Bioleaching of Major, Rare Earth, and Radioactive Elements from Red Mud by using Indigenous Chemoheterotrophic Bacterium Acetobacter sp.

Minerals

Xiaoqing Wang¹  Wenjie Tian¹  Yang Qu¹  Ben Shi¹  Hui Li¹  Minjie Yao²  Ying Zhang³ 

[1] Department of Environmental Engineering and Chemistry, Luoyang Institute of Science and Technology, Luoyang 471023, China;Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, University of Chinese Academy of Sciences, Sichuan 610041, China;School of Resources and Environment Engineering, Guizhou Institute of Technology, Guiyang 550003, China;

关键词: chemoheterotrophic bacterium;    Acetobacter;    red mud;    bioleaching;    radioactive elements;   

DOI  :  10.3390/min9020067

来源: DOAJ

【 摘 要 】

The aim was to study the bioleaching performance of chemoheterotrophic bacterium involved in leaching of major, rare earth, and radioactive elements from red mud (RM), and to explore the underlying mechanism. An acid-producing bacterium, identified as Acetobacter sp., was isolated from RM impoundment and used in the bioleaching experiments under one-step, two-step and spent medium process at up to 10% pulp density. The results showed that the leaching ratios of Al, Lu, Y, Sc, and Th were 55%, 53%, 61%, 52%, and 53% respectively under one-step process at 2% pulp density. Under both one- and two-step processes at 2% pulp density, the radioactivity of bioleached RM can meet the relevant regulation in China. The total amount of organic acids excreted by Acetobacter sp. increased with an increase of RM pulp density. After bioleaching, contents of hematite and gibbsite decreased but perovskite increased in RM. Micromorphology analysis indicated that the cells of Acetobacter sp. adhered to RM particles and formed large-size aggregates, and a new crystal of weddellite emerged. In view of the shorter lag phase and smaller biomass comparing to fungi even under direct contact with RM, bacterium Acetobacter sp. is supposed to apply to in situ heap or dump bioleaching of RM.

【 授权许可】

Unknown