Patents by Inventor Kamala Krishna

Kamala Krishna 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: 9809760
    Abstract: A method for producing a base oil having a high ratio of weight percent molecules with monocycloparaffinic functionality to weight percent molecules with multicycloparaffinic functionality by hydroisomerization dewaxing a selected Fischer-Tropsch wax under hydroisomerization conditions including a hydrogen to feed ratio from about 712.4 to about 3562 liter H2/liter oil.
    Type: Grant
    Filed: June 26, 2009
    Date of Patent: November 7, 2017
    Assignee: Chevron U.S.A. Inc.
    Inventors: John M. Rosenbaum, Nancy J. Bertrand, Scott C. Deskin, Kamala Krishna, Stephen J. Miller, Susan M. Abernathy
  • Publication number: 20170275539
    Abstract: Processes and catalyst systems are provided for dewaxing a hydrocarbon feedstock to form a lubricant base oil. A layered catalyst system of the present invention may comprise a first hydroisomerization dewaxing catalyst disposed upstream from a second hydroisomerization dewaxing catalyst. Each of the first and second hydroisomerization dewaxing catalysts may be selective for the isomerization of n-paraffins. The first hydroisomerization catalyst may have a higher level of selectivity for the isomerization of n-paraffins than the second hydroisomerization dewaxing catalyst. At least one of the first and second hydroisomerization dewaxing catalysts comprises small crystallite zeolite SSZ-32x.
    Type: Application
    Filed: June 13, 2017
    Publication date: September 28, 2017
    Inventors: Kamala Krishna, Guan-Dao Lei
  • Patent number: 9677016
    Abstract: Processes and catalyst systems are provided for dewaxing a hydrocarbon feedstock to form a lubricant base oil. A layered catalyst system of the present invention may comprise a first hydroisomerization dewaxing catalyst disposed upstream from a second hydroisomerization dewaxing catalyst. Each of the first and second hydroisomerization dewaxing catalysts may be selective for the isomerization of n-paraffins. The first hydroisomerization catalyst may have a higher level of selectivity for the isomerization of n-paraffins than the second hydroisomerization dewaxing catalyst. At least one of the first and second hydroisomerization dewaxing catalysts comprises small crystallite zeolite SSZ-32x.
    Type: Grant
    Filed: June 9, 2014
    Date of Patent: June 13, 2017
    Assignee: Chevron U.S.A. Inc.
    Inventors: Kamala Krishna, Guan-Dao Lei
  • Patent number: 8882989
    Abstract: A lubricating base oil manufacturing plant comprising a means for hydroisomerization dewaxing a wax at a specified hydrogen to feed ratio and a means for hydrofinishing the hydroisomerized wax to produce one or more base oils having greater than 10 weight percent total molecules with cycloparaffinic functionality and less than 0.5 weight percent molecules with multicycloparaffinic functionality.
    Type: Grant
    Filed: June 26, 2009
    Date of Patent: November 11, 2014
    Assignee: Chevron U.S.A. Inc.
    Inventors: John M. Rosenbaum, Nancy J. Bertrand, Scott C. Deskin, Kamala Krishna, Stephen J. Miller, Susan M. Abernathy
  • Publication number: 20140291206
    Abstract: Processes and catalyst systems are provided for dewaxing a hydrocarbon feedstock to form a lubricant base oil. A layered catalyst system of the present invention may comprise a first hydroisomerization dewaxing catalyst disposed upstream from a second hydroisomerization dewaxing catalyst. Each of the first and second hydroisomerization dewaxing catalysts may be selective for the isomerization of n-paraffins. The first hydroisomerization catalyst may have a higher level of selectivity for the isomerization of n-paraffins than the second hydroisomerization dewaxing catalyst. At least one of the first and second hydroisomerization dewaxing catalysts comprises small crystallite zeolite SSZ-32x.
    Type: Application
    Filed: June 9, 2014
    Publication date: October 2, 2014
    Applicant: CHEVRON U.S.A. INC.
