Claims
- 1. In the method of purifying substituted 1,3-diols having the general formula ##STR3## prepared by aldolization reactions with ensuing hydrogenation to form a crude product having a given positive saponification number according to the following equation: ##STR4## wherein R=alkyl or hydrogen, and R.sup.1 =alkyl, the improvement comprising:
- (a) treating said crude product at an elevated temperature with at least sufficient basic additive to reduce said saponification number to zero and produce a saponified product;
- (b) mixing said saponified product with about 5 to 30% water by weight and forming first aqueous and first organic phases;
- (c) mechanically separating said first aqueous phase from said first organic phase;
- (d) adding about 5 to 30% water by weight to said first organic phase, adjusting the resulting mixture to a pH of 8.0 to 10.5 and forming second aqueous and organic phases;
- (e) mechanically separating said second aqueous phase from said second organic phase;
- (f) separating monovalent alcohol by-product from said second organic phase by distillation;
- (g) adjusting the pH value of said monovalent alcohol free second organic phase to 8.0 to 10.5; and
- (h) recovering said substituted 1,3-diols by fractional distillation.
- 2. The method of claim 1, wherein step (b) further comprises cooling to 1.degree. to 30.degree. C.
- 3. The method of claim 2, wherein step (d) has a pH of 8.5 to 9.5.
- 4. The method of claim 3, wherein step (g) has a pH of 8.5 to 9.5.
- 5. The method of claim 2, wherein step (g) has a pH of 8.5 to 9.5.
- 6. The method of claim 1, wherein said elevated temperature of step (a) is 80.degree. to 130.degree. C.
- 7. The method of claim 6, wherein said basic additive is selected from the group consisting of alkali hydroxides, alkali earth hydroxides, ammonia and amines.
- 8. The method of claim 7, wherein said basic additive has a concentration of 10 to 50% by weight in water.
- 9. The method of claim 6, wherein said substituted 1,3-diols are selected from the group consisting of 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexanediol and 2-propyl-1,3-heptanediol.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3432719 |
Sep 1984 |
DEX |
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Parent Case Info
This application is a continuation-in-part of application Ser. No. 747,848, filed June 24, 1985, now abandoned.
US Referenced Citations (7)
Continuation in Parts (1)
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Number |
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747848 |
Jun 1985 |
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