Patents by Inventor Vasant P. Thakkar

Vasant P. Thakkar 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: 7094332
    Abstract: A hydrocracking process to produce ultra low sulfur diesel by reacting a first hydrocarbon feedstock in a hydrocracking zone, introducing the hydrocracking zone effluent and a second hydrocarbon feedstock having a majority boiling at a temperature greater than 565° C. (1050° F.) into a first desulfurization zone, passing the first desulfurization zone effluent to a hot, high pressure vapor-liquid separator to recover a vaporous hydrocarbonaceous stream and a first liquid hydrocarbonaceous stream, introducing the vaporous hydrocarbonaceous stream and a third hydrocarbonaceous feedstock comprising diesel into a second desulfurization zone, passing the second desulfurization zone effluent to a cold vapor-liquid separator to provide a hydrogen-rich gaseous stream and a second liquid hydrocarbonaceous stream and passing the first and the second liquid hydrocarbonaceous streams to a fractionation zone to produce ultra low sulfur diesel.
    Type: Grant
    Filed: May 6, 2003
    Date of Patent: August 22, 2006
    Assignee: UOP LLC
    Inventors: Tom N. Kalnes, Vasant P. Thakkar
  • Patent number: 6689273
    Abstract: Heavy hydrocarbons are upgraded to higher value distillates in a hydrocarbon conversion process which employs several parallel on-stream reaction zones which each contain both hydrotreating and hydrocracking catalyst beds. The feed and liquid recycled from the bottom of the reaction zone is charged to the top of the uppermost catalyst bed. Hydrogen flow in the reaction zones is countercurrent to the descending liquid, and products are removed as vapor. The flow of feed to one of the reaction zones is periodically stopped to allow sequential on-stream hydrogenative regeneration of the catalysts within the reaction zones. This allows continuous commercial operation at conditions which are otherwise unfeasible.
    Type: Grant
    Filed: November 6, 2001
    Date of Patent: February 10, 2004
    Assignee: UOP LLC
    Inventors: Tom N. Kalnes, Stephen R. Dunne, Vasant P. Thakkar
  • Patent number: 6638418
    Abstract: A dual recycle catalytic hydrocracking process for the production of ultra low sulfur diesel while simultaneously processing two feedstocks. One preferred feedstock boils in the temperature range of diesel and the second preferred feedstock boils in the temperature range above that of diesel.
    Type: Grant
    Filed: November 7, 2001
    Date of Patent: October 28, 2003
    Assignee: UOP LLC
    Inventors: Tom N. Kalnes, Vasant P. Thakkar, Richard K. Hoehn
  • Patent number: 6517705
    Abstract: A catalytic hydrocracking process for the production of lube base oil wherein a hydrocarbonaceous feedstock is contacted with hydrogen and a metal promoted hydrocracking catalyst in a hydrocracking reaction zone at elevated temperature and pressure to obtain conversion to higher hydrogen-content hydrocarbons including lube base oil. The resulting hot, uncooled effluent from the hydrocracking reaction zone is hydrogen stripped in a hot, high pressure stripping zone maintained at essentially the same pressure as the hydrocracking zone to produce a first gaseous hydrocarbonaceous stream and a first liquid hydrocarbonaceous stream. At least a portion of the first gaseous hydrocarbonaceous stream is condensed to produce a second liquid hydrocarbonaceous stream and a second hydrogen-rich gaseous stream. The first liquid hydrocarbonaceous stream is preferably separated at a pressure greater than atmospheric pressure to provide at least one lube base oil product stream.
    Type: Grant
    Filed: March 21, 2001
    Date of Patent: February 11, 2003
    Assignee: UOP LLC
    Inventors: Tom N. Kalnes, Vasant P. Thakkar
  • Patent number: 6432297
    Abstract: A process for the production of lube oil basestock wherein a high boiling hydrocarbonaceous feedstock is hydrocracked to produce hydrocarbons boiling in the range of lube oil basestock and the resulting hydrocracker effluent is hot, hydrogen stripped to remove lower boiling hydrocarbons and hydrogen sulfide before being introduced into a hydrodewaxing zone. In a preferred embodiment the hot hydrogen stripper contains a hydrogenation zone conducted at “sweet” hydrogenating conditions which permits the subsequent use of sulfur sensitive catalysts in downstream reaction zones including hydrodewaxing and hydrofinishing reaction zones. Preferably, the effluent from the hydrodewaxing reaction zone is immediately further processed in a hydrofinishing reaction zone.
