Chevron Phillips Chemical Company LP

Phillips Petroleum Company

Other

Ted H Cymbaluk

Max P McDaniel

Gerhard P Nowack

Marvin M Johnson

Qing R Yang

Alan L Solenberger

Eric D Schwerdtfeger

Albert P Masino

Elizabeth Ann Benham

Kathy S Clear

Jeremy M Praetorius

Errun Ding

Gary L Glass

Ashish M Sukhadia

Tony R Crain

Rex E Murray

Rajendra K Krishnaswamy

William B Beaulieu

Kumudini Jayaratne

Gary A Delzer

Michael D Jensen

Joel L Martin

Simon G Kukes

John D Hottovy

Kathy S Collins

Brent J Bertus

Matthew G Thorn

Dennis L Holtermann

Donald C Tabler

Joseph B Cross

William Chadwick Ellis

Gregory G Hendrickson

Dennis R Kidd

Tin-Tack Peter Cheung

Ronald E Brown

Jim D Byers

Steven J Secora

Patricia A Tooley

Connor D Boxell

Steve J Secora

H Kenneth Staffin

Anand Ramanathan

John D Stewart

Charles R Nease

Thomas R Parr

Charles K Newsome

Deloris R Gagan

Zhihui Gu

Daniel M Coombs

David W Dockter

Mark E Kertok

Taryn L Huber

Julian Abrego

Lawrence Szmutko

Chia-Min Fu

George R Rajaendran

Chih-An Hwang

Elliott W Johnson

Ravindranath Koyyalagunta

Marlon L Jordan

George Neil

William L Valerioti

Richard A Hernandez

Susannah Lane

Max P Mcdaniel

Conner D Boxell

Qing Yang

Kumudini C Jayaratne

Lawrence Szmuto

Elizabeth A Benham

Processes for producing activated chromium catalysts such as titanated chromium/silica catalysts are disclosed, and these processes utilize a multistep process involving exposure to inert and oxidizing atmospheres at specific temperature conditions. The resulting activated chromium catalysts have unexpectedly high melt index potential and can produce ethylene-based polymers with lower gel counts in addition to higher melt indices.

Methods of chromium catalyst activation to reduce gels and improve melt index potential

Processes for producing activated chromium catalysts such as chromium/silica catalysts and titanated chromium/silica catalysts are disclosed, and these processes utilize a multistep process involving exposure to inert and oxidizing atmospheres at specific temperature conditions. The resulting activated chromium catalysts have unexpectedly high melt index potential and can produce ethylene-based polymers with lower gel counts in addition to higher melt indices. Related activation systems are provided in which the fluidizing gas entering the fluidized bed vessel can be adjusted between an inert gas, an oxygen-containing gas, or a mixture of the inert gas and the oxygen-containing gas to minimize or prevent exotherms.

Systems and methods for chromium catalyst activation

Processes for activating chromium polymerization catalysts, which can use lower maximum activation temperatures and shorter activation times than conventional activation methods, and provide polyethylenes with high melt indices, broader molecular weight distributions, and lower long chain branching content. The activation process can comprise heating a supported chromium catalyst in an inert atmosphere to a first temperature (T) for a first hold time (t), followed by allowing the chromium catalyst to attain a second temperature (T) in the inert atmosphere, then contacting the chromium catalyst with an oxidative atmosphere for a second hold time (t), in which Tcan be less than or equal to T. Additional activation treatments and conditioning steps are disclosed which can be used to enhance the melt index potential of Phillips (Cr/silica) catalysts.

Rapid activation process and activation treatments for chromium catalysts for producing high melt index polyethylenes

A method comprising a) drying a support material comprising silica at temperature in the range of from about 150&#xb0; C. to about 220&#xb0; C. to form a dried support; b) contacting the dried support with methanol to form a slurried support; c) subsequent to b), cooling the slurried support to a temperature of less than about 60&#xb0; C. to form a cooled slurried support; d) subsequent to c), contacting the cooled slurried support with a titanium alkoxide to form a titanated support; and e) thermally treating the titanated support by heating to a temperature of equal to or greater than about 150&#xb0; C. for a time period of from about 5 hours to about 30 hours to remove the methanol and yield a dried titanated support.

Methods of preparing a catalyst

A method comprising calcining a catalyst precursor comprising chromium and a silica support material at a temperature in the range of from about 95&#xb0; C. to about 400&#xb0; C. in a bed fluidized by a gas flowing at a volumetric flow rate of from about 2.5 to about 30 times the settled volume of the bed per minute to form a calcined catalyst precursor. A method comprising calcining a catalyst precursor comprising chromium and silica at a temperature in the range of from about 95&#xb0; C. to about 400&#xb0; C. with a gas flowing through the bed at a gas hourly space velocity of from about 15 to about 200 per hour. A method comprising calcining a catalyst precursor comprising chromium and silica at a temperature in the range of from about 95&#xb0; C. to about 400&#xb0; C. with a gas flowing through the bed at a weight hourly space velocity of from about 1.9 to about 240 per hour.

Methods for preparing single and dual metallocene catalyst systems containing an activator-support are disclosed. These methods can include precontacting of the activator-support and an organoaluminum compound, as well as sequential contacting of two different metallocene compounds to form a dual metallocene catalyst system.

Processes for preparing metallocene-based catalyst systems

A method comprising a) calcining a silica support at temperature in the range of from about 100&#xb0; C. to about 500&#xb0; C. to form a precalcined silica support; b) contacting the precalcined silica support with a titanium alkoxide to form a titanated support; c) subsequent to b), contacting the titanated support with a polyol to form a polyol associated titanated support (PATS); d) contacting at least one of the silica support, pre-calcined silica support, the titanated support, the PATS, or combinations thereof with a chromium-containing compound to form a polymerization catalyst precursor; e) drying the polymerization catalyst precursor to form a dried polymerization catalyst precursor; and f) calcining the dried polymerization catalyst precursor to produce a polymerization catalyst, wherein less than about 0.1 wt. % of a highly reactive volatile organic compound (HRVOC) is emitted during the calcining of the dried polymerization catalyst precursor.

Methods for controlling properties of an olefin polymer using an alcohol compound are disclosed. The MI and the HLMI of the polymer can be decreased, and the Mw and the Mz of the polymer can be increased, via the addition of the alcohol compound.

Methods of controlling dual catalyst olefin polymerizations with an alcohol compound

The present invention provides dual catalyst systems and polymerization processes employing these dual catalyst systems. The disclosed polymerization processes can produce olefin polymers at higher production rates, and these olefin polymers may have a higher molecular weight and/or a lower melt index.

Dual metallocene catalyst systems for decreasing melt index and increasing polymer production rates

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Seabrook, TX, United States of America

Ted H Cymbaluk