    Inventors: Kamala Krishna, Guan-Dao Lei
  • Patent number: 8790507
    Abstract: Processes and catalyst systems are provided for dewaxing a hydrocarbon feedstock to form a lubricant base oil. A layered catalyst system of the present invention may comprise a first hydroisomerization dewaxing catalyst disposed upstream from a second hydroisomerization dewaxing catalyst. Each of the first and second hydroisomerization dewaxing catalysts may be selective for the isomerization of n-paraffins. The first hydroisomerization catalyst may have a higher level of selectivity for the isomerization of n-paraffins than the second hydroisomerization dewaxing catalyst. At least one of the first and second hydroisomerization dewaxing catalysts comprises small crystallite zeolite SSZ-32x.
    Type: Grant
    Filed: June 14, 2011
    Date of Patent: July 29, 2014
    Assignee: Chevron U.S.A. Inc.
    Inventors: Kamala Krishna, Guan-Dao Lei
  • Patent number: 8617387
    Abstract: Processes and catalyst systems are provided for dewaxing a light hydrocarbon feedstock to form a lubricant base oil. A layered catalyst system of the present invention may comprise a first hydroisomerization dewaxing catalyst disposed upstream from a second hydroisomerization dewaxing catalyst. Each of the first and second hydroisomerization dewaxing catalysts may be selective for the isomerization of n-paraffins. The first hydroisomerization catalyst may have a higher level of selectivity for the isomerization of n-paraffins than the second hydroisomerization dewaxing catalyst.
    Type: Grant
    Filed: June 14, 2011
    Date of Patent: December 31, 2013
    Assignee: Chevron U.S.A. Inc.
    Inventors: Kamala Krishna, Guan-Dao Lei
  • Patent number: 8475648
    Abstract: Processes and catalyst systems are provided for dewaxing a heavy hydrocarbon feedstock to form a lubricant base oil. A layered catalyst system of the present invention may comprise a first hydroisomerization dewaxing catalyst disposed upstream from a second hydroisomerization dewaxing catalyst. Each of the first and second hydroisomerization dewaxing catalysts may be selective for the isomerization of n-paraffins. The first hydroisomerization catalyst has a first level of selectivity for the isomerization of n-paraffins, the second hydroisomerization dewaxing catalyst has a second level of selectivity for the isomerization of n-paraffins, and a layered catalyst system comprising the first and second hydroisomerization dewaxing catalysts has a third level of selectivity for the isomerization of n-paraffins. The third level of selectivity may be higher than each of the first level of selectivity and the second level of selectivity.
    Type: Grant
    Filed: June 14, 2011
    Date of Patent: July 2, 2013
    Assignee: Chevron U.S.A. Inc.
    Inventors: Kamala Krishna, Guan-Dao Lei
  • Publication number: 20110315597
    Abstract: Processes and catalyst systems are provided for dewaxing a heavy hydrocarbon feedstock to form a lubricant base oil. A layered catalyst system of the present invention may comprise a first hydroisomerization dewaxing catalyst disposed upstream from a second hydroisomerization dewaxing catalyst. Each of the first and second hydroisomerization dewaxing catalysts may be selective for the isomerization of n-paraffins. The first hydroisomerization catalyst has a first level of selectivity for the isomerization of n-paraffins, the second hydroisomerization dewaxing catalyst has a second level of selectivity for the isomerization of n-paraffins, and a layered catalyst system comprising the first and second hydroisomerization dewaxing catalysts has a third level of selectivity for the isomerization of n-paraffins. The third level of selectivity may be higher than each of the first level of selectivity and the second level of selectivity.
    Type: Application
    Filed: June 14, 2011
    Publication date: December 29, 2011
    Applicant: Chevron U.S.A. Inc
    Inventors: Kamala Krishna, Guan-Dao Lei
  • Publication number: 20110319685
    Abstract: Processes and catalyst systems are provided for dewaxing a light hydrocarbon feedstock to form a lubricant base oil. A layered catalyst system of the present invention may comprise a first hydroisomerization dewaxing catalyst disposed upstream from a second hydroisomerization dewaxing catalyst. Each of the first and second hydroisomerization dewaxing catalysts may be selective for the isomerization of n-paraffins. The first hydroisomerization catalyst may have a higher level of selectivity for the isomerization of n-paraffins than the second hydroisomerization dewaxing catalyst.
