# US 9,751,080 B2 · PGM catalyst for treating exhaust gas

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,751,080 B2
- Document ID: US9751080B2
- Status: Granted
- Kind: B2
- Application number: 14/685,793
- Filed: 2015-04-14
- Published: 2015-08-06
- Granted: 2017-09-05
- Earliest claimed: 2011-06-05
- Assignees: Johnson Matthey Public Limited Company
- Applicants: Johnson Matthey Public Limited Company
- Inventors: Joseph Michael Fedeyko; Hai-Ying Chen; Paul Joseph Andersen
- Web page: https://patentgrep.com/patent/US9751080B2

## CPC

- B01J 29/068: Noble metals
- B01D 53/56: Nitrogen oxides (B01D53/60 takes precedence)
- B01D 53/58: Ammonia
- B01D 53/62: Carbon oxides
- B01D 53/9418: {for removing nitrogen oxides by selective catalytic reduction [SCR] using a reducing agent in a lean exhaust gas}
- B01D 53/9431: {Processes characterised by a specific device}
- B01D 53/944: {Simultaneously removing carbon monoxide, hydrocarbons or carbon making use of oxidation catalysts (three-way-catalysts [TWC] B01D53/9445)}
- B01J 29/7015: {CHA-type, e.g. Chabazite, LZ-218}
- B01J 29/74: Noble metals
- B01J 29/743: {CHA-type, e.g. Chabazite, LZ-218}
- B01J 29/85: Silicoaluminophosphates [SAPO compounds]
- B01J 29/87: Gallosilicates; Aluminogallosilicates; Galloborosilicates {(B01J29/005 takes precedence)}
- B01J 35/19: {Catalysts containing parts with different compositions}
- B01J 35/40: characterised by dimensions, e.g. grain size (in a colloidal state B01J35/23; crystallite size B01J35/77)
- B01J 35/45: Nanoparticles
- B01J 35/56: Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional [3D] monoliths
- B01J 35/58: Fabrics or filaments
- B01J 35/77: Compounds characterised by their crystallite size
- B01J 37/0246: {Coatings comprising a zeolite}
- B01D 53/9477: {with catalysts positioned on separate bricks, e.g. exhaust systems}
- B01D 2255/1021: Platinum
- B01D 2255/50: Zeolites
- B01D 2255/9155: Wall flow filters
- B01D 2255/9205: Porosity
- B01J 23/40: of the platinum group metals
- B01J 29/78: containing arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
- B01J 29/783: {CHA-type, e.g. Chabazite, LZ-218}
- B01J 2229/183: in framework positions
- B01J 2229/186: not in framework positions
- B01J 2229/42: Addition of matrix or binder particles
- 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)
- Y02C: CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
- Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION

## Abstract

Provided are catalysts comprising a small pore molecular sieve embedded with PGM and methods for treating lean burn exhaust gas using the same.

## Claims

### Claim 1

A catalyst article comprising:
a. a substrate; and
b. a PGM catalyst disposed on the substrate in a discrete outlet zone, said catalyst comprising
i. aluminosilicate molecular sieve crystals having surfaces and porous networks, a mean crystalline size of about 0.01 to about 10 microns, a framework selected from CHA, RHO, LEV, AEI, ANA, LTA, DDR, PAU, UEI, and SOD, a silica-to-alumina ratio of about 8 to about 150, and an alkali content of no more than about 5 weight percent based on the total weight of the molecular sieve crystals; and
ii. 0.1 to 5 weight percent palladium based on the total weight of the molecular sieve crystals, wherein a majority amount of said palladium is disposed in said porous networks relative to said surfaces, and
c. an SCR catalyst disposed on the substrate in a discrete inlet zone, said SCR catalyst having either a molecular sieve promoted with iron and/or copper or vanadium on an alumina support.

### Claim 2 (depends on 1)

The catalyst article of claim 1, wherein said substrate is a honeycomb monolith.

### Claim 3 (depends on 1)

The catalyst article of claim 1, wherein said substrate is a wall-flow filter.

### Claim 4 (depends on 1)

The catalyst article of claim 1, wherein said substrate is a flow-through monolith.

