Process for the production of a microspheroidal powder of low dispersity, microspheroidal powder of low dispersity thus obtained, catalysts for the polymerization of alpha-olefins and process for the polymerization of alpha-olefins

摘要

Process for the production of a microspheroidal powder of low dispersity, according to which a hydrogel is prepared, an aqueous suspension of the ground hydrogel is subjected to atomisation in a stream of gas, gelled particles containing moisture are collected from the atomisation, the particles are brought into contact with an organic liquid in order to remove at least some of the moisture and the particles are then subjected to drying. The process applies to the production of silica powders intended to serve as support for chromium oxide catalysts which may contain titanium oxide and are suitable for the polymerisation of ethylene.