Biotreatment of Cr(VI) contaminated waters by sulphate reducing bacteria fed with ethanol.
J Hazard Mater
; 199-200: 186-92, 2012 Jan 15.
Article
in En
| MEDLINE
| ID: mdl-22104763
ABSTRACT
Biological treatment of Cr(VI) contaminated waters was performed in fixed bed reactors inoculated with SRB (sulphate-reducing bacteria) growing on ethanol. Treatment efficiency was evaluated by checking chemical abatement of Cr(VI) and by ecotoxicological tests using the nematode Caenorhabditis elegans. A preliminary comparison between ethanol and lactate was performed, denoting that using ethanol, the same values of final sulphate abatement were obtained. In addition ethanol showed to be a substrate more competitive than lactate in kinetic terms. Fixed bed column reactors were continuously fed with a solution containing sulphates (3 g L(-1)), ethanol (1.5 g L(-1)) and Cr(VI) (50 mg L(-1)). At steady state the column inoculated with SRB removed 65 ± 5% of sulphate and 95 ± 5% of chromium. Bioactive removal mechanisms predominated over biosorption. Diminution of Cr(VI) toxicity was assessed by using the nematode C. elegans as a test organism showing that the survival of nematodes was 20% in the presence of the untreated influent and raised up to 53% when the nematodes were exposed to the treated effluent.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Sulfates
/
Bacteria
/
Water Pollutants, Chemical
/
Biodegradation, Environmental
/
Chromium
Limits:
Animals
Language:
En
Journal:
J Hazard Mater
Journal subject:
SAUDE AMBIENTAL
Year:
2012
Document type:
Article
Affiliation country:
Italy