Method of catalyst transitions in olefin polymerizations
AssigneeBorealis A/S
InventorsVidar Almquist, Tone Aastad, Ingrid Sorum Melaaen, Harri Hokkanen, Kalle Kallio
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Abstract
A method for transitioning between two different catalysts in olefin polymerizations, a first catalyst and a second catalyst, comprising the steps of: discontinuing the feed of the first catalyst into the polymerization reactor, and introducing the second catalyst into the reactor, wherein the transition is performed between a chromium-based catalyst and a metallocene catalyst.
Claims9
A method of transitioning between two different catalysts in a olefin polymerization comprising the steps of:
- a) feeding a chromium-based catalyst into an olefin polymerization reactor;
- b) discontinuing said feed of said chromium-based catalyst into said polymerization reactor;
- c) introducing a deactivating agent selected from the group consisting of alcohols, water and oxygen into said polymerization reactor to stop said olefin polymerization reaction or, optionally, kill said chromium-based catalyst;
- and
- d) introducing a metallocene catalyst into said reactor.
A method of transitioning between two different catalysts in an olefin polymerization comprising the steps of:
- a) feeding a first chromium catalyst into an olefin polymerization reactor;
- b) discontinuing said chromium catalyst feed into said polymerization reactor;
- and
- c) feeding a metallocene catalyst into said continuous reactor, with the proviso that no deactivating agent is introduced into the reactor.
Dependencies are inferred from the claim text.