Chaerun Siti Khodijah, Putri Edina Amadea, Mubarok Mohammad Zaki
Department of Metallurgical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Bandung, Indonesia.
Geomicrobiology-Biomining and Biocorrosion Laboratory, Microbial Culture Collection Laboratory, Biosciences and Biotechnology Research Center (BBRC), Institut Teknologi Bandung, Bandung, Indonesia.
Front Microbiol. 2020 Oct 8;11:557548. doi: 10.3389/fmicb.2020.557548. eCollection 2020.
Biohydrometallurgy is believed to be a promising future study field for the recovery of lead (Pb) from ores/concentrates since the pyrometallurgical/hydrometallurgical processes have been largely applied to recover Pb to date, which operates at high temperature and generates volatile Pb matters that are hazardous and carcinogenic to human health. Hence, the main purpose of this study was to investigate the biohydrometallurgical extraction of Pb from the Indonesian galena concentrate through bioleaching using an iron- and sulfur-oxidizing mixotrophic bacterium (identified as sp.). The bioleaching experiments were conducted in shake flasks containing the modified LB broth medium supplemented with galena concentrate with a particle size of = 75 μm at room temperature. Both semi-direct and direct bioleaching methods were employed in this study. The bacterium was able to extract lead (Pb) from galena concentrate with high selectivity to Cu and Zn (0.99 and 0.86, respectively). The highest extraction level of 90 g lead dissolved/kg galena concentrate was achieved using direct bioleaching method at bioleaching conditions of 2% pulp density, 5 g/L FeCl, 50 g/L NaCl, 20 g/L molasses and a rotation speed of 180 rpm at room temperature (25°C). The addition of FeCl, NaCl, and molasses increased the lead leaching efficiencies, which were also evidenced by the FTIR, XRD, and SEM-EDS analyses. From industrial and commercial standpoints, the selective bioleaching represented in this study may be beneficial to the development of lead leaching from sulfide minerals, since insoluble anglesite (PbSO) precipitates are formed during ferric sulfate oxidation, thus making the recovery of lead through bioleaching unpractical.
生物湿法冶金被认为是未来从矿石/精矿中回收铅（Pb）的一个有前景的研究领域，因为迄今为止火法冶金/湿法冶金工艺在很大程度上已被用于回收铅，这些工艺在高温下运行，并产生对人体健康有害且致癌的挥发性铅物质。因此，本研究的主要目的是通过使用铁和硫氧化混合营养细菌（鉴定为 菌）进行生物浸出，研究从印度尼西亚方铅矿精矿中生物湿法冶金提取铅。生物浸出实验在室温下含有添加了粒径为 = 75 μm 的方铅矿精矿的改良 LB 肉汤培养基的摇瓶中进行。本研究采用了半直接和直接生物浸出方法。该细菌能够从方铅矿精矿中提取铅（Pb），对铜和锌具有高选择性（分别为 0.99 和 0.86）。在室温（25°C）下，采用直接生物浸出方法，在生物浸出条件为 2%矿浆密度、5 g/L FeCl、50 g/L NaCl、20 g/L 糖蜜和 180 rpm 转速下，实现了最高提取水平为 90 g 溶解铅/千克方铅矿精矿。FeCl、NaCl 和糖蜜的添加提高了铅的浸出效率，FTIR、XRD 和 SEM - EDS 分析也证明了这一点。从工业和商业角度来看，本研究中所代表的选择性生物浸出可能有利于从硫化物矿物中浸出铅的开发，因为在硫酸铁氧化过程中会形成不溶性硫酸铅矿（PbSO）沉淀，从而使得通过生物浸出回收铅不切实际。
