Selective catalytic reduction failure of low NH3-NOx ratio

Piqiang Tan; Xiaoyu Li; Shiyan Wang; Zhiyuan Hu; Diming Lou

Your Location：

Home >

Browse articles >

Selective catalytic reduction failure of low NH₃-NO_x ratio

Catalysis, Kinetics and Reaction Engineering | Updated：2026-01-06

- Selective catalytic reduction failure of low NH₃-NO_x ratio
- Chinese Journal of Chemical Engineering Vol. 32, Issue 4, Pages: 231-240(2021)
- Affiliations：
  
  School of Automobile Studies, Tongji University,Shanghai,China,201804
- Author bio：
- Funds：
- DOI：
  CLC：
- Published：2021
- Accepted：
Scan QR Code
-NO
DOI：

-NO DOI：

摘要

Abstract

An insufficient amount of NH

(ammonia) will reduce the conversion efficiency of NO

which may lead to excess NO

emissions

resulting in NH

-SCR failure. In this article

SCR failure caused by a low NH

-NO

ratio is studied systematically by experiments. The main reasons for a low NH

-NO

ratio in SCR include insufficient urea injection

hydrothermal aging of catalysts and urea crystallization. It was found from an insufficient urea injection experiment that with the increase of NH

-NO

ratio

the NO

conversion efficiency of the SCR system increased

but the ammonia leakage also increased. The main influencing factors of NO

conversion efficiency are different under different NH

-NO

ratios. A flow reactor system was used in the catalyst hydrothermal aging experiment to investigate the effect of hydrothermal aging on catalyst activity. After a 24 h hydrothermal aging experiment at 800℃

the NO

conversion efficiency of the copper-based zeolite catalysts d

ecreased significantly at the boundary of medium and low temperature regions. And the NO

-NO

ratio in the mixture had a significant effect on the catalytic performance. Thermogravimetry coupled to Fourier transform infrared spectroscopy (TG-FTIR) was used to analyze the composition of urea deposits in a urea deposits analysis experiment. It was found that the main components of urea deposits were urea and isocyanic acid (HNCO). Preventing HNCO polymerization

especially the formation of CYA

can decrease the formation of urea deposits.

关键词

Keywords

references

Views

303

Downloads

CSCD

Alert me when the article has been cited

Submit

Tools

Publicity Resources

Vanadium oxide nanotubes for selective catalytic reduction of NOx with NH3

Temperature-dependent pyrolysis product modulation driven by thermal pretreatment of Shendong coal

Migration pathway of nitrogen and phosphorus in municipal sludge during three thermochemical transformation ways

Humification of organic matter and passivation of heavy metals during the hydrothermal carbonization of swine manure

Zn2+ significantly enhances the performance of petal-like Co-naphthalenetetracarboxylic acid MOF as an anode material for lithium-ion batteries

Related Author

Seyed Mahdi Mousavi

Qiang Luyao

Bai Boyang

Sun Ming

Song Dengmeng

Hou Boli

Gao Ting

Ma Xiaoxun

Related Institution

Faculty of Chemistry, University of Kashan, Kashan

College of Chemistry and Chemical Engineering, Xi'an Shiyou University

Shaanxi Engineering Research Center of Green Low-carbon Energy Materials and Processes, Xi'an Shiyou University

College of Chemistry and Materials Science, Weinan Normal University

School of Chemical Engineering, Northwest University

⁰