US3895099A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for manufacture of calcium hydrochlorite
Assignee: Olin Corp
•
Filing: 1973-03-12
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Granted: 1975-07-15
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Expires: 1993-03-12
Abstract
Abstract A continuous process for the manufacture of calcium hypochlorite in which an aqueous slurry of lime and sodium hypochlorite is chlorinated in a mixing zone to form a sodium chloride solution containing large crystals of calcium hypochlorite which are readily separated and dried. The resulting solution containing some dissolved calcium hypochlorite is reacted with an alkali metal hydroxide to precipitate lime, which is separated and recycled to the mixing zone slurry. The lime-free solution may be used as bleach liquor or processed to precipitate solid salt useful in the preparation of brine. The remaining solution is recycled to the mixing zone slurry. Purification of fresh lime is also disclosed. The process provides an improved separation of calcium hypochlorite and sodium chloride, and recycles all solutions to minimize pollution of water resources.
Inventors
- 👤 Walter J Sakowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:35
CPC Classifications
C; C01; C01B; C01B11/00; C01B11/04; C01B11/06; C01B11/064; C01B15/00; C01B15/01; C01B15/03; C01F; C01F11/00; C01F11/02; D; D06; D06L; D06L4/00; D06L4/20; D06L4/22; D06L4/23
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
40 words
A CONTINUOUS PROCESS FOR PREPARING CALCIUM HYPOCHLORITE WHICH COMPRISES: A. REACTTING AN AQUEOUS SLURRY OF IMPURE LIME WITH CHLORINE TO FORM A SLURRY OF INSOLUBLE IMPURITIES OF SAID LIME SUSPENDED IN AN AQUEOUS SLOUTION OF SOLUBLE REACTION PRODUCTS COMPRISED OF
Claim 2
Dependent Claim
40 words
A CONTINUOUS PROCESS FOR PREPARING CALCIUM HYPOCHLORITE WHICH COMPRISES: A. REACTTING AN AQUEOUS SLURRY OF IMPURE LIME WITH CHLORINE TO FORM A SLURRY OF INSOLUBLE IMPURITIES OF SAID LIME SUSPENDED IN AN AQUEOUS SLOUTION OF SOLUBLE REACTION PRODUCTS COMPRISED OF
Claim 3
Dependent Claim
3 words
CALCIUM HYPOCHLORITE, AND
Claim 4
Dependent Claim
3 words
CALCIUM HYPOCHLORITE, AND
Claim 5
Dependent Claim
7 words
SOLID CALCIUM HYPOCHLORITE DITHYDRATE PARTICLES ADMIXED WITH
Claim 6
Dependent Claim
7 words
SOLID CALCIUM HYPOCHLORITE DITHYDRATE PARTICLES ADMIXED WITH
Claim 7
Dependent Claim
4 words
SAID PASTE LIQUOR AND
Claim 8
Dependent Claim
4 words
SAID PASTE LIQUOR AND
Claim 9
Dependent Claim
32 words
A PASTE LIQUOR COMPRISED OF AN AQUEOUS SOLUTION OF A. ALKALI METAL CHLORIDE, AND B. DISSOLVED CALCIUM HYPOCHLORITE, E. CONTINUOUSLY WITHDRAWING AT LEAST A PORTION OF SAID PASTE AND SEPARATING IT INTO
Claim 10
Dependent Claim
32 words
A PASTE LIQUOR COMPRISED OF AN AQUEOUS SOLUTION OF A. ALKALI METAL CHLORIDE, AND B. DISSOLVED CALCIUM HYPOCHLORITE, E. CONTINUOUSLY WITHDRAWING AT LEAST A PORTION OF SAID PASTE AND SEPARATING IT INTO
Claim 11
Dependent Claim
53 words
CALCIUM CHLORIDE, B. SEPARATING SAID INSOLUBLE IMPURITIES FROM SAID AQUEOUS SOLUTION OF SAID REACTION PRODUCTS, C. REACTING SAID AQUEOUS SOLUTION OF SAID REACTION PRODUCTS WITH AN ALKALI METAL HYPOCHLORITE IN A MIXING ZONE TO FROM A MIXING ZONE SLURRY, D. REACTING SAID MIXING ZONE SLURRY WITH CHLORINE TO FROM A PASTE COMPRISED OF:
Claim 12
Dependent Claim
53 words
CALCIUM CHLORIDE, B. SEPARATING SAID INSOLUBLE IMPURITIES FROM SAID AQUEOUS SOLUTION OF SAID REACTION PRODUCTS, C. REACTING SAID AQUEOUS SOLUTION OF SAID REACTION PRODUCTS WITH AN ALKALI METAL HYPOCHLORITE IN A MIXING ZONE TO FROM A MIXING ZONE SLURRY, D. REACTING SAID MIXING ZONE SLURRY WITH CHLORINE TO FROM A PASTE COMPRISED OF:
Claim 13
Dependent Claim
19 words
The process of claim 1 wherein lime and a hydroxide of alkali metal are fed to said mixing zone.
