Described herein is a process and an apparatus for preparing propylene homopolymers and copolymers, which comprises polymerizing propylene optionally with comonomers in the presence of a catalyst at elevated temperature and pressure in at least one slurry reactor and at least one gas phase reactor, the polymerization product of at least one slurry reactor, containing unreacted monomers, being conducted to a first gas phase reactor essentially without recycling of the unreacted monomers to the slurry reactor. The invention provides for fast start-ups because the gas phase bed material is available directly from the loop reactor.

Process and apparatus for preparing propylene homopolymers and copolymers

A process for producing polyethylene compositions in the presence of catalytic system of ethylene polymerizing catalyst and cocatalyst in a multistage reaction sequence consisting of successive liquid phase and gas phase polymerizations. The process comprises at least one continuous reaction sequence, in which in the first step ethylene and optionally hydrogen and comonomer are polymerized in a loop reactor in a low boiling hydrocarbon medium in the presence of ethylene polymerizing catalyst and cocatalyst, the residence time and reaction temperature being such that the proportion of the ethylene polymer produced in the reactor from the end product of the process is between 1-20 wt.%, the reaction mixture removed from the step is transferred to second step where polymerization is continued in a loop reactor by adding ethylene, hydrogen and optionally inert hydrocarbon, comonomers and cocatalysts, the residence time being at least 10 minutes, the reaction mixture is removed from the loop reactor, at least an essential part of the reaction medium is removed and the polymer transferred to a third step where polymerizing is carried out in a gas phase reactor in the presence of added ethylene and optionally hydrogen, comonomers and cocatalysts.

Process for preparing polyethylene

The present invention concerns a process and an apparatus for continuous polymerisation of olefin monomers. In particular, the present invention concerns a process and an apparatus for continuous polymerisation olefin monomers like ethylene and other monomers, wherein an olefin monomer is polymerised in slurry phase in an inert hydrocarbon diluent in at least one loop reactor. According to the invention, a polymer slurry is continuously withdrawn from the loop reactor and concentrated. The concentrated slurry is conducted to a flash unit in order to remove the remaining fluid phase, and gas obtained is compressed in a flash gas compressor before it is being fed to a distillation section. By means of the present invention it is possible reduce the size of the flash gas compressor and the capacity of the distillation sections. This significantly reduces investment cost for a continuously operated polymerization apparatus.

Process and apparatus for producing olefin polymers

There is provided a process for the copolymerisation of propylene with at least one C4-20 α-olefin or C4-20 diene in a reaction medium in the presence of a catalyst system at a temperature of greater that 80 °C or at a temperature and pressure above the critical temperature and pressure of the reaction medium. Under such conditions, comonomer incorporation is higher than under standard conditions.

Process for preparing propylene copolymers

Described herein is a process and an apparatus for polymerizing propylene. The process comprises carrying out the polymerization in at least one slurry reactor and at least one gas phase reactor without recycling unreacted monomers to the slurry reactor. A polymerization product containing unreacted monomers is recovered from the slurry reactor and volatile components are separated from the product in a separation unit. The polymerization product is recovered from the separation unit and conducted to a first gas phase reactor; and at least a part of the volatile components are recovered from the separation unit and conducted them to a gas phase reactor. At least 10 % of the polymer product is produced in the gas phase reactor(s). The invention provides propylene homopolymers and alloys of propylene homopolymers and copolymers having good impact and creep properties.

Process for preparing polypropylene alloys

The present invention relates to a multistage, continuous process for the preparation of propylene-ethylene impact copolymers comprising the use of a recirculating pipe-loop reactor for homopolymerizing propylene, a cyclone separator for removing fines, a gas-phase fluidized bed reactor for additional propylene homopolymerization, and a gas-phase fluidized bed reactor for propylene/ethylene copolymerization.

Multistage copolymerization process

Partial oxidation of organic compounds

Ethylene oxide is separated from admixed inert gaseous components and recovered as a gaseous fraction by (a) contacting the gaseous mixture with a lean aqueous absorbant to produce an ethylene oxide-rich absorbate; (b) flashing the ethylene oxide-rich absorbate at a temperature below about 65 DEG C to produce a condensate lean in inerts; and (c) contacting, in an ethylene oxide stripping zone, the inerts-lean condensate with a stripping vapor at or slightly above atmospheric pressure to produce a gaseous overhead rich in ethylene oxide.

Recovery of ethylene oxide from admixed inert gaseous components

Apparatus for carrying out partial oxidation of organic compounds

IN THE DIRECTION OF MOVEMENT OF THE BED. THE STREAMS AND CONTACT BED ARE FLOWED CO-CURRENTLY THROUGH THE REACTION ZONE AND THE REACTED MIXTURED IS SEPARATED FROM THE BED AFTER PASSAGE THROUGH AT LEAST A PART OF THE LENGTH OF ONE OF THE PATHS. A PROCESS FOR CARRYING OUT PARTIAL OXIDATION OF ORGANIC COMPOUNDS IN THE VAPOR PHASE BY CIRCULATING CATALYTIC GRANULAR SOLIDS CONTINUOUSLY THROUGH A SYSTEM WHICH INCLUDES VERTICALLY ELONGATED UP-CLOW AND DOWN-FLOW PATHS, ONE OF WHICH PASSES THROUGH AN ELONGATED REACTION ZONE. THE SOLIDS MOVE AS A COMPACT BED, AT LEAST THROUGH THE REACTION ZONE, AND SEPARATE GASEOUS STREAMS CONTAINING RESPECTIVELY AN ORGANIC COMPOUND TO BE OXIDIZED AND OXYGEN ARE CONTINUOUSLY ADMITTED DIRECTLY INTO THE MOVING CONTACT BED WITHIN THE REACTION ZONE AT POINTS SPACED APART

E Gordon Foster

Papers

Multistage copolymerization process

Partial oxidation of organic compounds

Recovery of ethylene oxide from admixed inert gaseous components

Apparatus for carrying out partial oxidation of organic compounds

Process for carrying out partial oxidation of organic compounds