US4438219A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alumina catalyst stable at high temperatures
Assignee: Texaco Inc
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Filing: 1981-10-28
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Granted: 1984-03-20
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Expires: 2001-10-28
Abstract
Abstract An alumina catalyst, which has a desired porosity and surface area and is stable at high temperatures is formed by contacting a substrate with an alkali aluminate solution for a period of time sufficient to form an adherent film of hydrated alumina on the substrate, separating the substrate with the adherent film of hydrated alumina from the solution, heating the substrate and alumina film under calcining conditions until an alumina film of desired porosity and surface area is formed, and then contacting the calcined alumina film with a material which stabilizes the alumina during subsequent heating. Optionally, the alumina film can then be further calcined at a temperature higher than that used in the first calcining conditions, preferably at a temperature up to about 1260° C. The stabilizing material can be one of several compounds including those of barium, silcon, and the rare earth metals. Further, dissolving the stabilizing material and a catalytic metal, such as platinum, into a solvent, and contacting this solution with the calcined alumina film produces a substantially even distribution of the catalytic metal on the calcined alumina film.
Inventors
- 👤 John T. Brandenburg
- 👤 John M. Crone, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:35
CPC Classifications
B; B01; B01J; B01J21/00; B01J21/12; B01J21/02; B01J21/04; B01J37/00; B01J37/02; B01J37/0215
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
110 words
A method of preparing a catalytic article comprising the steps of contacting a substrate and aluminum metal with an aqueous solution of an alkali hydroxide, and an alkali aluminate for a period of time sufficient to form an adherent film of alumina on said substrate; separating said substrate with said adherent film of alumina from said solution; then heating said substrate and said film of alumina under calcining conditions until said alumina film develops a desired porosity and surface area; and then contacting said calcined alumina film with a material which ameliorates the reduction in surface area and loss of structural integrity of said calcined alumina film during subsequent heating.
Claim 2
Independent Claim
110 words
A method of preparing a catalytic article comprising the steps of contacting a substrate and aluminum metal with an aqueous solution of an alkali hydroxide, and an alkali aluminate for a period of time sufficient to form an adherent film of alumina on said substrate; separating said substrate with said adherent film of alumina from said solution; then heating said substrate and said film of alumina under calcining conditions until said alumina film develops a desired porosity and surface area; and then contacting said calcined alumina film with a material which ameliorates the reduction in surface area and loss of structural integrity of said calcined alumina film during subsequent heating.
Claim 3
Dependent Claim
39 words
The method of claim 1 and further comprising the step of heating said substrate and said film of alumina having said material under second calcining conditions which comprise a temperature higher than that used in the first calcining conditions.
Claim 4
Dependent Claim
35 words
The method of claim 1 and further comprising the step of heating said substrate and said film of alumina having said material under second calcining conditions which comprise a temperature up to about 1260° C.
Claim 5
Dependent Claim
37 words
The method of claim 1 and further comprising the step of heating said substrate and said film of alumina having said material under second calcining conditions which comprise a temperature between about 800° C. and 1260° C.
Claim 6
Dependent Claim
19 words
The method of claim 2 wherein said substrate and said alumina film having said material are heated in air.
Claim 7
Dependent Claim
27 words
The method of claim 5 wherein said material is converted to the oxide form during the heating of said substrate and said alumina film having said material.
Claim 8
Dependent Claim
18 words
The method of claim 1 wherein said calcining conditions comprise a temperature between about 300° and 800° C.
Claim 9
Dependent Claim
30 words
The method of claim 1 wherein the step of contacting said material with said alumina film comprises contacting said alumina film with a solution comprising said material and a solvent.
Claim 10
Dependent Claim
30 words
The method of claim 1 wherein said material is selected from the group consisting of boron, alkali and alkaline earth metals, silicon, the rare earth metals, thorium, hafnium, and zirconium.
Claim 11
Dependent Claim
12 words
The method of claim 9 wherein said material comprises a barium compound.
Claim 12
Dependent Claim
12 words
The method of claim 1 wherein said alkali aluminate comprises sodium aluminate.
