Patent US4902823A successfully refreshed from Google Patents.
US4902823A
Expired / Lapsed
US
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Process for the preparation of vinyl acetate
Assignee: Celanese Sales Germany GmbH
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Filing: 1989-02-07
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Granted: 1990-02-20
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Expires: 2009-02-07
Abstract
Abstract The invention relates to a process for the preparation of vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases on a catalyst which contains palladium and/or compounds thereof and if appropriate additionally gold and/or gold compounds and, as activators, alkali metal compounds and if appropriate additionally cadmium compounds, on a support. The support consists of cylindrical particles with curved front faces. The support material is aerogenic SiO 2 or an aerogenic SiO 2 -Al 2 O 3 mixture having a surface area of 50-250 m 2 /g and a pore volume of 0.4-1.2 ml/g, which is formed to the extent of at least 50% by pores having a diameter of 50-200 Å.
Inventors
- 👤 Friedrich Wunder
- 👤 Gunter Roscher
- 👤 Klaus Eichler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:07
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/38; B01J23/48; B01J23/52; C; C07; C07C; C07C67/00; C07C67/04; C07C67/05; C07C67/055; B01J35/00; B01J35/50; B01J35/55; B01J35/60; B01J35/61; B01J35/613; B01J35/615; B01J35/63
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
113 words
A process for the preparation of vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases on a catalyst which contains palladium and/or compounds thereof and optionally gold and/or gold compounds and, as activators, alkali metal compounds and if optionally cadmium compounds, on a support which consists of aerogenic SiO 2 or an aerogenic SiO 2 -Al 2 O 3 mixture having a surface area of 50-250 m 2 /g and a pore volume of 0.4-1.2 ml/g, the pore volume being formed to the extent of at least 50% by pores having a diameter of 50-200 Angstroms, wherein the support consists of cylindrical particles having curved front faces.
Claim 2
Dependent Claim
113 words
A process for the preparation of vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases on a catalyst which contains palladium and/or compounds thereof and optionally gold and/or gold compounds and, as activators, alkali metal compounds and if optionally cadmium compounds, on a support which consists of aerogenic SiO 2 or an aerogenic SiO 2 -Al 2 O 3 mixture having a surface area of 50-250 m 2 /g and a pore volume of 0.4-1.2 ml/g, the pore volume being formed to the extent of at least 50% by pores having a diameter of 50-200 Angstroms, wherein the support consists of cylindrical particles having curved front faces.
Claim 3
Dependent Claim
50 words
The process as claimed in claim 1, wherein the cylindrical particles with a curved front face have a radius of 2-8 mm and a length, including the curved front faces, of 2-15 mm, the height of each of the two curved front faces being 0.2 times to once the radius.
Claim 4
Dependent Claim
50 words
The process as claimed in claim 1, wherein the cylindrical particles with a curved front face have a radius of 2-4 mm and a length, including the curved front faces, of 6-15 mm, the height of each of the two curved front faces being 0.2 times to once the radius.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-02-19 | 1993-08-21 | 1994-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-19 | 1997-08-21 | 1998-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-19 | 2001-08-21 | 2002-02-20 | $7700.00 | Window Closed / Lapsed |