Patents by Inventor Rafael L. Espinoza

Rafael L. Espinoza 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: 7135152
    Abstract: A gas-agitated multiphase reactor system with multiple reaction zones comprising gas-liquid or gas-liquid-solid mixtures that can maximize the production rate while allowing better control of the temperature distribution and better control of the liquid and solid phases in the reactors.
    Type: Grant
    Filed: May 10, 2004
    Date of Patent: November 14, 2006
    Assignee: ConocoPhillips Company
    Inventors: Rafael L. Espinoza, Jianping Zhang, Sergio R. Mohedas, James D. Ortega, Jr.
  • Patent number: 7078439
    Abstract: This invention relates to methods and apparatus for separating liquid products and catalyst particles from a slurry used in a Fischer-Tropsch reactor system. The preferred embodiments of the present invention are characterized by a separation system that uses a sedimentation chamber, which contains at least one inclined channel that enhances the settling of particles within the slurry. The enhanced settling separates the slurry into a catalyst-rich bottom stream and a catalyst-lean overhead stream. The catalyst-rich bottom product stream is preferably recycled to the reactor, while the catalyst-lean overhead stream can be further processed by a secondary separation system to produce valuable synthetic fuels. The inclined channel may be provided by a structure selected from the group consisting of tube, pipe, conduit, sheets, trays, walls, plates, and combinations thereof.
    Type: Grant
    Filed: January 7, 2004
    Date of Patent: July 18, 2006
    Assignee: ConocoPhillips Company
    Inventors: Oluwaseyi A. Odueyungbo, Rafael L. Espinoza, Sergio R. Mohedas, James Dale Ortego, Jr., Beatrice C. Ortego, Ralph T. Goodwin, Todd H. Harkins
  • Patent number: 7071239
    Abstract: A catalyst and method for producing hydrocarbons using a catalyst support having an improved hydrothermal stability, such as under Fischer-Tropsch synthesis conditions. The stabilized support is made by a method comprising treating a boehmite material in contact with at least one structural stabilizer. Contacting the boehmite with at least one structural stabilizer can include forming a mixture comprising the boehmite material and at the least one structural stabilizer. The mixture can be a sol or a slurry. The treating preferably includes drying or spray drying the mixture, and calcining in an oxidizing atmosphere to obtain the stabilized support. Preferred structural stabilizers can include an element, such as cobalt, magnesium, zirconium, boron, aluminum, barium, silicon, lanthanum, oxides thereof, or combinations thereof; or can include precipitated oxides, such as a co-precipitated silica-alumina.
    Type: Grant
    Filed: October 16, 2003
    Date of Patent: July 4, 2006
    Assignee: ConocoPhillips Company
    Inventors: J. Dale Ortego, Jr., Kandaswamy Jothimurugesan, Rafael L. Espinoza, Kevin L. Coy, Beatrice C. Ortego
  • Patent number: 7067562
    Abstract: The present invention presents an iron-based Fischer-Tropsch catalyst having a low water-gas shift activity and high selectivity and productivity toward a hydrocarbon wax wherein said catalyst comprises iron; silver; sodium, lithium, potassium, rubidium and/or cesium; optionally, calcium, magnesium, boron, and/or aluminum; and a silica structural promoter. The present invention further presents a method of making a precipitated iron-based Fischer-Tropsch catalyst. The present invention still further presents a process for producing hydrocarbons using the iron-based, precipitated Fischer-Tropsch catalyst of the present invention.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: June 27, 2006
    Assignee: ConocoPhillips Company
    Inventors: Rafael L. Espinoza, Kandaswamy Jothimurugesan, Ajoy P. Raje
  • Patent number: 7056955
    Abstract: According to a preferred embodiment, the present invention features a bulk catalyst that includes precipitated cobalt metal. The precipitated cobalt catalyst further includes a textural promoter, a binder and optionally a Group I metal. The method of making the catalyst is optimized so as to enhance attrition resistance and improve activity. According to some embodiments, the present catalyst is made by a method that includes one or a combination of: calcination under optimized temperature conditions; exposure to an acidic solution; and addition of a binder to a suspension of a precipitate. According to some embodiments, a Fischer-Tropsch process includes contacting the present catalyst with a feed stream containing carbon monoxide and hydrogen so as to produce hydrocarbons.
