Florided aluminas, catalysts, and polymerization processes

摘要

High surface are aluminas are pre-calcined to form gamma-alumina. In one embodiment, the gamma-alumina is treated with an anhydrous solution of a fluorine-containing compound. In a second embodiment, alumina is precipitated in the pores of the gamma-alumina and then treated with a fluorine-containing compound. In a third embodiment a cogel of aluminum trifluoride and aluminum hydroxide is prepared. The three inventive fluorided alumina supports can be impregnated with a transition metal, preferably chromium, to form a catalyst system which can be used to polymerize mono-1-olefins.