Patents by Inventor Mahendra Sunkara

Mahendra Sunkara 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: 11591226
    Abstract: The present development is a process to produce commodity chemicals such as methanol and syngas using an integrated plasma catalysis technology. The method comprises providing a fixed or fluidized bed reactor having a microwave plasma flame and a catalyst bed with a catalyst, wherein the catalyst is an alloyed bimetallic nanowire. In the process, the plasma flame fluidizes the catalyst thereby producing a more effective catalyst than the non-fluidized catalyst. It is anticipated that the reactor can have a throughput capacity of up to 30 Lpm/kW and can be effective for the conversion of CO2, CH4, air, water, and combinations thereof, through reactions such as pure CO2 splitting, reverse water gas shift (RWGS) for CO production, methanol synthesis, and plasma reforming of methane, thereby making a system that would be attractive for small GTL units.
    Type: Grant
    Filed: August 24, 2021
    Date of Patent: February 28, 2023
    Assignee: Advanced Energy Materials, LLC
    Inventors: Mahendra Sunkara, Sivakumar Vasireddy, Vivekanand Kumar, Juan He, Tu Nguyen, Veerendra Atla
  • Publication number: 20220184580
    Abstract: The present invention is a method for removing sulfur from liquid hydrocarbon feedstocks and for performing hydrogenation reactions in sulfur-contaminated feedstocks, including the hydrogenation of naphthalene in the presence of sulfur compounds, using catalysts or adsorbents comprising metal oxide nanowires decorated with reduced catalytically-active metal particles. In a preferred embodiment, the adsorbent comprises zinc oxide nanowires decorated with catalytically-active metals selected from nickel, cobalt, molybdenum, platinum, palladium, copper, oxides thereof, alloys thereof, and combinations thereof. In some embodiments, the sulfur is removed through a desulfurization process without an external hydrogen supply. The process is effective for the removal of sulfur from diesel fuels and liquid fuel streams, and for deep desulfurization of natural gas streams. The process is also effective for the selective hydrogenation of naphthalene to tetralin in the presence of sulfur compounds.
    Type: Application
    Filed: February 18, 2022
    Publication date: June 16, 2022
    Inventors: Mahendra Sunkara, Sivakumar Vasireddy, Juan He
  • Patent number: 11306065
    Abstract: The present development is a method for the selective conversion of furfural to 2-methylfuran (2-MF) using a catalyst comprising non-toxic and non-noble metals and wherein the method requires relatively mild processing conditions. The catalyst comprises copper metal particles, used alone or in combination with cobalt, nickel, manganese, ruthenium, gallium, zinc, aluminum or a combination thereof, on a nanowire support. The catalyst is stable in liquid phase reactions and in the presence of water. The present development also includes a process for producing the catalyst.
    Type: Grant
    Filed: December 4, 2019
    Date of Patent: April 19, 2022
    Inventors: Mahendra Sunkara, Sivakumar Vasireddy, Juan He, Hugo Apolo Nambo Salgado
  • Patent number: 11305229
    Abstract: The present development is a method for capturing and purifying CO2 from a flue gas stream using a metal aluminate nanowire absorbent and then regenerating the absorbent. After the CO2 is adsorbed into the absorbent, the adsorbent is regenerated by subjecting the CO2 saturated adsorbent to a dielectric barrier discharge plasma or to a microwave plasma or to a radio frequency (RF) plasma while ensuring that the external temperature does not exceed 200° C.
    Type: Grant
    Filed: December 31, 2020
    Date of Patent: April 19, 2022
    Inventors: Juan He, Tu Nguyen, Mahendra Sunkara
  • Patent number: 11254880
    Abstract: The present invention relates to the use of adsorbents comprising zinc oxide nanowires decorated with catalytically active metal particles for the removal of sulfur from hydrocarbon feedstocks, including the desulfurization of diesel fuels and the deep desulfurization of natural gas, and to the use of decorated zinc oxide nanowire adsorbents for the hydrogenation of naphthalene selectively to tetralin in the presence of sulfur compounds. The adsorbent comprises nickel metal particles or nickel-zinc alloy particles deposited on zinc oxide nanowires.
