Patent · US Expired

Process for the removal from gases of nitrogen oxides NOx by selective catalytic reduction (SCR) using ammonia over zeolite catalysts not causing the formation of nitrogen protoxide

US6221324A · kind A · utility

25Cited by
6References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 30, 1998
Grant dateApr 24, 2001
Priority date
Expiry dateOct 30, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02C20/10
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Zeolites partially exchanged with copper, in particular faujasites, in which the copper does not largely occupy the small cages (for example the sodalite cages of the faujasites), are used as non-nitrogen-protoxide-generating SCR catalysts. Particular attention is drawn to certain mixed rare-earth/copper zeolites. The selectivity of the reduction of NOx to N.sub.2 is correlated with the TPR diagram of the catalysts.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.