US3948769A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ligand exchange process for removal of ammonia
Assignee: Environmental Protection Agency
•
Filing: 1974-04-08
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Granted: 1976-04-06
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Expires: 1994-04-08
Abstract
Abstract The selective removal of ammonia from waste water is achieved by the use of a ligand exchanger which has been conditioned with a salt of a metal which is capable of forming a complex with ammonia. The ligand exchanger is regenerated by contacting it with low pressure steam.
Inventors
- 👤 Richard A. Dobbs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:42
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/28; C02F1/281; B; B01; B01J; B01J45/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
87 words
A process for removing ammonia from waste water which comprises: conditioning a hydrous zirconium oxide ligand exchanger to accept ammonia in solution, by contacting said exchanger with a strongly basic solution of a metal capable of forming a complex with NH 3 ; thereafter bringing an ammonia containing solution into contact with said conditioned ligand exchanger whereby ammonia is complexed with said exchanger; and regenerating said ligand exchanger by contacting it with steam at a pressure of about 30 PSIG and at a temperature of about 135°C.
Claim 2
Dependent Claim
87 words
A process for removing ammonia from waste water which comprises: conditioning a hydrous zirconium oxide ligand exchanger to accept ammonia in solution, by contacting said exchanger with a strongly basic solution of a metal capable of forming a complex with NH 3 ; thereafter bringing an ammonia containing solution into contact with said conditioned ligand exchanger whereby ammonia is complexed with said exchanger; and regenerating said ligand exchanger by contacting it with steam at a pressure of about 30 PSIG and at a temperature of about 135°C.
References Cited (Backward Citations)
US3332737A
Cited
US3842000A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-06 | 1979-10-06 | 1980-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-06 | 1983-10-06 | 1984-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-06 | 1987-10-06 | 1988-04-06 | $7700.00 | Window Closed / Lapsed |