    Type: Grant
    Filed: April 6, 2020
    Date of Patent: February 22, 2022
    Assignee: Advanced Energy Materials, LLC
    Inventors: Mahendra Sunkara, Sivakumar Vasireddy, Juan He
  • Patent number: 11103848
    Abstract: The present development is a reactor system for the production of nanostructures. The reactor system comprises a conical reactor body designed to maintain an upwardly directed vertical plasma flame and hydrocarbon flame. The reactor system further includes a metal powder feed that feeds into the plasma flame, a cyclone and a dust removal unit. The system is designed to produce up to 100 grams of metal oxide nanomaterials per minute.
    Type: Grant
    Filed: August 15, 2017
    Date of Patent: August 31, 2021
    Assignee: Advanced Energy Materials, LLC
    Inventors: Mahendra Sunkara, Tu Quang Nguyen, Lukus Guhy, William Paxton
  • Patent number: 10766787
    Abstract: A method for the rapid and controlled synthesis of mixed metal oxide nanoparticles using relatively low temperature plasma oxidation of liquid droplets of predetermined mixed metal precursors is disclosed. The resulting nanoparticles reflect the metal precursor stoichiometries and the mixed metal oxide's metastable phase can be controlled. The synthesis of mixed transition metal oxide comprising binary metal oxides, ternary mixed metal oxides, quaternary mixed metal oxides and pentanary mixed metal oxides are demonstrated herein.
    Type: Grant
    Filed: November 2, 2016
    Date of Patent: September 8, 2020
    Assignee: University of Louisville Research Foundation, Inc.
    Inventors: Mahendra Sunkara, Babajide Patrick Ajayi, Daniel F. Jaramillo-Cabanzo, Hugo Apolo Nambo Salgado
  • Publication number: 20200231882
    Abstract: The present invention relates to the use of adsorbents comprising zinc oxide nanowires decorated with catalytically active metal particles for the removal of sulfur from hydrocarbon feedstocks, including the desulfurization of diesel fuels and the deep desulfurization of natural gas, and to the use of decorated zinc oxide nanowire adsorbents for the hydrogenation of naphthalene selectively to tetralin in the presence of sulfur compounds. The adsorbent comprises nickel metal particles or nickel-zinc alloy particles deposited on zinc oxide nanowires.
    Type: Application
    Filed: April 6, 2020
    Publication date: July 23, 2020
    Inventors: Mahendra Sunkara, Sivakumar Vasireddy, Juan He
  • Publication number: 20200188873
    Abstract: The present development is a new approach for deep desulfurization by adsorption of for removing sulfur using a solid adsorbent under atmospheric pressure and elevated temperatures from liquid fuels such as diesel, waste lube oil without using hydrogen. The adsorbent comprises metal particles from a group of Ni, Pt, Co, Mo and Cu deposited on MOx nanowires (M=Zn, Fe and Mn).
    Type: Application
    Filed: February 8, 2018
    Publication date: June 18, 2020
    Inventors: Mahendra Sunkara, Sivakumar Vasireddy, Juan He
  • Publication number: 20190193044
    Abstract: The present development is a reactor system for the production of nanostructures. The reactor system comprises a conical reactor body designed to maintain an upwardly directed vertical plasma flame and hydrocarbon flame. The reactor system further includes a metal powder feed that feeds into the plasma flame, a cyclone and a dust removal unit. The system is designed to produce up to 100 grams of metal oxide nanomaterials per minute.
    Type: Application
    Filed: August 15, 2017
    Publication date: June 27, 2019
    Applicant: Advanced Energy Materials, LLC
    Inventors: Mahendra Sunkara, Tu Quang Nguyen, Lukus Guhy, William Paxton
  • Patent number: 10030201
    Abstract: The present development is a catalyst composition, comprising zinc oxide nanowires having one or more catalytically-active metal particles attached to a surface of the zinc oxide nanowires. The catalytically-active metal particles are comprised of a metal selected from the group consisting of nickel, cobalt, molybdenum, tungsten, copper, and platinum. The present development further discloses a method to prepare the catalyst composition, and use of the catalyst composition for desulfurization.