    Type: Grant
    Filed: December 22, 2003
    Date of Patent: June 6, 2006
    Assignee: ConocoPhillips Company
    Inventors: Rafael L. Espinoza, Kandaswamy Jothimurugesan, Ajoy P. Raje, Kevin L. Coy, Nithya Srinivasan
  • Patent number: 7056857
    Abstract: A method for making a catalyst is provided that features loading a catalytic metal to a support using at least two different precursor compounds of that said metal; and loading the promoter to the support in an amount effective so as to achieve similar promotion as for a comparable catalyst comprising a greater amount of the promoter using only one precursor compound, where the catalytic metal is selected from among Group 8 metals, 9 metal, Group 10 metals, and combinations thereof. The promoter is preferably boron, silver, a noble metal, or combination thereof. Also provided are catalysts made by the method and Fischer-Tropsch processes that include contacting synthesis gas with a catalyst made by the method.
    Type: Grant
    Filed: October 14, 2004
    Date of Patent: June 6, 2006
    Assignee: ConocoPhillips Company
    Inventors: Nithya Srinivasan, Rafael L. Espinoza, Kevin L. Coy, Kandaswamy Jothimurugesan
  • Patent number: 7022741
    Abstract: The present invention provides an apparatus and method for optimizing the degree of backmixing within a gas agitated multiphase reactor at a given gas linear velocity. The embodiments of the present invention involve novel configurations of the multiphase reactor internal structures. In general, the configurations comprise creating a dense area of internal structures in the central region and/or wall regions of the multiphase reactor.
    Type: Grant
    Filed: March 28, 2003
    Date of Patent: April 4, 2006
    Assignee: ConocoPhillips Company
    Inventors: Yi Jiang, Jianping Zhang, Rafael L. Espinoza, Harold A. Wright
  • Patent number: 7019038
    Abstract: Methods for reducing the average molecular weight of liquid hydrocarbons in a Fischer-Tropsch reactor are disclosed. The preferred embodiments of the present invention are characterized by feeding a hydrocarbon stream, which lowers the average molecular weight of the hydrocarbon liquids inside the reactor, and more preferably by recycling a portion of low-molecular weight hydrocarbon products back into the reactor. Lowering the molecular weight of the hydrocarbon liquids inside the reactor increases the mass transfer and solubility, and diffusivity of the reactants in the hydrocarbons present in the slurry.
    Type: Grant
    Filed: May 23, 2003
    Date of Patent: March 28, 2006
    Assignee: ConocoPhillips Company
    Inventors: Rafael L. Espinoza, Harold A. Wright, Jianping Zhang
  • Patent number: 7012104
    Abstract: A hydrothermally-stable catalyst, method for making the same, and process for producing hydrocarbon, wherein the catalyst is used in synthesis gas conversion to hydrocarbons. In one embodiment, the method comprises depositing a compound of a catalytic metal selected from Groups 8, 9, and 10 of the Periodic Table on a support material comprising boehmite to form a composite material; and calcining the composite material to form the catalyst. In other embodiments, the support material comprises synthetic boehmite, natural boehmite, pseudo-boehmite, or combinations thereof.
    Type: Grant
    Filed: October 16, 2003
    Date of Patent: March 14, 2006
    Assignee: ConocoPhillips Company
    Inventors: Rafael L. Espinoza, Yaming Jin, Kandaswamy Jothimurugesan, Nithya Srinivasan
  • Patent number: 7012103
    Abstract: A process for producing hydrocarbons comprises providing a multi-tubular reactor having at least 100 tubes units containing a catalyst, each tube being between 2 and 5 meters tall and in thermal contact with a cooling fluid; feeding hydrogen and carbon monoxide to each tube at a linear gas superficial velocity less than about 60 cm/s; and converting the gas feedstream to hydrocarbons on the catalyst, wherein the yield of hydrocarbons in each tube is greater than 100 (kg hydrocarbons)/hr/(m3 reaction zone). Each tube may have an internal diameter greater than 2 centimeters. The catalyst may be active for Fischer Tropsch synthesis and may comprise cobalt or iron. The maximum difference in the radially-averaged temperature between two points that are axially spaced along the reactor is less than 15° C., preferably less than 10° C. The catalyst loading or intrinsic activity may vary along the length of the reactor.
    Type: Grant
    Filed: March 24, 2003
    Date of Patent: March 14, 2006
    Assignee: ConocoPhillips Company
    Inventors: Rafael L. Espinoza, Jianping Zhang, Harold A. Wright, Todd H. Harkins
  • Patent number: 6962947
    Abstract: A process is disclosed for regenerating a catalyst used in a process for synthesizing hydrocarbons. The synthesis process involves contacting a feed stream comprising hydrogen and carbon monoxide with a catalyst in a reaction zone maintained at conversion-promoting conditions effective to produce an effluent stream comprising hydrocarbons. The regeneration process involves contacting a deactivated Fischer-Tropsch catalyst with a regeneration gas under regeneration-promoting conditions that include a pressure lower than the mean Fischer-Tropsch reaction pressure, for a period of time sufficient to reactivate the Fischer-Tropsch catalyst.
