Evolvement of surface property of extracellular polymeric substances of At. ferrooxidans with culture media and time
In order to investigate the relationship among Cu2+ ions, Fe3+ ions and extracellular polymeric substances ( EPS ) during bioleaching chalcopyrite, Acidithiobacillus ferrooxidans were cultured in: ( a) 9K medium; (b)9K medium containing different concentrations of Cu2+ ions; (c)9K media without Fe2+ but containing 1％ chalcopyrite respectively. Then their EPS were extracted, and characterized by measuring FTIR, total sugars and the adsorption amount of Fe3 + and Cu2+ ions. The results indicated that; (1) It was through excreting more EPS rather than through change EPS essence that bacteria resist this disadvantageous environment due to no essential change of the function groups of EPS components under the conditions of different growth periods and culture media; (2) Compared with Fe 2+ ions, Cu2 2+ ions can promote bacteria to produce more EPS, particularly, EPS increased rapidly when the concentration of Cu 2+ ions was more than the tolerable concentration of bacteria; EPS produced by bacteria is (B) >(C) > ( A) ; (3) The adsorption of Fe3+ ions by EPS was (C) > ( B) > (A) and adsorption of Cu2 + ions also was (C) >(B), at the same time, adsorption of Fe 3+ ions always is much more than that of Cu 2+ ions; (4) With the increase of the concentration of Cu 2+ ions during bioleaching chalcopyrite, a number of EPS was produced by bacteria and can adsorb jarosites to form weak ion diffuse barrier layer on chalcopyrite, which was responsible for ultimate passivation of chalcopyrite.
chalcopyrite bioleaching EPS surface property
Runlan Yu Daili Zhong Fadeng Wu Zhijun Peng Jiaju Ji Wenqing Qin Guanzhou Qiu
Key Lab. of Biometallurgy. of Education Ministry, Central South University, 410083, Changsha, China School of Minerals Processing and Bioengineering, Central South University, 410083, Changsha, China
国际会议
The 19th International Biohydrometallurgy Symposium(第19届国际生物湿法冶金大会 IBS2011)
长沙
英文
434-440
2011-09-18（万方平台首次上网日期，不代表论文的发表时间）