    Type: Grant
    Filed: July 15, 2013
    Date of Patent: July 24, 2018
    Assignee: University of Louisville Research Foundation
    Inventors: Mahendra Sunkara, Franz Petzold, Mayank Gupta, Dania Alvarez Fonseca
  • Publication number: 20070209576
    Abstract: A method of producing networks of low melting metal oxides such as crystalline gallium oxide comprised of one-dimensional nanostructures. Because of the unique arrangement of wires, these crystalline networks defined as “nanowebs”, “nanowire networks”, and/or “two-dimensional nanowires”. Nanowebs contain wire densities on the order of 109/cm2. A possible mechanism for the fast self-assembly of crystalline metal oxide nanowires involves multiple nucleation and coalescence via oxidation-reduction reactions at the molecular level. The preferential growth of nanowires parallel to the substrate enables them to coalesce into regular polygonal networks. The individual segments of the polygonal network consist of both nanowires and nanotubules of ?-gallium oxide. The synthesis of highly crystalline noncatalytic low melting metals such as ?-gallium oxide tubes, nanowires, and nanopaintbrushes is accomplished using molten gallium and microwave plasma containing a mixture of monoatomic oxygen and hydrogen.
    Type: Application
    Filed: June 16, 2004
    Publication date: September 13, 2007
    Inventors: Mahendra Sunkara, Shashank Sharma, Burtron Davis, Uschi Graham
  • Publication number: 20070118938
    Abstract: A process for the rapid synthesis of metal oxide nanoparticles at low temperatures and methods which facilitate the fabrication of long metal oxide nanowires. The method is based on treatment of metals with oxygen plasma. Using oxygen plasma at low temperatures allows for rapid growth unlike other synthesis methods where nanomaterials take a long time to grow. Density of neutral oxygen atoms in plasma is a controlling factor for the yield of nanowires. The oxygen atom density window differs for different materials. By selecting the optimal oxygen atom density for various materials the yield can be maximized for nanowire synthesis of the metal.
    Type: Application
    Filed: March 20, 2006
    Publication date: May 24, 2007
    Inventors: Mahendra Sunkara, Sreeram Vaddiraju, Miran Mozetic, Uros Cvelbar
  • Publication number: 20070095276
    Abstract: A process is provided to produce bulk quantities of nanowires in a variety of semiconductor materials. Thin films and droplets of low-melting metals such as gallium, indium, bismuth, and aluminum are used to dissolve and to produce nanowires. The dissolution of solutes can be achieved by using a solid source of solute and low-melting metal, or using a vapor phase source of solute and low-melting metal. The resulting nanowires range in size from 1 nanometer up to 1 micron in diameter and lengths ranging from 1 nanometer to several hundred nanometers or microns. This process does not require the use of metals such as gold and iron in the form of clusters whose size determines the resulting nanowire size. In addition, the process allows for a lower growth temperature, better control over size and size distribution, and better control over the composition and purity of the nanowire produced therefrom.
    Type: Application
    Filed: September 14, 2006
    Publication date: May 3, 2007
    Inventors: Mahendra Sunkara, Shashank Sharma, Hari Chandrasekaran, Hongwei Li, Sreeram Vaddiraju
  • Publication number: 20070087470
    Abstract: Vapor phase methods for synthesizing metal nanowires directly without the help of templates. A vapor phase method in which nucleation and growth of metal oxides at temperatures higher than the oxide decomposition temperatures lead to the respective metal nanowires. The chemical vapor transport of tungsten in the presence of oxygen onto substrates kept at temperatures higher than the tungsten oxide decomposition temperature (˜1450° C.) led to nucleation and growth of pure metallic tungsten nanowires. In a similar procedure, tungsten oxide nanowires were synthesized by maintaining the substrates at a temperature lower than the decomposition temperature of tungsten oxide. The vapor transport of low-melting metal oxides provides a procedure for synthesizing metal and metal oxide nanowires.
