Patent · US Expired

Method for reducing nitrogen oxides in flue gases with an arsenic resistant catalyst

US5433935A · kind A · utility

0Cited by
3References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 22, 1993
Grant dateJul 18, 1995
Priority date
Expiry dateSep 22, 2013

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D53/8628
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An arsenic-resistant composite oxide catalyst containing oxides of at least the metals vanadium and molybdenum, in particular for reducing nitrogen oxides in flue gases in the presence of a reducing agent, such as ammonia or carbon monoxide, includes at least one composite oxide phase with a general formula V.sub.x Mo.sub.y O.sub.32, where x+y.ltoreq.12 and where x.gtoreq.1 and y.gtoreq.1, and optionally a MoO.sub.3 phase. A method for producing an arsenic-resistant composite oxide catalyst includes mixing vanadium oxide and molybdenum oxide or a precursor thereof with one another to form a mixture, heating the mixture to a temperature at which a mixture of oxides is present, preferably in completely molten form, then cooling down the mixture to form at least one composite oxide phase with a general formula V.sub.x Mo.sub.y O.sub.32, and then subjecting the composite oxide phase to a reducing treatment to prepare a lower-oxygen composite oxide phase with the same structure.

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