US4284515A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for decreasing elemental phosphorus levels in an aqueous medium
Assignee: Syensqo USA LLC
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Filing: 1979-12-10
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Granted: 1981-08-18
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Expires: 1999-12-10
Abstract
Abstract A process is provided for decreasing elemental phosphorus levels in an aqueous medium containing elemental phosphorus. Preferably, the elemental phosphorus levels are at about 10 ppm or less. The process comprises adding to the aqueous medium an effective amount of caustic, preferably Ca(OH)2, the effective amount being an amount sufficient to increase the pH of the aqueous medium to at least about 11, to produce a basic aqueous medium. The basic aqueous medium is then clarified and neutralized.
Inventors
- 👤 Chong T. Liu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:20
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/66; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/906
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
102 words
A process for decreasing elemental phosphorus levels in an aqueous medium containing elemental phosphorus comprising adding to the aqueous medium an effective amount of caustic of the formula M(OH) n wherein M is selected from the group consisting of lithium, sodium, potassium, magnesium, calcium and barium, and n is a valence factor for M, being 1 where M is selected from lithium, sodium and potassium and 2 where M is selected from magnesium, calcium and barium, the effective amount being an amount sufficient to increase the pH of the aqueous medium to at least about 11, to produce a basic aqueous medium.
Claim 2
Dependent Claim
102 words
A process for decreasing elemental phosphorus levels in an aqueous medium containing elemental phosphorus comprising adding to the aqueous medium an effective amount of caustic of the formula M(OH) n wherein M is selected from the group consisting of lithium, sodium, potassium, magnesium, calcium and barium, and n is a valence factor for M, being 1 where M is selected from lithium, sodium and potassium and 2 where M is selected from magnesium, calcium and barium, the effective amount being an amount sufficient to increase the pH of the aqueous medium to at least about 11, to produce a basic aqueous medium.
Claim 3
Dependent Claim
12 words
The process of claim 1, wherein the caustic is Ca(OH) 2 .
Claim 4
Dependent Claim
16 words
The process of claim 1, wherein the elemental phosphorus levels are about 10 ppm or less.
Claim 5
Dependent Claim
16 words
The process of claim 1, wherein the elemental phosphorus levels are about 3 ppm or less.
Claim 6
Dependent Claim
18 words
The process of claim 1, further comprising clarifying the basic aqueous medium to produce a clarified aqueous medium.
Claim 7
Dependent Claim
13 words
The process of claim 5, further comprising substantially neutralizing the clarified aqueous medium.
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) | 1984-08-17 | 1985-02-16 | 1985-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-17 | 1989-02-16 | 1989-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-17 | 1993-02-16 | 1993-08-18 | $7700.00 | Window Closed / Lapsed |