Fremgangsmåte ved fremstilling av en prokatalysator for polymerisering av olefiner, samt anvendelse av denne

The invention relates to a process for preparation of a procatalyst for polymerization of olefins wherein a metal-containing complex compound or mixture of compounds is applicated into a porous, particulate carrier and is chlorinated with a suitable chlorinating agent. The invention also relates to the use of the prepared procatalyst composition together with a co-catalyst for polymerization or copolymerization of olefins. The invention is characterized in that magnesium or its compound, a titanium compound, aluminum or its compound and, optionally, a compound comprising a hydroxyl group are reacted with each other so that an alkoxide or alkylalkoxide solution containing said metals in an inert solvent is obtained, which solution is impregnated into the carrier at a single step, whereafter the extra solvent is removed. The carrier can be an inorganic oxide such as silica, from which the free hydroxyl groups have been removed, magnesium, titanium and aluminum compounds can be organic, the compound comprising a hydroxyl group can be an alcohol and the chlorination agent can be e.g. a suitable organic aluminum-chloride. The impregnated solution according to the invention can be provided by a simple mixing and the morphology and polymerization activity of the obtained procatalyst composition have proved to be good.