Patents by Inventor Nabil Rizkalla

Nabil Rizkalla 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: 7803957
    Abstract: A method for controlling ethylene oxidation uses ethylene and oxygen, in conjunction with a silver based catalyst, a moderator and a co-moderator, to form ethylene oxide. When controlling the ethylene oxidation reaction, the moderator concentration is maintained constant within a comparatively narrow operative concentration range and the co-moderator concentration is varied within a comparatively wider operative concentration range, to optimize a catalyst property such as the catalyst activity and/or the catalyst selectivity.
    Type: Grant
    Filed: September 11, 2007
    Date of Patent: September 28, 2010
    Assignee: SD Lizenzverwertungsgesellschaft mbH & Co. KG
    Inventors: Nabil Rizkalla, Howard Sachs, Mansoor Firoz Husain, Christian J. Gueckel, Andrzej Rokicki
  • Patent number: 7763096
    Abstract: The present invention relates to a method for recovering rhenium from an ethylene oxide catalyst containing rhenium and at least silver on a solid support, wherein at least a substantial portion of the rhenium present in the catalyst is extracted by intimate contact of the catalyst with one or more polar non-acidic organic solvents substantially free of water such that a rhenium-containing solution is formed containing the polar non-acidic organic solvent and extracted rhenium, the polar non-acidic organic solvent containing one or more oxygen, nitrogen, and/or halogen atoms in its molecular structure.
    Type: Grant
    Filed: May 6, 2008
    Date of Patent: July 27, 2010
    Assignee: SD Lizenzverwertungsgesellschaft mbH & Co. KG
    Inventors: Nabil Rizkalla, Andrzej Rokicki
  • Publication number: 20090277305
    Abstract: The present invention relates to a method for recovering rhenium from an ethylene oxide catalyst containing rhenium and at least silver on a solid support, wherein at least a substantial portion of the rhenium present in the catalyst is extracted by intimate contact of the catalyst with one or more polar non-acidic organic solvents substantially free of water such that a rhenium-containing solution is formed containing the polar non-acidic organic solvent and extracted rhenium, the polar non-acidic organic solvent containing one or more oxygen, nitrogen, and/or halogen atoms in its molecular structure.
    Type: Application
    Filed: May 6, 2008
    Publication date: November 12, 2009
    Applicant: SD LIZENZVERWERTUNGSGESELLSCHAFT MBH & CO. KG
    Inventors: Nabil Rizkalla, Andrzej Rokicki
  • Patent number: 7553980
    Abstract: A process for initiating a highly selective ethylene oxide catalyst is provided in which the highly selective ethylene oxide catalyst is operated first as a ‘standard’ Ag-based catalyst (e.g., a catalyst that contains only silver and alkali metal, especially cesium). Moreover, the inventive initiation procedure is more efficient when the concentration of carbon dioxide in the feed is higher than 6 vol. %, and even more efficient when the concentration of carbon dioxide in the feed is higher than 10 vol. %, of the feed mixture during the initiation period.
    Type: Grant
    Filed: September 26, 2007
    Date of Patent: June 30, 2009
    Assignee: SD Lizenzverwertungsgesellschaft mbH & Co. KG
    Inventors: Nabil Rizkalla, Barry Jay Billig, Norma B. Castagnola
  • Publication number: 20090082584
    Abstract: A process for initiating a highly selective ethylene oxide catalyst is provided in which the highly selective ethylene oxide catalyst is operated first as a ‘standard’ Ag-based catalyst (e.g., a catalyst that contains only silver and alkali metal, especially cesium). Moreover, the inventive initiation procedure is more efficient when the concentration of carbon dioxide in the feed is higher than 6 vol. %, and even more efficient when the concentration of carbon dioxide in the feed is higher than 10 vol. %, of the feed mixture during the initiation period.
