and can eliminate the mineral surface precipitates the dissolution.Soft fouling ore joined the exogenous iron with and without the addition of exogenous iron two groups in leaching solution of total iron content were increased 0.115g/L and 0.62g/L,pH from 2.35 and 2.18 decreased to 2.016 and 2.003,uranium leaching rate was 85.37% and 75.25% respectively;Induration scale ore joined the exogenous iron with and without the addition of exogenous iron two groups in leaching solution of total iron content were increased 0.136g/L and 0.49g/L,pH from 1.73 decreased to 1.469 and 143,uranium leaching rate were 83.21% and 76.77% respectively.In this paper the eosinophils of Acidithiobacillus ferrooxidans and addicted acid Acidithiobacillus thiooxidans mixed strains of two groups of uranium ore leaching study,from microbial quantity,activity and leaching results to verify the eosinophilic two bacteria in in bio leaching uranium process synergy,has an important practical significance for the leaching of minerals.