Patents by Inventor Kevin B. Stavens

Kevin B. Stavens has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9815915
    Abstract: A method for preparing a liquid polyolefin includes contacting a feedstock comprising at least one olefin monomer with a catalyst system to produce a reactor effluent stream, filtering the reactor effluent stream, washing a created filter cake with a wash fluid comprising at least one hydrocarbon liquid; and recovering the liquid polyolefin. The catalyst system may be any conventional polyolefin catalyst system, and in a preferred embodiment, the catalyst system contains at least one activated metallocene catalyst. The reactor effluent stream comprises at least one liquid polyolefin, residual catalyst, and unreacted olefin monomer.
    Type: Grant
    Filed: September 3, 2010
    Date of Patent: November 14, 2017
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Kevin B. Stavens, Aaron L. Wetterlind
  • Patent number: 9796645
    Abstract: This invention is directed to a poly alpha olefin (PAO) composition formed in a first oligomerization, wherein at least portions of the PAO have properties that make them highly desirable for a subsequent oligomerization. A preferred process for producing this PAO uses a single site catalyst at high temperatures without adding hydrogen to produce a low viscosity PAO with excellent Noack volatility at high conversion rates. This PAO comprises a dimer product with at least 25 wt % tri-substituted vinylene olefins wherein said dimer product is highly desirable as a feedstock for a subsequent oligomerization. This PAO also comprises trimer and optionally higher oligomer products with outstanding properties that make these products useful as lubricant basestocks following hydrogenation.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: October 24, 2017
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Craig J. Emett, Mark P. Hagemeister, Wenning W. Han, Bruce A. Harrington, Phillip T. Matsunaga, Charles J. Ruff, Kevin B. Stavens, Margaret M. Wu
  • Patent number: 9399746
    Abstract: Poly alpha olefins (PAOs) are characterized by very low viscosity and excellent Noack volatility. A preferred process for synthesizing said PAOs involves first oligomerizing low molecular weight linear alpha olefins in the presence of a single site catalyst at high temperatures without adding hydrogen and then subsequently oligomerizing at least a portion of the product from the first step in the presence of an oligomerization catalyst.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: July 26, 2016
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Craig J. Emett, Mark P. Hagemeister, Bruce A. Harrington, Phillip T. Matsunaga, Pramod J. Nandapurkar, Charles J. Ruff, Kevin B. Stavens
  • Patent number: 9365788
    Abstract: This invention is directed to a two-step process for the preparation of improved poly alpha olefins wherein the first step involves oligomerizing low molecular weight linear alpha olefins in the presence of a single site catalyst and the second step involves oligomerization of at least a portion of the product from the first step in the presence of an oligomerization catalyst. The dimer product from the first oligomerization is characterized by a tri-substituted vinylene olefin content of at least 25 wt %.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: June 14, 2016
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Craig J. Emett, Mark P. Hagemeister, Bruce A. Harrington, Chon Y. Lin, Phillip T. Matsunaga, Charles J. Ruff, Kevin B. Stavens
  • Publication number: 20140323665
    Abstract: A feedstock of one or more C4 to C24 alpha olefins is oligomerized with a metallocene catalyst system to form a polyalphaolefin product mixture. At least a portion of the polyalphaolefin product mixture is then isomerized in the presence of an acid catalyst to form an isomerized polyalphaolefin. The polyalphaolefin may also by hydrogenated, either simultaneously with isomerization or afterwards. The resulting polyalphaolefin has a kinematic viscosity at 100° C. of between 1 cSt and 20 cSt and reduced pour point in comparison to the pre-isomerized product.
    Type: Application
    Filed: February 28, 2012
    Publication date: October 30, 2014
    Applicant: ExxonMobil Chemical Patents Inc.
    Inventors: Margaret M. Wu, Bernie J. Pafford, Kevin B. Stavens
  • Patent number: 8664461
    Abstract: This invention is directed to new mono-cyclopentadienyl (“mono-Cp”) metallocene catalyst compounds useful for producing high viscosity PAOs with narrow molecular weight distribution and good shear stability. Specifically, this invention relates to a group of bridged mono-Cp catalysts wherein, in an embodiment of the invention, the aromatic ring structure is substituted with: 1) at least one phenyl group, 2) at least one alkyl group, and 3) at least one other group, such as a hydrocarbyl group, a heteroatom, or a heteroatom-containing group.
