Catalysis
AssigneeJohnson Matthey PLC
InventorPaul A. Sermon
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Abstract
This invention relates to the purification of air and other gaseous media. In particular the invention is concerned with the decomposition of one or more of the oxides of nitrogen which may be present in a gas stream also containing gaseous compounds such as carbon monoxide and hydrocarbons. In certain cases, the gas stream may contain a stoichiometric excess of oxygen or an oxidizing agent. The catalyst used in the process of the invention is a mixed oxide of iron and cobalt selected from the group consisting of (a) Co.sup.II.sub.x Fe.sup.II.sub.1-x Fe.sup.III.sub.2 O.sub.4 where x normally has values 0.ltoreq..times..ltoreq.1 and, (b) Co.sup.II Co.sup.III.sub.(x-1) Fe.sup.III.sub.(3-x) O.sub.4 where x normally has values 1.ltoreq..times..ltoreq.3.
Claims10
A process for decomposing NO in air or other gaseous media containing the oxide which includes the step of contacting said air or other gaseous media with a supported catalyst comprising a mixed oxide selected from the group consisting of:
- (a) Co.sub.x.sup.II Fe.sub.1-x.sup.II Fe.sub.2.sup.III O.sub.4 where x normally has values greater than 0 and up to 1 and,
- (b) Co.sup.II Co.sup.III.sub.(x-1) Fe.sup.III.sub.(3-x) O.sub.4 where x normally has values 1.ltoreq.x.ltoreq.3,
- the catalyst support being a corrugated or extended metallic substrate or nichrome wire having deposited thereon a first layer, 0.0004 to 0.001 inch thick, comprising an adherent alumina coating.
Dependencies are inferred from the claim text.