Abstract: Described herein are methods comprising contacting one or more olefins with a catalyst system in a polymerization reactor at conditions sufficient to produce a polyolefin, wherein the catalyst system comprises a first metallocene catalyst compound comprising a first transition metal atom, two cyclopentadienyl ligands bound to the first transition metal atom, and two leaving groups bound to the first transition metal atom, wherein at least one leaving group is selected from the group consisting of a halo-phenoxy and a halo-alkoxy; wherein the first metallocene catalyst compound has a catalyst productivity that is at least 20% greater than a comparative metallocene catalyst compound used to produce the same polyolefin, wherein the comparative metallocene catalyst compound is the same as the first metallocene catalyst compound except neither leaving group is a halo-phenoxy or a halo-alkoxy.

Abstract: Provided are systems and methods for separating a purge gas recovered from a polyethylene product. The method includes recovering a polyethylene product containing one or more volatile hydrocarbons from a polymerization reactor and contacting the polyethylene product with a purge gas to remove at least a portion of the volatile hydrocarbons to produce a polymer product having a reduced concentration of volatile hydrocarbons and a purge gas product enriched in volatile hydrocarbons. The purge gas product is compressed to a pressure of 2,500 kPaa to 10,000 kPaa, and is then cooled and separated into at least a first product, a second product, and a third product. A portion of one or more of the first, second, or third products is then recycled as a purge gas, to the polymerization reactor, or to the purge gas product enriched in volatile hydrocarbons prior to compression, respectively.

Abstract: Disclosed herein are improvements in recycle gas cooler systems in gas-phase polymerization processes that reduce the tendency for cooler fouling, including a recycle gas cooler system comprising a shell-and-tube heat exchanger. One or more of the tubes of the shell-and-tube heat exchanger may have a flared tube inlet at the tube sheet. The shell-and-tube heat exchanger may also be coupled to a straight inlet pipe having a length that is either at least about 5 times the inner diameter of the straight inlet pipe or at least about 15 feet, whichever is greater.

Abstract: A catalyst system for polymerizing olefin-based polymers and interpolymers is disclosed. The catalyst system may include a supported chromium catalyst and a Ziegler-Natta catalyst comprising a bulking agent, Mg, and Ti. The Ziegler-Natta catalysts in catalyst systems disclosed herein run exceptionally well without addition of excessive amounts of co-catalyst, thus allowing for use of chromium based supported catalysts that would otherwise be overwhelmed by aluminum alkyl. Further, embodiments disclosed herein may be run without an internal electron donor, and the lack of an internal electron donor in the system also prevents poisoning of the chromium catalysts by the internal electron donor. By including or co-feeding a chromium based catalyst with these Ziegler-Natta catalysts, it has been found that the molecular architecture of the resulting polyolefins, such as polyethylenes, may provide for resins with excellent processing properties.

Abstract: Methods for the removal of impurities, for example, carbon monoxide, from a polymerization feed streams are provided.

Abstract: Improved systems and processes for storing resins are disclosed herein. These systems and processes are especially useful for reducing the tendency of resins to sinter. In polymerization processes, the improvements disclosed herein can reduce the tendency of resins to sinter while also allowing downstream operations to continue.

Abstract: Methods and systems for controlling a polymerization reaction in a non-sticking regime are disclosed. An exemplary method includes measuring parameters for the polymerization reaction including a reactor temperature and a concentration of an induced condensing agent (ICA) in a polymerization reactor. An equivalent partial pressure ((PICA)equiv) of the ICA is calculated. The polymerization reaction is located in a two dimension space defined by a reactor temperature dimension and a ((PICA)equiv) dimension. The location in the two dimensional space is compared to an non-sticking regime, defined as the space between an upper temperature limit (UTL) curve and a lower temperature limit (LTL) curve. The parameters of the polymerization reaction are adjusted to keep the polymerization reaction within the non-sticking regime.

Abstract: Methods and systems for controlling a polymerization reactor in a non-sticking regime are disclosed. An exemplary method includes measuring parameters for the polymerization reaction including a reactor temperature and a concentration of an induced condensing agent (ICA) in a polymerization reactor. An equivalent partial pressure ((PICA)equiv) of the ICA is calculated. The polymerization reactor operation is located in a two dimension space defined by a reactor temperature dimension and a ((PICA)equiv) dimension. The location in the two dimensional space is compared to an non-sticking regime, defined as the space between an upper temperature limit (UTL) curve and a lower temperature limit (LTL) curve. Parameters of the polymerization reactor are adjusted to keep the reactor within the non-sticking regime.

Abstract: 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.

Abstract: Disclosed herein are methods of preparing a catalyst system comprising a spray-dried activator and polymerization processes employing these catalyst systems.