    Type: Application
    Filed: September 29, 2006
    Publication date: April 19, 2007
    Inventors: Mahendra Sunkara, Sreeram Vaddiraju, Biswapriya Deb, Jyothish Thangala
  • Publication number: 20070003467
    Abstract: This invention presents a process to produce bulk quantities of nanowires of a variety of semiconductor materials. Large liquid gallium drops are used as sinks for the gas phase solute, generated in-situ facilitated by microwave plasma. To grow silicon nanowires for example, a silicon substrate covered with gallium droplets is exposed to a microwave plasma containing atomic hydrogen. A range of process parameters such as microwave power, pressure, inlet gas phase composition, were used to synthesize silicon nanowires as small as 4 nm (nanometers) in diameter and several micrometers long. As opposed to the present technology, the instant technique does not require creation of quantum sized liquid metal droplets to synthesize nanowires. In addition, it offers advantages such as lower growth temperature, better control over size and size distribution, better control over the composition and purity of the nanowires.
    Type: Application
    Filed: September 1, 2006
    Publication date: January 4, 2007
    Inventors: Mahendra Sunkara, Shashank Sharma
  • Publication number: 20060065989
    Abstract: Described herein are methods and systems for forming lenses. In one embodiment, systems for use in forming eyeglass lenses are described that include one or more LED lights. The LED lights may be used to cure lens forming compositions and coating compositions. In other embodiments, methods of determining an appropriate spacing for mold members are described. In other embodiments, methods of forming anti-reflective coatings, photochromic coatings, hardcoat coatings, and combinations thereof, on eyeglass lenses, are described.
    Type: Application
    Filed: August 12, 2005
    Publication date: March 30, 2006
    Inventors: Thad Druffel, Xiaodong Sun, Kevin Krogman, Mahendra Sunkara, Matthew Lattis, John Foreman, Omar Buazza, Loren Lossman, Galen Powers
  • Publication number: 20050260119
    Abstract: A new morphological manifestation of carbon based nanostructures in the form of tapered whiskers with uniform 1-3 nm hollowness. The base of the whiskers is in the sub-micron scale, tapering uniformly to form a pointed tip in the form of a pipette. The hollow nanopipettes have a shell containing helical graphitic sheets.
    Type: Application
    Filed: September 9, 2004
    Publication date: November 24, 2005
    Inventors: Mahendra Sunkara, Radhika Mani
  • Publication number: 20050238567
    Abstract: A method of synthesizing and controlling the internal diameters, conical angles, and morphology of tubular carbon nano/micro structures. Different morphologies can be synthesized included but not limited to cones, straight tubes, nozzles, cone-on-tube (funnels), tube-on-cone, cone-tube-cone, n-staged structures, multijunctioned tubes, Y-junctions, dumbbell (pinched morphology) and capsules. The process is based on changing the wetting behavior of a low melting metals such as gallium, indium, and aluminum with carbon using a growth environment of different gas phase chemistries. The described carbon tubular morphologies can be synthesized using any kind of gas phase excitation such as, but not limited to, microwave excitation, hot filament excitation, thermal excitation and Radio Frequency (RF) excitations. The depositions area is only limited by the substrate area in the equipment used and not limited by the process.
    Type: Application
    Filed: September 9, 2004
    Publication date: October 27, 2005
    Inventors: Mahendra Sunkara, Gopinath Bhimarasetti
  • Publication number: 20050072351
    Abstract: The bulk synthesis of highly crystalline noncatalytic low melting metals such as ?-gallium oxide tubes, nanowires, and nanopaintbrushes is accomplished using molten gallium and microwave plasma containing a mixture of monoatomic oxygen and hydrogen. Gallium oxide nanowires were 20-100 nm thick and tens to hundreds of microns long. Transmission electron microscopy (TEM) revealed the nanowires to be highly crystalline and devoid of any structural defects. Results showed that multiple nucleation and growth of gallium oxide nanostructures can occur directly out of molten gallium exposed to appropriate composition of hydrogen and oxygen in the gas phase. These gallium oxide nanostructures are of particular interest for opto-electronic devices and catalytic applications.
    Type: Application
    Filed: September 16, 2003
    Publication date: April 7, 2005
    Inventors: Mahendra Sunkara, Shashank Sharma