Anaerobic biodegradability of alkylphenols and fuel oxygenates in the presence of alternative electron acceptors.
Alkylphenols and fuel oxygenates are important environmental pollutants produced by the petrochemical industry. A batch biodegradability test was conducted with selected ortho-substituted alkylphenols (2-cresol, 2,6-dimethylphenol and 2-ethylphenol), fuel oxygenates (methyl tert-butyl ether, ethyl tert-butyl ether and tert-amylmethyl ether) and tert-butyl alcohol (TBA) as model compounds. The ortho-substituted alkylphenols were not biodegraded after 100 days of incubation under methanogenic, sulfate-, or nitrate-reducing conditions. However, biodegradation of 2-cresol and 2-ethylphenol (150 mg l(-1)) was observed in the presence of Mn (IV) as electron acceptor. The biodegradation of these two compounds took place in less than 15 days and more than 90% removal was observed for both compounds. Mineralization was indicated since no UV-absorbing metabolites accumulated after 23 days of incubation. These alkylphenols were also slowly chemically oxidized by Mn (IV). No biodegradation of fuel oxygenates or TBA (1 g l(-1)) was observed after 80 or more days of incubation under methanogenic, Fe (III)-, or Mn (IV)-reducing conditions, suggesting that these compounds are recalcitrant under anaerobic conditions. The fuel oxygenates caused no toxicity towards acetoclastic methanogens activity in anaerobic granular sludge.
Puig-Grajales
L
L
Programa de Biotecnología del Petróleo, Instituto Mexicano del Petróleo, México, D.F.
Tan
N G
NG
van der Zee
F
F
Razo-Flores
E
E
Field
J A
JA
D000693:Anaerobiosis; D001421:Bacteria, Anaerobic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D003408:Cresols / Q000378:metabolism; D004785:Environmental Pollutants / Q000378:metabolism*; D004987:Ethers / Q000378:metabolism*; D005019:Ethyl Ethers / Q000378:metabolism; D019605:Euryarchaeota / Q000378:metabolism*; D008697:Methane / Q000378:metabolism; D008738:Methyl Ethers / Q000378:metabolism; D009566:Nitrates / Q000378:metabolism; D010084:Oxidation-Reduction; D010636:Phenols / Q000378:metabolism*; D013431:Sulfates / Q000378:metabolism; D014106:Tosylarginine Methyl Ester / Q000378:metabolism; D014992:Xylenes / Q000378:metabolism; D020002:tert-Butyl Alcohol / Q000378:metabolism
D003408:Cresols; D004785:Environmental Pollutants; D004987:Ethers; D005019:Ethyl Ethers; D008738:Methyl Ethers; D009566:Nitrates; D010636:Phenols; D013431:Sulfates; D014992:Xylenes; C043243:methyl tert-butyl ether; C098546:ethyl tert-butyl ether; D014106:Tosylarginine Methyl Ester; C036531:2,6-xylenol; D020002:tert-Butyl Alcohol; D008697:Methane; C034047:2-cresol