    Type: Grant
    Filed: October 23, 2000
    Date of Patent: August 13, 2002
    Assignee: UOP LLC
    Inventors: Tom N. Kalnes, Vasant P. Thakkar
  • Patent number: 6379533
    Abstract: A catalytic hydrocracking process which provides for the simultaneous production of LPG and distillate hydrocarbons. The feedstock is introduced into a denitrification and desulfurization zone and then passed directly to a hot, high pressure stripper utilizing a hot, hydrogen-rich stripping gas to produce a first liquid stream boiling in the range of the feedstock and a first vapor stream comprising hydrocarbonaceous compounds boiling at a temperature below the boiling range of the feedstock. The first liquid stream is hydrocracked in a first hydrocracking zone and then passed to the denitrification and desulfurization zone. At least a portion of the first vapor stream is condensed to produce a second liquid stream comprising hydrocarbonaceous compounds boiling at a temperature below the boiling range of the feedstock.
    Type: Grant
    Filed: December 18, 2000
    Date of Patent: April 30, 2002
    Assignee: UOP LLC
    Inventors: Vasant P. Thakkar, Tom N. Kalnes, Richard K. Hoehn
  • Patent number: 6315889
    Abstract: A feed stream is processed in a hydrotreating reaction zone and then the hydrotreating effluent is separated into two fractions in a first high pressure separator. The vapor fraction is passed into a second high pressure separator. A controlled portion of the liquid fraction from the first high pressure separator and the liquid from the second high pressure separator are passed into a hydrocracking zone. The remaining portion of the liquid from the first high pressure separator is passed into the product recovery zone.
    Type: Grant
    Filed: October 21, 1999
    Date of Patent: November 13, 2001
    Assignee: UOP LLC
    Inventors: Vasant P. Thakkar, Christopher J. Anderle, Hemant B. Gala
  • Patent number: 6312586
    Abstract: Heavy hydrocarbons are upgraded to higher value distillates in a hydrocarbon conversion process which employs several parallel reaction zones which each contain both hydrotreating and hydrocracking catalyst beds. The feed and liquid recycle from the bottom of the reaction zone is charged to the top of the uppermost catalyst bed. Hydrogen flow is countercurrent to the descending liquid, and products are removed overhead through vapor-liquid contactors. The flow of feed to one of the reaction zones is periodically stopped to allow sequential on-stream hydrogenative regeneration of the catalysts within the reaction zone.
    Type: Grant
    Filed: September 27, 1999
    Date of Patent: November 6, 2001
    Assignee: UOP LLC
    Inventors: Tom N. Kalnes, Stephen R. Dunne, Vasant P. Thakkar
  • Patent number: 6296758
    Abstract: A hydrocracking process wherein a hydrocarbonaceous feedstock and a hot hydrocracking zone effluent containing hydrogen is passed to a denitrification and desulfurization reaction zone to produce hydrogen sulfide and ammonia to thereby clean up the fresh feedstock. The resulting hot, uncooled effluent from the denitrification and desulfurization zone is hydrogen stripped in a stripping zone maintained at essentially the same pressure as the preceding reaction zone with a hydrogen-rich gaseous stream to produce a vapor stream comprising hydrogen, hydrocarbonaceous compounds boiling at a temperature below the boiling range of the fresh feedstock, hydrogen sulfide and ammonia, and a liquid hydrocarbonaceous stream.
    Type: Grant
    Filed: June 23, 1999
    Date of Patent: October 2, 2001
    Assignee: UOP LLC
    Inventors: Tom N. Kalnes, Vasant P. Thakkar
  • Patent number: 6294080
    Abstract: A feed stream is first processed in a hydrotreating reaction zone and then the effluent is separated into three fractions in an augmented first high pressure separator. Controlled portions of the middle and heavy boiling point range hydrocarbon fractions from this separator are recycled through a low conversion hydrocracking zone, while the remaining portions of these two fractions are passed into a second high pressure separator for recovery. The recycled hydrocarbons flow into a hydrocracking zone and the effluent of this zone flows into the hydrotreating reaction zone.
    Type: Grant
    Filed: October 21, 1999
    Date of Patent: September 25, 2001
    Assignee: UOP LLC
    Inventors: Vasant P. Thakkar, Christopher J. Anderle
  • Patent number: 6294079
    Abstract: A feed stream is first processed in a hydrotreating reaction zone and then the effluent is separated into three fractions in an augmented first high pressure separator. Controlled portions of the middle and heavy hydrocarbon fractions are passed into a high severity hydrocracking zone, while the remaining portions of these two fractions are passed into a second high pressure separator for recovery. The effluent of the hydrocracking zone is also fed to the second high pressure separator.
    Type: Grant
    Filed: October 21, 1999
    Date of Patent: September 25, 2001
    Assignee: UOP LLC
    Inventors: Vasant P. Thakkar, Christopher J. Anderle, Hemant B. Gala
  • Patent number: 6217746
    Abstract: A two stage hydrocracking process is characterized by operation of the second hydrocracking zone at a reduced pressure, which is conducive to cracking the highly paraffinic effluent of the first hydrocracking zone. The process is also characterized by the passage of the partially compressed hydrogen makeup gas stream into the second hydrocracking zone followed by compressing the gas recovered from the second hydrocracking zone effluent to form the makeup gas to the first stage hydrocracking zone. There is no recycle gas stream for the second hydrocracking zone.
