US4210460A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spill control composition and use thereof
Assignee: Avantor Performance Materials LLC
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Filing: 1975-10-22
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Granted: 1980-07-01
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Expires: 1995-10-22
Abstract
Abstract A spill of hydrofluoric acid is controlled and cleaned up by being treated with a composition comprising an aqueous solution of calcium acetate and applying to the resulting precipitate an activated composition of powdered magnesia and an appropriate normally solid pH indicator.
Inventors
- 👤 James W. Seidenberger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:05
CPC Classifications
A; A62; A62D; A62D3/00; A62D3/30; A62D3/36; B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/68; C; C09; C09K; C09K3/00; C09K3/32; A62D2101/00; A62D2101/40; A62D2101/49; Y; Y02; Y02C; Y02C20/00; Y02C20/30
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
137 words
A method for the control and cleanup of spilled hydrofluoric acid comprising first applying to the spilled hydrofluoric acid an aqueous solution of about 25 to 29% by weight of calcium acetate and about 71 to 75% by weight of water and thereafter applying to said spilled hydrofluoric acid a powdered composition of about 99.90 to 99.99% by weight powdered magnesium oxide and about 0.01 to 0.10% by weight of a solid pH indicator changing color in the range pH 6.0-8.0, which powdered composition has first been activated by the addition of at least 350 ml of water per 110 grams of powdered composition, and thereafter disposing of the resulting treated hydrofluoric acid slurry after a change in color of the pH indicator in the slurry evidences that the slurry has reached an essentially safe pH condition.
Claim 2
Independent Claim
137 words
A method for the control and cleanup of spilled hydrofluoric acid comprising first applying to the spilled hydrofluoric acid an aqueous solution of about 25 to 29% by weight of calcium acetate and about 71 to 75% by weight of water and thereafter applying to said spilled hydrofluoric acid a powdered composition of about 99.90 to 99.99% by weight powdered magnesium oxide and about 0.01 to 0.10% by weight of a solid pH indicator changing color in the range pH 6.0-8.0, which powdered composition has first been activated by the addition of at least 350 ml of water per 110 grams of powdered composition, and thereafter disposing of the resulting treated hydrofluoric acid slurry after a change in color of the pH indicator in the slurry evidences that the slurry has reached an essentially safe pH condition.
Claim 3
Independent Claim
129 words
A method for the control and cleanup of spilled hydrofluoric acid comprising first applying to the spilled hydrofluoric acid an aqueous solution of about 163 parts by weight of calcium acetate and about 440 parts by weight of deionized water and thereafter applying to said spilled hydrofluoric acid a powdered composition of about 100 parts by weight powdered magnesium oxide and about 0.04 parts by weight of bromothymol blue sodium salt, which powdered composition has first been activated by the addition of at least 350 ml of water per 110 grams of powdered composition, and thereafter disposing of the resulting treated hydrofluoric acid slurry after a change in color of the bromothymol blue sodium salt in the slurry evidences that the slurry has reached an essentially safe pH condition.
Claim 4
Independent Claim
129 words
A method for the control and cleanup of spilled hydrofluoric acid comprising first applying to the spilled hydrofluoric acid an aqueous solution of about 163 parts by weight of calcium acetate and about 440 parts by weight of deionized water and thereafter applying to said spilled hydrofluoric acid a powdered composition of about 100 parts by weight powdered magnesium oxide and about 0.04 parts by weight of bromothymol blue sodium salt, which powdered composition has first been activated by the addition of at least 350 ml of water per 110 grams of powdered composition, and thereafter disposing of the resulting treated hydrofluoric acid slurry after a change in color of the bromothymol blue sodium salt in the slurry evidences that the slurry has reached an essentially safe pH condition.
References Cited (Backward Citations)
US475586A
Cited
US2601862A
Cited
US2073398A
Cited
US2270025A
Cited
US2997445A
Cited
US3638785A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-07-01 | 1983-12-31 | 1984-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-01 | 1987-12-31 | 1988-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-01 | 1991-12-31 | 1992-07-01 | $7700.00 | Window Closed / Lapsed |