PEG-2000液氮保藏混合浸矿菌对黄铜矿生物浸出的影响

Comparison of bioleaching of chalcopyrite concentrates with mixed culture after cryopreservation with PEG-2000 in liquid nitrogen

首先,富集到具有浸矿能力的混合培养物,然后,以PEG-2000作为保护剂,对混合培养物液氮冷冻保藏6个月和12个月,对其保藏前、后黄铜矿的浸出能力、活性和多样性进行比较。结果表明,当用原始培养物浸出黄铜矿时,20天内铜的浸出率为95.7%。冷冻保藏6个月后,混合培养物的铜浸出率在25天内为94.9%,保藏12个月后,在35天内为93.6%。保藏6个月和12个月后,混合菌种的活性分别达到87%和41%。此外,对原始培养物进行生态学分析,鉴定得到Acidithiobacillus ferrooxidans,Acidithiobacillus caldus,Sulfobacillus thermotolerans和Pseudomonas aeruginosa。冷冻保藏12个月后,混合培养物的群落组成发生了变化,但优势菌群依然存在。

A mixed culture of bioleaching microorganisms was enriched.Then the mixed culture was preserved by liquid nitrogen cryopreservation for 6 months and 12 months,respectively,using PEG-2000 as the protective agent.The chalcopyrite leaching ability,activity and diversity of the mixed culture before and after preservation were compared.The results showed that the copper extraction rate was 95.7%in chalcopyrite bioleaching within 20 d by the original culture.After cryopreservation for 6 months and 12 months,the copper extraction rate of the mixed culture was 94.9%within 25 d and 93.6%within 35 d,respectively.The cell viability achieved 87%and 41%after being preserved for 6 months and 12 months,respectively.Furthermore,the ecology analysis identified Acidithiobacillus ferrooxidans,Acidithiobacillus caldus,Sulfobacillus thermotolerans and Pseudomonas aeruginosa in the original mixed culture.After cryopreservation for 12 months,the composition of community changed,but the predominant microorganisms still existed.