Patent US3909408A successfully refreshed from Google Patents.
US3909408A
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Process for treating aldehydes
Assignee: Asahi Kasei Corp
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Filing: 1974-01-02
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Granted: 1975-09-30
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Expires: 1994-01-02
Abstract
Abstract A process is provided for the effective removal of aldehyde from a mixture containing aldehyde which is either a gas or a solution which comprises treating said mixture at a pH of 6-11 with a mixed sulfite-bisulfite treating agent, whereby the aldehyde of said mixture is ecologically-efficiently eliminated.
Inventors
- 👤 Shinichi Ishida
- 👤 Noboru Oshima
- 👤 Kunio Kurita
- 👤 Isamu Suzuki
- 👤 Hidetoshi Ohno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:57
CPC Classifications
C; C07; C07C; C07C45/00; C07C45/78; C07C45/783; B; B01; B01D; B01D53/00; B01D53/34; C07C45/80; C02; C02F; C02F2101/00; C02F2101/30; C02F2101/34
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
59 words
A PROCESS FOR THE EFFECTIVE REMOVAL OF FORMALDEHYDE FROM A MIXTURE CONTAINING FORMALDEHYDE, WHICH MIXTURE IS EITHER A GAS OR A SOLUTION, WHICH COMPRISES TREATING SAID MIXTURE AT A PH OF 6-11 WITH AN AQUEOUS SOLUTION OF A MIXED SODIUM SULFITE-SODIUM BISULFITE TREATING AGENT, THE AMOUNT OF SAID BISULFITE BEING 0.1 TO 10 MOLS PER MOL OF SAID SULFITE.
Claim 2
Dependent Claim
59 words
A PROCESS FOR THE EFFECTIVE REMOVAL OF FORMALDEHYDE FROM A MIXTURE CONTAINING FORMALDEHYDE, WHICH MIXTURE IS EITHER A GAS OR A SOLUTION, WHICH COMPRISES TREATING SAID MIXTURE AT A PH OF 6-11 WITH AN AQUEOUS SOLUTION OF A MIXED SODIUM SULFITE-SODIUM BISULFITE TREATING AGENT, THE AMOUNT OF SAID BISULFITE BEING 0.1 TO 10 MOLS PER MOL OF SAID SULFITE.
Claim 3
Dependent Claim
17 words
A process of claim 1, wherein the ratio of sodium sulfite to sodium bisulfite is about 5:1.
References Cited (Backward Citations)
US3660278A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |