中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 29 No. 6 June 2019 |
（1. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China;
2. Shandong Provincial Key Laboratory of Soil Conservation and Environmental Protection, College of Resources and Enviroment, Linyi University, Linyi 276000, China;
3. Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China）
Abstract:The catalysis of four carbon materials including artificial graphite (AG), carbon black (CB), activated carbon (AC) and carbon nanotube (CN) on chalcopyrite bioleaching by mixed moderate thermophiles was comparatively investigated. In AC and AG added bioleaching groups, low solution pH and suitable redox potential values, high total iron and ferric iron concentrations, and large number of adsorbed bacteria were obtained, resulting in high copper extractions. CB and CN inhibited the growth of bioleaching bacteria and led to the low bioleaching efficiency. X-ray diffraction analysis showed that jarosite and sulfur film were the main components of passivation layer with the addition of AG and AC, but did not hinder the dissolution of chalcopyrite. Microbial community structures of free and attached cells in AC and AG added groups changed dramatically compared with mixed moderate thermophiles. The sulfur-oxidizing bacteria of A. caldus S1 strain dominated the microbial community (93%-98%) at the end of bioleaching. The iron-oxidizing bacteria of L. ferriphilum YSK only accounted for low percentage (1%-2%).
Key words: chalcopyrite; leaching; carbon material; mixed moderate thermophiles; microbial community structure
