Process for producing a catalyst containing chromium

摘要

In accordance with a first embodiment of this invention, a silica xerogel is aqueously impregnated with a titanium compound which is resistant to hydrolysis. In accordance with a second embodiment of this invention, a silica hydrogel containing a titanium compound resistant to hydrolysis is dried. In this embodiment, the hydrogel preferably also contains a pore preserving agent. This invention makes possible the use of aqueous impregnation of titanium and conventional drying techniques to give a catalyst having characteristics associated with azeotrope dried silica-titanium coprecipitated catalyst. The catalysts of this invention are useful in olefin polymerization processes, particularly in the polymerization of predominantly ethylene monomer systems under slurry conditions.