Univation Technologies, LLC

Disclosed herein is a method for polymerizing a compound in a gas phase reactor. The method includes at least passing a liquid catalyst to a catalyst inlet of a manifold assembly, passing a carrier gas to a carrier gas inlet of the manifold assembly, combining the liquid catalyst and the carrier gas in the main channel of the manifold assembly, and passing the combination of the liquid catalyst and the carrier gas to the reaction chamber. The present disclosure is also directed to manifold assemblies for communication with reaction chambers.

Methods and systems for olefin polymerization are provided. The method for olefin polymerization can include flowing a catalyst through an injection nozzle and into a fluidized bed disposed within a reactor. The method can also include flowing a feed comprising one or more monomers, one or more inert fluids, or a combination thereof through the injection nozzle and into the fluidized bed. The feed can be at a temperature greater than ambient temperature. The method can also include contacting one or more olefins with the catalyst within the fluidized bed at conditions sufficient to produce a polyolefin.

A system and method for charging a chromium-based catalyst to a mix vessel; introducing a reducing agent through an entrance arrangement into the mix vessel, and agitating a mixture of the chromium-based catalyst, the reducing agent, and a solvent in the mix vessel to promote contact of the reducing agent with the chromium-based catalyst to give a reduced chromium-based catalyst.

Disclosed herein are methods of controlling polymer properties in polymerization processes that use a chromium-based catalyst. An embodiment discloses a method of producing a polyolefin comprising: contacting a reaction mixture and a reduced chromium oxide catalyst in a gas-phase reactor to produce the polyolefin, wherein the reaction mixture comprises a monomer and a co-monomer; and changing a reaction temperature in the gas-phase reactor by about 1° C. or more whereby a gas molar ratio of the co-monomer to the monomer is changed by about 2% or more and a co-monomer content of the polyolefin at substantially constant density is changed by about 2% or more. Additional methods and compositions are also provided.

Methods for olefin polymerization are described. The methods include a) forming a first polyolefin under a first set of polymerization conditions in the presence of a first catalyst composition and a first concentration of at least a first continuity additive composition, the first polyolefin composition having a target density, ρ 1 , and a target Flow Index, FI 1 ; and b) forming a second polyolefin composition under a second set of polymerization conditions in the presence of a second catalyst composition and a second concentration of a second continuity additive composition, the second polyolefin composition having a target density, ρ 2 , and a target Flow Index, FI 2 ; wherein the process is essentially free of providing a polymerization neutralizing composition between steps a) and b).

A system and method for charging a chromium-based catalyst to a mix vessel; introducing a reducing agent through an entrance arrangement into the mix vessel, and agitating a mixture of the chromium-based catalyst, the reducing agent, and a solvent in the mix vessel to promote contact of the reducing agent with the chromium-based catalyst to give a reduced chromium-based catalyst.