嗜酸氧化亚铁硫杆菌的耐砷驯化与浸矿能力

Domestication for arsenic-tolerant ability and bioleaching of Acidithiobacillus ferrooxidans

为提高嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans,A.f)浸出砷金精矿过程中的氧化活性和耐砷能力,采用连续转接驯化法对分离纯化得到的A.f菌株NSJ209进行耐砷驯化,并考察原始菌和驯化菌对As(Ⅲ)和As(Ⅴ)的耐受能力。研究结果表明:连续转接驯化可以提高NSJ209的氧化活性和对砷的耐受性,驯化菌在含3 g/L As(Ⅲ)的9K培养基中,84 h内Fe2+的平均氧化速率比驯化前提高了3.53倍,对As(Ⅲ)的耐受性从驯化前的4 g/L提高到6 g/L,对As(Ⅴ)的耐受性从驯化前的8 g/L提高到12 g/L。在温度30℃、pH 2.0、矿浆质量分数6%的条件下对砷金精矿进行浸出试验,浸出10 d,驯化菌对砷的浸出率达到91.6%,比原始菌提高了38.01%。

To raise the oxidative activity and arsenic-tolerant ability of Acidithiobacillusferrooxidans in the leaching of arsenic-containing gold concentrate, continuous transfer domestication was put forward to obtain strains of Acidithiobacillus ferroxidans which can tolerante high concentrations Arsenic, and the tolerant ability to As（Ⅲ） and As（Ⅴ） of the adapted bacteria and unadapted bacteria were studied. The results show that the continuous transfer domestication can raise the oxidation activity and arsenic-tolerant ability of NSJ209 strains. And in 84 h, the oxidation of Fe^2＋ is improved by nearly 3.53 times than unadapted bacteria in 9K culture medium containing 3 g/L As（Ⅲ）. Compared with the unadapted bacteria, the tolerant ability to As（Ⅲ） is increased from 4 g/L to 6 g/L, and the tolerant ability to As（Ⅴ）） is increased from 8 g/L to 12 g/L. Under the conditions of 30 ℃, pH 2.0, pulp density 6%, after 10 d leaching, the arsenic leaching rate of the adapted bacteria is 91.6%, which is 38.01% higher than that of unadapted bacteria.