The invention relates to a process for the polymerization of olefins comprising the comprising the steps of a. Polymerizing olefins in a reaction mixture comprising monomers, diluent, processing as aids to prepare a product stream comprising polyolefins, monomers and diluent; b. Removing the polyolefins from the product stream to obtain a purge stream; c. Removing gaseous components from the purge stream to obtain a liquid fraction; d. Treating the liquid fraction with at least one ionic liquid to obtain a fraction containing unsaturated hydrocarbons; e. Recycling the fraction containing unsaturated hydrocarbons to the reaction mixture, optionally after purification of said fraction containing unsaturated hydrocarbons. The invention also relates to an olefin polymerization system comprising a polymerization reactor, a purge vessel, a vent gas recovery and an ionic liquid separator for separating liquid alkenes from liquid alkanes, wherein the liquid alkenes which are separated from the alkanes in the ionic liquid separator can be recycled to the polymerization reactor.

The invention relates to a process for the polymerization of olefins comprising the comprising the steps of a. Polymerizing olefins in a reaction mixture comprising monomers, diluent, processing as aids to prepare a product stream comprising polyolefins, monomers and diluent; b. Removing the polyolefins from the product stream to obtain a purge stream; c. Removing gaseous components from the purge stream to obtain a liquid fraction; d. Treating the liquid fraction with at least one ionic liquid to obtain a fraction containing unsaturated hydrocarbons; e. Recycling the fraction containing unsaturated hydrocarbons to the reaction mixture, optionally after purification of said fraction containing unsaturated hydrocarbons. The invention also relates to an olefin polymerization system comprising a polymerization reactor, a purge vessel, a vent gas recovery and an ionic liquid separator for separating liquid alkenes from liquid alkanes, wherein the liquid alkenes which are separated from the alkanes in the ionic liquid separator can be recycled to the polymerization reactor.

A process comprises polymerizing an olefin monomer in a loop reactor in the presence of a catalyst and a diluent, and producing a slurry comprising solid particulate olefin polymer and diluent. The Biot number is maintained at or below about 3.0 within the loop reactor during the polymerizing process. The slurry in the loop reactor forms a slurry film having a film coefficient along an inner surface of the reactor wall, and the film coefficient is less than about 500 BTU.Math.hr.sup.−1.Math.ft.sup.−2.Math.° F..sup.−1.

A process comprises polymerizing an olefin monomer in a loop reactor in the presence of a catalyst and a diluent, and producing a slurry comprising solid particulate olefin polymer and diluent. The Biot number is maintained at or below about 3.0 within the loop reactor during the polymerizing process. The slurry in the loop reactor forms a slurry film having a film coefficient along an inner surface of the reactor wall, and the film coefficient is less than about 500 BTU.Math.hr.sup.−1.Math.ft.sup.−2.Math.° F..sup.−1.

A process comprises polymerizing an olefin monomer in a loop reactor in the presence of a catalyst and a diluent, and producing a slurry comprising solid particulate olefin polymer and diluent. The Biot number is maintained at or below about 3.0 within the loop reactor during the polymerizing process. The slurry in the loop reactor forms a slurry film having a film coefficient along an inner surface of the reactor wall, and the film coefficient is less than about 500 BTU.Math.hr.sup.−1.Math.ft.sup.−2.Math.° F..sup.−1.

Described herein is a polymerization reactor system comprising at least one loop reactor and/or at least one transfer line, and further comprising at least one withdrawal valve, wherein the at least one withdrawal valve is mounted to a wall of a lower horizontal segment of the loop reactor and/or to a wall of the transfer line, at an angle a of more than 0° and equal to or less than 85°, determined from perpendicular to a tangent of the wall at the mounting position in flow direction of a slurry in the loop reactor and/or in the transfer line. The valve piston of the at least one withdrawal valve comprises a valve plate at an end directed to the at least one loop reactor and/or at an end directed to the at least one transfer line, the valve plate being shaped according to an inner wall of the at least one loop reactor and/or according to an inner wall of the at least one transfer line such that the valve piston is flush with the inner wall of the at least one loop reactor and/or with the inner wall of the at least one transfer line in a closed position of the withdrawal valve. By using such a withdrawal valve, a limitation of the effective withdrawal area can be avoided or at least be reduced such that the liquid slurry can efficiently be withdrawn and the risk of plugging is reduced. Further disclosed is a method for producing an olefin polymer in the inventive polymerization reactor system.

Described herein is a polymerization reactor system comprising at least one loop reactor and/or at least one transfer line, and further comprising at least one withdrawal valve, wherein the at least one withdrawal valve is mounted to a wall of a lower horizontal segment of the loop reactor and/or to a wall of the transfer line, at an angle a of more than 0° and equal to or less than 85°, determined from perpendicular to a tangent of the wall at the mounting position in flow direction of a slurry in the loop reactor and/or in the transfer line. The valve piston of the at least one withdrawal valve comprises a valve plate at an end directed to the at least one loop reactor and/or at an end directed to the at least one transfer line, the valve plate being shaped according to an inner wall of the at least one loop reactor and/or according to an inner wall of the at least one transfer line such that the valve piston is flush with the inner wall of the at least one loop reactor and/or with the inner wall of the at least one transfer line in a closed position of the withdrawal valve. By using such a withdrawal valve, a limitation of the effective withdrawal area can be avoided or at least be reduced such that the liquid slurry can efficiently be withdrawn and the risk of plugging is reduced. Further disclosed is a method for producing an olefin polymer in the inventive polymerization reactor system.

This disclosure describes polymerization processes and processes for quenching polymerization reactions using reactive particulates, such as amorphous silica, as quenching agents, typically in solution or bulk polymerization processes.

This disclosure describes polymerization processes and processes for quenching polymerization reactions using reactive particulates, such as amorphous silica, as quenching agents, typically in solution or bulk polymerization processes.

A continuous inverse emulsion polymerization process may involve combining an aqueous monomer composition with an oil composition in a premix vessel and allowing the aqueous monomer composition to interact with the oil composition in the premix vessel for a period of time effective to form a stable pre-emulsion. The stable pre-emulsion may then be homogenized to form a homogenized emulsion that is then polymerized to form a water-in-oil inverse emulsion polymer. By forming a stable pre-emulsion that is then homogenized, the resulting water-in-oil inverse emulsion polymer may have uniform and consistent polymer size distribution.