US4073706A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brine treatment for trace metal removal
Assignee: Diamond Shamrock Corp
•
Filing: 1976-02-06
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Granted: 1978-02-14
•
Expires: 1996-02-06
Abstract
Abstract Process for the removal of trace metals from alkali halide brines. The addition of controlled amounts of magnesium ions to brine and subsequent precipitation of magnesium hydroxide removes metal contaminants, and provides a brine suitable for use in the electrolytic production of chlorine and alkali metal hydroxide.
Inventors
- 👤 Zoltan Nagy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 00:23
CPC Classifications
C; C01; C01D; C01D3/00; C01D3/14; C01D3/16; C25; C25B; C25B15/00; C25B15/08
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
80 words
A method for reducing the trace metals content of an aqueous alkali metal chloride solution containing less than abaout 5 ppm of magnesium followed by electrolysis of the solution, which comprises a. adding soluble magnesium compound to the solution to establish a magnesium concentration of greater than 5 ppm, b. precipitating the magnesium as Mg(OH) 2 , c. separating the precipitate containing said trace metals from the solution, and d. electrolyzing the solution to produce chlorine and alkali metal hydroxide.
Claim 2
Independent Claim
80 words
A method for reducing the trace metals content of an aqueous alkali metal chloride solution containing less than abaout 5 ppm of magnesium followed by electrolysis of the solution, which comprises a. adding soluble magnesium compound to the solution to establish a magnesium concentration of greater than 5 ppm, b. precipitating the magnesium as Mg(OH) 2 , c. separating the precipitate containing said trace metals from the solution, and d. electrolyzing the solution to produce chlorine and alkali metal hydroxide.
Claim 3
Dependent Claim
25 words
Method as recited in claim 1 wherein the magnesium is precipitated by adjusting the solution pH to the range of abaout 8 to about 12.
Claim 4
Dependent Claim
16 words
Method as recited in claim 2 wherein the pH is adjusted by the addition of NaOH.
Claim 5
Dependent Claim
27 words
Method as recited in claim 1 wherein the trace metals present in the solution include at least one of aluminum, antimony, arsenic, molybdenum, strontium, tantalum, or vanadium.
Claim 6
Dependent Claim
14 words
Method as recited in claim 1 wherein the alkali metal chloride is sodium chloride.
Claim 7
Dependent Claim
15 words
Method as recited in claim 1 wherein the soluble magnesium compound is MgCl 2 .
Claim 8
Dependent Claim
19 words
Method as recited in claim 1 wherein the Mg +2 concentration is established in the range of 5-200 ppm.
Claim 9
Dependent Claim
16 words
Method as recited in claim 1 wherein the precipitate is separated from the solution by filtration.
References Cited (Backward Citations)
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Cited
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Cited
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Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-13 | 1981-08-15 | 1982-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-13 | 1985-08-15 | 1986-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-13 | 1989-08-15 | 1990-02-14 | $7700.00 | Window Closed / Lapsed |