Basell Polyolefine Gmbh

Basf Aktiengesellschaft

Paulus De Lange

Dieter Lilge

Shahram Mihan

Andreas Deckers

Rainer Karer

Martin Schneider

Kaspar Evertz

Manfred Hecker

Markus Enders

Ursula Rief

Johannes Hack

Udo Handrich

Gunter Ludwig

Ralph Rudolph

Guido Funk

Peter K&ouml;lle

G&uuml;nther Schweier

Wolfgang Rohde

Martin Lux

Günther Schweier

Hans-Jacob Feindt

Klaus Berhalter

Cyrus Ahmadzade-Youssefi

Eberhard Herrmann

Jörg Halpap

Peter Bauer

Thomas Kessler

Harald Schmitz

Philipp Rosendorfer

Jennifer Kipke

Wolfgang Micklitz

Jörg Auffermann

Thomas Letzelter

Axel Hamann

Michael Olmscheid

Hendrik Schönfelder

Joachim Werther

Michael Witt

Thomas Perner

Axel Sperber

Hans Werner Siebenhandl

Stefan Wietfeldt-Haltenhoff

Thomas Brauch

Michael K&auml;mmerer

Werner Ritter

Holger Strecker

Bernd Brunner

Volker Billert

Thomas Bl&uuml;mel

Michael Kämmerer

Method for activation of chromium containing catalyst precursor for polymerization and improved polymerization catalyst resulting The instant invention relates to an activation of a polymerization catalyst precursor by heat treatment comprising a support material and a catalyst precursor deposited thereon in a fluidized bed activator and to the use of the activated polymerization catalyst in the manufacture of polyolefins. The Method is performed in a cylindrical activator () arranged vertically comprising tubular activator walls, a fluidization gas inlet () near the bottom, a fluidization gas outlet () near the top and a heat exchange jacket () outside the tubular activator walls, wherein the heating jacket covers the complete outer surface of the walls of the activator. The catalyst prepared by that method is improved with respect to its minor content of impurities and causes less interruptions during gas-phase polymerization or slurry polymerization either in stirred vessel or loop.

Method for activation of chromium containing catalyst precursor for polymerization and the resulting polymerization catalyst

The instant invention relates to an activation of a polymerization catalyst precursor by heat treatment comprising a support material and a catalyst precursor deposited thereon in a fluidized bed activator and to the use of the activated polymerization catalyst in the manufacture of polyolefins. The activation involves heat treatment in the presence of oxygen. After that activation the oxygen in the activator is replaced by inert gas via flushing until the fluidization gas emerging from the activator comprises oxygen in a maximum amount of up to 5 ppm. The catalyst prepared by that method is improved with respect to prevent reactor fouling during gas-phase polymerization or slurry polymerization either in stirred vessel or loop.

A polyethylene composition, in particular suitable for the preparation of films, and a process for preparing the same are described. The polyethylene composition of the invention comprises from 50 to 89% by weight of a first polyethylene component comprising at least one multimodal polyethylene including a plurality of ethylene polymer fractions having distinct molecular weights and comonomer contents, at least one of said plurality of ethylene polymer fractions being prepared by the use of a single site catalyst, and from 50 to 11% by weight of a second polyethylene component comprising a low or medium density polyethylene.

Polyethylene composition suitable for the preparation of films and process for preparing the same

An apparatus for the polymerization of olefins, in particular ethylene, comprising a gas-phase fluidized-bed reactor (), a recycle gas line () connected to the reactor for discharging and recirculating the recycle gas stream comprising the unpolymerized olefin and a cyclone () located in the recycle gas line for the reduction and precipitation of the solid particles entrained in the recycle gas from the reactor, with the cyclone comprising an upper section () which has an essentially vertical central axis, whose wall extends along a rotationally symmetric body and which is provided with a cyclone inlet () arranged eccentrically relative to the central axis, a middle section () which adjoins the upper section () and whose wall extends along a rotationally symmetric body which tapers in a downward direction, a lower section () for discharging the solid particles precipitated from the recycle gas which adjoins the middle section () and whose wall extends along a rotationally symmetric body and a tube () extending essentially axially symmetrically down into the upper section and, if appropriate, the middle section for discharging the recycle gas which has been freed of the particles. According to the invention the ratio Hof the distance hfrom the lower end of the tube () extending downward into the cyclone to the intersection () of an imaginary extension of the wall of the downward-extending tube () with the wall of the middle section () to the diameter dof the downward-extending tube () is from 3 to 8, in particular from 4 to 7.

