Selective removal of transition metals from acidic mine waters by novel consortia of acidophilic sulfidogenic bacteria
Article first published online: 6 SEP 2011
© 2011 The Authors. Microbial Biotechnology © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd
Volume 5, Issue 1, pages 34–44, January 2012
How to Cite
Ňancucheo, I. and Johnson, D. B. (2012), Selective removal of transition metals from acidic mine waters by novel consortia of acidophilic sulfidogenic bacteria. Microbial Biotechnology, 5: 34–44. doi: 10.1111/j.1751-7915.2011.00285.x
- Issue published online: 14 DEC 2011
- Article first published online: 6 SEP 2011
- Received 10 March, 2011; revised 15 June, 2011; accepted 27 June, 2011.
Two continuous-flow bench-scale bioreactor systems populated by mixed communities of acidophilic sulfate-reducing bacteria were constructed and tested for their abilities to promote the selective precipitation of transition metals (as sulfides) present in synthetic mine waters, using glycerol as electron donor. The objective with the first system (selective precipitation of copper from acidic mine water containing a variety of soluble metals) was achieved by maintaining a bioreactor pH of ∼2.2–2.5. The second system was fed with acidic (pH 2.5) synthetic mine water containing 3 mM of both zinc and ferrous iron, and varying concentrations (0.5–30 mM) of aluminium. Selective precipitation of zinc sulfide was possible by operating the bioreactor at pH 4.0 and supplementing the synthetic mine water with 4 mM glycerol. Analysis of the microbial populations in the bioreactors showed that they changed with varying operational parameters, and novel acidophilic bacteria (including one sulfidogen) were isolated from the bioreactors. The acidophilic sulfidogenic bioreactors provided ‘proof of principle’ that segregation of metals present in mine waters is possible using simple online systems within which controlled pH conditions are maintained. The modular units are versatile and robust, and involve minimum engineering complexity.