Stoichiometry and kinetic of the aerobic oxidation of phenolic compounds by activated sludge

• Published in: Bioresource technology 2013-05, Vol.136, p.58-65
• Main Authors: Lobo, Cintia C., Bertola, Nora C., Contreras, Edgardo M.
• Format: Article
• Language: English
• Subjects: Acclimatization; Activated sludge; Aerobiosis; Bacteria - metabolism; Biodegradation; Biodegradation, Environmental; Biological and medical sciences; Biological treatment of sewage sludges and wastes; Biotechnology; Degradation; Environment and pollution; Fundamental and applied biological sciences. Psychology; Hydroquinone; Industrial applications and implications. Economical aspects; Kinetics; Oxidation; Oxidation-Reduction; Oxygen Consumption; Phenolic compounds; Phenols - metabolism; Respiration; Respirometry; Sewage - chemistry; Stoichiometry; Time Factors; Toxicity
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2013.02.079

► Study of the aerobic degradation of several phenolic compounds by activated sludge. ► Biodegradation rate: catechol>phenol>>pyrogallol≅resorcinol>hydroquinone. ► Toxicity: pyrogallol>>catechol≅resorcinol>>phenol>hydroquinone. ► Oxidation coefficients are reported. ► The role of some enzymes involved in the degradation pathways is discussed. The aerobic degradation of phenol (PH), catechol (CA), resorcinol (RE), pyrogallol (PY), and hydroquinone (HY) by phenol-acclimated activated sludge was investigated. A Haldane-type dependence of the respiration rate on PH, RE, and HY was observed; CA and PY exhibited a biphasic respiration pattern. According to the initial biodegradation rate, tested compounds were ordered as follows: CA>PH>>PYRE>HY. Also, they exhibited the following degree of toxicity to their own degradation: PY>>CARE>>PH>HY. Oxidation coefficients for PH, PY, RE, and HY were constant as a function of the consecutive additions of the compound. Conversely, an increase of YO/S from 1 to 1.5molO2molCA−1 was observed during repeated additions of CA. The role of some enzymes involved in the aerobic degradation pathways of the tested compounds is discussed and related to the obtained results.