IP Library › Granted Patent US 12,359,595
Granted Patent B2
US 12,359,595 · App. 17/292,080 · Granted Jul 15, 2025

Particle filter with a plurality of coatings

Inventors: Martin Foerster (Büdingen, DE); Benjamin Barth (Alzenau, DE); Manuel Gensch (Aschaffenburg, DE); Jan Schoenhaber (Darmstadt, DE)
Assignee: UMICORE AG & CO, KG
F01N3/022B01D46/2429B01D46/24492B01D46/249B01D53/9472B01J35/31B01J35/40B01J35/56B01J35/64B01J37/0221F01N3/035F01N3/101F01N3/2803B01D46/2482B01D53/9431B01D53/9454B01D2255/10B01D2255/9032B01D2255/9155B01D2279/30C04B41/4545F01N2370/02
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Quick Facts
Patent No.
US 12,359,595
App. No.
17/292,080
Granted
Jul 15, 2025
Kind
B2
Abstract

The invention relates to a wall-flow filter, to a method for the production and the use of the filter for reducing harmful exhaust gases of an internal combustion engine. The wall-flow filter was produced by exposing the filter at least twice successively to a powder-gas aerosol.

Claims (75)

1. Wall-flow filter for reducing the harmful substances in the exhaust gas of an internal combustion engine,

characterized in that

on its inlet side, the dry filter has been exposed at least twice successively to different dry powder-gas-aerosols, each of which has at least one high-melting metal compound.

2. Wall-flow filter according to claim 1 ,

characterized in that

the filter was catalytically coated prior to being exposed to the first powder-gas-aerosol.

3. Wall-flow filter according to claim 1 ,

characterized in that

during the first exposure, the powder precipitates in the pores of the filter walls and fills them at least up to the inlet surface and thereby does not form a cohesive layer on the walls of the filter over the entire length of the filter.

4. Wall-flow filter according to claim 1 ,

characterized in that

the total amount of powder remaining in the filter is below 100 g/l.

5. Wall-flow filter according to claim 1 ,

characterized in that

the final powder coating has an increasing concentration gradient over the length of the filter from the inlet side to the outlet side.

6. Wall-flow filter according to claim 5 ,

characterized in that

the concentration gradient is created such that in a region near the inlet side and in a region in the center of the filter, less than 40% of the wall surface of the inlet channel are respectively coated with powder, while in a region near the outlet side, more than 40% of the wall surface of the inlet channel are coated with powder.

7. Wall-flow filter according to claim 1 ,

characterized in that

when filter substrates with square channels are used, the powder coating in the corners of the channels is thicker than in the corresponding center of the inlet surface.

8. Wall-flow filter according to claim 1 ,

characterized in that

the aerosols are a mixture of air and the powder of the at least one high-melting metal compound, with the at least one high-melting metal compound being selected from the group consisting of a metal oxide, metal sulfate, metal phosphate, metal carbonate, or metal hydroxide powder, or mixtures thereof.

9. Wall-flow filter according to claim 1 ,

characterized in that

at least one of the powders is catalytically active with regard to reducing the harmful substances in the exhaust gas of an internal combustion engine.

10. Wall-flow filter according to claim 1 ,

characterized in that

the first powder has a mean particle diameter (d50) of > 1/10 and <3 of the mean pore diameter (d50) of the filter.

11. Wall-flow filter according to claim 1 ,

characterized in that

the first powder has a tamped density of <200 kg/m 3 .

12. Wall-flow filter according to claim 1 ,

characterized in that

the second or the further powders have a mean particle diameter (d50)< 1/10 of the mean pore diameter.

13. Wall-flow filter according to claim 1 ,

characterized in that

the second or the further powders have a tamped density of between 50 kg/m 3 and 1200 kg/m 3 .

14. Wall-flow filter according to claim 1 ,

characterized in that

the filter has a catalytically active powder zone in the last third of the filter in the inlet channel.

