Patent ID: 7141630
Filing Date: 2006-11-28
Classification: B01D,B01J,C08F,Y02P

Abstract:
1. A method of producing polypropylene polymers, comprising: contacting a first stream comprising propylene with or without one or more other olefins with at least one removal device to form a second stream comprising propylene with or without the one or more olefins, wherein the at least one removal device comprises molecular sieve particles having an average pore size of from 6 Å to 16 Å; contacting the second stream with a metallocene catalyst system to produce a third stream comprising one or more (co)polypropylenes and unpolymerized propylene and/or olefins; separating at least a portion of the un-polymerized propylene and/or olefins from the third stream to form a fourth stream comprising the at least a portion of the separated un-polymerized propylene and/or olefins; recovering polypropylene polymer(s) from the third stream, and combining the fourth stream with the first stream prior to contacting the first stream with the at least one removal device.