# US 2019/0168198 A1 · Ammonia slip catalyst designed to be first in an scr system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0168198 A1 - Document ID: US20190168198A1 - Status: Published application - Kind: A1 - Application number: 16/272,002 - Filed: 2019-02-11 - Published: 2019-06-06 - Earliest claimed: 2015-06-18 - Assignees: Johnson Matthey Public Limited Company - Applicants: Johnson Matthey Public Limited Company - Inventors: Mikael Larsson; David Micallef - Web page: https://patentgrep.com/patent/US20190168198A1 ## CPC - B01J 29/763: {CHA-type, e.g. Chabazite, LZ-218} - 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} - B01D 53/9472: {in different zones} - B01J 21/04: Alumina - 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 - B01D 2255/1021: Platinum - B01D 2255/1023: Palladium - B01D 2255/2092: Aluminium - B01D 2255/50: Zeolites - B01D 2255/9037: More than three zones - B01D 2255/915: Catalyst supported on particulate filters - Y02A 50/20: Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters - Y02C 20/10: of nitrous oxide (N2O) - Y02T 10/12: Improving ICE efficiencies - 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) - Y02A: TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE - Y02C: CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG] - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract Catalyst articles having an ammonia slip catalyst (ASC) comprising a blend of platinum on a support with low ammonia storage and a first SCR catalyst, and a second catalyst, such as a diesel oxidation catalyst, a diesel exotherm catalyst (DEC), a NOx absorber, a selective catalytic reduction/passive NOx adsorber (SCR/PNA), a cold-start catalyst (CSC) or a three-way catalyst (TWC) are disclosed. The catalyst articles can also contain one or two additional SCR catalysts. The catalysts can be present in one of various configurations. The catalytic articles are useful for selective catalytic reduction (SCR) of NOx in exhaust gases and in reducing the amount of ammonia slip. Methods of using the catalytic articles in an SCR process, where the amount of ammonia slip is reduced, are also described. ## Claims ### Claim 1 A method of treating an exhaust gas, comprising contacting the exhaust gas with a catalyst article comprising a substrate comprising an inlet end and an outlet end, a first zone and a second zone, where the first zone comprises an ammonia slip catalyst (ASC) comprising a platinum group metal and a first SCR catalyst comprising a metal exchange molecular sieve, vanadium or a base metal, and the second zone comprises a second catalyst selected from the group consisting of a diesel oxidation catalyst (DOC), a diesel exotherm catalyst (DEC), a catalyzed soot filter (CSF), a NOx absorber, a selective catalytic reduction/passive NOx adsorber (SCR/PNA), a cold-start catalyst (CSC) or a three-way catalyst (TWC), where the first zone is located upstream of the gas flow relative to the second zone. ### Claim 2 (depends on 1) The method of claim 1, where the first zone and the second zone are located on the same substrate and the first zone is located on the inlet side of the substrate and the second zone is located on the outlet side of the substrate. ### Claim 3 (depends on 1) The method of claim 1, further comprising a second substrate, where the first zone is located on a first substrate and the second zone is located on the second substrate and the first substrate is located upstream of the second substrate. ### Claim 4 (depends on 1) The method of claim 1, where the ammonia slip catalyst comprises a bottom layer comprising a platinum group metal and a top layer comprising the first SCR catalyst located over the bottom layer. ### Claim 5 (depends on 1) The method of claim 1, where the ammonia slip catalyst comprises a blend of a platinum group metal on a support with low ammonia storage and a first SCR catalyst. ### Claim 6 (depends on 1) The method of claim 1, where the second zone comprises a blend of a diesel oxidation catalyst and a second SCR catalyst. ### Claim 7 (depends on 1) The method of claim 1, further comprising a second SCR catalyst, where the second SCR catalyst is located between the ammonia slip catalyst and the second catalyst. ### Claim 8 (depends on 1) The method of claim 1, where the platinum group metal comprises platinum, palladium or a combination of platinum and palladium. ### Claim 9 (depends on 1) The method of claim 1, where the platinum group metal is on a support with low ammonia storage. ### Claim 10 (depends on 1) The method of claim 1, where platinum is present from at least one of: (a) 0.01-0.3 wt. %, (b) 0.03-0.2 wt. %, (c) 0.05-0.17 wt. %, and (d) 0.07-0.15 wt. %, inclusive, relative to the weight of a support of platinum+the weight of platinum+the weight of the first SCR catalyst in the blend. ### Claim 11 (depends on 7) The method of claim 7, where the second SCR catalyst is a base metal, an oxide of a base metal, a molecular sieve, a metal exchanged molecular sieve or a mixture thereof. ### Claim 12 (depends on 11) The method of claim 11, where the molecular sieve or the metal exchanged molecular sieve is small pore, medium pore, large pore or a mixture thereof. ### Claim 13 (depends on 1) The method of claim 1, where the article comprises only one ammonia slip catalyst (ASC) and either (a) the second zone does not comprise a diesel oxidation catalyst (DOC) or (b) the DOC is not located adjacent to, and downstream of, the ammonia slip catalyst. ### Claim 14 (depends on 1) The method of claim 1, further comprising a third zone comprising an ASC catalyst, where the third zone is located between the first zone and the second zone. ### Claim 15 (depends on 14) The method of claim 14, where the PGM in the first zone comprises palladium in an amount of about 1 g/ft3 to about 20 g/ft3. ### Claim 16 An exhaust system comprising a. a catalyst article comprising a substrate comprising an inlet end and an outlet end, a first zone and a second zone, where the first zone comprises an ammonia slip catalyst (ASC) comprising a platinum group metal and a first SCR catalyst comprising a metal exchange molecular sieve, vanadium or a base metal, and the second zone comprises a second catalyst selected from the group consisting of a diesel oxidation catalyst (DOC), a diesel exotherm catalyst (DEC), a catalyzed soot filter (CSF), a NOx absorber, a selective catalytic reduction/passive NOx adsorber (SCR/PNA), a cold-start catalyst (CSC) or a three-way catalyst (TWC), where the first zone is located upstream of the gas flow relative to the second zone; and b. a means of introducing NH3 into the exhaust gas or forming NH3 in the exhaust gas. ### Claim 17 (depends on 16) The exhaust system of claim 16, further comprising a catalysed soot filter (CSF). ### Claim 18 (depends on 17) The exhaust system of claim 17, where the catalysed soot filter comprises a PGM loading from about 5 g/ft3 to about 20 g/ft3 in the inlet side of the filter.