    Type: Grant
    Filed: March 19, 2012
    Date of Patent: March 4, 2014
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Bruce A. Harrington, Abhimanyu O. Patil, Donna J. Crowther, Phillip T. Matsunaga, Kevin B. Stavens, Catalina L. Coker
  • Publication number: 20130253244
    Abstract: This invention is directed to a two-step process for the preparation of improved poly alpha olefins wherein the first step involves oligomerizing low molecular weight linear alpha olefins in the presence of a single site catalyst and the second step involves oligomerization of at least a portion of the product from the first step in the presence of an oligomerization catalyst. The dimer product from the first oligomerization is characterized by a tri-substituted vinylene olefin content of at least 25 wt %.
    Type: Application
    Filed: September 12, 2012
    Publication date: September 26, 2013
    Inventors: Craig J. Emett, Mark P. Hagemeister, Bruce A. Harrington, Chon Y. Lin, Phillip T. Matsunaga, Charles J. Ruff, Kevin B. Stavens
  • Publication number: 20130245344
    Abstract: Poly alpha olefins (PAOs) are characterized by very low viscosity and excellent Noack volatility. A preferred process for synthesizing said PAOs involves first oligomerizing low molecular weight linear alpha olefins in the presence of a single site catalyst at high temperatures without adding hydrogen and then subsequently oligomerizing at least a portion of the product from the first step in the presence of an oligomerization catalyst.
    Type: Application
    Filed: September 12, 2012
    Publication date: September 19, 2013
    Inventors: Craig J. Emett, Mark P. Hagemeister, Bruce A. Harrington, Phillip T. Matsunga, Pramod J. Nandapurkar, Charles J. Ruff, Kevin B. Stavens
  • Publication number: 20130245343
    Abstract: This invention is directed to a poly alpha olefin (PAO) composition formed in a first oligomerization, wherein at least portions of the PAO have properties that make them highly desirable for a subsequent oligomerization. A preferred process for producing this PAO uses a single site catalyst at high temperatures without adding hydrogen to produce a low viscosity PAO with excellent Noack volatility at high conversion rates. This PAO comprises a dimer product with at least 25 wt % tri-substituted vinylene olefins wherein said dimer product is highly desirable as a feedstock for a subsequent oligomerization. This PAO also comprises trimer and optionally higher oligomer products with outstanding properties that make these products useful as lubricant basestocks following hydrogenation.
    Type: Application
    Filed: September 12, 2012
    Publication date: September 19, 2013
    Inventors: Craig J. Emett, Mark P. Hagemeister, Wenning W. Han, Bruce A. Harrington, Phillip T. Matsunaga, Charles J. Ruff, Kevin B. Stavens, Margaret M. Wu
  • Publication number: 20130245213
    Abstract: This invention is directed to new mono-cyclopentadienyl (“mono-Cp”) metallocene catalyst compounds useful for producing high viscosity PAOs with narrow molecular weight distribution and good shear stability. Specifically, this invention relates to a group of bridged mono-Cp catalysts wherein, in an embodiment of the invention, the aromatic ring structure is substituted with: 1) at least one phenyl group, 2) at least one alkyl group, and 3) at least one other group, such as a hydrocarbyl group, a heteroatom, or a heteroatom-containing group.
    Type: Application
    Filed: March 19, 2012
    Publication date: September 19, 2013
    Inventors: Bruce A. Harrington, Abhimanyu O. Patil, Donna J. Crowther, Phillip T. Matsunaga, Kevin B. Stavens, Catalina L. Coker
  • Publication number: 20130210996
    Abstract: A polyalphaolefin polymer, having a kinematic viscosity at 100° C. of 135 cSt or greater, is shear stable. The polymer either has not more than 0.5 wt % of the polymer having a molecular weight of greater than 60,000 Daltons, or after being subjected to twenty hours of taper roller bearing testing, the polymer has a kinematic viscosity loss of less than 9%. Such a shear stable polyalphaolefin is obtained by either mechanical breakdown of a high viscosity polyalphaolefin or by a selective catalyst system used in oligomerization or polymerization of the feedstock.