Claim 13
Dependent Claim
19 words
The method of claim 1 and further comprising the step of contacting said alumina film with a catalytic material.
Claim 14
Dependent Claim
113 words
A catalytic article comprising a substrate; and an adherent film of alumina formed on said substrate by contacting said substrate with an aqueous solution of an alkali hydroxide, and an alkali aluminate which solution is also in contact with aluminum metal for a period of time sufficient to form said adherent film of alumina on said substrate, then separating said substrate with said adherent film of alumina from said solution, and then heating said substrate and said adherent film of alumina under calcining conditions, and then contacting said calcined alumina film with a material which ameliorates the reduction in surface area and loss of structural integrity of said calcined alumina during subsequent heating.
Claim 15
Dependent Claim
113 words
A catalytic article comprising a substrate; and an adherent film of alumina formed on said substrate by contacting said substrate with an aqueous solution of an alkali hydroxide, and an alkali aluminate which solution is also in contact with aluminum metal for a period of time sufficient to form said adherent film of alumina on said substrate, then separating said substrate with said adherent film of alumina from said solution, and then heating said substrate and said adherent film of alumina under calcining conditions, and then contacting said calcined alumina film with a material which ameliorates the reduction in surface area and loss of structural integrity of said calcined alumina during subsequent heating.
Claim 16
Dependent Claim
51 words
The article of claim 13 wherein the steps of forming said adherent film of alumina on said substrate further comprise the step of heating said substrate and said adherent alumina film having said material under second calcining conditions which comprise a temperature higher than that used in the first calcining conditions.
Claim 17
Dependent Claim
23 words
The article of claim 13 wherein said alumina film has a thickness of from about 2×10 -3 centimeter to about 5×10 -1 centimeter.
Claim 18
Dependent Claim
21 words
The article of claim 13 wherein said alumina film further comprises a catalytic material in intimate contact with said alumina film.
Claim 19
Independent Claim
113 words
A method of substantially uniformly distributing a catalytic material on an alumina film comprising the steps of contacting a substrate and aluminum metal with an aqueous solution of an alkali hydroxide, and an alkaki aluminate for a period of time sufficient to form an adherent film of alumina on said substrate; then separating said substrate with said adherent film of alumina from said solution; then heating said substrate and said film of alumina under calcining conditions; and then contacting said calcined alumina film with a solution comprising a material which ameliorates the reduction in surface area and loss of structural integrity of said calcined alumina film during subsequent heating, and a catalytic material.
Claim 20
Independent Claim
113 words
A method of substantially uniformly distributing a catalytic material on an alumina film comprising the steps of contacting a substrate and aluminum metal with an aqueous solution of an alkali hydroxide, and an alkaki aluminate for a period of time sufficient to form an adherent film of alumina on said substrate; then separating said substrate with said adherent film of alumina from said solution; then heating said substrate and said film of alumina under calcining conditions; and then contacting said calcined alumina film with a solution comprising a material which ameliorates the reduction in surface area and loss of structural integrity of said calcined alumina film during subsequent heating, and a catalytic material.
Claim 21
Dependent Claim
42 words
The method of claim 17 and further comprising the step of heating said substrate, said alumina film having said ameliorating material, and said catalytic material under second calcining conditions which comprise a temperature higher than that used in the first calcining conditions.
Claim 22
Dependent Claim
13 words
The method of claim 17 wherein said ameliorating material comprises a barium compound.
Claim 23
Dependent Claim
42 words
The method of claim 17 wherein said catalytic material comprises one or more materials selected from the group consisting of metals and their compounds in groups IB, IIB, IVB, VB, VIB, and VIIB, and VIII of the Periodic Table of the Elements.
Claim 24
Dependent Claim
25 words
The method of claim 17 wherein said catalytic material is selected from the group consisting of the soluble forms of platinum, palladium, iridium, and rhodium.
Claim 25
Dependent Claim
10 words
A catalytic article formed by the process of claim 17.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-03-20 | 1987-09-19 | 1988-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-20 | 1991-09-19 | 1992-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-20 | 1995-09-19 | 1996-03-20 | $7700.00 | Window Closed / Lapsed |