US4361504A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making a silver catalyst useful in ethylene oxide production
Assignee: Dow Chemical Co
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Filing: 1981-09-04
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Granted: 1982-11-30
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Expires: 2001-09-04
Abstract
Abstract An improved process of making a silver catalyst which comprises impregnating a suitable support with an aqueous ammoniacal solution of a silver salt of an organic carboxylic acid and reducing said salt in the presence of a polyhydroxy compound.
Inventors
- 👤 Jeffry A. Solomon
- 👤 Harold W. Young, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:47
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/38; B01J23/48; B01J23/50; B01J23/54; B01J23/66; C; C07; C07D; C07D301/00; C07D301/02; C07D301/03; C07D301/04; C07D301/08; C07D301/10; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/52
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
84 words
A process for making a supported silver catalyst which comprises: a. impregnating an inert porous support material with an aqueous solution of a silver salt of an organic carboxylic acid containing ammonium hydroxide, b. drying said impregnated support material at low temperature, c. reducing said silver salt on said impregnated support material by reacting said salt with a polyhydroxy compound to form said catalyst, d. removing residual reactants from said catalyst by washing with water, and e. drying at low temperature prior to use.
Claim 2
Dependent Claim
84 words
A process for making a supported silver catalyst which comprises: a. impregnating an inert porous support material with an aqueous solution of a silver salt of an organic carboxylic acid containing ammonium hydroxide, b. drying said impregnated support material at low temperature, c. reducing said silver salt on said impregnated support material by reacting said salt with a polyhydroxy compound to form said catalyst, d. removing residual reactants from said catalyst by washing with water, and e. drying at low temperature prior to use.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein the support material is an α-alumina.
Claim 4
Dependent Claim
16 words
The process of claim 2 wherein the silver salt is the salt of a dicarboxylic acid.
Claim 5
Dependent Claim
12 words
The process of claim 3 wherein the dicarboxylic acid is oxalic acid.
Claim 6
Dependent Claim
15 words
The process of claim 1 wherein the polyhydroxy compound of step c is a glycol.
Claim 7
Dependent Claim
11 words
The process of claim 5 wherein the glycol is monoethylene glycol.
Claim 8
Dependent Claim
23 words
The process of claims 5 or 6 wherein the temperature of reduction of step c is from about 140° to about 180° C.
Claim 9
Dependent Claim
17 words
The process of claims 4, 5 or 6 wherein the aqueous ammonium hydroxide is concentrated ammonium hydroxide.
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) | 1985-11-29 | 1986-05-31 | 1986-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-11-29 | 1990-05-31 | 1990-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-11-29 | 1994-05-31 | 1994-11-30 | $7700.00 | Window Closed / Lapsed |