    Type: Application
    Filed: September 26, 2007
    Publication date: March 26, 2009
    Applicant: SD LIZENZVERWERTUNGSGESELLSCHAFT MBH & CO. KG
    Inventors: Nabil Rizkalla, Barry Jay Billig, Norma B. Castagnola
  • Publication number: 20090069583
    Abstract: A method for controlling ethylene oxidation uses ethylene and oxygen, in conjunction with a silver based catalyst, a moderator and a co-moderator, to form ethylene oxide. When controlling the ethylene oxidation reaction, the moderator concentration is maintained constant within a comparatively narrow operative concentration range and the co-moderator concentration is varied within a comparatively wider operative concentration range, to optimize a catalyst property such as the catalyst activity and/or the catalyst selectivity.
    Type: Application
    Filed: September 11, 2007
    Publication date: March 12, 2009
    Applicant: SD LIZENZVERWERTUNGSGESELLSCHAFT MBH & CO. KG
    Inventors: Nabil RIZKALLA, Howard SACHS, Mansoor Firoz HUSAIN, Christian J. GUECKEL, Andrzej ROKICKI
  • Publication number: 20070037704
    Abstract: This invention relates to catalyst carriers to be used as supports for metal and metal oxide catalyst components of use in a variety of chemical reactions. More specifically, the invention provides a process of formulating a low surface area alpha alumina carrier that is suitable as a support for silver and the use of such catalyst in chemical reactions, especially the epoxidation of ethylene to ethylene oxide. A precursor for a catalyst support comprises an admixture of an alpha alumina and/or a transition alumina; a binder; and either a solid blowing agent which expands, or propels a gas upon the application of sufficient heat, and optionally contains talc and/or water soluble titanium compound.
    Type: Application
    Filed: August 10, 2005
    Publication date: February 15, 2007
    Inventor: Nabil Rizkalla
  • Publication number: 20070037991
    Abstract: This invention relates to catalyst carriers to be used as supports for metal and metal oxide catalyst components of use in a variety of chemical reactions. More specifically, the invention provides a process of formulating an alpha alumina carrier that is suitable as a support for silver and the use of such catalyst in chemical reactions, especially the epoxidation of ethylene to ethylene oxide. The composition comprises at least one hydrated precursor of alpha alumina; an optional alpha alumina; and a binder. The composition is substantially free of seeding particles.
    Type: Application
    Filed: August 10, 2005
    Publication date: February 15, 2007
    Inventor: Nabil Rizkalla
  • Patent number: 6939979
    Abstract: Ethylene is oxidized by contact at oxidizing conditions with an admixture of a solid particulate catalyst and a solid particulate alkali metal treated inert.
    Type: Grant
    Filed: November 10, 2003
    Date of Patent: September 6, 2005
    Assignee: Scientific Design Co., Inc.
    Inventors: Nabil Rizkalla, Vijay S. Bhise
  • Publication number: 20050101790
    Abstract: Ethylene is oxidized by contact at oxidizing conditions with an admixture of a solid particulate catalyst and a solid particulate alkali metal treated inert.
    Type: Application
    Filed: November 10, 2003
    Publication date: May 12, 2005
    Inventors: Nabil Rizkalla, Vijay Bhise
  • Patent number: 6858560
    Abstract: An ethylene oxide catalyst is provided which is essentially transition metal and rhenium free and which consists essentially of silver, alkali metal, sulfur and boron components on a support such as alumina, optionally with a fluorine or chlorine component.
    Type: Grant
    Filed: April 23, 2003
    Date of Patent: February 22, 2005
    Assignee: Scientific Design Co., Inc.
    Inventor: Nabil Rizkalla
  • Patent number: 6846774
    Abstract: The invention relates to an ethylene oxide catalyst comprised of silver deposited on an alumina carrier which has been treated to with an aqueous basic salt solution, the pH of the aqueous treating solution is maintained above 8 during the treatment.
    Type: Grant
    Filed: April 23, 2003
    Date of Patent: January 25, 2005
    Assignee: Scientific Design Co., Inc.
    Inventor: Nabil Rizkalla
  • Publication number: 20040215026
    Abstract: An ethylene oxide catalyst is provided which is essentially transition metal and rhenium free and which consists essentially of silver, alkali metal, sulfur and boron components on a support such as alumina, optionally with a fluorine or chlorine component.
