Process for preparing polymerization catalyst carrier by spray crystallization in an electric field

Abstract

The present invention is directed to a method for preparing particulate carriers for olefin polymerization procatalysts in which: (a) a heated melt of a complex compound is provided having the formula I MgCl.sub.2.nROH.mED (I) in which ROH is a lower (C.sub.1-6) aliphatic alcohol, ED is an electron donor, n is 1 to 6 and m is 0 to 1, (b) the heated melt is fed to a nozzle atomizing it, (c) the melt to be atomized is sprayed from the nozzle into a chamber, where it is distributed in the form of an atomized melt and then solidified to from fine carrier particles and (d) the fine carrier particles are recovered. During this process an electric charge is fed into the melt to be atomized or which has been atomized, which decreases the surface tension of the solidified melt and prevents the agglomeration of the formed droplets. The charge can be achieved by arranging in connection with the nozzle an electrode, which together with, for example, the grounded melt, forms a static electric couple.

Dependencies are inferred from the claim text.