title: Effect of phenol and acetate addition on 2-chlorophenol consumption by a denitrifying sludge.
abstract: Chlorophenols are widely distributed in the environment. Various strategies have been used to improve their biological elimination under anaerobic conditions; however, such information is still scarce. The aim of this study was to evaluate in batch assays the consumption of 2-chlorophenol (2-CP) by a denitrifying sludge and the influence of acetate or phenol as co-substrates in the 2-CP consumption. It was observed that phenol (69 and 92 mg phenol-C L(-1)) and acetate (60 and 108 mg acetate-C L(-1)) enhanced 2-CP consumption by the denitrifying sludge, increasing both the efficiency (up to 100%) and specific rate of 2-CP consumption. When phenol was added at 92 mg C L(-1), the specific consumption rate of 2-CP increased 2.6 times with respect to the control lacking co-substrates, whereas with acetate (108 mgC L(-1)) the increase was 9.0 times. Acetate appeared to be a better co-substrate for 2-CP consumption, obtaining a specific consumption rate of 2.48 +/- 0.14 mg 2-CP-C g(-1) VSS d(-1) at 108 mg acetate-C L(-1). The mass balance analysis indicated that the denitrifying sludge was able to simultaneously mineralize 2-CP, phenol or acetate (E2-CP, E(Phenol), and E(Acetate) close to 100% [E = consumption efficiency], Y(HCO3-) of 0.90 +/- 0.10 [Y = yield]) and reduce nitrate to nitrogen gas (E(NO3-) of 100% and Y(N2) of 0.96 +/- 0.02). It was shown that the addition of co-substrates as phenol or acetate could be a good alternative for improving the elimination of chlorophenols from wastewaters by denitrifying sludges.
authors.affiliation: Departamento de Biotecnología, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Vicentina, C.P 09340 Iztapalapa, DF, Mexico.
authors.forename: Emir
authors.initials: E
authors.lastname: Martínez-Gutiérrez
authors.forename: Humberto
authors.initials: H
authors.lastname: González-Márquez
authors.forename: Sergio
authors.initials: S
authors.lastname: Martínez-Hernández
authors.forename: Anne-Claire
authors.initials: AC
authors.lastname: Texier
authors.forename: Flor de María
authors.initials: Fde M
authors.lastname: Cuervo-López
authors.forename: Jorge
authors.initials: J
authors.lastname: Gómez
mesh_terms: D000085:Acetates / Q000378:metabolism*; D002733:Chlorophenols / Q000378:metabolism*; D058440:Denitrification; D004785:Environmental Pollutants / Q000378:metabolism*; D019800:Phenol / Q000378:metabolism*; D012722:Sewage
chemical_list: D000085:Acetates; D002733:Chlorophenols; D004785:Environmental Pollutants; D012722:Sewage; D019800:Phenol; C030683:2-chlorophenol