# US 2014/0154163 A1 · Ammonia oxidation catalyst > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0154163 A1 - Document ID: US20140154163A1 - Status: Published application - Kind: A1 - Application number: 14/091,967 - Filed: 2013-11-27 - Published: 2014-06-05 - Earliest claimed: 2012-11-30 - Assignees: Johnson Matthey Public Limited Company - Applicants: Johnson Matthey Public Limited Company - Inventors: PAUL JOSEPH ANDERSEN; KEVIN DOURA - Web page: https://patentgrep.com/patent/US20140154163A1 ## CPC - B01J 23/6527: {Tungsten} - B01D 53/58: Ammonia - B01D 53/9418: {for removing nitrogen oxides by selective catalytic reduction [SCR] using a reducing agent in a lean exhaust gas} - B01D 53/9436: {Ammonia} - B01J 21/063: {Titanium; Oxides or hydroxides thereof} - B01J 23/22: Vanadium - B01J 23/30: Tungsten - B01J 23/40: of the platinum group metals - B01J 23/42: Platinum - B01J 23/44: Palladium - B01J 35/19: {Catalysts containing parts with different compositions} - B01J 35/56: Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional [3D] monoliths - B01J 37/0244: {Coatings comprising several layers} - B01J 37/0248: {Coatings comprising impregnated particles} - F01N 3/20: specially adapted for catalytic conversion (F01N3/22 takes precedence) - B01D 53/9477: {with catalysts positioned on separate bricks, e.g. exhaust systems} - B01D 2251/2062: Ammonia - B01D 2255/1023: Palladium - B01D 2255/20707: Titanium - B01D 2255/20723: Vanadium - B01D 2255/20776: Tungsten - B01D 2255/2092: Aluminium - B01D 2255/9022: Two layers - B01D 2255/9032: Two zones - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - F01N: GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES (arrangements in connection with gas exhaust of propulsion units in vehicles B60K13/00; combustion-air intake silencers specially adapted for, or arranged on, internal-combustion engines F02M35/00; protecting against, or damping, noise in general G10K11/16) ## 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. ## Claims ### Claim 1 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 noble metal catalyst layer is in physical contact with the vanadium catalyst layer. ### Claim 2 (depends on 1) The catalyst article of claim 1, wherein said noble metal catalyst layer is a coating applied to an inert substrate selected from the group consisting of honeycomb flow-through monoliths, honeycomb wall-flow monoliths, and corrugated metal plates, and wherein said vanadium catalyst layer is a coating applied to said inert substrate. ### Claim 3 (depends on 2) The catalyst article of claim 2, wherein said noble metal catalyst layer is a first layer and said vanadium catalyst layer is a second layer. ### Claim 4 (depends on 3) The catalytic article of claim 3, wherein said first layer is substantially free of vanadium and said second layer is substantially free of noble metals. ### Claim 5 (depends on 4) The catalytic article of claim 4, wherein aid article is calcined. ### Claim 6 (depends on 4) The catalyst article of claim 4, wherein said second layer comprises vanadia pre-fixed to a titania support, wherein said vanadia is present in an amount of about 0.1-10 weight percent based on the weight of the titania. ### Claim 7 (depends on 6) The catalyst article of claim 6, wherein said second layer further comprises an oxide of tungsten. ### Claim 8 (depends on 6) The catalyst article of claim 6, wherein said first layer comprises one or more platinum group metals selected from platinum and palladium on an alumina support, wherein said platinum group metal is present in an amount of about 0.05-0.50 weight percent based on the weight of the alumina support. ### Claim 9 (depends on 3) The catalyst article of claim 3, wherein said second layer is applied over at least a portion of said first layer. ### Claim 10 (depends on 3) The catalyst article of claim 3, wherein said inert substrate is a flow-through honeycomb brick. ### Claim 11 (depends on 10) The catalyst article of claim 10, further comprising a selective catalytic reduction (SCR) catalyst disposed on or in said flow-through brick upstream of said first and second layers. ### Claim 12 (depends on 3) The catalyst article of claim 3, wherein said inert substrate is a corrugated metal plate. ### Claim 13 (depends on 3) The catalyst article of claim 3, wherein said inert substrate is a wall-flow honeycomb filter. ### Claim 14 (depends on 1) The catalyst article of claim 1, wherein said second catalyst layer is an extruded substrate and said first catalyst layer is a coating on said extruded substrate. ### Claim 15 A method for preparing a catalyst article comprising: a. loading vanadium onto a refractory metal oxide support; b. subsequent to step (a), calcining the vanadium loaded refractory metal oxide support to form a prefixed catalyst; c. coating an inert substrate with supported noble metal catalyst to form a first layer; and d. coating said inert substrate with said prefixed catalyst to form a second layer. ### Claim 16 (depends on 15) The method of claim 15, wherein said inert substrate containing said first layer and said second layer is calcined at a temperature of about 400-600° C. for about 1-10 hours. ### Claim 17 (depends on 16) The method of claim 16, wherein said first layer is substantially free of vanadium and said second layer is substantially free of noble metals. ### Claim 18 (depends on 15) The method of claim 15, wherein said first layer comprises vanadia on a titania support and said second layer comprises at least one noble metal selected from platinum and palladium supported on alumina. ### Claim 19 (depends on 1) A method for treating an emission gas comprising: a. contacting a emission gas derived combusting hydrocarbons in a stoichiometric excess of oxygen, wherein the emission gas contains ammonia, with a catalyst article according to claim 1; and b. oxidizing a least a portion of said ammonia to form N2 and/or NOx. ### Claim 20 (depends on 15) The method of claim 15, further comprising an upstream selective catalytic reduction of NOx process. ### Claim 21 (depends on 1) A system for treating an emission gas comprising an SCR catalyst and an ammonia slip catalyst according to claim 1.