Ultrasound-assisted method for producing an SCR catalytic converter

Patent metadata

Field	Value
Publication number	US-11400443-B2
Application number	US-201916962406-A
Country	US
Kind code	B2
Filing date	Jan 16, 2019
Priority date	Jan 16, 2018
Publication date	Aug 2, 2022
Grant date	Aug 2, 2022

Abstract

The present invention relates to a method for producing automobile exhaust gas catalytic converters, to the catalytic converters as such and to the use thereof. In particular, the method comprises a step which results in a smaller particle size of the catalytically active material used.

First claim

The invention claimed is:

1. A method for producing a catalytic device containing a zeolite or zeotype for the aftertreatment of exhaust gases of a car engine, comprising: supplying onto and/or into a support a coating having the zeolite or zeotype, with the zeolite or zeotype having been treated with ultrasound in such a way that the particle size of the zeolite or zeotype is reduced to less than 20 μm (d50).

2. The method according to claim 1 , wherein the zeolite or zeotype is derived from structure types selected from the group consisting of the CHA, LEV, AEI, AFX, AFI, or KFI framework, or a mixture thereof.

3. The method according to claim 1 , wherein the zeolite or zeotype is exchanged with iron and/or copper ions.

4. The method according to claim 1 , wherein the coating comprises a binder selected from the group consisting of aluminum oxide, titanium dioxide, zirconium dioxide, silicon dioxide, or mixtures thereof.

5. The method according to claim 1 , wherein the support is a wall-flow filter.

6. The method according to claim 1 , wherein the particle size (d99) is below 7 μm.

7. The method according to claim 1 , wherein the supplied coating has zeolite or zeotype that has been subjected to an ultrasound with an amplitude of 5 to 100 μm.

8. The method according to claim 1 , wherein the supplied coating has zeolite or zeotype that has been subjected to an ultrasound with a power of 500 to 50000 watts.

9. The method according to claim 1 , wherein the coating is subjected to a pre-drying step after the coating of the support.

10. A catalytic device for the aftertreatment of exhaust gases of a car engine, produced according to claim 1 .

11. The catalytic device according to claim 10 , wherein the support is a wall-flow filter.

12. The catalytic device according to claim 11 , wherein the support has a loading with the coating of 30 to 200 g/l.

13. A method for the after-treatment of exhaust gases of a car engine comprising placing the exhaust gases in contact with the catalytic device according to claim 10 .

14. The method according to claim 13 , wherein the exhaust gases are exhaust gases of a lean burning car engine.

15. The method according to claim 13 , wherein the catalytic device is a catalytic device for the selective reduction of nitrogen oxides by ammonia.

16. A method for producing a catalytic device containing a zeolite or zeotype for the aftertreatment of exhaust gases of a car engine, comprising:
treating the zeolite or zeotype with a sonotrode in such a way that the particle size thereof is reduced to less than 20 μm (d50); and
providing a coating that contains the sonotrode treated zeolite or zeotype onto and/or into a support.

17. A method for producing a catalytic device containing a zeolite or zeotype for the aftertreatment of exhaust gases of a car engine, comprising:
treating the zeolite or zeotype with ultrasound in such a way that the particle size thereof is reduced to less than 20 μm (d50); and
providing a coating that contains the ultrasound treated zeolite or zeotype onto and/or into a support.

18. A catalytic device for the aftertreatment of exhaust gases of a car engine, produced according to claim 17 .

19. The catalytic device according to claim 18 wherein the zeolite or zeotype is a small-pore zeolite with ion exchanged iron and/or copper.

20. A method for the after-treatment of exhaust gases of a car engine comprising placing the exhaust gases in contact with the catalytic device according to claim 18 as to cause an SCR reaction.

Assignees

• Umicore Ag & Co Kg

Inventors

• Barth Benjamin
• Foerster Martin
• Schonert Morten

Classifications

• B01J35/56

  Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional [3D] monoliths · CPC title

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title

• B01J35/40

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

• F01N3/2066

  Selective catalytic reduction [SCR] · CPC title

• B01J37/343 Primary

  of ultrasonic wave energy · CPC title