15. Method for producing a wall-flow filter according to claim 1 for reducing the harmful substances in the exhaust gas of an internal combustion engine, wherein a dry filter is exposed on its inlet surface at least twice successively to different dry powder-gas-aerosols, each having at least one high-melting metal compound,

characterized in that

the powders are dispersed one after the other in the gas, then guided into a gas stream, and sucked into the inlet side of the filter without further supply of a gas.

16. Method for producing a wall-flow filter according to claim 15 ,

characterized in that

the aerosols are sucked through the filter at a velocity of 5 m/s to 60 m/s.

17. Method according to claim 15 ,

characterized in that

the dispersion of the powders in the gas is in each case effected by at least one of the following measures:

Dispersion by means of compressed air

Dispersion by ultrasound

Dispersion by sieving

Dispersion by “in-situ milling”

Dispersion by blower

Dispersion by expansion

Dispersion in the fluidized bed.

18. Method according to claim 15 ,

characterized in that

at least one partial gas stream is extracted downstream of the suction device and, before the powder addition, is added to the gas stream which is sucked through the filter.

19. Method according to claim 15 ,

characterized in that

a defined powder distribution over the filter cross section is adjusted by an accelerated flow upstream of the filter.

20. Method according to claim 15 ,

characterized in that

the powders are vortexed before flowing into the filter in such a way that deposits of the powders on the inlet plugs of the wall-flow filter are prevented as much as possible.

21. A method of reducing harmful exhaust gases of an internal combustion engine comprising passing the exhaust gases through the wall-flow filter according to claim 1 for reducing harmful exhaust gases of an internal combustion engine.

22. The method according to claim 21 ,

characterized in that

the filter is used in an exhaust system together with one or more catalytically active aggregates selected from the group consisting of nitrogen oxide storage catalyst, SCR catalyst, three-way catalyst, and diesel oxidation catalyst.

23. Wall-flow filter for reducing the harmful substances in the exhaust gas of an internal combustion engine,

wherein the wall-flow filter has a dry filter substrate and, on the dry filter substrate inlet side, the dry filter substrate has been exposed at least twice successively to different dry powder-gas-aerosols, and wherein a first powder of the different dry powder-gas-aerosols is pyrogenic and has a mean particle diameter (d50) that is greater than a second powder of the different dry powder-gas-aerosols such that the first powder is coarser than the second powder, and wherein the first applied powder is seated in pores of the dry filter substrate and the second, finer dry powder is blocked from passage through the pores by the coarser first powder seated in the pores, and wherein the first powder has no catalytic activity and the second powder has soot ignition catalytic activity.

24. Wall-flow filter according to claim 23 , wherein the finer dry powder coating has an increasing concentration gradient over the length of the filter from the inlet side to the outlet side.

