中等嗜热菌浸出黄铜矿的温度影响规律及种群组成分析

摘要

在不同温度条件下进行浸出实验.研究结果表明:中等嗜热菌在12～55℃时可保持浸矿活性,其最适生长温度为45～50℃,温度达到60℃时初始阶段还保持一定活性,但几天后菌浓度逐渐降低,种群比例发生较大变化；克隆文库分析表明:45℃和60℃条件下浸矿细菌主要为Leptospirillum ferriphilum,Acidithiobacillus caldus,Sulfobacillus thermotolerans和Acidosphaera rubrifaciens,其中Leptospirillum ferriphilum菌所占比例较大,是浸矿过程中的优势菌种.60℃条件下浸出过程中还存在古生菌Ferroplasma cupricumulans,古生菌可以利用其他浸矿菌产生的有机物为能源生长.它们之间对浸出所起的作用是相辅相成的,可共同促进黄铜矿的溶解.%Bioleaching of chalcopyrite with moderate thermophilic bacteria was conducted at different temperatures. The results show that the moderate thermophiles can present bioleaching ability at 12-55 °C during leaching process. The optimum growth temperature is 45-50 °C. When the temperature reaches 60 °C, moderate thermophiles can maintain activity in the initial stage, but after a few days the bacteria concentration reduces gradually. 16S rDNA clone library reveals that the composition of moderate thermophiles at 45 °C and 60 °C are mainly Leptospirillum ferriphilum, Acidithiobacillus caldus, Sulfobacillus thermotolerans and Acidosphaera rubrifaciens. Leptospirillum ferriphilum is the dominant bacteria at the both temperatures, and archaea Fermplasma cupricumulans are found at 60 °C, which can use organic substances produced by other bacteria as energy source. It is suggested that these bacteria can supplement each other during bioleaching, thus facilitating the dissolution of chalcopyrite.