### Claim 5 (depends on 1)

The catalyst article of claim 1, wherein the PGM catalyst has a CHA framework.

### Claim 6 (depends on 1)

The catalyst article of claim 1, wherein the PGM catalyst has an AEI framework.

### Claim 7 (depends on 1)

The catalyst article of claim 1, wherein the PGM catalyst has an LTA framework.

### Claim 8 (depends on 1)

The catalyst article of claim 1, wherein the SCR catalyst has a CHA framework.

### Claim 9 (depends on 1)

The catalyst article of claim 1, wherein the SCR catalyst has vanadium on an alumina support.

### Claim 10 (depends on 1)

The catalyst article of claim 1, wherein the inlet and outlet zones are adjacent to each other.

### Claim 11 (depends on 1)

The catalyst article of claim 1, wherein the inlet zone is on the inlet side of the flow-through substrate and outlet zone is on the outlet side of the flow-through substrate.

### Claim 12 (depends on 1)

A method for treating emissions comprising:
a. contacting a lean burn exhaust stream containing NOx and ammonia with a catalyst article according to claim 1 at a temperature of about 150° C. to about 650° C.; and
b. reducing at least a portion of said NOx to N2 and H2O at a temperature of about 150° C. to about 250° C. and oxidizing at least a portion of said ammonia at a temperature of about 300° C. to about 650° C.

### Claim 13 (depends on 12)

The method of claim 12, wherein said reducing has a selectivity for N2 of at least about 90% at a temperature of about 150° C. to about 250° C.

### Claim 14 (depends on 12)

The method of claim 12, wherein said reducing has a N2O selectivity of less than about 10% at a temperature of about 150° C. to about 650° C.

### Claim 15 (depends on 12)

The method of claim 12, wherein said oxidizing has a conversion of at least about 95% at a temperature of about 350° C. to about 650° C.

### Claim 16 (depends on 1)

A method for treating emissions comprising:
a. contacting a lean burn exhaust stream containing CO and NO with a catalyst article according to claim 1;
b. oxidizing at least one of said CO and NO to form CO2 and NO2, respectively, wherein said oxidizing NO to NO2 results in an exhaust gas stream having an NO:NO2 ratio of from about 4:1 to about 1:3 by volume.

### Claim 17

A system for treating exhaust gas comprising:
a. a reductant source;
b. an upstream SCR catalyst; and
c. a downstream PGM catalyst comprising
i. aluminosilicate molecular sieve crystals having surfaces and porous networks, a mean crystalline size of about 0.01 to about 10 microns, a framework selected from CHA, RHO, LEV, AEI, ANA, LTA, DDR, PAU, UEI, and SOD, a silica-to-alumina ratio of about 8 to about 150, and an alkali content of no more than about 5 weight percent based on the total weight of the molecular sieve crystals; and
d. 0.1 to 5 weight percent palladium based on the total weight of the molecular sieve crystals, wherein a majority amount of said palladium is disposed in said porous networks relative to said surfaces;
wherein said SCR catalyst and said PGM catalyst are disposed on separate substrates;
said reductant source, upstream SCR catalyst, and downstream catalyst are in fluid communication with each other and are arranged so that an exhaust gas stream flowing through the system contacts the reductant source prior to the upstream SCR catalyst and contacts the SCR catalyst prior to the downstream SCR catalyst.

### Claim 18 (depends on 17)

The system of claim 17, wherein said reductant source is a NOx absorber catalyst.

### Claim 19 (depends on 17)

The system of claim 17, wherein said upstream SCR catalyst has a NOx conversion efficiency greater than that of said downstream catalyst at a temperature of about 350° C. to about 650° C. and said downstream catalyst has a NOx conversion efficiency greater than that of said upstream SCR catalyst at a temperature of about 150° C. to about 250° C.

### Claim 20 (depends on 17)

The system of claim 17, wherein said downstream catalyst selectively reduces NOx when contacting said exhaust gas stream at a temperature of about 150° C. to about 250° C. and oxidizes the nitrogenous reductant when contacting said exhaust gas stream at a temperature of about 350° C. to about 650° C.