Modeling chlorophenols degradation in sequencing batch reactors with instantaneous feed-effect of 2,4-DCP presence on 4-CP degradation kinetics


ŞAHİNKAYA E., Dilek F. B.

BIODEGRADATION, vol.18, no.4, pp.427-437, 2007 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 18 Issue: 4
  • Publication Date: 2007
  • Doi Number: 10.1007/s10532-006-9077-3
  • Journal Name: BIODEGRADATION
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.427-437
  • Keywords: 4-chlorophenol, 2,4-dichlorophenol, biodegradation kinetics, competent biomass, modeling, sequencing batch reactor, META-CLEAVAGE PATHWAY, ACTIVATED-SLUDGE, BIODEGRADATION KINETICS, 2,4-DICHLOROPHENOL HYDROXYLASE, 4-NITROPHENOL BIODEGRADATION, ORGANIC-COMPOUNDS, WASTE-WATER, 4-CHLOROPHENOL, CULTURE, PURIFICATION
  • Middle East Technical University Affiliated: Yes

Abstract

Two instantaneously fed sequencing batch reactors (SBRs), one receiving 4-chlorophenol (4-CP) (SBR4) only and one receiving mixture of 4-CP and 2,4-dichlorophenol (2,4-DCP) (SBRM), were operated with increasing chlorophenols concentrations in the feed. Complete degradation of chlorophenols and high-Chemical oxygen demand (COD) removal efficiencies were observed throughout the reactors operation. Only a fraction of biomass (competent biomass) was thought to be responsible for the degradation of chlorophenols due to required unique metabolic pathways. Haldane model developed based on competent biomass concentration fitted reasonably well to the experimental data at different feed chlorophenols concentrations. The presence of 2,4-DCP competitively inhibited 4-CP degradation and its degradation began only after complete removal of 2,4-DCP. Based on the experimental results, the 4-CP degrader's fraction in SBRM was estimated to be higher than that in SBR4 since 2,4-DCP degraders were also capable of degrading 4-CP due to similarity in the degradation pathways of both compounds.