    Type: Application
    Filed: June 30, 2011
    Publication date: August 15, 2013
    Applicant: ExxonMobil Chemical Company - Law Technology
    Inventors: Margaret May-Som Wu, Kevin B. Stavens, Wenning W. Han, Abhimanyu O. Patil
  • Patent number: 8192690
    Abstract: A method of treating a gas phase fluidized bed reactor and a method of polymerizing olefins in a gas phase fluidized bed reactor in the presence of a catalyst prone to cause sheeting by introducing a chromium-containing compound into the reactor and forming a high molecular weight polymer coating on the walls of the reactor. Furthermore, a device for and method of introducing the chromium-containing compound into the fluidized bed reactor at a plurality of locations in proximity to a lower section of a bed section wall of the fluidized bed reactor, and forming a high molecular weight polymer coating on the bed section wall.
    Type: Grant
    Filed: October 20, 2011
    Date of Patent: June 5, 2012
    Assignee: Univation Technologies, LLC
    Inventors: Agapios K. Agapiou, David M. Glowczwski, Zerong Lin, Gary D. Mohr, Ted A. Powell, Michael E. Sieloff, Edward F. Smith, Kevin B. Stavens, Keith W. Trapp, Michael E. Muhle, F. David Hussein
  • Publication number: 20120070575
    Abstract: A method for treating at least one interior surface (for example, a bed wall) of a fluidized bed polymerization reactor system, including by applying a solution catalyst (preferably at least substantially uniformly and in liquid form) to each surface, and optionally (where a catalyst component of the solution catalyst comprises at least one chromium containing compound) oxidizing at least some of the applied chromium containing compound in a controlled manner.
    Type: Application
    Filed: November 22, 2011
    Publication date: March 22, 2012
    Applicant: UNIVATION TECHNOLOGIES, LLC
    Inventors: Robert O. Hagerty, Kevin B. Stavens, Randall B. Laird, Zerong Lin, Michael E. Muhle, Agapios K. Agapiou, David M. Glowczwski, Fathi D. Hussein, Gary D. Mohr, Ted A. Powell, Michael E. Sieloff, Edward F. Smith, Keith W. Trapp
  • Publication number: 20120059207
    Abstract: A method for preparing a liquid polyolefin includes contacting a feedstock comprising at least one olefin monomer with a catalyst system to produce a reactor effluent stream, filtering the reactor effluent stream, washing a created filter cake with a wash fluid comprising at least one hydrocarbon liquid; and recovering the liquid polyolefin. The catalyst system may be any conventional polyolefin catalyst system, and in a preferred embodiment, the catalyst system contains at least one activated metallocene catalyst. The reactor effluent stream comprises at least one liquid polyolefin, residual catalyst, and unreacted olefin monomer.
    Type: Application
    Filed: September 3, 2010
    Publication date: March 8, 2012
    Inventors: Kevin B. Stavens, Aaron L. Wetterlind
  • Patent number: 8129481
    Abstract: A method for treating at least one interior surface (for example, a bed wall) of a fluidized bed polymerization reactor system, including by applying a solution catalyst (preferably at least substantially uniformly and in liquid form) to each surface, and optionally (where a catalyst component of the solution catalyst comprises at least one chromium containing compound) oxidizing at least some of the applied chromium containing compound in a controlled manner.
