Catalyst compositions and catalytic processes
AssigneePhillips Petroleum Company
InventorRickey D. Badley
Life of this patent
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Abstract
Catalyst compositions are provided that comprise (a) discrete silica particles; (b) chromium; and (c) a support comprising silica. These composition are useful in polymerizing ethylene or copolymerizing ethylene with a comonomer and provide better control over the molecular weight and the molecular weight distribution of a resulting polymer.
Claims9
A process comprising homopolymerizing ethylene or copolymerizing ethylene and a comonomer with a catalyst composition comprising:
- (a) discrete silica particles, wherein said discrete silica particles are produced by the process consisting essentially of contacting together, in the absence of an acid, a tetraalkoxysilane composition, an alcohol composition, an ammonia composition, and water;
- (b) chromium;
- and
- (c) a support that comprises silica.
A process comprising homopolymerizing ethylene or copolymerizing ethylene and a comonomer with a catalyst composition that is produced by a process comprising:
- (a) producing a mixture that comprises discrete silica particles and chromium wherein said discrete silica particles are produced by the process consisting essentially of contacting together, in the absence of an acid, a tetraalkoxysilane composition, an alcohol composition, an ammonia composition, and water;
- (b) contacting said mixture with a composition that comprises
- (1) chromium and
- (2) a support that comprises silica to form said catalyst composition.
A process comprising homopolymerizing ethylene or copolymerizing ethylene and a comonomer with a catalyst composition that is produced by a process comprising:
- (a) producing a mixture that comprises discrete silica particles, wherein said discrete silica particles are produced by the process consisting essentially of contacting together, in the absence of an acid, a composition, and water;
- and then
- (b) contacting said mixture with a support that comprises silica to form a composition that comprises said discrete silica particles and said support;
- and then
- (c) contacting said composition that comprises said discrete silica particles and said support with chromium to form said catalyst composition.
Dependencies are inferred from the claim text.