PROCESS FOR MULTI-STEP GAS-PHASE POLYMERIZATION OF OLEFINS

摘要

A process for polymerizing olefins in the gaseous phase in separate first and second gas-phase polymerization zones, in the presence of a catalyst composed of a transition metal catalyst component and an organo-metallic compound of a metal of Groups I to III of the periodic table while feeding the catalyst-containing polymer formed in the first zone to the second zone through a feed passage, wherein
[i] a suspension zone is provided in the feed passage for forming a suspension of the polymer from the first zone in an easily volatile hydrocarbon medium which is liquid under the conditions of feeding the polymer; and
[ii] the suspension formed in the suspension zone is fed to the second zone.