V. Uberoi et Sk. Bhattacharya, EFFECTS OF CHLOROPHENOLS AND NITROPHENOLS ON THE KINETICS OF PROPIONATE DEGRADATION IN SULFATE-REDUCING ANAEROBIC SYSTEMS, Environmental science & technology, 31(6), 1997, pp. 1607-1614
The ability of sulfate-reducing bacteria (SRB)to effectively degrade s
everal substituted and non-substituted aromatic and aliphatic compound
s offers a promising alternative for the treatment of sulfate-containi
ng industrial wastewaters and landfill leachates. For the design of su
lfate-reducing anaerobic treatment systems for such wastewaters, it is
important to determine the effects of toxicants on the kinetics of su
lfate-reducing and methanogenic reactions. Batch kinetic experiments w
ere conducted in the presence and absence of selected organic toxicant
s with a sulfate-reducing propionate enrichment culture. Fourteen chlo
rophenols and four nitrophenols were selected for this study. Toxicity
due to dichlorophenols and trichlorophenols to both propionate and ac
etate degradation was dependent on the substitution position of chlori
ne atoms on the benzene ring. Among the dichlorophenols, 2,3-dichlorop
henol and 2,6-dichlorophenol were the least toxic and 3,5-dichlorophen
ol was the most toxic. Among the trichlorophenols, 2,3,5-trichlorophen
ol and 2,4,5-trichlorophenol were more toxic as compared to 2,3,6-tric
hlorophenol and 2,4,6-trichlorophenol. Toxicity due to the mononitroph
enols was also dependent on the substitution position showing 4-nitrop
henol as the least toxic. All of the selected nitrophenols were more t
oxic to acetate utilization by methanogens than propionate utilization
by the SRB.