    Type: Grant
    Filed: August 16, 1999
    Date of Patent: April 17, 2001
    Assignee: UOP LLC
    Inventors: Vasant P. Thakkar, Daniel L. Ellig
  • Patent number: 6106694
    Abstract: A hydrocracking process wherein a hydrocarbonaceous feedstock and a hot hydrocracking zone effluent containing hydrogen is passed to a denitrification and desulfurization reaction zone to produce hydrogen sulfide and ammonia to thereby clean up the fresh feedstock. The resulting hot, uncooled effluent from the denitrification and desulfurization zone is hydrogen stripped in a stripping zone maintained at essentially the same pressure as the preceding reaction zone with a hydrogen-rich gaseous stream to produce a vapor stream comprising hydrogen, hydrocarbonaceous compounds boiling at a temperature below the boiling range of the fresh feedstock, hydrogen sulfide and ammonia, and a liquid hydrocarbonaceous stream.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: August 22, 2000
    Assignee: Uop LLC
    Inventors: Tom N. Kalnes, Vasant P. Thakkar
  • Patent number: 6106695
    Abstract: A process to provide a multiplicity of hydrocracking reaction zones containing hydrocracking catalyst wherein the catalyst is rejuvenated or reactivated while the process unit remains on-stream by the periodic exposure of partially spent catalyst to hot recycle gas containing hydrogen. The hydrocracking catalyst always operates at "near" fresh activity and selectivity thereby resulting in more stable temperature, yield and product quality performance.
    Type: Grant
    Filed: March 22, 1999
    Date of Patent: August 22, 2000
    Assignee: UOP LLC
    Inventors: Tom N. Kalnes, Vasant P. Thakkar
  • Patent number: 5985132
    Abstract: A process for the simultaneous production of lubricating blending stocks by means of hydrocracking a hydrocarbon feedstock in a first hydrocracking zone to convert at least a portion of the heavy hydrocarbon feedstock to produce an effluent stream containing lube oil boiling range hydrocarbons. One portion of the effluent stream is directly removed from the first hydrocracking zone to produce high quality lube oil blending stocks. Another portion of the effluent stream from the first hydrocracking zone is directly introduced into a second hydrocracking zone without intermediate separation. The second hydrocracking zone is utilized to further crack the feed to produce motor fuel.
    Type: Grant
    Filed: October 24, 1997
    Date of Patent: November 16, 1999
    Assignee: UOP LLC
    Inventors: Richard K. Hoehn, Vasant P. Thakkar
  • Patent number: 5980729
    Abstract: A hydrocracking process wherein a hydrocarbonaceous feedstock and a hot hydrocracking zone effluent containing hydrogen is passed to a denitrification and desulfurization reaction zone to produce hydrogen sulfide and ammonia to thereby clean up the fresh feedstock. The resulting hot, uncooled effluent from the denitrification and desulfurization zone is hydrogen stripped in a stripping zone maintained at essentially the same pressure as the preceding reaction zone with a hydrogen-rich gaseous stream to produce a vapor stream comprising hydrogen, hydrocarbonaceous compounds boiling at a temperature below the boiling range of the fresh feedstock, hydrogen sulfide and ammonia, and a liquid hydrocarbonaceous stream.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: November 9, 1999
    Assignee: UOP LLC
    Inventors: Tom N. Kalnes, Vasant P. Thakkar
  • Patent number: 5904835
    Abstract: A large hydrocracking feed stream is processed without resorting to full dual reaction trains by passing a portion of the feed stream into each of two reaction zones, with the effluents of the two reaction zones being charged into a common separation and product recovery facility. Unconverted hydrocarbons recovered in the product recovery facility are passed into only one of the reaction zones.
    Type: Grant
    Filed: October 24, 1997
    Date of Patent: May 18, 1999
    Assignee: UOP LLC
    Inventor: Vasant P. Thakkar
  • Patent number: 5885440
    Abstract: The invention is a hydrocracking process which employs a small reactor-containing hydrotreating catalyst to reduce the recombinant mercaptan content and/or smoke point of a product recovered from the effluent of the hydrocracking reactor. The entire effluent of the hydrocracking reactor is first cooled by indirect heat exchange and then passed through the hydrotreating catalyst. The effluent of the hydrotreating catalyst then continues throughout the customary cooling and separation steps employed in the product recovery system.
    Type: Grant
    Filed: August 26, 1997
    Date of Patent: March 23, 1999
    Assignee: UOP LLC
    Inventors: Richard K. Hoehn, Vasant P. Thakkar, Daniel L. Ellig