US4272448A
Expired / Lapsed
US
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Process for the manufacture of aluminum monoethyl phosphite
Assignee: Bayer CropScience SA
•
Filing: 1979-06-25
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Granted: 1981-06-09
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Expires: 1999-06-25
Abstract
Abstract Aluminum monoethyl-phosphite, useful for the protection of plants against fungal diseases, is manufactured in a continuous manner by first preparing a mixture of phosphite compounds, containing at least 70 mol % of diethyl phosphite, then saponifying and neutralizing such mixture with an inorganic base, at a temperature of 20°-85° C., at a pH of 4.0-8.5, and finally reacting the residual aqueous solution of alkaline metal monoethyl-phosphite, continuously withdrawn from the preceding operation, with an approximately stoichiometric amount of a water-soluble aluminum salt at 70°-95° C. and a pH of 3.0-4.5.
Inventors
- 👤 Andre Bernard
- 👤 Andre Disdier
- 👤 Michel Royer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:56
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/02; C07F9/06; C07F9/08; C07F9/141; C07F9/142
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
110 words
A process for the continuous manufacture of aluminium monoethyl-phosphite, which consists in successively: (a) preparing a mixture of phosphite compounds, containing at least 70 mol % of diethyl phosphite, (b) saponifying and neutralising this mixture with an inorganic base at a temperature of 20° to 85° C., whilst keeping the pH at 4.0 to 8.5, and then (c) reacting the residual aqueous solution of alkali metal monoethyl-phosphite, which is continuously withdrawn from the preceding operation, with an approximately stoichiometric amount of a water-soluble aluminium salt, at a temperature of 70° to 95° C. and at a pH of about 3.0 to 4.5, and continuously withdrawing the precipitate of aluminium monoethyl-phosphite.
Claim 2
Dependent Claim
110 words
A process for the continuous manufacture of aluminium monoethyl-phosphite, which consists in successively: (a) preparing a mixture of phosphite compounds, containing at least 70 mol % of diethyl phosphite, (b) saponifying and neutralising this mixture with an inorganic base at a temperature of 20° to 85° C., whilst keeping the pH at 4.0 to 8.5, and then (c) reacting the residual aqueous solution of alkali metal monoethyl-phosphite, which is continuously withdrawn from the preceding operation, with an approximately stoichiometric amount of a water-soluble aluminium salt, at a temperature of 70° to 95° C. and at a pH of about 3.0 to 4.5, and continuously withdrawing the precipitate of aluminium monoethyl-phosphite.
Claim 3
Dependent Claim
42 words
A process according to claim 1, which comprises starting from a mixture of phosphite compounds containing at least 70 mol % of diethyl phosphite, from 1 to 25 mol% of monoethyl phosphite and from 0 to 2 mol % of phosphorous acid.
Claim 4
Dependent Claim
30 words
A process according to claim 2, in which the mixture of phosphite compounds is obtained by reaction of phosphorus trichloride and ethanol at a temperature between 30° and 80° C.
Claim 5
Dependent Claim
19 words
A process according to claim 3, in which the ethanol employed contains at most 15% by weight of water.
Claim 6
Dependent Claim
28 words
A process according to claim 3, in which the mixture of phosphite compounds is then freed of the hydrochloric acid produced by the reaction for obtaining this mixture.
Claim 7
Dependent Claim
47 words
A process according to claim 2, in which the mixture of phosphite compounds is obtained by the reaction, at a temperature of about 150° C., of a binary mixture containing at least 85 mol % of diethyl phosphite and at most 15 mol % of phosphorous acid.
Claim 8
Dependent Claim
23 words
A process according to one of claims 1 to 6, which comprises using sodium hydroxide, potassium hydroxide or ammonia as the inorganic base.
Claim 9
Dependent Claim
37 words
A process according to claim 1, in which the saponification and neutralisation reaction is carried out continuously in a reactor, at a pH between about 7 and 8 and at a temperature of 65° to 85° C.
