Method of catalytic polymeration of ethylene alone or common at least with one alpha-olefine

Ethylene polymerization catalysts are prepared by depositing a chromocene compound on a support with a titanium compound and activating the final blend at 300 DEG C. to about 1000 DEG C. A fluoriding agent can be optionally added where a narrower molecular weight distribution of the polyethylene to be obtained is desired. Catalysts with good reproducibility, when prepared by this method, show particular utility in production of polyethylene by a fluid bed process.