US4399633A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of alkali metal or alkaline earth metal peroxides
Assignee: Solvay Interox Ltd
•
Filing: 1981-04-09
•
Granted: 1983-08-23
•
Expires: 2001-04-09
Abstract
Abstract Alkali metal or alkaline earth metal peroxides, for example, particularly, calcium peroxide, are produced by recovering a moist peroxide product from an aqueous mixture, formed by reacting hydrogen peroxide and a hydroxide or oxide of the alkali metal or alkaline earth metal, and drying the moist product by means of a pneumatic conveyer drier. The peroxide so produced is suitable for granulation. Alternatively, particulate substances, such as seed, are coated with the peroxide by blending with the moist peroxide product and passing the blend through the pneumatic conveyer drier.
Inventors
- 👤 Douglas P. Haughey
- 👤 Malcolm H. Millar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 04:59
CPC Classifications
C; C01; C01B; C01B15/00; C01B15/04; C01B15/043; C01B15/0435
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
95 words
A process for the preparation of an alkali metal or an alkaline earth metal peroxide comprising reacting hydrogen peroxide and a hydroxide or oxide of the alkali metal or alkaline earth metal in an aqueous medium, separating the peroxide from the aqueous medium in the form of a moist peroxide product, and drying the moist peroxide product by means of a direct fired pneumatic conveyor drier, said moist peroxide having a moisture content of from 10% to 45% by weight, and said drier being operated at an air inlet temperature of at least 150° C.
Claim 2
Dependent Claim
95 words
A process for the preparation of an alkali metal or an alkaline earth metal peroxide comprising reacting hydrogen peroxide and a hydroxide or oxide of the alkali metal or alkaline earth metal in an aqueous medium, separating the peroxide from the aqueous medium in the form of a moist peroxide product, and drying the moist peroxide product by means of a direct fired pneumatic conveyor drier, said moist peroxide having a moisture content of from 10% to 45% by weight, and said drier being operated at an air inlet temperature of at least 150° C.
Claim 3
Dependent Claim
29 words
A process as claimed in claim 1 wherein the moisture content of the moist peroxide product is at least in part controlled by the addition of already dry material.
Claim 4
Dependent Claim
29 words
A process as claimed in claim 2 wherein the already dry material consists of or includes material other than recycled previously dried alkali metal or alkaline earth metal peroxide.
Claim 5
Dependent Claim
33 words
A process as claimed in claim 3 wherein the already dry material comprises one or more fillers for the alkali metal or alkaline earth metal peroxide or one or more fertilisers or seed.
Claim 6
Dependent Claim
22 words
A process as claimed in claim 1 wherein moist peroxide product has a moisture content of not more than 35% by weight.
Claim 7
Dependent Claim
23 words
A process as claimed in claim 5 wherein the moist peroxide product has a moisture content of from 15% to 35% by weight.
Claim 8
Dependent Claim
35 words
A process as claimed in claim 1 wherein the pneumatic conveyer drier is operated at an inlet air temperature of up to 550° C. and to give a residence time of at least 1 second.
Claim 9
Dependent Claim
30 words
A process as claimed in claim 7 wherein the pneumatic conveyor drier includes one or more delay chambers so as to give a residence time of at least 2 seconds.
Claim 10
Dependent Claim
23 words
A process as claimed in claim 1 wherein the moist peroxide product is produced by centrifugation or filtration of the peroxide-containing aqueous medium.
Claim 11
Dependent Claim
27 words
A process as claimed in claim 1 wherein the dried alkali metal or alkaline earth metal peroxide has a moisture content of less than 0.5% by weight.
Claim 12
Dependent Claim
19 words
A process as claimed in claim 1 wherein the alkali metal or alkaline earth metal peroxide is calcium peroxide.
Claim 13
Dependent Claim
49 words
A process as claimed in claim 1 wherein the pneumatic conveyer drier is operated at an inlet temperature of at least 150° C., wherein the residence time in said drier is from 1 to 20 seconds, and wherein the dried product has a moisture content of less than 0.5%.
References Cited (Backward Citations)
US1308942A
Cited
US2290862A
Cited
US2350162A
Cited
US2357655A
Cited
US2533660A
Cited
US2783544A
Cited
GB799251A
Cited
US3151951A
Cited
US3475132A
Cited
US3386182A
Cited
US3464121A
Cited
US3786573A
Cited
US3789513A
Cited
US3879856A
Cited
JPS5269711A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-22 | 1987-02-21 | 1987-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-22 | 1991-02-21 | 1991-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-22 | 1995-02-21 | 1995-08-23 | $7700.00 | Window Closed / Lapsed |