Nitric oxide reduction in BioDeNOx reactors: Kinetics and mechanism

P. van der Maas, I. Manconi, A. Klapwijk

Research output: Contribution to journalArticleAcademicpeer-review

26 Citations (Scopus)

Abstract

Biological reduction of nitric oxide (NO) to di-nitrogen (N-2) gas in aqueous Fe(II)EDTA(2-) solutions is a key reaction in BioDeNOx, a novel process for NOx removal from flue gases. The mechanism and kinetics of the first step of NO reduction, that is, the conversion of NO to N2O, was determined in batch experiments using various types of inocula. Experiments were performed in Fe(II)EDTA medium (5-25 mM) under BioDeNOx reactor conditions (55 degrees C, pH 7.2 +/- 0.2) with ethanol as external electron donor. BioDeNOx reactor mixed liquor gave the highest: NO reduction rates ( +/- 0.34 nmol s(-1) mg(prot)(-1)) with an estimated K value for NO lower than 10 nM. The specific NO (to N2O) reduction rate depended on the NO (aq) and Fe(II)EDTA(2-) concentration as well as the temperature. The experimental results, complemented with kinetic and thermodynamic considerations, show that Fe(II)EDTA, and not ethanol, is the primary electron donor for NO reduction, that is, the BioDeNOx reactor medium (the redox system Fe(II) EDTA(2-)/Fe (III) EDTA(-)) interferes with the NO reduction electron transfer chain and thus enhances the NO denitrification rate.
Original languageEnglish
Pages (from-to)1099-1107
JournalBiotechnology and Bioengineering
Volume100
Issue number6
DOIs
Publication statusPublished - 2008

Keywords

  • paracoccus-denitrificans
  • biological reduction
  • complex
  • system
  • iron

Fingerprint Dive into the research topics of 'Nitric oxide reduction in BioDeNOx reactors: Kinetics and mechanism'. Together they form a unique fingerprint.

  • Cite this