25. Wall-flow filter according to claim 23 , wherein the first powder of the different dry powder-gas-aerosols has a mean particle diameter (d50) of > 1/10 and <3 of the mean pore diameter (d50) of the filter substrate and the second powder of the different dry powder-gas-aerosols has a mean particle diameter (d50)< 1/10 of the mean pore diameter as to provide for the first powder being coarser than the second powder, and the first powder is sized for in-wall receipt in the dry filter substrate and blockage of the finer second powder from passage through the pores of the dry filter substrate.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 30, 2021
From: FOERSTER, MARTIN; BARTH, BENJAMIN; GENSCH, MANUEL; SCHOENHABER, JAN
To: UMICORE AG & CO. KG
Reel/Frame 057326/0794 →
Priority Claims (1)
DE 10 2018 127 957.4 · Nov 8, 2018 · national
Continuity (1)
Related Publication 20210404357A1 · Dec 30, 2021
References Cited (154)
US 108408A · Tilghman · 1870 [cited by applicant]
US 1967235A · Ferkel · 1934 [cited by applicant]
US 2488440A · Schaumann · 1949 [cited by applicant]
US 4609563A · Shimrock et al. · 1986 [cited by applicant]
US 6220791B1 · Hutchins · 2001 [cited by applicant]
US 6478874B1 · Rosynsky et al. · 2002 [cited by applicant]
US 6548105B2 · Kiessling et al. · 2003 [cited by applicant]
US 6875725B2 · Lindner et al. · 2005 [cited by applicant]
US 7306771B2 · Okawara · 2007 [cited by applicant]
US 7985380B2 · Brück · 2011 [cited by applicant]
US 8277880B2 · Sato et al. · 2012 [cited by applicant]
US 8388721B2 · Ishizawa · 2013 [cited by applicant]
US 8454917B2 · Hoyer · 2013 [cited by examiner]
US 8495968B2 · Tsuji et al. · 2013 [cited by applicant]
US 8534221B2 · Tsuji et al. · 2013 [cited by applicant]
US 8632852B2 · Tsuji et al. · 2014 [cited by applicant]
US 8663588B2 · Lindner et al. · 2014 [cited by applicant]
US 8678196B2 · Kaiser et al. · 2014 [cited by applicant]
US 8794178B2 · Mergner et al. · 2014 [cited by applicant]
US 8940259B2 · Brown et al. · 2015 [cited by applicant]
US 9347354B2 · Pfeifer et al. · 2016 [cited by applicant]
US 9517462B2 · Roesch et al. · 2016 [cited by applicant]
US 9745227B2 · Cai et al. · 2017 [cited by applicant]
US 10188975B2 · Fu et al. · 2019 [cited by applicant]
US 10247079B2 · Tabata · 2019 [cited by applicant]
US 10279313B2 · Gabrielsson · 2019 [cited by applicant]
US 10294838B2 · Itoh et al. · 2019 [cited by applicant]
US 11566548B2 · Foerster et al. · 2023 [cited by applicant]
US 20010003351A1 · Chen et al. · 2001 [cited by applicant]
US 20080107806A1 · Mergner et al. · 2008 [cited by applicant]
US 20080317646A1 · Morisaka et al. · 2008 [cited by applicant]
US 20110030346A1 · Neubauer et al. · 2011 [cited by applicant]
US 20110229634A1 · Tsuji et al. · 2011 [cited by applicant]
US 20110229635A1 · Tsuji et al. · 2011 [cited by applicant]
US 20110271658A1 · Hoyer · 2011 [cited by examiner]
US 20130243659A1 · Sutton et al. · 2013 [cited by applicant]
US 20160310935A1 · Sutton et al. · 2016 [cited by applicant]
US 20160375429A1 · Chandler et al. · 2016 [cited by applicant]
US 20170296969A1 · Ohashi et al. · 2017 [cited by applicant]
US 20180298800A1 · Clowes et al. · 2018 [cited by applicant]
US 20190060885A1 · Welsch et al. · 2019 [cited by applicant]
US 20210396167A1 · Foerster et al. · 2021 [cited by applicant]
US 20220325645A1 · Gensch et al. · 2022 [cited by applicant]
US 20230127269A1 · Foerster et al. · 2023 [cited by applicant]
CN 1490500A · 2004 [cited by applicant]