Apparatus for the gas-phase polymerization of olefins, in particular ethylene

Apparatus for the polymerization of olefins, in particular ethylene, comprising a gas-phase fluidized-bed reactor (), a product offtake line () for taking polymer particles either continuously or discontinuously from the reactor (), which line () is connected to a depressurization vessel () for separating polymer particles and gas, a recycle gas filter () for freeing the gas of entrained fine particles connected to the depressurization vessel (), a compressor which compresses the gas which has been freed of fine particles and recirculates it into the reactor (), with the recycle gas filter () having an inlet chamber () provided with a gas inlet (), an outlet chamber () provided with a gas outlet (), an essentially vertical sheet-like filter medium () for retaining the fine particles which separates the inlet chamber () from the outlet chamber () and a particle outlet (). The inlet chamber () has a dividing wall () which is arranged essentially parallel to the filter medium () and separates the inlet chamber () into an inflow region (), which is connected to the gas inlet (), and a filter region () in which the filter medium is located and has an upper opening and a lower opening which are dimensioned so that from 60 to 90% of the volume flow flows through the upper opening so that flow along the filter medium () from the top downward results.

Apparatus and process for the gas-phase polymerization of olefins

A method for the treatment of catalysts or catalyst carriers by: a) introducing and distributing a gas in the lower section of a reactor containing a catalyst or catalyst carrier bulk material; b) forming a fluidized bed in the reactor; c) treating the particles in the fluidized bed while removing the fine particles an/or retaining the course particles by means of a separating organ and d) discharging the reactor. To this end, a reactor bottom which tapers downwards is used.

Fluidized bed method and reactor for the treatment of catalysts and catalyst carriers

Substituted monocyclopentadienyl, monoindenyl, monofluorenyl or heterocyclopentadienyl complexes of chromium, molybdenum or tungsten, wherein at least one of the substituents of the cyclopentadienyl ring carries a rigid donor function which is not exclusively bonded through sp-hybridized carbon or silicon atoms, and a process for polymerizing olefins.

Monocyclopentadienyl complexes of chromium, molybdenum or tungsten with a donor bridge

Substituted monocyclopentadienyl, monoindenyl, monofluorenyl and heterocyclopentadienyl complexes of chromium, molybdenum or tungsten in which at least one of the substituents on the cyclopentadienyl ring carries a donor function which is bonded rigidly, not exclusively via sp-hybridized carbon or silicon atoms, and a process for the polymerization of olefins.

Monocyclopentadienyl complexes of chromium, molybdenum or tungsten

Substituted monocyclopentadienyl, monoindenyl, monofluorenyl and heterocyclopentadienyl complexes of chromium, molybdenum or tungsten in which at least one of the substituents on the cyclopentadienyl ring carries a donor function which is bonded rigidly, not exclusively via sp -hybridized carbon or silicon atoms, and a process for the polymerization of olefins.

In a process for producing Phillips catalysts in which an oxidic support material is treated in suspension with a chromium salt solution and subsequently, after removing the solvent, calcined in an oxygen-containing atmosphere at above 300&deg; C., the oxidic support material and/or the catalyst after calcination are/is, according to the present invention, comminuted until a mean particle size of <100 &mgr;m has been reached and the proportion of particles having a size of <50 &mgr;m is at least 30%, preferably in the range from 40 to 80%. A process for preparing homopolymers or copolymers of ethene in a loop reactor at from 30 to 150&deg; C. under a pressure in the range from 0.2 to 15 MPa in the presence of a catalyst produced by the process of the present invention is also provided.

Method for producing Phillips catalysts for polymerizing olefins with better productivity rates in the particle-form process

Method for the discontinuous thermal treatment of catalyst material

Optimized method for the production of catalyst supports based on silica gel and chromium catalysts supported on silica gel

The invention relates to a method for producing supported chromium catalysts for the polymerisation of olefins by loading a xerogel support with chromium by adding to the xerogel support a volume of a 0.025 to 15% by weight solution of a chromium compound or a volume of a solution comprising from 0.025 to 7.8% by weight of Cr which is essentially converted into a chromium(VI) compound on heating in a water-free stream of gas under oxidizing conditions at temperatures in the range from 300 to 1100&deg; C. for a period of from 10 to 1000 minutes in a solvent which comprises a maximum of 20% by weight of water, and subsequently evaporating the solvent, where the volume of the chromium salt solution employed is smaller than the pore volume of the xerogel support.

Method for producing supported chrome catalysts and the use thereof for the polymerization of olefins

The invention relates to a method for the production of copolymer based on ethylene by continuous copolymerization of ethylene and comonomer in a reactor in the presence of a catalyst. In this method, in a first step of the copolymerization, a mixture comprising ethylene and comonomer of such a composition that a copolymer-containing coating deposits in the reactor is metered into the reactor and/or generated in the reactor, and, in a second step, the concentration of the comonomer in the metered-in mixture and/or in the mixture generated in the reactor is reduced sufficiently and/or the concentration of the ethylene in the metered-in mixture and/or in the mixture generated in the reactor is increased sufficiently that the coating is removed from the reactor either partially or completely. The method has the advantage that the production of copolymer does not have to be interrupted during cleaning of the reactor.

Method for producing an ethylene copolymer

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Wesseling, Germany

Paulus De Lange