    Type: Application
    Filed: June 14, 2011
    Publication date: December 29, 2011
    Applicant: Chevron U.S.A. Inc
    Inventors: Kamala Krishna, Guan-Dao Lei
  • Publication number: 20110315598
    Abstract: Processes and catalyst systems are provided for dewaxing a hydrocarbon feedstock to form a lubricant base oil. A layered catalyst system of the present invention may comprise a first hydroisomerization dewaxing catalyst disposed upstream from a second hydroisomerization dewaxing catalyst. Each of the first and second hydroisomerization dewaxing catalysts may be selective for the isomerization of n-paraffins. The first hydroisomerization catalyst may have a higher level of selectivity for the isomerization of n-paraffins than the second hydroisomerization dewaxing catalyst. At least one of the first and second hydroisomerization dewaxing catalysts comprises small crystallite zeolite SSZ-32x.
    Type: Application
    Filed: June 14, 2011
    Publication date: December 29, 2011
    Applicant: Chevron U.S.A. Inc
    Inventors: Kamala Krishna, Guan-Dao Lei
  • Publication number: 20110008219
    Abstract: A lubricating base oil manufacturing plant comprising a means for hydroisomerization dewaxing a wax at a specified hydrogen to feed ratio and a means for hydrofinishing the hydroisomerized wax to produce one or more base oils having a viscosity index greater than 28×Ln(Kinematic Viscosity at 100° C., in cSt)+95, and a ratio of wt % molecules with monocycloparaffinic functionality to wt % molecules with multicycloparaffinic functionality greater than 15.
    Type: Application
    Filed: September 3, 2010
    Publication date: January 13, 2011
    Inventors: John M. Rosenbaum, Nancy J. Bertrand, Scott Deskin, Kamala Krishna, Stephen J. Miller, Susan M. Abernathy
  • Patent number: 7763161
    Abstract: A process for manufacturing a lubricating base oil, comprising dewaxing a substantially paraffinic wax feed by hydroisomerization dewaxing using a shape selective intermediate pore size molecular sieve under hydroisomerization conditions including a hydrogen to feed ratio from about 712.4 to about 3562 liter H2/liter oil, whereby a lubricating base oil is produced having a) a total weight percent of molecules with cycloparaffinic functionality greater than 10, and b) a ratio of weight percent molecules with monocycloparaffinic functionality to weight percent molecules with multicycloparaffinic functionality greater than 30. Also a method for producing a base oil having a high ratio of weight percent molecules with monocycloparaffinic functionality to weight percent molecules with multicycloparaffinic functionality by hydroisomerization dewaxing a selected Fischer-Tropsch wax under hydroisomerization conditions including a hydrogen to feed ratio from about 712.4 to about 3562 liter H2/liter oil.
    Type: Grant
    Filed: May 19, 2006
    Date of Patent: July 27, 2010
    Assignee: Chevron U.S.A. Inc.
    Inventors: John M. Rosenbaum, Nancy J. Bertrand, Scott Deskin, Kamala Krishna, Stephen J. Miller, Susan M. Abernathy
  • Publication number: 20090321308
    Abstract: A method for producing a base oil having a high ratio of weight percent molecules with monocycloparaffinic functionality to weight percent molecules with multicycloparaffinic functionality by hydroisomerization dewaxing a selected Fischer-Tropsch wax under hydroisomerization conditions including a hydrogen to feed ratio from about 712.4 to about 3562 liter H2/liter oil.
    Type: Application
    Filed: June 26, 2009
    Publication date: December 31, 2009
    Inventors: John M. Rosenbaum, Nancy J. Bertrand, Scott C. Deskin, Kamala Krishna, Stephen J. Miller, Susan M. Abernathy
  • Publication number: 20090321307
    Abstract: A lubricating base oil manufacturing plant comprising a means for hydroisomerization dewaxing a wax at a specified hydrogen to feed ratio and a means for hydrofinishing the hydroisomerized wax to produce one or more base oils having greater than 10 weight percent total molecules with cycloparaffinic functionality and less than 0.5 weight percent molecules with multicycloparaffinic functionality.