CN 1720093A · 2006 [cited by applicant]
CN 102188857A · 2011 [cited by applicant]
CN 102281946A · 2011 [cited by applicant]
CN 102762827A · 2012 [cited by applicant]
CN 103079683A · 2013 [cited by applicant]
CN 104838099A · 2015 [cited by applicant]
CN 105561685A · 2016 [cited by applicant]
CN 106164429A · 2016 [cited by applicant]
CN 107636271A · 2018 [cited by applicant]
CN 107921367A · 2018 [cited by applicant]
CN 108350777A · 2018 [cited by applicant]
CN 108697980A · 2018 [cited by applicant]
DE 948415C · 1956 [cited by applicant]
DE 952891C · 1956 [cited by applicant]
DE 4225970C1 · 1994 [cited by applicant]
DE 19921409A1 · 2000 [cited by applicant]
DE 102009010711A1 · 2010 [cited by applicant]
DE 102010007499A1 · 2011 [cited by applicant]
DE 102010015364A1 · 2011 [cited by applicant]
EP 1064094B1 · 2002 [cited by applicant]
EP 1181970B1 · 2004 [cited by applicant]
EP 1136462B1 · 2004 [cited by applicant]
EP 1576998A2 · 2005 [cited by applicant]
EP 2388072A1 · 2011 [cited by applicant]
EP 2412419A1 · 2012 [cited by applicant]
EP 2415522A1 · 2012 [cited by applicant]
EP 2502661A2 · 2012 [cited by applicant]
EP 2521618B1 · 2013 [cited by applicant]
EP 1541220B1 · 2014 [cited by applicant]
EP 2727640A1 · 2014 [cited by applicant]
EP 2502662B1 · 2014 [cited by applicant]
EP 2783755A1 · 2014 [cited by applicant]
EP 2576021B1 · 2014 [cited by applicant]
EP 2832962A1 · 2015 [cited by applicant]
EP 2371451B1 · 2016 [cited by applicant]
EP 2371452B1 · 2016 [cited by applicant]
EP 1789190B1 · 2017 [cited by applicant]
JP H01151706A · 1989 [cited by applicant]
JP 2004275814A · 2004 [cited by applicant]
JP 2008215337A · 2008 [cited by applicant]
JP 5378659B2 · 2013 [cited by applicant]
JP 2014205108A · 2014 [cited by applicant]
WO 9947260A1 · 1999 [cited by applicant]
WO 2005016497A1 · 2005 [cited by applicant]
WO 2005022667A2 · 2005 [cited by applicant]
WO 2008000449A2 · 2008 [cited by applicant]
WO 2008113445A1 · 2008 [cited by applicant]
WO 2010015573A2 · 2010 [cited by applicant]
WO 2010097146A1 · 2010 [cited by applicant]
WO 2011151711A1 · 2011 [cited by applicant]
WO 2012030534A1 · 2012 [cited by applicant]
WO 2014087472A1 · 2014 [cited by applicant]
WO 2015049110A1 · 2015 [cited by applicant]
WO 2015121248A1 · 2015 [cited by applicant]
WO 2015143191A1 · 2015 [cited by applicant]
WO 2017056067 · 2017 [cited by applicant]
WO 2017075328A1 · 2017 [cited by applicant]
WO 2018115900A1 · 2018 [cited by applicant]
WO 2018172299A1 · 2018 [cited by applicant]
WO 2019089806A1 · 2019 [cited by applicant]
WO 2020094760A1 · 2020 [cited by applicant]
WO 2020094763A1 · 2020 [cited by applicant]
Non Final Office Action mailed Dec. 9, 2021 in U.S. Appl. No. 17/292,059 (11 pages). [cited by applicant]
Non Final Office Action mailed Jun. 28, 2023 in U.S. Appl. No. 18/069,736 (13 pages). [cited by applicant]
Non Final Office Action mailed Jun. 7, 2023 in U.S. Appl. No. 17/292,068 (8 pages). [cited by applicant]
U.S. Appl. No. 18/069,736, filed Dec. 21, 2022, Foerster et al. [cited by applicant]
Notice of Allowance and Fees Due mailed Oct. 3, 2022 in U.S. Appl. No. 17/292,059 (11 pages). [cited by applicant]
Notice of Allowance and Fees Due mailed Feb. 1, 2023 in U.S. Appl. No. 17/292,068 (9 pages). [cited by applicant]
Translation of Chinese First Office Action mailed Jan. 30, 2023 for Chinese Patent Application No. 201980073214.2 (13 pages). [cited by applicant]
