Characteristics of Reduce Cr(VI) by Desulfovibrio SRB7

Abstract:

Pollution of heavy metal chromium Cr(VI) in environment would cause cancer. Chromium Cr(VI) was defined as one of 129 important pollutants by American EPA. This study was carried out on the conditions of removal Cr(VI) including different originated pH, temperature, carbon source and the volume ratio of bacteria to wastewater using an acidproof Desulfovibrio (SRB7) which was departed from sewage sludge effluent water of a chemical plant. Meanwhile the characteristics of reducing Cr(VI) through sulfureted hydrogen approach, electron transfer approach and adsorption approach were studied. The results showed that the conditions of removal Cr(VI) were as follows: pH 7.5, temperature 36°C, using lactate sodium as the carbon sources and the volume ratio of bacteria to wastewater at 1:5(V/V), when the influent concentration was 50 mg/L. In this study for characteristics of reducing Cr(VI) by SRB7, adsorption approach couldn’t remove Cr(VI); electron transfer approach which removed 51.42% of the Cr(VI) at 24 h, was not preponderant in the process of reduce Cr(VI); sulfureted hydrogen approach which removed 78.02% of the Cr(VI) at 24 h, was preponderant in the process of reduce Cr(VI).