Claim 10
Dependent Claim
64 words
A process according to claim 1, in which the saponification and neutralisation reaction is carried out continuously in two stages, the first being at a temperature of 30° to 60° C. and at a pH equal to at most 4.5, and in which the reaction is completed at a pH equal to at most 8.5 and at a temperature of 60° to 85° C.
Claim 11
Dependent Claim
29 words
A process according to claim 1, in which the ethanol produced by the saponification and the neutralisation is removed continuously by distillation in the form of an aqueous-alcoholic mixture.
Claim 12
Dependent Claim
25 words
A process according to claim 10, in which the aqueous-alcoholic mixture separated off by distillation is recycled continuously into the first stage of the process.
Claim 13
Dependent Claim
28 words
A process according to claim 1, in which the double decomposition is carried out starting from an excess of up to 20 mol % of water-soluble aluminium salt.
Claim 14
Dependent Claim
21 words
A process according to claim 12, which comprises employing an excess, ranging up to 10 mol %, of water-soluble aluminium salt.
Claim 15
Dependent Claim
11 words
A process according to claim 1, which comprises employing aluminium sulphate.
Claim 16
Dependent Claim
16 words
A process according to claim 14, in which the aluminium sulphate is added as a solid.
Claim 17
Dependent Claim
17 words
A process according to claim 14, in which the aluminium sulphate is added as an aqueous solution.
Claim 18
Dependent Claim
11 words
A process according to claim 13, which comprises employing aluminium nitrate.
Claim 19
Dependent Claim
24 words
A process according to claim 13, which comprises using an alkali metal aluminate and adding a strong acid to a pH of about 4.
Claim 20
Dependent Claim
22 words
A process according to claim 1, which comprises adding a water-soluble inorganic salt to the reaction medium in the double decomposition stage.
Claim 21
Dependent Claim
15 words
A process according to claim 19, in which the water-soluble inorganic salt is sodium sulphate.
Claim 22
Dependent Claim
134 words
A process of making aluminium monoethyl-phosphite comprising (a) providing a mixture of at least 70 mol % diethyl phosphite, 1-25% monoethyl phosphite and 0-2% phosphorous acid; (b) continuously saponifying the diethyl phosphite and neutralizing the monoethyl phosphite and acid with a 20-50% aqueous solution of strong inorganic base for about 1-6 hours at 30°-85° C. and a pH of 4.0-8.5, and continuously distilling of ethanol formed during said saponifying and neutralizing stage and thereby providing an aqueous solution of about 20-70% Me monoethyl phosphite; (c) continuously subjecting said aqueous solution of Me monoethyl phosphite to double decomposition by reaction with up to 20 mol % excess of water-soluble aluminum salt at 70°-95° C. and pH 3.0-4.5 for at least 30 minutes to form aluminum monoethyl phosphite precipitate; and (d) recovering and washing the precipitate.
Claim 23
Dependent Claim
134 words
A process of making aluminium monoethyl-phosphite comprising (a) providing a mixture of at least 70 mol % diethyl phosphite, 1-25% monoethyl phosphite and 0-2% phosphorous acid; (b) continuously saponifying the diethyl phosphite and neutralizing the monoethyl phosphite and acid with a 20-50% aqueous solution of strong inorganic base for about 1-6 hours at 30°-85° C. and a pH of 4.0-8.5, and continuously distilling of ethanol formed during said saponifying and neutralizing stage and thereby providing an aqueous solution of about 20-70% Me monoethyl phosphite; (c) continuously subjecting said aqueous solution of Me monoethyl phosphite to double decomposition by reaction with up to 20 mol % excess of water-soluble aluminum salt at 70°-95° C. and pH 3.0-4.5 for at least 30 minutes to form aluminum monoethyl phosphite precipitate; and (d) recovering and washing the precipitate.
References Cited (Backward Citations)
US4139616A
Cited
US4143059A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-06-08 | 1984-12-08 | 1985-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-08 | 1988-12-08 | 1989-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-08 | 1992-12-08 | 1993-06-09 | $7700.00 | Window Closed / Lapsed |