Patent EP0471497A1 successfully refreshed from Google Patents.
EP0471497A1
Expired / Lapsed
EP
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Gas phase polymerisation
Assignee: BP Chemicals SNC
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Filing: 1991-08-06
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Granted: —
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Expires: 2011-08-06
Abstract
Abstract The present invention relates to a process for stopping an olefin polymerisation which is carried out in a low pressure gas phase reactor, which process comprises introducing an effective quantity of deactivating agent into the reactor, characterised in that the olefin polymerisation is carried out using a chromium oxide catalyst and in that the deactivating agent is selected from oxygen, ammonia, water and carbon monoxide and is introduced over a relatively short period of time. The deactivating agent is preferably introduced into the polymerisation reactor in a quantity such that in the reactor the weight ratio of the deactivating agent to the catalyst is at least 0,001.
Inventors
- 👤 Laszlo Bp Chemicals S.N.C. Havas
- 👤 John Gabriel Bp Chemicals S.N.C. Speakman
- 👤 Claudine Centre De Recherches Lalanne-Magne
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 18:03
CPC Classifications
C; C08; C08F; C08F10/00; C08F2/00; C08F10/02; C08F110/00; C08F110/02; C08F210/00; C08F210/16
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
70 words
A process for stopping an olefin polymerisation which is carried out in a low pressure gas phase reactor, which process comprises introducing an effective quantity of deactiving agent into the reactor characterised in that the olefin polymerisation is carried out using a chromium oxide catalyst and in that the deactivating agent is selected from oxygen, ammonia, water and carbon monoxide and is introduced over a relatively short period of time.
Claim 2
Dependent Claim
31 words
A process according to Claim 1, characterised in that the quantity of the deactivating agent introduced is from 1 to 10 times the minimum quantity necessary for stopping the olefin polymerisation.
Claim 3
Dependent Claim
34 words
A process according to Claim 2, characterised in that the quantity of the deactivating agent introduced is in the range from 2 to 3 times the minimum quantity necessary for stopping the olefin polymerisation.
Claim 4
Dependent Claim
32 words
A process according to Claim 1, characterised in that the deactivating agent is oxygen and is introduced in a quantity in the range from 2 to 80 g per kilogram of catalyst.
Claim 5
Dependent Claim
32 words
A process according to Claim 1, characterised in that the deactivating agent is water and is introduced in a quantity in the range from 10 to 80 g per kilogram of catalyst.
Claim 6
Dependent Claim
33 words
A process according to Claim 1, characterised in that the deactivating agent is carbon monoxide and is introduced in a quantity in the range from 3 to 130 g per kilogram of catalyst.
Claim 7
Dependent Claim
22 words
A process according to anyone of claims 1 to 6, characterised in that the feeding of catalyst into the reactor is discontinued.
Claim 8
Dependent Claim
22 words
A process according to anyone of claims 1 to 7, characterised in that the feeding of olefin into the reactor is discontinued.
Claim 9
Dependent Claim
24 words
A process according to anyone of claims 1 to 8, characterised in that the introduction of an organometallic compound into the reactor is stopped.
Claim 10
Dependent Claim
31 words
A process according to anyone of claims 1 to 9, characterised in that the introduction of the deactivating agent into the reactor is performed over a period shorter than 5 minutes.
Claim 11
Dependent Claim
20 words
A process according to anyone of claims 1 to 10, characterised in that the reactor is a fluidised bed reactor.
Claim 12
Dependent Claim
18 words
A process according to Claim 11, characterised in that the catalyst is in the form of a prepolymer.
References Cited (Backward Citations)
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