US 12,110,359 B2
Continuous process for metallocene preliminary polymerization for gas-phase polymerization process
Olavo Martins Junior, São Paulo (BR); Fabio Andre Kunrath, São Paulo (BR); and Márcia Silva Lacerda Miranda, São Paulo (BR)
Assigned to Braskem S.A., Camaçari (BR)
Filed by Braskem S.A., Camaçari (BR)
Filed on Jul. 15, 2022, as Appl. No. 17/866,410.
Claims priority of provisional application 63/222,310, filed on Jul. 15, 2021.
Prior Publication US 2023/0036349 A1, Feb. 2, 2023
Int. Cl. C08F 4/6592 (2006.01); C08F 4/14 (2006.01); C08F 4/659 (2006.01); C08F 210/02 (2006.01); C08F 210/16 (2006.01)
CPC C08F 4/14 (2013.01) [C08F 4/65916 (2013.01); C08F 210/02 (2013.01); C08F 210/16 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A process for preliminary polymerization, comprising:
washing a catalyst mud comprising a supported metallocene catalyst with a solvent at a temperature from 0° C. to 40° C., a pressure from 20 to 40 kgf/cm2, and a residence time of at least 30 minutes;
continuously feeding the washed catalytic mud to a continuous pre-polymerization reactor; and
pre-polymerizing, in the continuous pre-polymerization reactor, ethylene and at least one C4 to C10 α-olefin as comonomer, with the washed catalytic mud, in the presence of an inert diluent, to produce a pre-polymer.