Preparation of a supported catalyst for the polymerization of .alpha.-olefins

US5625013A · kind A · utility

Assignee

• BASF SE

Inventors

• Hans-Joachim Mueller · Havelsee, DE
• Godofredo Follmer · Frankenthal (Pfalz), DE
• Rainer Konrad · Putlitz, DE
• Roland Saive · Ludwigshafen, DE
• Martin Lux · Schifferstadt, DE
• Hans-Helmut Goertz · Ludwigshafen, DE
• Guido Funk · Worms, DE

Key dates

• Filing date: May 24, 1995
• Grant date: Apr 29, 1997
• Expiry date: May 24, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F10/00
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for the preparation of a supported catalyst for the polymerization of .alpha.-olefins, in which PA1 (1) a silicon dioxide-containing support gel is prepared by PA2 (1.1) introducing a sodium water glass or potassium water glass solution into a swirling stream of an aqueous mineral acid longitudinally and tangentially to the stream, spraying the resultant silica hydrosol in drop form into a gaseous medium and allowing it to solidify to form a hydrogel, and freeing the resultant hydrogel from salts by washing without prior ageing, PA2 (1.2) drying the hydrogel resulting from (1.1) to form the support gel, PA1 (2) the support gel (1) is charged with chromium trioxide or a chromium compound which can be converted into chromium trioxide under the conditions of process step (3), giving a chromium-containing support gel, and PA1 (3) the chromium-containing support gel (2) is heated at from 400.degree. to 1100.degree. C. for from 10 to 1000 minutes in an anhydrous gas stream containing oxygen in a concentration of greater than 10% by volume, comprises drying the hydrogel resulting from step (1.1) in step (1.2) within a time of not more than 60 seconds in a shaping, high-speed dry…