Translation of Chinese First Office Action mailed Feb. 1, 2023 for Chinese U.S. Appl. No. 17/292,059.0 (11 pages). [Family member of U.S. Appl. No. 17/292,059, which has been issued to Applicant as U.S. Pat. No. 11,566,… [cited by applicant]
Office Action and Search Report mailed Sep. 28, 2023 for Chinese Patent Application No. 201980073214.2 (8 pages in Chinese; 8 pages English Translation). [cited by applicant]
U.S. Appl. No. 17/292,059, filed May 7, 2021, Foerster, et al. [cited by applicant]
U.S. Appl. No. 17/292,068, filed May 7, 2021, Foerster, et al. [cited by applicant]
International Preliminary Report on Patentability dated May 11, 2021 for International Patent Application No. PCT/EP2019/080489 (6 pages in German with English Translation). [cited by applicant]
Written Opinion of the International Searching Authority dated Jan. 24, 2020 for International Patent Application No. PCT/EP2019/080489 (5 pages in German with English Translation). [cited by applicant]
International Search Report dated Jan. 24, 2020 for International Patent Application No. PCT/EP2019/080489 (3 pages in German with English Translation). [cited by applicant]
Gutsch, A. et al. Gas-Phase Production of Nanoparticles.KONA. 2002. No. 20. 14 pages. [cited by applicant]
Ulrich, G. Theory of Particle Formation and Growth in Oxide Synthesis Flames. Combustion Science and Technology. 21971. vol. 4. pp. 47-57. [cited by applicant]
Ihalainen, M., et al. Break-Up and bounce of TiO2 agglomerates by impaction. J. In: Aerosol Science and Technology. 2014. vol. 48, No. 1, pp. 31-41. [cited by applicant]
Seipenbusch, M., et al. Interparticle forces in silica nanoparticle agglomerates Journal of Nanoparticle Research. 2010. vol. 12, No. 6, pp. 2037-2044. [cited by applicant]
Gensch, M. Dissertation, Mechanische Stabilität von Nanopartikel—Agglomeraten bei mechanischen Belastungen. 2018. ISBN: 978-3-8440-6110-9, Shaker Verlag. [cited by applicant]
Füchsel, S., et al. Trockene Desagglomeration von Nanopartikelagglomeraten in einer Sichtermühle. [Dry deagglomeration of nanoparticle agglomerates in a classifier mill]. Chemie Ingenieur Technik. 2011, 83, No. 8, pp. 1… [cited by applicant]
Li S., et al. Flame aerosol synthesis of nanostructured materials and functional devices: Processing, modeling, and diagnostics. Progress in Energy and Combustion Science (55). 2016. pp. 1-59. [cited by applicant]
Heck, R., et al., Catalytic Air Pollution Control—Commercial Technology, Wiley. 2002. pp. 86-89. [cited by applicant]
Aerosolgeneratoren Und—Dispergierer. accessed May 7, 2018. http://www.tsi.com/Aerosolgeneratoren-und-dispergierer/. [cited by applicant]
Pyrogenes Siliciumdioxid. Wikipedia. Accessed Nov. 16, 2018. https://de.wikipedia.org/w/index.php?title=Pyrogenes_Siliciumdioxid&oldid=1 82147815. [cited by applicant]
Aerosolgernatoren fur Feststoffe. Accessed May 7, 2018. https://www.palas.de/de/product/aerosolgeneratorssolidparticles. [cited by applicant]
Reindichte. Wikipedia. Accessed Nov. 16, 2018. https://de.wikipedia.org/w/index.php?title=Reindichte&oldid=164022376. [cited by applicant]
Pyrogenes Siliciumdioxid. Wikipedia. accessed Nov. 16, 2018. https://de.wikipedia.org/wiki/Pyrogenes_Siliciumdioxid. [cited by applicant]
Aerosil Fumed Silica and Aeoxide Fumed Alumina for Glossy Photo Inkjet Media. Technical Information 1331. https://www.aerosil.com/product/aerosil/downloads/ti-1331-aerosil-and-aeroxide-for-glossy-photo-inkjet-media-en.p… [cited by applicant]
Fumed silica process.svg. Wikimedia Commons. Accessed Nov. 28, 2016. https://commons.wikimedia.org/w/index.php?title=File:Fumed_silica process.svg&oldid=222460038. [cited by applicant]
