Patent ID: 7235703

Claim:
A catalytic composition comprising a product devoid of ethylene, propylene and butene, said product resulting from bringing the following three constituents into contact in any order: a) a least one divalent nickel compound of the formula (R 1 COO) 2 Ni where R 1 is an alkyl, cycloalkyl, alkenyl, aryl, aralkyl or alkaryl radical containing up to 20 carbon atoms; b) at least one hydrocarbylaluminum dihalide wherein said hydrocarbylaluminum dihalide further contains an aluminum trihalide, the mixture of these two compounds having formula AlR n X 3−n , R is a hydrocarbyl radical containing 1 to 12 carbon atoms and X is a chlorine or bromine atom and where n is a number between 0 and 1, 0 and 1 being excluded, and c) at least one organic Bronsted acid; and preconditioning a mixture of (a), (b) and (c) obtained in a solvent, in an inert atmosphere at a temperature of 0 to 80° C., for 1 minute to 5 hours.