Chromium phyllosilicate clay α-olefin catalysts

Abstract

A process for preparing pillared chromium phyllosilicate clay α-olefin catalysts is disclosed. This process utilizes palygorskite and sepiolite clays. The pillaring of said clays comprises the steps of: (a) preparing a hydrolyzed first solution by dissolving a chromium salt and a base in water, heating said first solution to a temperature in the range of about 20° C. to about 100° C. while stirring continuously until the solution reaches a pH in the range of about 1.5 to about 2.5 and thereby producing a master batch; (b) diluting said master batch with water to produce a diluted second solution and heating said diluted second solution to produce a heated second solution; (c) adding a solid clay selected from the group consisting of sepiolites and palagorskites to said heated second solution, and continuing heating; (d) recovering said pillared chain silicate clay; and (e) drying said pillared chain silicate clay to form first product. The activation of said clays comprise the steps of: (a) heating said first product at a temperature in the range of about 150° C. to about 500° C. and for a time period in the range of about 30 minutes to about 10 hours in an inert atmosphere; (b) thereafter reheating said first product at a temperature in the range of about 500° C. to about 900° C. and for a time period in the range of about 1 hour to about 50 hours in an oxidizing atmosphere and recovering said catalyst composition. This results in clay catalysts which polymerize alpha-olefins.

Dependencies are inferred from the claim text.