论文部分内容阅读
将取自伊朗Yazd省Kooshk铅-锌尾矿坝的闪锌矿样进行生物浸出,并对比研究不同条件下的锌浸出率。Kooshk铅-锌尾矿坝含有3.64%锌、0.97%铅和24.18%铁。先将混合嗜温菌株、混合中度嗜热菌株进行摇瓶培养,然后在9K培养基中再次培养。在浸出闪锌矿的14 d内,在有菌株的情况下,闪锌矿的浸出率达90%,而没有菌株的情况下,只有44%的闪锌矿被浸出。实验结果表明,在有菌株浸出的前10 d,有没有9K培养液对锌的浸出率有明显影响,但随后其差别不明显,到最后趋于相同。锌浸出率的提高与细菌菌落数和Fe3+浓度的增加有关。中度嗜热菌浸取锌的动力学要求明显高于嗜温菌的,因此,在中度嗜热菌株存在的情况下,在低的氧化电位下闪锌矿优先于黄铁矿溶解而被浸出。
Bauxite samples taken from the Kooshk lead-zinc tailings dam in Yazd province, Iran, were bioleached and the zinc leaching rates under different conditions were compared. The Kooshk lead-zinc tailings dam contains 3.64% zinc, 0.97% lead and 24.18% iron. The mesophilic strains are mixed first, mixed moderate thermophilic strains are shake-flask cultured, and then cultured again in 9K medium. Within 14 days of leaching sphalerite, the sphalerite leaching rate was 90% in the presence of the strain, whereas only 44% of the sphalerite was leached in the absence of the strain. The experimental results showed that there was no significant effect of 9K medium on the leaching rate of zinc in the first 10 days after the strain was leached, but the difference was not obvious at the end of the first 10 days. The increase of zinc leaching rate is related to the increase of bacterial colony number and Fe3 + concentration. The kinetic requirements for leaching of zinc by moderate thermophilic bacteria are significantly higher than those of mesophilic bacteria, so that in the presence of moderate thermophilic strains, sphalerite preferentially dissolves in pyrite at low oxidation potentials Leaching.