Study on Reduction of Hexavalent Chromium by Sulfate-reducing Bacteria

Several Sulfate E Reducing Bacteria (SRB) strains, isolated from soil, were able to grow in the medium containing 800 mg/L chromium(Ⅵ), The Cr(Ⅵ) disappeared when the strain 2-S-8 grew in the medium containing 75 mg/L Cr(Ⅵ) for 36 h. The strain was identified as Desulfovibrio sp. The results showed that high-toxic Cr(Ⅵ) was reduced to hypo-toxic Cr(Ⅲ) by SRB, and the Cr(Ⅵ) reduction was related to the reduction of sulfate, which was mainly carried out effect by metabolin of SRB.