Patent US4410722A successfully refreshed from Google Patents.
US4410722A
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Process for preparing oxalic acid diesters using platinum group metals supported on alumina
Assignee: Ube Corp
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Filing: 1982-01-11
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Granted: 1983-10-18
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Expires: 2002-01-11
Abstract
Abstract In a process for preparing a diester of oxalic acid by the vapor phase catalytic reaction of carbon monoxide with an ester of nitrous acid in the presence of a catalyst composed of a solid carrier and a platinum-group metal or a salt thereof supported on the carrier, the improvement wherein said solid carrier is alumina having a specific surface area of not more than 90 m2/g.
Inventors
- 👤 Haruhiko Miyazaki
- 👤 Yasushi Shiomi
- 👤 Satoru Fujitus
- 👤 Katsuro Masunaga
- 👤 Hiroshi Yanagisawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:04
CPC Classifications
C; C07; C07C; C07C69/00; C07C69/34; C07C69/36; B; B01; B01J; B01J23/00; B01J23/38; B01J23/40; B01J23/44; B01J37/00; B01J37/02; B01J37/03; B01J37/031; B01J37/035; B01J37/16; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/582
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
69 words
In a process for preparing a diester of oxalic acid by the vapor phase catalytic reaction of carbon monoxide with an ester of nitrous acid in the presence of a catalyst composed of a solid carrier and a platinum-group metal or a salt thereof supported on the carrier, the improvement wherein said solid carrier is alumina having a specific surface area of not more than 90 m 2 /g.
Claim 2
Dependent Claim
69 words
In a process for preparing a diester of oxalic acid by the vapor phase catalytic reaction of carbon monoxide with an ester of nitrous acid in the presence of a catalyst composed of a solid carrier and a platinum-group metal or a salt thereof supported on the carrier, the improvement wherein said solid carrier is alumina having a specific surface area of not more than 90 m 2 /g.
Claim 3
Dependent Claim
39 words
The process of claim 1 wherein the ester of nitrous acid is an ester of nitrous acid with an alcohol having 1 to 8 carbon atoms selected from the group consisting of saturated monohydric aliphatic alcohols and alicyclic alcohols.
Claim 4
Dependent Claim
20 words
The process of claim 1 wherein the alumina has a specific surface area of 0.05 to 70 m 2 /g.
Claim 5
Dependent Claim
22 words
The process of claim 1 wherein the reaction is carried out at a temperature of about 50° C. to about 200° C.
Claim 6
Dependent Claim
20 words
The process of claim 1 wherein the reaction is carried out at atmospheric pressure to about 10 kg/cm 2 .G.
Claim 7
Dependent Claim
29 words
The process of claim 1 wherein the amount of the platinum-group metal supported is 0.01 to 10% by weight, as metal, based on the weight of the alumina carrier.
Claim 8
Dependent Claim
61 words
The process of claim 1 wherein the catalyst is prepared by impregnating the alumina having a specific surface area of not more than 90 m 2 /g with an aqueous solution of a water soluble salt of the platinum-group metal, treating the impregnated alumina with an alkali, and then subjecting the alkali-treated product to reduction in the liquid or gaseous phase.
Claim 9
Dependent Claim
23 words
The process of claim 7 wherein the alkali is a hydroxide, carbonate or bicarbonate of an alkali metal or an alkaline earth metal.
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) | 1986-10-17 | 1987-04-18 | 1987-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-17 | 1991-04-18 | 1991-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-17 | 1995-04-18 | 1995-10-18 | $7700.00 | Window Closed / Lapsed |