Claim 14
Dependent Claim
66 words
a moist cake of said solid calcium hypochlorite dihydrate particles, f. reacting said paste liquor with a hydroxide of an alkali metal to form a slurry of precipitated lime in a mother liquor predominating in alkali metal hypochlorite and alkali metal chloride, g. separating said precipitated lime from at least a portion of said mother liquor, and h. recycling said precipitated lime to said mixing zone.
Claim 15
Dependent Claim
66 words
a moist cake of said solid calcium hypochlorite dihydrate particles, f. reacting said paste liquor with a hydroxide of an alkali metal to form a slurry of precipitated lime in a mother liquor predominating in alkali metal hypochlorite and alkali metal chloride, g. separating said precipitated lime from at least a portion of said mother liquor, and h. recycling said precipitated lime to said mixing zone.
Claim 16
Dependent Claim
32 words
a paste liquor comprised of an aqueous solution of a. alkali metal chloride, and b. dissolved calcium hypochlorite, e. continuously withdrawing at least a portion of said paste and separating it into
Claim 17
Dependent Claim
32 words
a paste liquor comprised of an aqueous solution of a. alkali metal chloride, and b. dissolved calcium hypochlorite, e. continuously withdrawing at least a portion of said paste and separating it into
Claim 18
Dependent Claim
53 words
calcium chloride, b. separating said insoluble impurities from said aqueous solution of said reaction products, c. reacting said aqueous solution of said reaction products with an alkali metal hypochlorite in a mixing zone to form a mixing zone slurry, d. reacting said mixing zone slurry with chlorine to form a paste comprised of:
Claim 19
Dependent Claim
53 words
calcium chloride, b. separating said insoluble impurities from said aqueous solution of said reaction products, c. reacting said aqueous solution of said reaction products with an alkali metal hypochlorite in a mixing zone to form a mixing zone slurry, d. reacting said mixing zone slurry with chlorine to form a paste comprised of:
Claim 20
Dependent Claim
66 words
A MOIST CAKE OF SAID SOLID CALCIUM HYPOCHLORITE DIHYDRATE PARTICLES, F. REACTING SAID PASTE LIQUOR WITH A HYDROXIDE OF AN ALKALI METAL TO FORM A SLURRY OF PRECIPITATED LIME IN A MOTHER LIQOUR PREDOMINATING IN ALKALI METAL HYPOCHLORITE AND ALKALI METAL CHLORIDE, G. SEPARATING SAID PRECIPTATED LIME FROM AT LEAST A PORTION OF SAID MOTHER LIQUOR, AND H. RECYCLING SAID PRECIPITATED LIME TO SAID MIXING ZONE.