    Type: Grant
    Filed: November 22, 2011
    Date of Patent: March 6, 2012
    Assignee: Univation Technologies, LLC
    Inventors: Robert O. Hagerty, Kevin B. Stavens, Randall B. Laird, Zerong Lin, Michael E. Muhle, Agapios K. Agapiou, David M. Glowczwski, Fathi D. Hussein, Gary D. Mohr, Ted A. Powell, Michael E. Sieloff, Edward F. Smith, Keith W. Trapp
  • Publication number: 20120039755
    Abstract: A method of treating a gas phase fluidized bed reactor and a method of polymerizing olefins in a gas phase fluidized bed reactor in the presence of a catalyst prone to cause sheeting by introducing a chromium-containing compound into the reactor and forming a high molecular weight polymer coating on the walls of the reactor. Furthermore, a device for and method of introducing the chromium-containing compound into the fluidized bed reactor at a plurality of locations in proximity to a lower section of a bed section wall of the fluidized bed reactor, and forming a high molecular weight polymer coating on the bed section wall.
    Type: Application
    Filed: October 20, 2011
    Publication date: February 16, 2012
    Applicant: UNIVATION TECHNOLOGIES, LLC
    Inventors: Agapios K. Agapiou, David M. Glowczwski, Zerong Lin, Gary D. Mohr, Ted A. Powell, Michael E. Sieloff, Edward F. Smith, Kevin B. Stavens, Keith W. Trapp, Michael E. Muhle, F. David Hussein
  • Patent number: 8088870
    Abstract: A method for treating at least one interior surface (for example, a bed wall) of a fluidized bed polymerization reactor system, including by applying a solution catalyst (preferably at least substantially uniformly and in liquid form) to each surface, and optionally (where a catalyst component of the solution catalyst comprises at least one chromium containing compound) oxidizing at least some of the applied chromium containing compound in a controlled manner.
    Type: Grant
    Filed: February 21, 2008
    Date of Patent: January 3, 2012
    Assignee: Univation Technologies, LLC
    Inventors: Robert O. Hagerty, Kevin B. Stavens, Randall B. Laird, Zerong Lin, Michael E. Muhle, Agapios K. Agapiou, David M. Glowczwski, Fathi D. Hussein, Gary D. Mohr, Ted A. Powell, Michael E. Sieloff, Edward F. Smith, Keith W. Trapp
  • Patent number: 8084554
    Abstract: A method of treating a gas phase fluidized bed reactor and a method of polymerizing olefins in a gas phase fluidized bed reactor in the presence of a catalyst prone to cause sheeting by introducing a chromium-containing compound into the reactor and forming a high molecular weight polymer coating on the walls of the reactor. Furthermore, a device for and method of introducing the chromium-containing compound into the fluidized bed reactor at a plurality of locations in proximity to a lower section of a bed section wall of the fluidized bed reactor, and forming a high molecular weight polymer coating on the bed section wall.
    Type: Grant
    Filed: February 11, 2008
    Date of Patent: December 27, 2011
    Assignee: Univation Technologies, LLC
    Inventors: Agapios K. Agapiou, David M. Glowczwski, Zerong Lin, Gary D. Mohr, Ted A. Powell, Michael E. Sieloff, Edward F. Smith, Kevin B. Stavens, Keith W. Trapp, Michael E. Muhle, F. David Hussein
  • Patent number: 7875685
    Abstract: Apparatus and methods for gas phase polymerization are provided. The method can include polymerizing one or more olefins at gas phase conditions in a reactor comprising one or more process exposed surfaces in the presence of a catalyst system; and treating at least a portion of the one or more process exposed surfaces prior to injecting the catalyst system to reduce the number of surface hydroxyls or access of the catalyst system to the surface hydroxyls on the process exposed surfaces.
    Type: Grant
    Filed: November 7, 2007
    Date of Patent: January 25, 2011
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Kevin B. Stavens, Matthew W. Holtcamp, Gary D. Mohr, William A. Lamberti
  • Patent number: 7858719
    Abstract: The present invention relates to a gas phase process for polymerizing one or more hydrocarbon monomer(s) in the presence of a catalyst system and a fluorinated hydrocarbon, where the fluorinated hydrocarbon is present at a partial pressure of 6.9 to 348 kPa in the reactor and the reactor temperature is from 30 to 120° C.
    Type: Grant
    Filed: May 19, 2005
    Date of Patent: December 28, 2010
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Robert Olds Hagerty, Kevin B. Stavens, Randall B. Laird, Michael F. McDonald, Pradeep P. Shirodkar