Characteristics of the low temperature SCR of NOx with NH3 over TiO2

Azhar Uddin, Koichiro Shimizu, Koji Ishibe, Eiji Sasaoka

Research output: Contribution to journalArticle

32 Citations (Scopus)

Abstract

Low temperature selective catalytic reduction (LT-SCR) of NO + NO2 mixture with NH3 was investigated over TiO2, SiO2 and activated carbon in a conventional flow type fixed-bed reactor at 100 °C under atmospheric pressure. The effects of gas composition such as presence of SO2 and NH3 and the ratio of NO2/NO in the feed-stream on the LT-SCR have been studied. The presence of SO2 and O2 was essential for the selective removal of NO with NH3 over TiO2. The presence of SO2 contributed to the oxidation of NO to NO2 over TiO2. If NO2 existed with NO in the reaction system, the presence of SO2 was not necessary for the removal of NO over TiO2. The following two reactions were suggested to occur over TiO2: NO + NO2 + 2NH3 → 2N2 + 3H2O (1) and 2NO2 + 2NH3 → N2 + NH4NO3 + H2O (2). The reaction (2) occurred on all three catalysts, however the reaction (1) did not proceed significantly over SiO2.

Original languageEnglish
Pages (from-to)178-183
Number of pages6
JournalJournal of Molecular Catalysis A: Chemical
Volume309
Issue number1-2
DOIs
Publication statusPublished - Aug 18 2009

Fingerprint

silicon controlled rectifiers
Selective catalytic reduction
Thyristors
Activated carbon
Atmospheric pressure
Gases
Oxidation
Temperature
Catalysts
carbon
gas composition
activated carbon
Chemical analysis
beds
atmospheric pressure
reactors
catalysts
oxidation
TiO2-SiO2

Keywords

  • Activated carbon
  • Low temperature SCR
  • NO
  • SiO
  • TiO

ASJC Scopus subject areas

  • Catalysis
  • Physical and Theoretical Chemistry
  • Process Chemistry and Technology

Cite this

Characteristics of the low temperature SCR of NOx with NH3 over TiO2. / Uddin, Azhar; Shimizu, Koichiro; Ishibe, Koji; Sasaoka, Eiji.

In: Journal of Molecular Catalysis A: Chemical, Vol. 309, No. 1-2, 18.08.2009, p. 178-183.

Research output: Contribution to journalArticle

Uddin, Azhar ; Shimizu, Koichiro ; Ishibe, Koji ; Sasaoka, Eiji. / Characteristics of the low temperature SCR of NOx with NH3 over TiO2. In: Journal of Molecular Catalysis A: Chemical. 2009 ; Vol. 309, No. 1-2. pp. 178-183.
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