Anaerobic degradation kinetics of 2,4-dichlorophenol (2,4-DCP) with linear sorption

Abstract

Degradation of 2,4-DCP by acclimated anaerobic granules enriched at two specific loading rates was examined experimentally in batch mode. The data from process curves were analyzed by nonlinear regression to estimate parameters in the Haldane inhibition equation and one of its modified forms to obtain quantitative information on degradation kinetics. Linear sorption kinetics of 2,4-DCP were employed in data treatment to discriminate between the effects of sorption and biodegradation. It was observed that the modified inhibition equation described experimental data better than the Haldane inhibition equation since the later failed to predict the trend in experimental data. Parameter values estimated with the modified inhibition equation for two types of anaerobic granule, were 0.14 and 0.17 mg/gVSS.h for maximum degradation rate, k; 2.07 and 2.06 mg/L for saturation coefficient, Ks, and 65.1 and 67.5 mg/L for inhibition coefficients, respectively. On the basis of 2,4-DCP toxicity effects on the two anaerobic granule types, it was found that the liquid phase concentration determined toxicity and degradation of the chemical.