Journal of Pure and Applied MicrobiologyVol. 7 No. Special Edition

Effect of Bioleaching on Alkalinene Copper Oxide Ores with Ammonia Producing Strain

Wang Hongjiang1,2, Wu Aixiang*, Xiong Youwei1,2, Hu Kaijian1,2 and Huang Mingqing1,2

1School of Civil and Environment Engineering, University of Science and Technology Beijing, Beijing - 100 83, China. 2State Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety  of Metal Mines, University of Science and Technology Beijing,Beijing - 100 083, China.

Received on 03 March 2013 and accepted on 14 April 2013

 

ABSTRACT

There are mass of studies on ammonia leaching of copper, but few concerning bioleaching under alkalinene system. This paper presents an ammonia-producing strain isolated from soil, which is capable of decomposing urea, identified as Providencia.Sp and designated as strain AJT-1. Then bioleaching of high alkalinene copper oxide ores was carried out in the shake flask with Providencia JAT-1. The influencing parameters investigated include liquid-solid ratio, species and concentration of leaching aid and initial bacteria inoculation size. The results show that the 144h bioleaching yields a copper recovery of 42.35%, which is obtained at liquid-solid ratio of 7:1, ammonium sulfate of 0.024mol/L as the leaching aid, and initial bacteria inoculation of 20%. Based on the copper phase test of leaching residue, we can learn that the most easily leached copper dealing with ammonia strains is secondary copper sulfide, and its leaching rate is as high as 84.26%.

Keywords : Ammonia producing strain; Bioleaching; Alkalinene; Copper ore; Initial inoculation size.