    Type: Application
    Filed: April 23, 2003
    Publication date: October 28, 2004
    Inventor: Nabil Rizkalla
  • Publication number: 20040214719
    Abstract: The invention relates to an ethylene oxide catalyst comprised of silver deposited on an alumina carrier which has been treated to with an aqueous basic salt solution, the pH of the aqueous treating solution is maintained above 8 during the treatment.
    Type: Application
    Filed: April 23, 2003
    Publication date: October 28, 2004
    Inventor: Nabil Rizkalla
  • Patent number: 6762311
    Abstract: A silver catalyst for ethylene oxidation to ethylene oxide is provided containing a promoter combination consisting of critical amounts of an alkali metal component and a sulfur component, the catalyst being essentially free of rhenium and transition metal components; optionally the catalyst contains a fluorine component.
    Type: Grant
    Filed: November 13, 2001
    Date of Patent: July 13, 2004
    Assignee: Scientific Design Co., Ltd.
    Inventors: Nabil Rizkalla, Serguei Pak, Andrew D. Schmitz
  • Patent number: 6750173
    Abstract: The invention relates to an ethylene oxide catalyst comprised of silver deposited on an alumina carrier which has been treated to remove at least 25% of the surface sodium ions and replace the removed sodium ions with up to 10 ppm of lithium ions and to the preparation thereof.
    Type: Grant
    Filed: April 8, 2002
    Date of Patent: June 15, 2004
    Assignee: Scientific Design Company, Inc.
    Inventors: Nabil Rizkalla, Errrol Bornn, Charles W. Zulauf
  • Publication number: 20030191019
    Abstract: The invention relates to an ethylene oxide catalyst comprised of silver deposited on an alumina carrier which has been treated to remove at least 25% of the surface sodium ions and replace the removed sodium ions with up to 10 ppm of lithium ions and to the preparation thereof.
    Type: Application
    Filed: April 8, 2002
    Publication date: October 9, 2003
    Inventors: Nabil Rizkalla, Errrol Bornn, Charles W. Zulauf
  • Publication number: 20020107410
    Abstract: A silver catalyst for ethylene oxidation to ethylene oxide is provided containing a promoter combination consisting of critical amounts of an alkali metal component and a sulfur component, the catalyst being essentially free of rhenium and transition metal components; optionally the catalyst contains a fluorine component.
    Type: Application
    Filed: November 13, 2001
    Publication date: August 8, 2002
    Inventors: Nabil Rizkalla, Serguei Pak, Andrew D. Schmitz
  • Patent number: 6184175
    Abstract: An improved silver catalyst for the oxidation of ethylene with molecular oxygen is made by impregnating a porous support with a silver salt of an acid; subjecting the impregnated support to a multi-stage activation in an atmosphere containing less oxygen than air by heating at a first temperature in the range of 150 to 200° C. for less than an hour, heating at a second temperature in the range of from greater than 200° C. to 300° C. for less than one hour, heating at a third temperature in the range of from greater than 300° C. to 400° C. for less than one hour and finally heating at a fourth temperature in the range of from greater than 400° C. to 500° C.; and post impregnating the support with an alkali metal, preferably cesium, from an anhydrous alcohol solution followed by washing with alcohol solvent and rapid drying to produce a finished catalyst having from 1-6×10−3 gew of the alkali metal per kg of catalyst.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: February 6, 2001
    Assignee: Scientic Design Company, Inc.
    Inventor: Nabil Rizkalla
  • Patent number: 5958824
    Abstract: A silver catalyst for ethylene oxidation to ethylene oxide is provided containing a promoter combination consisting of an alkali metal component, a sulfur component, and a lanthanide component, the catalyst being essentially free of rhenium and transition metal components; optionally the catalyst contains a fluorine component.
    Type: Grant
    Filed: September 2, 1997
    Date of Patent: September 28, 1999
    Assignee: Scientific Design Co., Inc.
    Inventors: Nabil Rizkalla, Rita Klein, Stephen Bruce Milne