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US 4,788,171 AGranted
Phosphated calcined alumina
AssigneePhilips Petroleum Company
InventorDouglas D. Klendworth
Life of this patent
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Abstract
Alumina is calcined and thereafter given a phosphating treatment. The resulting composition is particularly suitable for a support for a transition metal compound such as chromium oxide to provide an olefin polymerization catalyst. The resulting catalyst is capable of producing polymer at unusually high productivity rates and also gives the ability to produce high melt flow polymer.
Claims16
A method of making a phosphated alumina comprising:
- (a) calcining alumina at a temperature of about 450.degree. C. to about 900.degree. C.;
- and
- (b) thereafter treating the thus calcined alumina with a phosphating agent selected from the group consisting of orthophosphoric acid, orthophosphates, POCl.sub.3, PCl.sub.3, phosphorous acid and NH.sub.4 H.sub.2 PO.sub.3 to give a surface treatment wherein the atom ratio P/Al is in the range of about 0.2:1 to 2:1.
Dependencies are inferred from the claim text.