Abstract: An ammonia slip catalyst having an SCR catalyst and an oxidation catalyst comprising at least two metals, each of which is selected from a specific group, and a substrate upon which at least oxidation catalyst is located is described. The ammonia slip catalyst can have dual layers, with one of the layers containing an SCR catalyst, a second layer containing the oxidation catalyst with comprises at least two metals, each of which is selected from a specific group, and the ammonia slip catalyst does not contain a platinum group metal. Methods of making and using the ammonia slip catalyst to reduce ammonia slip are described.

Abstract: Provided is an ammonia slip catalyst article having supported palladium in a top or upstream layer for oxidation of carbon monoxide and/or hydrocarbons, an SCR catalyst either in the top layer or in a separate lower or downstream layer, and an ammonia oxidation catalyst in a bottom layer. Also provided are methods for treating an exhaust gas using the catalyst article, wherein the treatment involves reducing the concentrations of ammonia and optionally carbon monoxide and/or hydrocarbons in the exhaust gas.

Abstract: A catalyst article for treating an emission gas is provided comprising (a) a first catalyst layer having a plurality of consecutive sub-layers, wherein each sub-layer includes vanadium on a first refractory metal oxide support selected from alumina, titania, zirconia, ceria, silica, and mixtures of these; (b) a second catalyst layer comprising one or more noble metals disposed on a second refractory metal oxide support; and (c) a substrate, wherein the first and second catalyst layers are on and/or within the substrate.

Abstract: Provided is a catalyst article for treating an emission gas comprising (a) a noble metal catalyst layer comprising one or more noble metals disposed on a first refractory metal oxide support; and (b) a vanadium catalyst layer comprising vanadium pre-fixed on a second refractory metal oxide support selected from alumina, titania, zirconia, ceria, silica, and mixtures of these, wherein the first catalyst layer is in physical contact with said second catalyst layer. Also provided is a method for making such a catalyst article, a method for treating gas emissions using such an article, and an emission gas treatment system incorporating such an article.