US4100098A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stabilized solutions of sodium dithionite
Assignee: Olin Corp
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Filing: 1976-10-26
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Granted: 1978-07-11
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Expires: 1996-10-26
Abstract
Abstract Aqueous solutions containing mixtures of sodium dithionite and sodium sulfite having concentrations of greater than 13 percent by weight of Na2S2O4 are stabilized by adding potassium hydroxide in an amount which is sufficient to provide a residual of from about 1 to about 12 grams per liter of solution. These solutions can be stored at temperatures of from about 0 DEG to about 15 DEG C. without crystallization taking place.
Inventors
- 👤 Phillip R. Magan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:43
CPC Classifications
D; D06; D06P; D06P1/00; D06P1/22; D06P1/221; C; C01; C01B; C01B17/00; C01B17/64; C01B17/66; C01B17/665; D06L; D06L4/00; D06L4/30
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
95 words
A method of stabilizing aqueous solutions of mixtures of sodium dithionite and sodium sulfite which comprises: (a) preparing an aqueous solution containing greater than about 13 percent by weight of of sodium dithionite and at least one percent of sodium sulfite by weight of said sodium dithionite, (b) adding potassium hydroxide to said aqueous solution of an amount sufficient to provide a residual of potassium hydroxide in the solutions of from about 1 to about 12 grams per liter, (c) maintaining the aqueous solution at a temperature of from about 0° to about 15° C.
Claim 2
Independent Claim
95 words
A method of stabilizing aqueous solutions of mixtures of sodium dithionite and sodium sulfite which comprises: (a) preparing an aqueous solution containing greater than about 13 percent by weight of of sodium dithionite and at least one percent of sodium sulfite by weight of said sodium dithionite, (b) adding potassium hydroxide to said aqueous solution of an amount sufficient to provide a residual of potassium hydroxide in the solutions of from about 1 to about 12 grams per liter, (c) maintaining the aqueous solution at a temperature of from about 0° to about 15° C.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein said potassium hydroxide is added as an aqueous solution containing at least about 30 percent by weight of KOH.
Claim 4
Dependent Claim
25 words
The method of claim 2 wherein said residual of potassium hydroxide in the solution is from about 3 to about 8 L grams per liter.
Claim 5
Dependent Claim
22 words
The method of claim 1 wherein said aqueous solution is maintained at a temperature of from about 0° to about 7° C.
Claim 6
Dependent Claim
27 words
The method of claim 4 wherein said potassium hydroxide is added as an aqueous solution containing from about 40 to about 60 percent by weight of KOH.
Claim 7
Dependent Claim
21 words
The method of claim 5 wherein said residual of potassium hydroxide is from about 3 to about 8 grams per liter.
Claim 8
Dependent Claim
22 words
The method of claim 6 wherein said aqueous solution contains from about 13 to about 15 percent by weight of sodium dithionite.
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) | 1981-07-10 | 1982-01-09 | 1982-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-10 | 1986-01-09 | 1986-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-10 | 1990-01-09 | 1990-07-11 | $7700.00 | Window Closed / Lapsed |