title: Anaerobic degradation of nonylphenol in sludge.
abstract: We investigated the effects of various factors on the anaerobic degradation of nonylphenol (NP) in sludge. NP (5 mg/l) anaerobic degradation rate constants were 0.029 1/day for sewage sludge and 0.019l/day for petrochemical sludge, and half-lives were 23.9 days and 36.5 days respectively. The optimal pH for NP degradation in sludge was 7 and the degradation rate was enhanced when the temperature was increased. The addition of yeast extract (5 mg/l) or surfactants such as brij 30 or brij 35 (55 or 91 microM) also enhanced the NP degradation rate. The addition of aluminum sulfate (200 mg/l) inhibited the NP degradation rate within 84 days of incubation. The high-to-low order of degradation rates was: sulfate-reducing conditions>methanogenic conditions>nitrate-reducing conditions. Sulfate-reducing bacteria, methanogen, and eubacteria are involved in the degradation of NP, sulfate-reducing bacteria being a major component of sludge.
authors.affiliation: Department of Microbiology, Soochow University, Shih Lin, Taipei 111, Taiwan. bvchang@mail.scu.edu.tw
authors.forename: B V
authors.initials: BV
authors.lastname: Chang
authors.forename: F
authors.initials: F
authors.lastname: Chiang
authors.forename: S Y
authors.initials: SY
authors.lastname: Yuan
mesh_terms: D000693:Anaerobiosis; D001421:Bacteria, Anaerobic / Q000737:chemistry / Q000378:metabolism; D001673:Biodegradation, Environmental; D019149:Bioreactors; D006207:Half-Life; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D010636:Phenols / Q000737:chemistry*; D012722:Sewage / Q000032:analysis*; D013696:Temperature
chemical_list: D010636:Phenols; D012722:Sewage; C025256:nonylphenol