Mousavi S M, Yaghmaei S, Vossoughi M, Roostaazad R, Jafari A, Ebrahimi M, Chabok O Habibollahnia, Turunen I
Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran.
Bioresour Technol. 2008 May;99(8):2840-5. doi: 10.1016/j.biortech.2007.06.009. Epub 2007 Aug 14.
In this study the effects of initial concentration of Fe(II) and Fe(III) ions as well as initial pH on the bioleaching of a low-grade sphalerite ore in a leaching column over a period of 120 days with and without bacteria were investigated. Four different modifications of medium were used as column feed solutions to investigate the effects of initial concentration of Fe(II) and Fe(III) ions on zinc extraction. The experiments were carried out using a bench-scale, column leaching reactor, which was inoculated with mesophilic iron oxidizing bacteria, Acidithiobacillus ferrooxidans, initially isolated from the Sarcheshmeh chalcopyrite concentrate (Kerman, Iran). The effluent solutions were periodically analyzed for Zn, total Fe, Fe(II) and Fe(III) concentrations as well as pH values. Bacterial population was measured in the solution (free cells). Maximum zinc recovery in the column was achieved about 76% using medium free of initial ferrous ion and 11.4 g/L of ferric ion (medium 2) at pH 1.5. The extent of leaching of sphalerite ore with bacteria was significantly higher than that without bacteria (control) in the presence of ferrous ions. Fe(III) had a strong influence in zinc extraction, and did not adversely affect the growth of the bacteria population.
在本研究中，考察了Fe(II)和Fe(III)离子的初始浓度以及初始pH值对低品位闪锌矿矿石在浸出柱中进行120天生物浸出的影响，浸出过程分为有菌和无菌两种情况。使用四种不同改良的培养基作为柱进料溶液，以研究Fe(II)和Fe(III)离子初始浓度对锌提取的影响。实验采用实验室规模的柱式浸出反应器进行，该反应器最初接种了从伊朗克尔曼的萨尔切什梅铜精矿中分离出的嗜温铁氧化细菌——氧化亚铁硫杆菌。定期分析流出液中锌、总铁、Fe(II)和Fe(III)的浓度以及pH值。测量溶液中（游离细胞）的细菌数量。在pH值为1.5时，使用不含初始亚铁离子和11.4 g/L铁离子的培养基（培养基2），柱中锌的最大回收率约为76%。在有亚铁离子存在的情况下，闪锌矿矿石的细菌浸出程度明显高于无菌浸出（对照）。Fe(III)对锌的提取有很大影响，且不会对细菌数量的增长产生不利影响。
