Claims
- 1. In a process for the preparation of vinyl acetate in the gaseous phase by reacting ethylene with acetic acid and oxygen or oxygen-containing gases in the presence of a catalyst containing a noble metal of sub-group VIII of the periodic table, or a compound thereof, and as an activator an alkali metal compound, an alkaline earth metal compound or a cadmium compound, or any combination thereof, the improvement which comprises applying said noble metal and said activator onto a carrier consisting essentially of particles of silicic acid having a star-shaped cross section with a core portion and at least 3 star points with a core diameter in the range of 2 mm to 4 mm, an average radius of 1.5 mm to 7.5 mm as measured by the distance from the center of the core portion to the apex of a star point and an average indentation in the range of 0.5 mm to 6.5 mm as measured by the distance from the outer surface of the core portion to the apex of a star point.
- 2. The process of claim 1 wherein the catalyst additionally contains gold or a compound thereof.
- 3. The process of claim 1 wherein the noble metal is palladium, or a compound thereof, present at a concentration in the range of from 0.5% to 5% by weight of the catalyst.
- 4. The process of claim 1 wherein the catalyst contains palladium, or a compound thereof, an alkali metal and cadmium.
- 5. The process of claim 1 wherein the catalyst contains palladium, or a compound thereof, an alkali metal and gold, or a compound thereof.
- 6. The process of claim 4 or 5 wherein the alkali metal is potassium in the form of a carboxylate.
- 7. The process of claim 1 wherein the catalyst contains palladium acetate, potassium acetate and cadmium acetate or palladium acetate, barium acetoaurate and potassium acetate.
- 8. The process of claim 1 wherein the activator is present at a concentration in the range of from 0.01% to 4% by weight, the percentage indicating the metal proportion of the activator being calculated on the total amount of carrier catalyst.
- 9. The process of claim 1 wherein said carrier is a four to six pointed star.
- 10. The process of claim 1 wherein the indentation is in the range of 1 mm to 2.5 mm.
- 11. The process of claim 1 wherein the radius is in the range of 2 mm to 3.5 mm.
- 12. In a process for the preparation of vinyl acetate in the gaseous phase by reacting ethylene with acetic acid and oxygen or oxygen-containing gases in the presence of a catalyst containing a noble metal of sub-group VIII of the periodic table, or a compound thereof, and as an activator an alkali metal compound, an alkaline earth metal compound or a cadmium compound, or any combination thereof, the improvement which comprises applying palladium, cadmium acetate and potassium acetate onto a carrier consisting essentially of particles of silicon dioxide having a star-shaped cross section with a core portion and 5 star points with an average radius of 2 mm to 3.5 mm as measured from the center of said core portion to the apex of a star point and an average indentation in the range of 1 mm to 2.5 mm as measured by the distance from the outer surface of the core portion to the apex of a star point.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2811115 |
Mar 1978 |
DEX |
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Parent Case Info
This is a division of application Ser. No. 20,038 filed Mar. 13, 1979.
US Referenced Citations (5)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1296198 |
May 1969 |
DEX |
Non-Patent Literature Citations (1)
Entry |
Emmett, "Catalysis", vol. II, pp. 124-137 (1958). |
Divisions (1)
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Number |
Date |
Country |
Parent |
20038 |
Mar 1979 |
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