Two-step modeling of the biodegradation of phenol by an acclimated activated sludge

Biodegradation of Phenol by Unacclimated and Phenol-acclimated Activated Sludge: Effects of Operational Factors on Biodegradation Efficiency and Kinetics

“…10 In the study by Vazquez-Rodriguez et al, no lag phase was found during the biodegradation of phenol by activated sludge acclimated to 700 mg l −1 of phenol. 13 Similar result was reported by Janeczko and Oleszkiewicz that immediate biodegradation of 2-nitrophenol (2NP) without any lag was shown using acclimated activated sludge, whereas a 170 to 230 h lag was observed before the initiation of 2NP removal using unacclimated activated sludge.…”

“…Studies have shown the complete mineralisation of various phenolic compounds using activated sludge obtained from sequencing batch reactor systems. [10][11][12][13] Nonetheless, it was observed that the biodegradation of phenolic compounds was mostly conducted using activated sludge that was acclimated to the target compound beforehand. 2,10,13,14 Acclimated activated sludge consists of microorganisms with adjusted morphological, behavioural, physical or biochemical traits in response to changes in the environment.…”

Modelling the change in the oxidation coefficient during the aerobic degradation of phenol by acclimated activated sludge

“…Sample digestion (2 h, 150 o C) was performed in a Hach COD Reactor 45600; a Hach DR 2000 photometer was used for the absorbance determination step. Total phenol (TPh) concentration of the supernatant was measured using the 4-aminoantipyrine (4-AAP) method (Vazquez-Rodriguez et al, 2006). This method uses 2 reagents, 4-AAP (20.8 mM of 4-AAP in 0.25 M NaHCO 3 ) and ferricyanide (83.4 mM of K 3 Fe(CN) 6 in 0.25 M NaHCO 3 ), as colour-generating substrates when combined with phenolic compounds.…”

Aerobic biodegradation of a mixture of monosubstituted phenols in a sequencing batch reactor

“…This hypothesis was based on the fact that the kinetics of biodegradation of a phenolic compound could be altered by the presence of other phenols that microorganisms can oxidize [25]. Moreover, the kinetics could be influenced by the formation and accumulation of metabolic intermediates [26][27][28]. For example, Bordel et al [26] found that the aerobic biodegradation of benzene by Pseudomonas putida F1 could be inhibited by the accumulation of catechol, an intermediate in the metabolic pathway.…”

“…In that case, catechol could act 7 as an inhibitor for benzene oxidation or as a self-inhibitor for catechol oxidation. Vázquez-Rodriguez et al [27] also found that the aerobic biodegradation of phenol can be modelled through the formation of metabolic intermediates that could act as inhibitors of the phenol oxidation or as self-inhibitors of oxidations.…”