Microbial reduction of hexavalent chromium by landfill leachate

• Published in: Journal of hazardous materials Vol. 142; no. 1; pp. 153 - 159
• Main Authors: Li, Yarong, Low, Gary K.-C., Scott, Jason A., Amal, Rose
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 02.04.2007; Elsevier
• Subjects: Applied sciences; Bacteria - metabolism; Bacteria biomass; Biomass; Chromium - metabolism; Cr(VI); Exact sciences and technology; General treatment and storage processes; Hydrogen-Ion Concentration; Municipal landfill leachate; Organic matter; Pollution; Soil Microbiology; Soil Pollutants - metabolism; Wastes; Water Pollutants, Chemical - metabolism; Organic matter; Cr(VI); Municipal landfill leachate; Bacteria biomass; Waste dumping; pH; Bacteria; Microbial biomass; Leachate
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2006.07.069

The reduction of hexavalent chromium (Cr(VI)) in municipal landfill leachates (MLL) and a non-putrescible landfill leachate (NPLL) was investigated. Complete Cr(VI) reduction was achieved within 17 days in a MLL when spiked with 100 mg l −1 Cr(VI) or less. In the same period, negligible Cr(VI) reduction was observed in NPLL. In MLL, Cr(VI) reduction was demonstrated to be a function of initial Cr(VI) concentration and bacterial biomass and organic matter concentrations. The bacteria were observed to tolerate 250 mg l −1 Cr(VI) in MLL and had an optimal growth activity at pH 7.4 in a growth medium. The MLL also possessed an ability to sequentially reduce Cr(VI) over three consecutive spiking cycles.