    Type: Application
    Filed: June 26, 2009
    Publication date: December 31, 2009
    Inventors: John M. Rosenbaum, Nancy J. Bertrand, Scott C. Deskin, Kamala Krishna, Stephen J. Miller, Susan M. Abernathy
  • Patent number: 7569507
    Abstract: The invention is directed to a method of making a small crystal SSZ-32 zeolite, known as SSZ-32X. The catalyst is suitable for use in a process whereby a feed including straight chain and slightly branched paraffins having 10 or more carbon atoms is dewaxed to produce an isomerized product, with increased yield of isomerized material and decreased production of light ends.
    Type: Grant
    Filed: August 24, 2006
    Date of Patent: August 4, 2009
    Assignee: Chevron U.S.A., Inc.
    Inventors: Stacey I. Zones, Guang Zhang, Kamala Krishna, Joseph A. Biscardi, Paul Marcantonio, Euthimios Vittoratos
  • Patent number: 7468126
    Abstract: The invention is directed to a method of making a small crystal SSZ-32 zeolite, known as SSZ-32X. The catalyst is suitable for use in a process whereby a feed including straight chain and slightly branched paraffins having 10 or more carbon atoms is dewaxed to produce an isomerized product, with increased yield of isomerized material and decreased production of light ends.
    Type: Grant
    Filed: August 24, 2006
    Date of Patent: December 23, 2008
    Assignee: Chevron U.S.A., Inc.
    Inventors: Stacey I. Zones, Guang Zhang, Kamala Krishna, Joseph A. Biscardi, Paul Marcantonio, Euthimios Vittoratos
  • Publication number: 20080083657
    Abstract: Dewaxing a hydrocarbon feed by isomerizing feed with catalyst comprising small crystallite molecular sieve having MTT framework, the catalyst containing at least one metal selected from the group consisting of Ca, Cr, Mg, La, Na, Pr, Sr, K and Nd, and at least one Group VIII metal. A dewaxing method to produce products boiling at 343° C. (650° F.) or higher with low pour points and high viscosity indexes wherein the line fit to the chart of the pour points and the viscosity indexes has a slope of zero or less. A dewaxing process, comprising isomerization dewaxing feed with a viscosity at 100° C. of 2.5 mm2/s or greater over a metal-modified molecular sieve to produce products with low pour points and high viscosity indexes; the line fit to the chart of the pour points and the viscosity indexes has a slope of zero or less; and wherein the yield of products is high.
    Type: Application
    Filed: October 2, 2007
    Publication date: April 10, 2008
    Inventors: Stacey I. Zones, Kamala Krishna
  • Publication number: 20070048214
    Abstract: The invention is directed to a method of making a small crystal SSZ-32 zeolite, known as SSZ-32X. The catalyst is suitable for use in a process whereby a feed including straight chain and slightly branched paraffins having 10 or more carbon atoms is dewaxed to produce an isomenized product, with increased yield of isomerized material and decreased production of light ends.
    Type: Application
    Filed: August 24, 2006
    Publication date: March 1, 2007
    Inventors: Stacey Zones, Guang Zhang, Kamala Krishna, Joseph Biscardi, Paul Marcantonio, Euthimios Vittoratos
  • Publication number: 20070041898
    Abstract: The invention is directed to a method of making a small crystal SSZ-32 zeolite, known as SSZ-32X. The catalyst is suitable for use in a process whereby a feed including straight chain and slightly branched paraffins having 10 or more carbon atoms is dewaxed to produce an isomerized product, with increased yield of isomerized material and decreased production of light ends.
    Type: Application
    Filed: August 24, 2006
    Publication date: February 22, 2007
    Inventors: Stacey Zones, Guang Zhang, Kamala Krishna, Joseph Biscardi, Paul Marcantonio, Euthimios Vittoratos