| 摘要 |
Frangible, spray dried agglomerate catalyst supports are provided, e.g. of silica gel, which possess a controlled morphology of microspheroidal shape, rough, scabrous appearance, and interstitial void spaces which penetrate the agglomerate surface and are of substantially uniform size and distribution. The agglomerates also possess a 1-250 micron particle size, 1-1000 m<2>/gm. surface area, and an Attrition Quality Index (AQI) of at least 10. The agglomerates are derived from a mixture of dry milled inorganic oxide particles, e.g. silica gel, and optionally but preferably wet milled inorganic oxide particles, e.g. silica gel particles, (which preferably contain a colloidal segment of < 1 micron particles) slurried in water for spray drying. The high AQI assures that the agglomerates are frangible and that polymerization performance is improved. The controlled morphology is believed to permit the constituent particles of the agglomerates to be more uniformly impregnated or coated with conventional olefin polymerization catalysts. |
