US3761575A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the cracking of ammonium sulfate
Assignee: Davy McKee AG
•
Filing: 1972-03-03
•
Granted: 1973-09-25
•
Expires: 1992-03-03
Abstract
Abstract For converting ammonium sulfate into ammonia and sulfur dioxide, the steps of: (a) heating ammonium sulfate to 300*-500* C. to produce ammonia and ammonium bisulfate; and (b) burning resultant ammonium bisulfate at 850*-1,250* C. with a carbon-containing fuel and sufficient oxygen to maintain the gases exiting from the combustion chamber, at an oxygen concentration of between 1 and 8% by volume.
Inventors
- 👤 H Furkert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:33
CPC Classifications
C; C01; C01B; C01B17/00; C01B17/48; C01B17/50; C01B17/501; C01B17/504; C01C; C01C1/00; C01C1/02; C01C1/026; C01C1/028; Y; Y02; Y02P; Y02P20/00; Y02P20/10; Y02P20/129
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
27 words
The process according to claim 1, wherein said ammonium bisulfate is burned by introducing said ammonium bisulfate in the liquid state through nozzles into a combustion zone.
Claim 2
Dependent Claim
15 words
The process according to claim 1, wherein said ammonium bisulfate is burned at 950*-1150* C.
Claim 3
Dependent Claim
26 words
The process according to claim 1, wherein said gases exiting from the combustion chamber have an oxygen concentration of between 1.8 and 4.5 percent by volume.
Claim 4
Dependent Claim
17 words
The process according to claim 1 further comprising adding sulfur during the step of burning ammonium bisulfate.
Claim 5
Dependent Claim
27 words
The process according to claim 1, wherein said ammonium bisulfate is burned containing up to 11.5 parts by weight ammonium sulfate based on 100 parts ammonium bisulfate.
Claim 6
Dependent Claim
33 words
The process according to claim 1, wherein said process is continuous and in step (a) a steady state molar ratio of ammonium sulfate to ammonium bisulfate of 0.01:1 to 0.1:1, respectively, is maintained.
Claim 7
Dependent Claim
14 words
The process according to claim 7, wherein the molar ratio is 0.02:1 to 0.085:1.
Claim 8
Dependent Claim
23 words
The process according to claim 7, wherein ammonium sulfate is continously added to an agitated melt containing said ammonium sulfate and ammonium bisulfate.
Claim 9
Dependent Claim
22 words
The process according to claim 7, wherein 10-50 percent of the ammonium bisulfate produced in step (a) is recycled to step (a).
Claim 10
Dependent Claim
24 words
The process according to claim 1, wherein the ammonium bisulfate melt obtained from step (a) is treated with superheated steam to remove ammonia therefrom.
Claim 11
Dependent Claim
24 words
The process according to claim 10, wherein the ammonium bisulfate melt obtained from step (a) is treated with superheated steam to remove ammonia therefrom.
Claim 12
Dependent Claim
25 words
A process as defined by claim 1, wherein a stream of nitrogen or superheated steam is employed in step (a) to entrain the ammonia formed.
Claim 13
Dependent Claim
93 words
A process for cracking by-product ammonium sulfate from the production of epsilon -caprolactam by Beckmann rearrangement of cyclohexanone oxime, into ammonia and sulfur dioxide, comprising the steps of: a. heating the by-product ammonium sulfate to 300*-500*C to produce ammonia and ammonium bisulfate; b. neutralizing the mixture obtained during said Beckmann rearrangement with ammonia formed in (a) and c. burning resultant ammonium bisulfate melt at 850*-1,250*C with a carbon-containing fuel and sufficient oxygen to maintain the gases exiting from the combustion chamber, at an oxygen concentration of between 1 and 8 percent by volume.
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) | 1976-09-24 | 1977-03-26 | 1977-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-24 | 1981-03-26 | 1981-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-24 | 1985-03-26 | 1985-09-25 | $7700.00 | Window Closed / Lapsed |