Catalytic materials as for olefin polymerization

Claim 1

A process for the preparation of a catalyst material comprising coating a xerogel consisting of silica as the major constituent and having surface hydroxyl groups, a surface area in the range of 200 to 500 m 2 /g, a pore volume greater than about 2.0 cc/g, a major portion of which pore volume is provided by pores having pore diameters in the range of from 300 to 600 A with an aluminum compound capable of reacting with said surface hydroxyl groups and having the formula Al(X) a (OR) b , wherein X is R, a is 0-2, b is 1-3, a+b is 3, and R is an alkyl group having from 1 to 8 carbon atoms in an amount sufficient to provide from about 0.1 to 10% of aluminum by weight based on the weight of the xerogel, calcining the support material having the aluminum compound thereon at temperatures of at least 200° F., depositing on the aluminum coated calcined material an organophosphoryl chromium reaction product of chromium trioxide and an organophosphorus compound of the formula: ##STR3## wherein R is hydrogen, or alkyl, aralkyl, aryl, or cycloalkyl, but al least one R is other than hydrogen in an amount sufficient to provide from about 0.25 to 2.5% of chromium by weight based on the weight of the Xerogel; and activating the thus treated support in a non-reducing atmosphere at temperatures of from 1550° F. and up to the decomposition temperature of the support, said activating temperature being in excess of said calcining temperature.