Study On Enhance Bioleaching On Heavy Metal Of Copper Tailings By UV And Hydroxylamine Hydrochloride Respectively

Microbial leaching is favored with low energy consumption, short process flowand friendly environment, compared with traditional metallurgical technology.However, its low efficiency and long period hinders itself’s development andpromotion. For a long time, researchers have been studied high efficiency strains ofleaching ore and optimum condition. In this experiment, Acidithiobacillus ferrooxidanswas intensified by UV and hydroxylamine hydrochloride as primary factor respectivelyand LiCl as auxiliary factor. Then, Acidithiobacillus ferrooxidans was used forenrichment culture, domestication and for leaching of heavy metal from copper tailingssand. Comparing the leaching efficiency with one by Acidithiobacillus ferrooxidanswithout intensifying treatment, investigate the leaching rate higher or lower.Determinating16S rDNA sequence of Acidithiobacillus ferrooxidans with intensifyingtreatment and comparing the sequence with one from NCBI, study whether it leadsgene mutation to form the new species or not.In the experiment, copper tailings were grinded into85.34μm of mean averageparticle size, mainly including Si、Fe、Al、Ca and S besides Cd、Cu、Pb、Zn、Ti、Ni and As, high Fe and S content provided rich nutrients for Acidithiobacillusferrooxidans to develop.In the leaching experiment of copper tailings by Acidithiobacillus ferrooxidansintensified by UV and LiCl, strengthening conditions are1%LiCl、1%LiCl+0.5minUV、1%LiCl+1.0min UV、1%LiCl+1.5min UV、1%LiCl+2.0min UV. Setting twoleaching systems of the pulp density of5%and10%, adjusting pH to2.0andinoculating10%bacteria liquid in the early stage of leaching, maintaining systemtemperature30℃in the whole process of leaching. In the end of leaching experiment,the leaching rate of some heavy metals in some experimental groups improvesobviously compared to control group.In the leaching experiment of copper tailings by Acidithiobacillus ferrooxidansintensified by hydroxylamine hydrochloride and LiCl, strengthening conditions are1%LiCl、1%LiCl+0.25g HA、1%LiCl+0.50g HA、1%LiCl+0.75g HA、1%LiCl+1.00g HA. Setting two leaching systems of the pulp density of5%and10%,adjusting pH to2.0and inoculating10%bacteria liquid in the early stage of leaching,maintaining system temperature30℃in the whole process of leaching. In the end of leaching experiment, the leaching rate of some heavy metals in some experimentalgroups improves obviously compared to control group.The results of16S rDNA sequence determination of Acidithiobacillus ferrooxidansintensified by UV and hydroxylamine hydrochloride respectively showed there were nogene mutation to form the new species, it indicated UV and hydroxylaminehydrochloride only strengthen the leaching of heavy metal by Acidithiobacillusferrooxidans to some extent.