US4518708A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pretreatment of a fresh iridium-containing catalyst
Assignee: Mobil Oil AS
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Filing: 1984-03-07
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Granted: 1985-05-21
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Expires: 2004-03-07
Abstract
Abstract In a process for treatment of a fresh iridium-containing catalyst, the improvement consists of a three step procedure in sequence including treatment with oxygen, treatment with hydrogen chloride, and treatment with a reducing agent such as hydrogen.
Inventors
- 👤 Sowmithri Krishnamurthy
- 👤 George R. Landolt
- 👤 Hans J. Schoennagel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:07
CPC Classifications
C; C10; C10G; C10G35/00; C10G35/04; C10G35/06; C10G35/085
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
177 words
In a method of preparing a fresh metal-containing reforming catalyst wherein a porous support is impregnated with an iridium compound in combination with other metals and thereafter dried, the improvement comprising increasing the dispersion of metals on said porous support prior to exposure to a reducing atmosphere by pretreating the catalyst with oxygen, dry hydrogen halide and a reducing agent in the following sequence of steps: (1) contacting the catalyst with an oxygen-containing gas at temperatures of about 850-1000° F. with oxygen concentration of about 0.1-50 wt. % for about 0.1 to 24 hours. (2) contacting the catalyst with dry hydrogen halide at temperatures ranging from about 700-1000° F. for about 0.5 to 24 hours utilizing at least 0.1 wt. % hydrogen halide per weight of catalyst per hour; and (3) contacting the catalyst with a reducing agent at temperatures ranging from 400-1000° F. for a period of time ranging from 0.1 to 24 hours whereby said dispersion of metals is such that at least 50% of the total metal is exposed as surface metal after pretreatment.
Claim 2
Dependent Claim
177 words
In a method of preparing a fresh metal-containing reforming catalyst wherein a porous support is impregnated with an iridium compound in combination with other metals and thereafter dried, the improvement comprising increasing the dispersion of metals on said porous support prior to exposure to a reducing atmosphere by pretreating the catalyst with oxygen, dry hydrogen halide and a reducing agent in the following sequence of steps: (1) contacting the catalyst with an oxygen-containing gas at temperatures of about 850-1000° F. with oxygen concentration of about 0.1-50 wt. % for about 0.1 to 24 hours. (2) contacting the catalyst with dry hydrogen halide at temperatures ranging from about 700-1000° F. for about 0.5 to 24 hours utilizing at least 0.1 wt. % hydrogen halide per weight of catalyst per hour; and (3) contacting the catalyst with a reducing agent at temperatures ranging from 400-1000° F. for a period of time ranging from 0.1 to 24 hours whereby said dispersion of metals is such that at least 50% of the total metal is exposed as surface metal after pretreatment.
Claim 3
Dependent Claim
36 words
The process of claim 1 wherein said oxygen treatment step comprises treating said catalyst with from 0.1 to 21 wt. % of oxygen at a temperature of from 850-950° F. for about 0.25 to 2 hours.
Claim 4
Dependent Claim
15 words
The process of claim 2 wherein the oxygen is in admixture with an inert gas.
Claim 5
Dependent Claim
11 words
The process of claim 3 wherein said inert gas is nitrogen.
Claim 6
Dependent Claim
42 words
The process of claim 1 wherein said hydrogen halide treatment step comprises treating said catalyst with about 1.5% by weight of hydrogen chloride per weight of said catalyst per hour for about 2 hours at a temperature of from about 850-950° F.
Claim 7
Dependent Claim
16 words
The process of claim 5 wherein the hydrogen chloride is in admixture with an inert gas.
Claim 8
Dependent Claim
11 words
The process of claim 6 wherein said inert gas is nitrogen.
Claim 9
Dependent Claim
26 words
The process of claim 1 wherein said catalyst is treated with a reducing agent at a temperature of from about 850-950° F. for about 0.5-2 hours.
Claim 10
Dependent Claim
11 words
The process of claim 1 wherein said reducing agent is hydrogen.
Claim 11
Dependent Claim
14 words
The process of claim 1 wherein said catalyst contains the metals iridium and platinum.
Claim 12
Dependent Claim
15 words
The process of claim 1 wherein the catalyst contains the metals iridium, platinum and rhenium.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-05-20 | 1988-11-19 | 1989-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-20 | 1992-11-19 | 1993-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-20 | 1996-11-19 | 1997-05-21 | $7700.00 | Window Closed / Lapsed |