US3862219A
Expired / Lapsed
US
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Process for the preparation of alkali-metal salts of carboxyalkoxy succinates
Assignee: Ethyl Corp
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Filing: 1971-10-20
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Granted: 1975-01-21
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Expires: 1991-10-20
Abstract
Abstract It is disclosed that high purity alkali metal salts of carboxyalkoxy succinic acid are produced from maleic acid and a hydroxy organic acid by reaction of zinc or alkaline earth metal salts of said acids to form a zinc or alkaline earth metal carboxyalkoxy succinate, by reacting the zinc or alkaline earth metal carboxyalkoxy succinate with an alkali metal carbonate in a stoichiometric deficiency of carbonate to selectively react with the alkaline earth metal carboxyalkoxy succinate, leaving the impurities as insoluble alkaline earth metal salts, removing the zinc or alkaline earth metal as insoluble carbonate, and recovering an alkali metal carboxyalkoxy succinate solution which is then evaporated to dryness.
Inventors
- 👤 Kenneth L Lindsay
- 👤 Paul Kobetz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:53
CPC Classifications
C; C07; C07C; C07C59/00; C07C59/235; C07C59/305; C07C59/01
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
45 words
A process as in claim 1 wherein the zinc or alkaline earth metal carboxyalkoxy succinate is produced by a reaction of zinc or alkaline earth metal salts of glycolic acid and maleic acid at a pH of at least about 8 as measured at 25*C.
Claim 2
Dependent Claim
54 words
A process as in claim 1 wherein the zinc or alkaline earth metal carboxyalkoxy succinate is produced by a reaction of calcium glycolate and calcium maleate at a pH of at least about 8 as measured at 25*C to form carboxymethoxy succinic acid, calcium salt, contaminated with calcium glycolate, calcium maleate and calcium fumarate.
Claim 3
Dependent Claim
49 words
A process of claim 1 wherein the alkali metal carbonate is sodium carbonate and the amount used is from about 25 to about 100 percent of the stoichiometric amount required to react selectively to convert the zinc or alkaline earth metal carboxyalkoxy succinate present to alkali metal carboxyalkoxy succinate.
Claim 4
Dependent Claim
48 words
A process in claim 1 wherein the alkali metal carbonate is sodium carbonate and the amount is from about 50 to about 90 percent of the stoichiometric amount required to react selectively to convert the zinc or alkaline earth metal carboxyalkoxy succinate present to alkali metal carboxyalkoxy succinate.
Claim 5
Dependent Claim
48 words
A process in claim 1 wherein the alkali metal carbonate is sodium carbonate and the amount is from about 60 to about 80 percent of the stoichiometric amount required to react selectively to convert the zinc or alkaline earth metal carboxyalkoxy succinate present to alkali metal carboxyalkoxy succinate.
Claim 6
Dependent Claim
44 words
A process as in claim 1 wherein the alkali metal carbonate is sodium carbonate and it is reacted with carboxymethoxy succinic acid, calcium salt to produce carboxymethoxy succinic acid, sodium salt at a temperature of from about 70* to about 100* precipitating calcium carbonate.
Claim 7
Dependent Claim
26 words
A process as in claim 1 wherein the purified alkali metal carboxyalkoxy succinate solution is dried at a temperature of from about 25* to about 150*C.
Claim 8
Dependent Claim
27 words
A process as in claim 1 wherein the water is evaporated from the alkali metal carboxymethoxy succinate at a temperature of from about 25* to about 50*C.
Claim 9
Dependent Claim
32 words
A process as in claim 1 wherein the alkaline earth metal carboxyalkoxy Succinate is washed with water at a temperature of from about 50* to about 100*C prior to the selective reaction.
References Cited (Backward Citations)
US3692685A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |