Microbial Detoxification of Hexavalent Chromium from Chromium-Containing Slag

Abstract

In this paper,treatment and recovery of hexavalent chromium(Cr(Ⅵ)) from chromium-containing slag by bacteria was studied.The work showed that a bacterial strains of Ch-1 isolated from chromium-containing slag can efficiently accelerate Cr(Ⅵ) leaching and remove it.Moreover,bacteria Ch-1 can effectively change the structure of chromium-containing slag by Scanning Electron Microscopy(SEM) and the Energy Dispersive X-Ray(EDX),which is benefitial to Cr(Ⅵ) leaching and its detoxification by changing Cr(Ⅵ) to Cr(Ⅲ).The effect of detoxification by bacteria of Ch-1 is obvious,the toxicity in leached slag was 3.3 μg/g lower than the national standard of 5 μg/g,and the recovery rates of hexavalent chromium are more than 90%.