    Type: Grant
    Filed: January 13, 2005
    Date of Patent: November 8, 2005
    Assignee: ConocoPhillips Company
    Inventors: Harold A. Wright, Ajoy P. Raje, Rafael L. Espinoza
  • Patent number: 6958363
    Abstract: The present invention provides a process for managing hydrogen in a hydrocarbon gas to liquid plant. The process includes passing a syngas feed stream produced by a partial oxidation reactor to a Fischer-Tropsch reactor, thereby converting the syngas to hydrocarbon liquids. The hydrogen management process further includes passing a second hydrogen rich stream produced by an auxiliary source to a hydrogen user such as an FT water stripper, an FT catalyst regeneration unit, and an FT product upgrading unit. The auxiliary source could be a process for converting hydrocarbons to syngas, a process for converting hydrocarbons to olefins, a process for converting hydrocarbons to aromatics, a process for catalytically dehydrogenating hydrocarbons, a process for catalytically cracking hydrocarbons, a process for refining petroleum, and a process for converting hydrocarbons to carbon filaments.
    Type: Grant
    Filed: March 15, 2003
    Date of Patent: October 25, 2005
    Assignee: ConocoPhillips Company
    Inventors: Rafael L. Espinoza, Sergio R. Mohedas, Ralph T. Goodwin, III, Stephen R. Landis, Barbara A. Belt
  • Patent number: 6956063
    Abstract: The present invention relates to a method and apparatus for water removal in multi-phase reactors operating at Fischer-Tropsch conditions. In a preferred embodiment of the present invention, a method of reducing the concentration of water in a multi-phase reactor for Fisher-Tropsch synthesis containing an expanded slurry bed and a water-rich slurry region includes removing a portion of water from the water-rich slurry from a predetermined region in the reactor, removing the water from the water-rich slurry to form a water-reduced slurry, and returning the water-reduced slurry back to the reactor. Preferably the water-rich slurry region is located between ½ H to H and ½ R to R, where H is the height of the expanded slurry bed and R is the radius of the expanded slurry bed.
    Type: Grant
    Filed: December 10, 2002
    Date of Patent: October 18, 2005
    Assignee: ConocoPhillips Company
    Inventors: Jianping Zhang, Rafael L. Espinoza
  • Patent number: 6946493
    Abstract: The present invention provides a process for managing hydrogen in a hydrocarbon gas to liquid plant. The process includes feeding a syngas stream produced by a partial oxidation reactor to a Fischer-Tropsch reactor, thereby converting the syngas to hydrocarbon liquids. It also includes passing a substantially oxygen-free feed stream comprising hydrocarbon gas and water to a steam reformer, thereby producing a hydrogen-rich stream. The H2/CO ratio in the syngas feed stream can be adjusted to a desired value by introducing a first portion of the hydrogen-rich stream to the syngas feed stream. A second portion of the hydrogen-rich stream can be passed to one or more hydrogen users, e.g., a catalyst regeneration unit, in the GTL plant.
    Type: Grant
    Filed: March 15, 2003
    Date of Patent: September 20, 2005
    Assignee: ConocoPhillips Company
    Inventors: Sergio R. Mohedas, Stephen R. Landis, Rafael L. Espinoza, Ralph T. Goodwin, III, Barbara A. Belt
  • Patent number: 6929754
    Abstract: Methods and apparatus for removing wax products from a slurry used in a Fischer-Tropsch reactor. The preferred embodiments of the present invention are characterized by a solid/liquid separation system that removes liquid products from a slurry by drawing the fluid across a filter medium composed of a filter cake disposed on a substrate. In the preferred embodiments, the filter cake is desirable and performs the majority of the filtration. In certain embodiments, the filter medium is disposed in a filter housing where slurry flows parallel to the longitudinal axis of the filter medium from and inlet to an outlet. The characteristics or properties of the cake, which will effect the performance of the solid/liquid separation system, can be controlled by regulating the velocity of the slurry flowing across the cake, where the velocity may be regulated by adjusting the slurry flow through the filter housing or may be self-regulated by changing slurry velocities influenced by the design of the filter housing.
    Type: Grant
    Filed: April 16, 2003
    Date of Patent: August 16, 2005
    Assignee: ConocoPhillips Company
    Inventors: Rafael L. Espinoza, Sergio R. Mohedas, Doug S. Jack, Oluwaseyi A. Odueyungbo, James Dale Ortego, Jr.
