Modelling biodegradation of nonylphenol ethoxylate in acclimated and non-acclimated microbial cultures.
The biodegradation and inhibition kinetics of a commercial nonylphenol ethoxylate formulation were modelled for an activated sludge system fed with a synthetic substrate and nonylphenol ethoxylate mixture. Kinetic and stoichiometric coefficients of the proposed activated sludge model were obtained by employing on-line respirometry. Experimental as well as model results confirmed that nonylphenol ethoxylate exhibited non-competitive inhibition on the hydrolysis process with a coefficient of 150mg/L on the basis of COD and negatively influenced biomass growth through a competitive inhibition mechanism with a coefficient of 500mg/L on the basis of COD, when the biomass was not acclimated. Upon acclimation of the activated sludge system, the inhibition concentration for non-competitive inhibition on hydrolysis was increased to 5000mg/L, practically showing no inhibition, and the coefficient of competitive inhibition increased to 450mg/L, corresponding to a significant decrease in the inhibitory effects of NPEO on growth.
Karahan
Ozlem
O
Istanbul Technical University, Faculty of Civil Engineering, Department of Environmental Engineering, 34469 Maslak, Istanbul, Turkey.
Olmez-Hanci
Tugba
T
Arslan-Alaton
Idil
I
Orhon
Derin
D
D000064:Acclimatization; D001419:Bacteria / Q000166:cytology* / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002138:Calibration; D003198:Computer Simulation; D005026:Ethylene Glycols / Q000378:metabolism*; D007700:Kinetics; D008954:Models, Biological; D010100:Oxygen / Q000378:metabolism; D013997:Time Factors
D005026:Ethylene Glycols; C021754:terics; D010100:Oxygen