Abstract: A process is provided that produces polyolefins.

Abstract: Polymer solids are maintained in an intermediate pressure zone for a desired polymer solids residence time and then transferred to a purge zone or other lower pressure zone. An increase in the polymer solids residence time in the intermediate pressure zone allows more diluent to flash or separate, thereby avoiding or reducing the need for a low pressure flash zone. A fluff chamber may be disposed between the intermediate pressure zone and a lower pressure zone transporter tank may be used to transport polymer solids after the intermediate pressure zone.

Abstract: A polymerization loop reactor including a loop reaction zone, a continuous takeoff, and a fluid slurry disposed in the reaction zone. A generally cylindrical wall defines the loop reaction zone. The length of the loop reaction zone and the nominal outside diameter of the generally cylindrical wall define a length/diameter ratio greater than 250. The reactor can be charged with a fluid slurry including an olefin monomer reactant, solid olefin polymer particles, and a liquid diluent. The concentration of the solid olefin polymer particles in the slurry can be greater than 40 weight percent based on the weight of polymer particles and the weight of liquid diluent. Also disclosed is a polymerization process carried out by polymerizing, in the loop reaction zone of a reactor as defined above, at least one olefin monomer in a liquid diluent to produce a fluid slurry as defined above.

Abstract: An olefin polymerization apparatus is disclosed wherein monomer, diluent and catalyst are circulated in a continuous pipe loop reactor and an intermediate product slurry is recovered by a continuous product take off means. The intermediate product slurry is passed to a hydrocyclone to stratify polymer particles based on size. A slurry containing predominantly fines is withdrawn overhead and returned to the reaction zone. The slurry containing predominantly fines is preferably returned to the polymerization zone just upstream of the circulation pump and in a preferred embodiment this pressure differential is the sole driving force for the hydrocyclone separation. In another embodiment the product slurry from the bottom of the hydrocyclone is passed to a solids-liquid separator where the solids settle to the bottom and essentially polymer free diluent is recycled. In another embodiment, the intermediate product slurry is withdrawn via a conical settling leg.

Abstract: A process and apparatus for passing a polymerization effluent, comprising solid polymer, unreacted monomer, diluent and minor amounts of contaminants, to a high pressure flash where most of the fluid components are flashed and wherein a slip stream comprising diluent and minor amounts of monomer is separated from the bulk of the flashed fluid components. The slip stream is subjected to olefin removal to give an essentially olefin-free stream for recycle to a catalyst mud preparation area. The bulk of the flashed fluid components are recycled directly back to the polymerization zone without expensive olefin removal, although treatment to remove other contaminants can optionally be performed. The polymer and entrained fluid is passed to a low pressure flash zone where the fluids are flashed off, compressed and joined with the flash from the high pressure flash tank.

Abstract: A process and apparatus for passing a polymerization effluent, comprising solid polymer, unreacted monomer, diluent and minor amounts of contaminants, to a high pressure flash where most of the fluid components are flashed and wherein a slip stream comprising diluent and minor amounts of monomer is separated from the bulk of the flashed fluid components. The slip stream is subjected to olefin removal to give an essentially olefin-free stream for recycle to a catalyst mud preparation area. The bulk of the flashed fluid components are recycled directly back to the polymerization zone without expensive olefin removal, although treatment to remove other contaminants can optionally be performed. The polymer and entrained fluid is passed to a low pressure flash zone where the fluids are flashed off, compressed and joined with the flash from the high pressure flash tank.

Abstract: An olefin polymerization apparatus is disclosed wherein monomer, diluent and catalyst are circulated in a continuous pipe loop reactor and an intermediate product slurry is recovered by a continuous product take off means. The intermediate product slurry is passed to a hydrocyclone to stratify polymer particles based on size. A slurry containing predominantly fines is withdrawn overhead and returned to the reaction zone. The slurry containing predominantly fines is preferably returned to the polymerization zone just upstream of the circulation pump and in a preferred embodiment this pressure differential is the sole driving force for the hydrocyclone separation. In another embodiment the product slurry from the bottom of the hydrocyclone is passed to a solids-liquid separator where the solids settle to the bottom and essentially polymer free diluent is recycled. In another embodiment, the intermediate product slurry is withdrawn via a conical settling leg.

Abstract: A process and apparatus for passing a polymerization effluent, comprising solid polymer, unreacted monomer, diluent and minor amounts of contaminants, to a high pressure flash where most of the fluid components are flashed and wherein a slip stream comprising diluent and minor amounts of monomer is separated from the bulk of the flashed fluid components. The slip stream is subjected to olefin removal to give an essentially olefin-free stream for recycle to a catalyst mud preparation area. The bulk of the flashed fluid components are recycled directly back to the polymerization zone without expensive olefin removal, although treatment to remove other contaminants can optionally be performed. The polymer and entrained fluid is passed to a low pressure flash zone where the fluids are flashed off, compressed and joined with the flash from the high pressure flash tank.

Abstract: In accordance with the present invention there is provided a new solid aluminoxy composition prepared by reacting aluminoxane with a boroxine. Still further there is provided olefin polymerization catalyst systems incorporating the inventive solid aluminoxy composition. Still further, there is provided processes of polymerization using the inventive solid aluminoxy composition.

Abstract: A process is provided to produce polyolefins having a multimodal molecular weight distribution at the molecular level by contacting at least one mono-1-olefin in a polymerization zone, under polymerization conditions, with two different types of supported chromium catalyst systems. The first catalyst system comprises a chromium oxide catalyst system which comprises chromium oxide supported on an inorganic oxide. The second catalyst system comprises a chromocene catalyst system which comprises chromocene supported on an inorganic oxide. The resultant, recovered polymer has a multimodal, or at least a bimodal, molecular weight distribution.

Abstract: A process is provided to produce polyolefins having a multimodal molecular weight distribution at the molecular level by contacting at least one mono-1-olefin in a polymerization zone, under polymerization conditions, with two different types of supported chromium catalyst systems. The first catalyst system comprises a chromium oxide catalyst system which comprises chromium oxide supported on an inorganic oxide. The second catalyst system comprises a chromocene catalyst system which comprises chromocene supported on an inorganic oxide. The resultant, recovered polymer has a multimodal, or at least a bimodal, molecular weight distribution.

Abstract: In accordance with the present invention there is provided a new solid aluminoxy composition prepared by reacting aluminoxane with a boroxine. Still further there is provided olefin polymerization catalyst systems incorporating the inventive solid aluminoxy composition. Still further, there is provided processes of polymerization using the inventive solid aluminoxy composition.