Microbiological reduction of hexavalent chromium by indigenous chromium-resistant bacteria in sand column experiments.
Indigenous bacteria that are resistant to high concentrations of Cr(VI) were isolated from a Cr-contaminated sediment. Sand column experiments were conducted using the isolated bacteria to investigate microbial effects on Cr(VI) reduction in open systems that simulated subsurface conditions. The indigenous Cr-resistant bacteria appeared to reduce Cr(VI) in the column experiments. When 12 mg/L of Cr(VI) was injected into the columns, the removal efficiencies of Cr(VI) by the isolated bacteria were 39.1%, 62.5%, and 63.6% at 24, 48, and 72 h retention times of Cr(VI) solution, respectively. These results imply that the linear velocity of groundwater or pore water should be less than 0.63 cm/h for effective removal of Cr(VI) in subsurface conditions. In comparison, the noninoculated control column did not show a significant variation in dissolved Cr(VI) concentration. The results indicated that reduction of Cr(VI) was occurring in the column due to the activity of the indigenous bacteria.
Lee
Sung-Eun
SE
Research Institute of Engineering Science, Seoul National University, Seoul 151-744, South Korea.
Lee
Jong-Un
JU
Chon
Hyo-Taek
HT
Lee
Jin-Soo
JS
D001419:Bacteria / Q000378:metabolism*; D001426:Bacterial Proteins / Q000032:analysis; D001673:Biodegradation, Environmental; D002857:Chromium / Q000378:metabolism*; D010084:Oxidation-Reduction; D012822:Silicon Dioxide; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*
D001426:Bacterial Proteins; D012989:Soil Pollutants; D002857:Chromium; C074702:chromium hexavalent ion; D012822:Silicon Dioxide