Nitrous oxide removal catalysts for exhaust systems

Patent metadata

Field	Value
Publication number	US-11149610-B2
Application number	US-202016838751-A
Country	US
Kind code	B2
Filing date	Apr 2, 2020
Priority date	Dec 8, 2014
Publication date	Oct 19, 2021
Grant date	Oct 19, 2021

Abstract

A nitrous oxide (N2O) removal catalyst composite is provided, comprising a N2O removal catalytic material on a substrate, the catalytic material comprising a rhodium (Rh) component supported on a ceria-based support, wherein the catalyst composite has a H2-consumption peak of about 100° C. or less as measured by hydrogen temperature-programmed reduction (H2-TPR). Methods of making and using the same are also provided.

First claim

What is claimed is:

1. A method of making a nitrous oxide (N 2 O) removal catalyst composite, the method comprising:
depositing a rhodium precursor onto a fresh ceria-based support having a pore volume of at least about 0.20 cm 3 /g and forming a washcoat therefrom;
coating a substrate comprising a flow-through monolith or a wall-flow filter with the washcoat to form a coated substrate; and
calcining the coated substrate in air at a temperature between about 600° C. and about 800° C. for at least 10 hours.

2. The method of claim 1 , wherein the calcining step is carried out under conditions of 750° C. for 20 hours with 10 weight % water in air.

3. The method of claim 1 , further comprising:
calcining the fresh ceria-based support at about 600° C. to about 800° C. before the depositing step.

4. The method of claim 1 , wherein the temperature is 750° C.

5. The method of claim 1 , wherein the calcining step is carried out for about 10 to about 30 hours.

6. The method of claim 1 , wherein the calcining step is carried out for about 20 hours.

Assignees

• Basf Corp

Inventors

• Li Yuejin
• Zheng Xiaolai
• Roth Stanley
• Gerlach Olga
• Sundermann Andreas

Classifications

• B01J35/40

  characterised by dimensions, e.g. grain size (in a colloidal state B01J35/23; crystallite size B01J35/77) · CPC title

• B01J35/45

  Nanoparticles · CPC title

• B01J35/77

  Compounds characterised by their crystallite size · CPC title

• B01J37/0244 Primary

  Coatings comprising several layers · CPC title

• B01J2235/15

  X-ray diffraction · CPC title