Process for preparing solid support for procatalyst for polymerization of olefins

A process for the preparation of a solid support for a procatalyst suitable for the preparation of a catalyst composition for the polymerization of olefins, said process comprising: A. providing or preparing a compound R4 zMgX 42-z wherein: R4 is independently selected from a linear, branched or cyclic hydrocarbyl group; the alkyl is independently selected from alkyl, alkenyl, aryl, aralkyl or alkylaryl and one or more combinations thereof; x4 is independently selected from fluorine ions, chloride ions, bromide ions or iodide ions; and 0 lt; zlt, zlt; 2; and B. contacting the compound R4 zMgX42-z with a silane compound Si (OR5) 4-n (R6) n to produce Mg (OR1) xX12-x wherein: R1, R5 and R6 are each independently selected from a linear, branched or cyclic hydrocarbyl group, which is independently selected from an alkyl, alkenyl, aryl, aralkyl, alkoxycarbonyl or alkylaryl group, and one or more combinations thereof; the part 1 is independently selected from fluorine ions, chloride ions, bromide ions or iodide ion