Claim 21
Dependent Claim
66 words
A MOIST CAKE OF SAID SOLID CALCIUM HYPOCHLORITE DIHYDRATE PARTICLES, F. REACTING SAID PASTE LIQUOR WITH A HYDROXIDE OF AN ALKALI METAL TO FORM A SLURRY OF PRECIPITATED LIME IN A MOTHER LIQOUR PREDOMINATING IN ALKALI METAL HYPOCHLORITE AND ALKALI METAL CHLORIDE, G. SEPARATING SAID PRECIPTATED LIME FROM AT LEAST A PORTION OF SAID MOTHER LIQUOR, AND H. RECYCLING SAID PRECIPITATED LIME TO SAID MIXING ZONE.
Claim 22
Dependent Claim
56 words
The process of claim 1 wherein said moist cake of calcium hypochlorite dihydrate particles is heated to dry said particles, which after drying contain from about 0.5 to about 10 percent by weight of water and from about 65 to about 85 percent by weight of calcium hypochlorite, the bulk of the remainder being sodium chloride.
Claim 23
Dependent Claim
11 words
The process of claim 3 wherein said alkali metal is sodium.
Claim 24
Dependent Claim
39 words
The process of claim 4 wherein said mixing zone slurry has a lime concentration ranging from about 1 to about 25 percent by weight and a sodium hypochlorite concentration ranging from about 1 to about 25 percent by weight.
Claim 25
Dependent Claim
26 words
The process of claim 5 wherein the concentration of solid calcium hypochlorite dihydrate in said paste ranges from about 10 to about 30 percent by weight.
Claim 26
Dependent Claim
36 words
The process of claim 6 wherein said paste liquor has a concentration of sodium chloride ranging from about 15 to about 22 and a calcium hypochloride ranging from about 7 to about 15 percent by weight.
Claim 27
Dependent Claim
40 words
The process of claim 7 wherein said clarified mother liquor is an aqueous solution containing from about 15 to about 22 percent by weight of sodium chloride and from about 7 to about 20 percent by weight of sodium hypochlorite.
Claim 28
Dependent Claim
26 words
The process of claim 8 wherein said concentrated slurry of precipitated lime has a lime concentration ranging from about 25 to about 50 percent by weight.
Claim 29
Dependent Claim
78 words
The process of claim 9 wherein sufficient sodium hydroxide and chlorine are reacted with said clarified mother liquor and sufficient water is evaporated from said clarified mother liquor to form a salt slurry containing from about 15 to about 35 percent by weight of solid sodium chloride in an aqueous solution containing from about 15 to about 40 percent by weight of sodium hypochlorite and from about 4 to about 14 percent by weight of soluble sodium chloride.
Claim 30
Dependent Claim
18 words
The process of claim 10 wherein a portion of said paste liquor is recycled to said mixing zone.
Claim 31
Dependent Claim
42 words
The process of claim 11 wherein said calcium hypochlorite particles after drying contain from about 0.5 to about 8 percent water, from about 70 to about 80 percent by weight of calcium hypochlorite and the bulk of the remainder is sodium chloride.
Claim 32
Dependent Claim
35 words
The process of claim 12 wherein from about 25 to about 100 percent of fresh lime added to said process is first purified by chlorination and separation of insolubles before feeding to said mixing zone.
Claim 33
Dependent Claim
21 words
The process of claim 13 wherein all of said lime present in said mixing zone is added as said precipitated lime.
Claim 34
Dependent Claim
22 words
The process of claim 3 wherein said clarified mother liquor is simultaneously evaporated and reacted with said chlorine and said sodium hydroxide.
Claim 35
Dependent Claim
39 words
The process of claim 3 wherein evaporating and reacting of said clarified mother liquor is effected by first evaporating said clarified mother liquor and then reacting the resulting concentrated clarified mother liquor with said chlorine and said sodium hydroxide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-14 | 1979-01-13 | 1979-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-14 | 1983-01-13 | 1983-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-14 | 1987-01-13 | 1987-07-15 | $7700.00 | Window Closed / Lapsed |