  • Patent number: 6914082
    Abstract: A gas-agitated multiphase reactor system for the synthesis of hydrocarbons gives high catalyst productivity and reactor capacity. The system includes operating a multi-phase reactor in the well-mixed gas flow regime, with a Peclet number less than 0.175 and a single pass conversion ranging from 35% to 75%, wherein the inlet superficial gas velocity decreases with the decreasing of the reactor aspect ratio, and is preferably at least 20 cm/sec.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: July 5, 2005
    Assignee: ConocoPhillips Company
    Inventors: Jianping Zhang, Rafael L. Espinoza, Sergio Mohedas
  • Patent number: 6897246
    Abstract: A process for reducing C2-C9 olefin formation by recycling them to a Fischer-Tropsch hydrocarbon synthesis process and promoting recycled olefins chain growth comprises contacting a gas feed comprising a mixture of H2 and CO with a catalyst in a reactor system at conditions effective to produce a hydrocarbon product stream including C2-C9 olefins, separating a C2-C9 olefins-rich stream from the hydrocarbon product stream to form a light olefin recycle stream and recycling the light olefin recycle stream to the reactor system at a point in the reactor system where the H2:CO ratio is low relative to the H2:CO ratio in the rest of the reactor system. Depending on whether the initial H2:CO ratio is greater or less than the usage ratio of the selected catalyst, the recycled olefins can be returned to the system up- or downstream of the reactor system.
    Type: Grant
    Filed: November 12, 2002
    Date of Patent: May 24, 2005
    Assignee: ConocoPhillips Company
    Inventors: Rafael L. Espinoza, Ajoy P. Raje, Doug S. Jack
  • Patent number: 6887390
    Abstract: Methods for producing clean liquid/wax products from a slurry used in a Fischer-Tropsch reactor are disclosed. In general, one embodiment of the present invention comprises a solid/liquid filtration system having a filter medium comprising a substrate and a filter cake deposited on the substrate, wherein the filter cake is generated by deposition of solids from the slurry. The thickness of the filter cake can be maintained within a desired range by controlling the slurry velocity and/or the pressure differential across the filter medium. This invention relates to a method of operation of such filtration system which increases filtration cycle time and improved filtrate quality resulting in very low solid content in filtrate.
    Type: Grant
    Filed: April 16, 2003
    Date of Patent: May 3, 2005
    Assignee: ConocoPhillips Company
    Inventors: Sergio R. Mohedas, Rafael L. Espinoza, Doug S. Jack, Oluwasei A. Odueyungbo, James Dale Ortego, Jr.
  • Patent number: 6878655
    Abstract: The present invention is generally related towards the regeneration of hydrocarbon synthesis catalysts. In particular, the present invention is directed towards the regeneration of deactivated Fischer-Tropsch type catalysts using a two step process wherein the catalyst is first prepared using a dry gas and then regenerated using a hydrogen rich gas. The regeneration process is carried out at temperatures and pressures that are generally different than the operating temperatures and pressures for a typical hydrocarbon synthesis reaction.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: April 12, 2005
    Assignee: ConocoPhillips Company
    Inventors: Ajoy P. Raje, Rafael L. Espinoza, Jack E. Cnossen, Sergio R. Mohedas
  • Patent number: 6875339
    Abstract: The invention relates to methods for improving the octane number of a synthetic naphtha stream and optionally for producing olefins and/or solvents. In one embodiment, the method comprises aromatizing at least a portion of a synthetic naphtha stream to produce an aromatized hydrocarbon stream; and isomerizing at least a portion of the aromatized hydrocarbon stream to produce an isomerized aromatized hydrocarbon stream having a higher octane rating than the synthetic naphtha stream. Alternatively, the method comprises providing at least three synthetic naphtha cuts comprising a C4-C5 stream; a C6-C8 stream and a C9-C11 stream; aromatizing some of the C6-C8 stream to form an aromatized hydrocarbon stream with a higher octane number; steam cracking some of the C6-C8 stream and optionally the C9-C11 stream to form olefins; and selling some portions of C9-C11 stream as solvents. In preferred embodiments, the synthetic naphtha is derived from Fischer-Tropsch synthesis.
    Type: Grant
    Filed: March 8, 2004
    Date of Patent: April 5, 2005
    Assignee: ConocoPhillips Company
    Inventors: Priya Rangarajan, Steven R. McDonald, Joe D. Allison, Keith H. Lawson, Oluwaseyi A. Odueyungbo, Doug S. Jack, Rafael L. Espinoza