Patent ID: 7235614
Filing Date: 2007-06-26
Classification: B01J,C08F,Y10S

Abstract:
1. A method of forming polypropylene, comprising; providing a conduit having a catalyst inlet, a first propylene stream inlet and a second propylene stream inlet located downstream of the first propylene stream inlet, the conduit being operably connected to a polymerization vessel; introducing a catalyst to the conduit through the catalyst inlet; combining a first propylene stream with the catalyst to provide a mixed catalyst stream; passing the mixed catalyst steam though the conduit to the polymerization vessel; introducing a second propylene stream to the conduit through the second propylene stream inlet; stopping the flow of the catalyst passing through the conduit; removing a first section of the conduit; and replacing the first section of the conduit with a second conduit section, wherein the removing and replacing steps are conducted while polymerization occurs in the polymerization vessel.