US4122007A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reclaiming process for zeolite served for adsorbing ammoniacal nitrogen contained in sewage
Assignee: JGC Catalysts and Chemicals Ltd
•
Filing: 1976-04-15
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Granted: 1978-10-24
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Expires: 1996-04-15
Abstract
Abstract Disclosed in the present invention is a process for removing ammoniacal nitrogen from zeolite by bringing a zeolite-containing substance employed for adsorbing ammoniacal nitrogen contained in sewage into contact with an aqueous solution of sodium carbonate having a pH value of 11±1.0.
Inventors
- 👤 Tamechika Yamamoto
- 👤 Yoichi Nishimura
- 👤 Seiji Sanga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:53
CPC Classifications
B; B01; B01J; B01J39/00; B01J39/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
69 words
A process for reclaiming spent zeolite containing ammonium cations, said spent zeolite having been obtained by treating water containing ammonia with zeolite to effect cation exchange, which comprises the step of contacting said spent zeolite with an aqueous solution of sodium carbonate having a pH of 11.0±1.0 to effect removal of said ammonium cations from said spent zeolite and thereby restore the ammonium cation exchanging ability of said zeolite.
Claim 2
Dependent Claim
15 words
A process according to claim 1 in which said aqueous solution also contains sodium hydroxide.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-23 | 1982-04-24 | 1982-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-23 | 1986-04-24 | 1986-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-23 | 1990-04-24 | 1990-10-24 | $7700.00 | Window Closed / Lapsed |