Patents by Inventor Subhas Sikdar

Subhas Sikdar 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: 8888994
    Abstract: Method for deep desulphurization of hydrocarbon fuels includes following steps: (1) treatment of a hydrocarbon fuel under the condition of its mixing with gaseous oxidant selected from the group consisting nitrogen monoxide, dry air, ozone and a mixture of at least two of said reagents in order to oxidize sulfur-containing compounds presented in said fuel, and with a fine-dispersed adsorbent based on montmorillonite in order to adsorb oxidized sulfur-containing compounds, and (2) separation of spent adsorbent together with adsorbed oxidized sulfur-containing compounds from refined fuel.
    Type: Grant
    Filed: April 19, 2011
    Date of Patent: November 18, 2014
    Assignee: The United States of America as represented by the Administrator of the U.S. Environmental Protection Agency
    Inventors: Valerii Kukhar, Volodymir Kashkovski, Vladislav Kyselov, Yurii Besugly, Yurii Kyselov, Rajender Varma, Subhas Sikdar
  • Publication number: 20110259797
    Abstract: Method for deep desulphurization of hydrocarbon fuels includes following steps: (1) treatment of a hydrocarbon fuel under the condition of its mixing with gaseous oxidant selected from the group consisting nitrogen monoxide, dry air, ozone and a mixture of at least two of said reagents in order to oxidize sulfur-containing compounds presented in said fuel, and with a fine-dispersed adsorbent based on montmorillonite in order to adsorb oxidized sulfur-containing compounds, and (2) separation of spent adsorbent together with adsorbed oxidized sulfur-containing compounds from refined fuel.
    Type: Application
    Filed: April 19, 2011
    Publication date: October 27, 2011
    Inventors: Valerii Kukhar, Volodymir Kashkovski, Vladislav Kyselov, Yurii Besugly, Yurii Kyselov, Rajender S. Varma, Subhas Sikdar
  • Patent number: 8029662
    Abstract: The disclosed sorbents are for adsorbing sulfur compounds, particularly sulfur-containing aromatic compounds, from liquid hydrocarbon fuels such as gasoline, cracked gasoline, diesel, high sulfur liquid fossil fuels, ultra-low sulfur fuel (ULSF) in fuel cell applications, and mixtures thereof. The sorbent compositions comprise one or more silicates having one or more metal nitrates admixed together. The one or more metal nitrates include iron (II) or (III), zinc (II), cadmium (II) and mercury (II) nitrate. The method of preparing and using the sorbents is also provided.
    Type: Grant
    Filed: June 6, 2008
    Date of Patent: October 4, 2011
    Assignee: The United States of America as represented by the Administrator of the Environmental Protection Agency
    Inventors: Rajender S. Varma, Yuhong Ju, Subhas Sikdar
  • Patent number: 7858061
    Abstract: Oxidative sorbents are provided for adsorbing elemental or oxidized mercury from mercury-containing fluids such as flue gas from a coal-burning power utility or the like at a temperature range of about 50 to 350° C. The method of preparing and using the oxidative sorbents is also provided. The oxidative sorbent compositions include one or more silicates capable of cation exchange with a plurality of active metal cations and their counter anions. The silicates may include those selected from clays such as montmorillonite, laumonite, bentonite, Mica, vermiculite and kaolinite, and from silica gels, natural and synthetic molecular sieves, zeolites, and ashes from stoker- and pulverized coal-fired boilers. The one or more oxidative metal halides and/or sulfates may be selected from the group consisting of CuCl, CuBr, CuCl2, CuBr2, CuSO4, FeCl2, FeCl3, FeSO4, Fe2(SO4)3, ZnCl2, ZnBr2, NiCl2, and NiSO4. The oxidative sorbents may also include activated carbon.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: December 28, 2010
    Assignee: The United States of America as represented by the Administrator of the United States Environmental Protection Agency
    Inventors: Rajender S. Varma, Yuhong Ju, Subhas Sikdar, Joo Youp Lee, Timothy C. Keener
  • Publication number: 20080257785
    Abstract: The disclosed sorbents are for adsorbing sulfur compounds, particularly sulfur-containing aromatic compounds, from liquid hydrocarbon fuels such as gasoline, cracked gasoline, diesel, high sulfur liquid fossil fuels, ultra-low sulfur fuel (ULSF) in fuel cell applications, and mixtures thereof. The sorbent compositions comprise one or more silicates having one or more metal nitrates admixed together. The one or more metal nitrates include iron (II) or (III), zinc (II), cadmium (II) and mercury (II) nitrate. The method of preparing and using the sorbents is also provided.
    Type: Application
    Filed: June 6, 2008
    Publication date: October 23, 2008
    Inventors: Rajender S. Varma, Yuhong Ju, Subhas Sikdar
  • Publication number: 20070140940
    Abstract: Oxidative sorbents are provided for adsorbing elemental or oxidized mercury from mercury-containing fluids such as flue gas from a coal-burning power utility or the like at a temperature range of about 50 to 350 ° C. The method of preparing and using the oxidative sorbents is also provided. The oxidative sorbent compositions include one or more silicates capable of cation exchange with a plurality of active metal cations and their counter anions. The silicates may include those selected from clays such as montmorillonite, laumonite, bentonite, Mica, vermiculite and kaolinite, and from silica gels, natural and synthetic molecular sieves, zeolites, and ashes from stoker- and pulverized coal-fired boilers. The one or more oxidative metal halides and/or sulfates may be selected from the group consisting of CuCl, CuBr, CuCl2, CuBr2, CuSO4, FeCl2, FeCl3, FeSO4, Fe2(SO4)3, ZnCl2, ZnBr2, NiCl2, and NiSO4. The oxidative sorbents may also include activated carbon.
    Type: Application
    Filed: December 15, 2005
    Publication date: June 21, 2007
    Inventors: Rajender Varma, Yuhong Ju, Subhas Sikdar, Joo Lee, Timothy Keener
  • Publication number: 20070138062
    Abstract: The disclosed sorbents are for adsorbing sulfur compounds, particularly sulfur-containing aromatic compounds, from liquid hydrocarbon fuels such as gasoline, cracked gasoline, diesel, high sulfur liquid fossil fuels, ultra-low sulfur fuel (ULSF) in fuel cell applications, and mixtures thereof. The sorbent compositions comprise one or more silicates having one or more metal nitrates admixed together. The one or more metal nitrates include iron (II) or (III), zinc (II), cadmium (II) and mercury (II) nitrate. The method of preparing and using the sorbents is also provided.
    Type: Application
    Filed: December 15, 2005
    Publication date: June 21, 2007
    Inventors: Rajender Varma, Yuhong Ju, Subhas Sikdar
  • Patent number: 6039878
    Abstract: Volatile organic compounds (VOCS) can be removed from surfactant solutions using pervaporation with hydrophobic pervaporation membranes. This process can be used to remove volatile non-laqueous phase liquids from surfactant-based soil washing and soil flushing solutions for recovery of the volatile compounds and reuse of the surfactant. The process of the present invention can also be used to separate VOCs from industrial process streams containing surfactants for in-process recycling and reclamation of the VOCs and/or surfactants. In addition, the process of the present invention can be used to separate VOCs from industrial waste streams containing surfactants for waste volume reduction or for recovery/recycle of the VOCs and/or surfactant.
    Type: Grant
    Filed: May 23, 1997
    Date of Patent: March 21, 2000
    Assignee: The United States of America as represented by the United States Environmental Protection Agency
    Inventors: Subhas Sikdar, Leland Vane