Claims
- 1. In a process for the preparation of a lower polyhydric alcohol by catalytic hydrogenolysis of sucrose in an aqueous medium, at elevated temperatures and pressures, the improvement for selectively producing ethylene glycol and 1,2-propylene glycol which comprises:
- using a catalyst in which the active material consists essentially of a reduced mixture of the oxides of the metals cobalt, copper and manganese, containing at least 5 up to not more than 80% by weight of manganese and up to not more than 85% by weight of copper, the percentages being based upon a total content of said metals of 100%, said catalyst being prepared by mixing the relevant metals in the form of their aqueous salt solutions and precipitating them together from this mixture by adding a base, then isolating and drying the precipitated material and converting the dried precipitate by calcination into a mixed oxide which is subsequently activated by reduction with hydrogen at an elevated temperature of at least about 200.degree. C.; and
- carrying out the hydrogenation reaction at a temperature of from 220.degree. C. to 280.degree. C. and at a hydrogen pressure of from 250 to 700 bar.
- 2. A process as claimed in claim 1, wherein the catalyst used is prepared by precipitating the salts of said metals with a water-soluble hydroxide or carbonate as the base, and subsequently converting the precipitate by calcination with air at 420.degree. C. to 550.degree. C. into a mixed oxide which is then activated by reduction with hydrogen at a temperature of from 200.degree. C. to 600.degree. C.
- 3. A process as claimed in claim 1, wherein the catalyst contains as the active metal component:
- from 5 to 90% by weight of cobalt;
- from 5 to 80% by weight of copper; and
- from 5 to 75% by weight of manganese.
- 4. A process as claimed in claim 1, carried out at a temperature of from 240.degree. C. to 270.degree. C.
- 5. A process as claimed in claim 1, carried out at a pressure of from 250 to 350 bar.
- 6. A process as claimed in claim 1, wherein the concentration of the sucrose in said aqueous medium is up to 70% by weight.
- 7. A process as claimed in claim 1, wherein the concentration of the sucrose in said aqueous medium is from about 30 to 60% by weight.
- 8. A process as claimed in claim 2, wherein the catalytic hydrogenolysis is carried out on an aqueous sucrose solution having a sucrose content of up to 70% by weight, at a temperature of 240.degree. C. to 270.degree. C., and at a pressure of from 250 to 350 bar.
Priority Claims (1)
Number |
Date |
Country |
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3818198.3 |
May 1988 |
DEX |
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Parent Case Info
This application is a continuation of application Ser. No. 785,223, filed Oct. 28, 1991, now abandoned, which in turn is a continuation of application Ser. No. 555,663, filed Jul. 18, 1990, now abandoned, which in turn is a continuation of application Ser. No. 385,545 filed May 26, 1989, now abandoned.
US Referenced Citations (11)
Non-Patent Literature Citations (4)
Entry |
Handbook of Chemistry & Physics, 32nd ed. (1950) pp. 1521 and 1522. |
G. V. Ling et al, Ind. Eng. Chem. Prod. Res. Develop., vol. 9, No. 2, 1970, pp. 210-212. |
G. Natta et al, Chem. Berichte 76 7 (1943) Table 1, pp. 641-657. |
R. Weidenhagen and H. Wegner, Chem. Ber. 71, 12 (1938), pp. 2712-2716. |
Continuations (3)
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Number |
Date |
Country |
Parent |
785223 |
Oct 1991 |
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Parent |
555663 |
Jul 1990 |
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Parent |
385545 |
May 1989 |
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