Abstract: A polymerization process is disclosed, including: providing a reactor component suspended in a hydrocarbon gel; introducing the reactor component to a polymerization reactor; and polymerizing an olefin in the polymerization reactor to form an olefin-based polymer. Another polymerization process is disclosed, including: providing a hydrocarbon gel comprising a reactor component suspended therein; combining the hydrogen gel with an additional reactor feed; introducing the combined mixture of the hydrocarbon gel and the additional reactor feed to a polymerization reactor; and polymerizing an olefin in the polymerization reactor to form an olefin-based polymer. A hydrocarbon gel is disclosed, including: a liquid hydrocarbon; a gelling agent; and a reactor component.

Abstract: A discharge system for removing a solid/gas mixture from a fluidized bed pressure vessel is provided. The system includes a fluidized bed pressure vessel, settling vessels, discharge lines, primary discharge valves, vent lines, primary vent valves, crosstie lines, crosstie valves, and primary exit valves wherein the system is absent a transfer tank, and absent a filter element. The method provides for transferring a solid/gas mixture via a discharge line from the pressure vessel to a settling vessel, wherein gas is separated from the mixture, and the gas is transferred to at least one other settling vessel via a crosstie line. After the solids are transferred out of the settling vessel, the empty vessel then receives gas from other settling vessels in the system.

Abstract: Apparatus and methods for separating volatiles from particulates are provided. The apparatus includes a separator having an internal volume and a fluid discharge outlet, a particulate discharge outlet, a particulate inlet, and a fluid inlet disposed on the separator and in fluid communication with the internal volume. The particulate inlet is disposed toward a first end of the separator and the fluid inlet is disposed toward a second end of the separator. The fluid inlet includes one or more openings disposed through a sidewall of the separator.

Abstract: Spray-dried catalyst compositions comprising a transition metal complex and polymerization processes employing the same are disclosed herein. An embodiment provides a spray-dried catalyst composition comprising a transition metal catalyst component represented by the following formula: (I) and polymerization process employing the same.

Abstract: A process for the production of ethylene alpha-olefin copolymers is disclosed. The process may include feeding a catalyst system comprising a supported metallocene, such as a hafnocene, having pores saturated with a selected liquid agent, to a gas phase polymerization reactor. Ethylene and an alpha-olefin may then be contacted with the supported metallocene in the gas phase polymerization reactor to produce an ethylene alpha-olefin copolymer. The copolymer may have a density of less than 0.93 g/cm3, a melt index (I2) of less than 2 dg/min, and a melt flow ratio (I21/I2) of at least 28. To advantageously result in desired effects on catalyst properties and/or polymer properties, the liquid agent may be selected to advantageously manipulate catalyst temperature profiles and/or catalyst-monomer interaction during an initial heating period when the catalyst is first introduced to the reactor.

Abstract: A method for the delivery of a catalyst to a polymerization reactor is disclosed, comprising: contacting a catalyst with a carrier fluid comprising an inert hydrocarbon in gaseous form, the inert hydrocarbon having a normal boiling point of about ?1° C. to about 81° C.; and flowing the carrier fluid to the polymerization reactor such that the carrier fluid transports the catalyst to the polymerization reactor. A catalyst delivery system is disclosed, comprising: a catalyst vessel for containing a catalyst; a catalyst injection line for delivering the catalyst to a polymerization reactor, the catalyst injection line being in fluid communication with the catalyst vessel and the polymerization reactor; and a carrier fluid line in fluid communication with the catalyst injection line for delivering a carrier fluid comprising an inert hydrocarbon to the catalyst injection line, the inert hydrocarbon having a normal boiling point of about ?1° C. to about 81° C.

Abstract: Various methods and systems for using oxygen in a polyolefin polymerization reactor system are provided. In certain embodiments, the methods are performed in conjunction with a polymerization reactor system such as a gas-phase reactor system.

Abstract: A method of synthesizing an alkyl cyclopentadiene compound is disclosed. The method includes contacting at least one cyclopentadienyl anion source and at least one alkyl group source to form at least one alkyl cyclopentadiene compound. The method further includes extracting the alkyl cyclopentadiene compound with a hydrocarbon solvent. The alkyl cyclopentadiene compound may be converted to a metallocene catalyst compound.

Abstract: The invention relates to catalyst compositions including at least one catalyst compound and at least one continuity additive such as poly-oxo-metal carboxylate compound and their use in the polymerization of olefins.

Abstract: A polymerization process includes contacting the following in a gas-phase reactor system under polymerization conditions for making a polymer product: a metallocene-based catalyst system including a supported constrained geometry catalyst, at least one monomer, and an additive selected from a group consisting of an aluminum distearate, an ethoxylated amine, and a mixture thereof. The additive may be selected from a group consisting of an aluminum distearate, an ethoxylated amine, polyethylenimines, and other additives suitable for use in the production of polymers for food contact applications and end products, including a mixture of a polysulfone copolymer, a polymeric polyamine, and oil-soluble sulfonic acid, in a carrier fluid, and mixtures thereof.