Framework type AEI. Database of Zeolite Structures. accessed Apr. 10, 2018. http://europe.iza-structure.org/IZA-SC/framework.php?STC=CHA. [cited by applicant]
Framework type CHA. Database of Zeolite Structures. accessed Apr. 10, 2018. http://europe.iza-structure.org/IZA-SC/framework.php?STC=AEI. [cited by applicant]
ISO 13320: 2009(E). Particle size analysis—Laser diffraction Methods (60 pages). [cited by applicant]
DIN 66133. Jun. 1993, Bestimmung der Porenvolumenverteilung und der spezifischen Oberfläche von Feststoffen durch Quecksilberintrusionv. [Determination of the pore volume distribution and the specific surface area of so… [cited by applicant]
DIN 66134. Feb. 1998, Bestimmung der Porengrößenverteilung und der spezifischen Oberfläche mesoporöser Feststoffe durch Stickstoffsorption Verfahren nach Barrett, Joyner und Halenda (BJH) [Determination of the pore size… [cited by applicant]
Mathis. U., et al., TEM analysis of volatile nanoparticles from particle trap equipped diesel and direct-injection spark-ignition vehicles. Atmospheric Environment. vol. 38. pp. 4347-4355. [cited by applicant]
Albers, P., et al. Kristallin und amorph Sand als Rohstoff. [Crystalline and amorphous sand as a raw material]. Chemie in unserer Zeit, 2016, vol. 50, pp. 162-171 (in German with English translation). [cited by applicant]
Von Karman, T. Ueber den Mechanismus des Widerstandes, den ein bewegter Körper in einer Flüssigkeit erfährt [About the mechanism of resistance a moving body experiences in a liquid] Nachr. Ges. Wiss. Göttingen, Math. Ph… [cited by applicant]
Benard, H. Comptes rendus hebdomadaires des séances de l'Académie des sciences/ publiés . . . par MM. les secrétaires perpétuels. [Weekly reports of the sessions of the Academy of Sciences / published . . . by MM. perpe… [cited by applicant]
Hall, D.E., et al., Measurement of the Number of Siz Distribution of Particles Emitted from a Gasoline Direct Injection Vehicle. SAE. 1999-01-3530. pp. 1-11. [cited by applicant]
Ferkel, H., et al. Edelmetallfreie Nanokatalysatoren Für Dieselpartikelfilter [Non-Metal-Free Nanocatalysts for diesel Particulate Filters]. MTZ—Motortechnische Zeitschrift, 2010, vol. 71, pp. 128-133. In German with En… [cited by applicant]
Hinds, W.C. Aerosol technology: Properties, behavior and measurement of airborne particles. Wiley, 2 [cited by applicant]
Maricq, M.M., et al., Particulate Emissions from a Direct-Injection Spark-Ignition (DISI) Engine. SAE. 1999-01-1530. 1999. pp. 1-9. [cited by applicant]
ISO 11465—Soil Quality—Determination fo dry matter and water content on a mass basis—Gravimetric Method. 1993 (8 pages). [cited by applicant]
Stieß, M. Mechanical Process Engineering—Particle Technology 1, Springer, 3rd edition 2009. Kapitel 2. Kennzeichnungen von Partikeln und dispersen Stoffsystemen [Chapter 2 Identification of particles and disperse Substa… [cited by applicant]
Final Office Action mailed Jun. 28, 2022 in U.S. Appl. No. 17/292,059 (14 pages). [cited by applicant]
Notice of Opposition to a European Patent mailed Apr. 11, 2023 in European Patent Application No. 19801526.5 (16 pages). [Family member of U.S. Appl. No. 17/292,068; now US Pub. 2022/0325645]. [cited by applicant]
Jang, Hee Dong et al. Synthesis of SiO2 nanoparticles from sprayed droplets of tetraethylorthosilicate by the flame spray pyrolysis. Current Applied Physics 6S1. 2006. pp. e110 to e113. [cited by applicant]