US3846460A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing copper oxalate
Assignee: Cities Service Co
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Filing: 1973-04-25
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Granted: 1974-11-05
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Expires: 1993-04-25
Abstract
Abstract A ferrous salt is reacted with a soluble oxalate to yield ferrous oxalate which is subsequently slurried with a copper salt to produce copper oxalate. This improved process for manufacturing copper oxalate yields a copper oxalate which is easily separated by filtration in substantially pure form; it is readily washable and dries as a very fine powder that requires no grinding.
Inventors
- 👤 C Fite
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:16
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/41; C07C51/412
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
78 words
AN IMPROVED PROCESS FOR THE MANUFACTURE OF COPPER OXALATE COMPRISING: A. REACTING AN AQUEOUS FERROUS SALT SOLUTION WITH A SOLUBLE OXALATE TO PRECIPITATE FERROUS OXALATE; B. SEPARATING FERROUS OXALATE OF STEP (A) FROM THE RESULTING SLURRY; C. SLURRYING FERROUS OXELATE OF STEP (B) IN A SOLUTION OF A WATER-SOLUBLE COPPER SALT TO YIELD COPPER OXALATE AND A SOLUTION OF A FERROUS SALT; AND D. FILTERING THE COPPER OXALATE OF STEP (C) FROM THE SOLUTION OF SAID FERROUS SALT.
Claim 2
Dependent Claim
78 words
AN IMPROVED PROCESS FOR THE MANUFACTURE OF COPPER OXALATE COMPRISING: A. REACTING AN AQUEOUS FERROUS SALT SOLUTION WITH A SOLUBLE OXALATE TO PRECIPITATE FERROUS OXALATE; B. SEPARATING FERROUS OXALATE OF STEP (A) FROM THE RESULTING SLURRY; C. SLURRYING FERROUS OXELATE OF STEP (B) IN A SOLUTION OF A WATER-SOLUBLE COPPER SALT TO YIELD COPPER OXALATE AND A SOLUTION OF A FERROUS SALT; AND D. FILTERING THE COPPER OXALATE OF STEP (C) FROM THE SOLUTION OF SAID FERROUS SALT.
Claim 3
Dependent Claim
24 words
The method according to claim 1 including the additional step of washing the filtered copper oxalate of step (d) to remove any soluble materials.
Claim 4
Dependent Claim
17 words
The method according to claim 1 in which the ferrous salt of step (a) is ferrous sulfate.
Claim 5
Dependent Claim
17 words
The method according to claim 1 in which the soluble oxalate of step (a) is oxalic acid.
Claim 6
Dependent Claim
17 words
The method according to claim 1 in which the copper salt of step (c) is copper sulfate.
Claim 7
Dependent Claim
28 words
The method according to claim 1 in which the reacting solutions in step (a) are mildly agitated from about 5 to about 15 minutes to insure complete reaction.
Claim 8
Dependent Claim
25 words
The method according to claim 1 in which the soluble oxalate of step (a) is reacted with a slight stoichiometric excess of a ferrous salt.
Claim 9
Dependent Claim
27 words
The method according to claim 1 in which the ferrous oxalate of step (c) is slurried in a solution containing a stoichiometric excess of a copper salt.
Claim 10
Dependent Claim
30 words
The method according to claim 1 in which the slurrying of ferrous oxalate of step (c) in a solution of soluble copper salt is mildly agitated for approximately 2 hours.
Claim 11
Dependent Claim
22 words
The method according to claim 1 in which the filtered copper oxalate of step (d) comprises less than about 0.1% wt. iron.
Claim 12
Dependent Claim
40 words
The method according to claim 1 in which the copper oxalate of step (d) is filtered from the solution of ferrous salt, and said solution of ferrous salt is recycled to react with soluble oxalate to precipitate more ferrous oxalate.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-04 | 1978-05-06 | 1978-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-04 | 1982-05-06 | 1982-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-04 | 1986-05-06 | 1986-11-05 | $7700.00 | Window Closed / Lapsed |