US3728442A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing vanadium pentoxide
Assignee: Individual
•
Filing: 1971-06-07
•
Granted: 1973-04-17
•
Expires: 1991-06-07
Abstract
Abstract A method of producing vanadium pentoxide, characterized in that ammonium vanadate is treated with a 2.0 - 2.5 N. mineral acid at a H /VO3 ratio 1.0 - 1.1 g-equiv. The resultant vanadium acid precipitate is separated from the mother liquor, washed with water to the pH value of the washings equal to 4 - 5 and calcined at a temperature of 500* - 600* C. The proposed method makes possible the production of a granulated dustless final product of a high degree of purity.
Inventors
- 👤 D Pakhomov
- 👤 S Arkhipov
- 👤 A Pruntsev
- 👤 S Milsky
- 👤 A Pleskachev
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:36
CPC Classifications
C; C01; C01G; C01G31/00; C01G31/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
30 words
A method as claimed in claim 1 wherein the precipitate is washed with a 0.2 - 0.5 per cent solution of hydrochloric or nitric acid prior to washing with water.
Claim 2
Dependent Claim
23 words
A method as claimed in claim 1 wherein the precipitate is dried at a temperature of up to 300* C. prior to calcination.
Claim 3
Dependent Claim
41 words
A method as claimed in claim 1 wherein the reaction mixture of ammonium vanadate and 2.0 - 2.5 N solution of hydrochloric or nitric acid is formed by adding concentrated hydrochloric or nitric acid to an aqueous suspension of ammonium vanadate.
Claim 4
Dependent Claim
26 words
A method as claimed in claim 1 wherein the initial reaction mixture is prepared using recycled wash water from the washing of the vanadic acid precipitate.
Claim 5
Dependent Claim
62 words
A method as claimed in claim 2 wherein the ammonium vanadate is prepared by treating an aqueous solution of an alkali metal vanadate with the recycled mother liquor from the precipitation of vanadic acid and the recycled wash solution of 0.2 - 0.5 per cent hydrochloric or nitric acid, said mother liquor and wash solution having been previously neutralized with ammonium carbonate.
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) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |