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US4791091A Expired / Lapsed US ⏱️ 0.0 years remaining

Catalyst for treatment of exhaust gases from internal combustion engines and method of manufacturing the catalyst

Assignee: Umicore Autocat USA Inc
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Filing: 1987-09-30
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Granted: 1988-12-13
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Expires: 2007-09-30
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Abstract

Abstract This invention relates to a catalytic composite for treating an exhaust gas comprising a support which is a refractory inorganic oxide having dispersed thereon lanthanum, at least one other rare earth component and at least one noble metal component selected from the group consisting of platinum, palladium, rhodium, ruthenium and iridium. An essential feature of said catalytic composite is that the lanthanum be present as crystalline particles of lanthanum oxide which have an average crystallite size of less than about 25 Angstroms. The support may be selected from the group consisting of alumina, silica, titania, zirconia, aluminosilicates and mixtures thereof with alumina being preferred. This invention also relates to a method of manufacturing said catalytic composite. In particular, an important feature of said method of manufacturing is the dispersion of lanthanum oxide onto said refractory inorganic oxide support.

Inventors

  • 👤 Maureen L. Bricker
  • 👤 R. Joe Lawson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 06:45
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/945; B01J; B01J23/00; B01J23/10; B01J23/38; B01J23/54; B01J23/56; B01J23/63; B01J37/00; B01J37/02; B01J37/024; B01D2255/00; B01D2255/20; B01D2255/206; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 119 words
A catalytic composite for treating an exhaust gas comprising a support which is a refractory inorganic oxide selected from the group consisting of alumina, silica, titania, zirconia, alumino-silicates and mixtures thereof, having dispersed thereon lanthanum oxide, the lanthanum oxide being dispersed on said support by the method of commingling a solution of a lanthanum salt with a hydrosol of the metal precursor of said support, forming particles from said lanthanum containing hydrosol, calcining said particles to form a particulate support containing lanthanum oxide, having an average crystallite size of less than 25 Angstroms, at least one other rare earth oxide and at least one noble metal component selected from the group consisting of platinum, palladium, rhodium, ruthenium and iridium.
Claim 2
Dependent Claim 119 words
A catalytic composite for treating an exhaust gas comprising a support which is a refractory inorganic oxide selected from the group consisting of alumina, silica, titania, zirconia, alumino-silicates and mixtures thereof, having dispersed thereon lanthanum oxide, the lanthanum oxide being dispersed on said support by the method of commingling a solution of a lanthanum salt with a hydrosol of the metal precursor of said support, forming particles from said lanthanum containing hydrosol, calcining said particles to form a particulate support containing lanthanum oxide, having an average crystallite size of less than 25 Angstroms, at least one other rare earth oxide and at least one noble metal component selected from the group consisting of platinum, palladium, rhodium, ruthenium and iridium.
Claim 3
Dependent Claim 15 words
The catalytic composite of claim 1 where said support is in the shape of pellets.
Claim 4
Dependent Claim 19 words
The catalytic composite of claim 1 where said support is deposited on a metallic or ceramic monolithic honeycomb carrier.
Claim 5
Dependent Claim 11 words
The catalytic composite of claim 1 where said support is alumina.
Claim 6
Dependent Claim 56 words
The catalytic composite of claim 3 where said noble metal component is platinum, palladium or a mixture thereof, each metal present in a concentration in the range of from about 0.1 to about 4 weight percent of said support and optionally rhodium in a concentration of about 0.01 to about 2 weight percent of said support.
Claim 7
Dependent Claim 16 words
The catalytic composite of claim 5 where the metals are a mixture of platinum and rhodium.
Claim 8
Dependent Claim 16 words
The catalytic composite of claim 5 where the metals are a mixture of palladium and rhodium.
Claim 9
Dependent Claim 17 words
The catalytic composite of claim 5 where the metals are a mixture of platinum, palladium and rnodium.
Claim 10
Dependent Claim 26 words
The catalytic composite of claim 1 where said lanthanum oxide is present in a concentration of about 0.5 to about 15 wt. percent of said support.
Claim 11
Dependent Claim 31 words
The catalytic composite of claim 1 where said rare earth oxide is cerium oxide which is present in a concentration of about 5 to about 35 weight percent of said support.
Claim 12
Independent Claim 144 words
A method of manufacturing a catalytic composite comprising coating a metallic or ceramic solid honeycomb carrier with a support, which is a refractory inorganic oxide, having dispersed thereon lanthanum oxide and at least one other rare earth oxide, the lanthanum oxide being dispersed on said support by commingling a solution of a lanthanum salt with a hydrosol of the metal percursor of said support, forming particles from said lanthanum containing hydrosol, calcining said particles to form a particulate support containing lanthanum oxide, and grinding said calcined particles to yield a powder of said support containing lanthanum oxide having an average crystallite size of less than 25 Angstroms, calcining the resultant coated honeycomb carrier, dispersing at least one noble metal component selected from the group consisting of platinum, palladium, rhodium, ruthenium, and iridium onto said coated honeycomb carrier, calcining and recovering the resultant catalytic composite.
Claim 13
Independent Claim 144 words
A method of manufacturing a catalytic composite comprising coating a metallic or ceramic solid honeycomb carrier with a support, which is a refractory inorganic oxide, having dispersed thereon lanthanum oxide and at least one other rare earth oxide, the lanthanum oxide being dispersed on said support by commingling a solution of a lanthanum salt with a hydrosol of the metal percursor of said support, forming particles from said lanthanum containing hydrosol, calcining said particles to form a particulate support containing lanthanum oxide, and grinding said calcined particles to yield a powder of said support containing lanthanum oxide having an average crystallite size of less than 25 Angstroms, calcining the resultant coated honeycomb carrier, dispersing at least one noble metal component selected from the group consisting of platinum, palladium, rhodium, ruthenium, and iridium onto said coated honeycomb carrier, calcining and recovering the resultant catalytic composite.
Claim 14
Dependent Claim 10 words
The method of claim 11 where said particles are spheres.
Claim 15
Dependent Claim 10 words
The method of claim 11 where said support is alumina.
Claim 16
Dependent Claim 49 words
The method of claim 11 where the noble metal component is platinum, palladium or a mixture thereof present in a concentration from about 0.1 to about 4 weight percent of said support and optionally rhodium in a concentration of about 0.01 to about 2 weight percent of said support.
Claim 17
Dependent Claim 15 words
The method of claim 14 where the metals are a mixture of platinum and rhodium.
Claim 18
Dependent Claim 15 words
The method of claim 14 where the metals are a mixture of palladium and rhodium.
Claim 19
Dependent Claim 16 words
The method of claim 14 where the metals are a mixture of platinum, palladium and rhodium.
Claim 20
Dependent Claim 29 words
The method of claim 11 where the lanthanum oxide dispersed on said support is present in a concentration of about 0.5 to about 15 weight percent of said support.
Claim 21
Dependent Claim 34 words
The method of claim 11 where said rare earth oxide dispersed on said support is cerium oxide which is present in a concentration from about 5 to about 35 weight percent of said support.
Claim 22
Dependent Claim 23 words
The catalytic composite of claim 1 where said catalytic composite is effective at treating exhaust gases after exposure to temperatures of 760° C.

References Cited (Backward Citations)

US2620314A Cited
US3767453A Cited
US3873469A Cited
US4170573A Cited
US4528279A Cited
US4591580A Cited
US4619909A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-12-13 1992-06-13 1992-12-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-12-13 1996-06-13 1996-12-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-12-13 2000-06-13 2000-12-13 $7700.00 Window Closed / Lapsed

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