Patent ID: 9120882
Filing Date: 2015-09-01
Classification: C08F,C08L

Abstract:
1. A process comprising: a) polymerizing propylene in a polymerization zone; b) withdrawing from said polymerization zone an effluent comprising polypropylene, propylene, propane and optionally a solvent; c) sending said effluent to a separation zone thereby producing polypropylene, optionally the solvent and a stream comprising propylene and propane; d) optionally recycling the solvent to the polymerization zone; e) sending said stream comprising propylene and propane to a splitter thereby producing an overhead consisting essentially of propylene recycled to the polymerization zone and a rich propane bottom stream comprising a minor part of propylene; f) sending the rich propane bottom stream to a membrane separation zone thereby producing a permeate having an enhanced propylene content and a reduced propane content and a purge having an enhanced propane content and a reduced propylene content; and g) recycling the permeate to the polymerization zone.