Patents by Inventor Nilanjan Brahma

Nilanjan Brahma 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: 7368409
    Abstract: A process for regenerating a palladium catalyst from a catalytic reaction where the catalyst is contaminated with at least carbon. The regenerating is conducted prior to any heating step under oxidizing conditions in the regenerating section. The regenerating involves at least one heating step under a hydrogen-containing reducing atmosphere and under conditions sufficient to lower the content of carbon in the palladium catalyst.
    Type: Grant
    Filed: May 9, 2003
    Date of Patent: May 6, 2008
    Assignee: Europeene de Retraitement de Catalyseurs-Eurecat
    Inventors: James Robinson, Nilanjan Brahma, Georges Mendakis, François Locatelli, Pierre Dufresnce
  • Publication number: 20040043890
    Abstract: Process for the regeneration of a solid catalyst or of a solid adsorbent wherein the catalyst or the adsorbent is used in the form of a bed in a regeneration zone, in which bed the catalyst is in motion, said process comprising at least one heating step under a reductive atmosphere.
    Type: Application
    Filed: May 9, 2003
    Publication date: March 4, 2004
    Applicant: EUROPEENNE DE RETRAITEMENT DE CATALYSEURS
    Inventors: James Robinson, Nilanjan Brahma, Georges Mendakis, Francois Locatelli, Pierre Dufresnce
  • Publication number: 20020098971
    Abstract: Process for the regeneration of a solid catalyst or of a solid adsorbent wherein the catalyst or the adsorbent is used in the form of a bed in a regeneration zone, in which bed the catalyst is in motion, said process comprising at least one heating step under a reductive atmosphere.
    Type: Application
    Filed: January 19, 2001
    Publication date: July 25, 2002
    Applicant: Europeenne De Retraitement De Catalyseurs-Eurecat
    Inventors: James Robinson, Nilanjan Brahma, Georges Mendakis, Francois Locatelli, Pierre Dufresnce
  • Patent number: 6294498
    Abstract: Process for passivation of a heterogenous catalyst of refining reactions or hydrocarbon hydroconversion reactions, characterized in that the external surface of the particles of said heterogeneous catalyst is coated with a protective layer that is made of a particularly inert material which can be eliminated in the reaction zone under the conditions of the reaction.
    Type: Grant
    Filed: August 11, 1998
    Date of Patent: September 25, 2001
    Assignee: Europeenne de Retraitement de Catalyseurs Eurecat
    Inventors: Joan Darcissac, Franck Labruyere, Nilanjan Brahma, Pierre Dufrense
  • Patent number: 6100216
    Abstract: A process for presulfurizing a hydrocarbon treatment catalyst and/or for preconditioning a catalyst, comprising one or two stages of incorporating sulfur into the pores of a hydrocarbon conversion catalyst conducted off-site in at least one zone that contains a catalyst, preferably in motion, and with either suilirated hydrogen (H.sub.2 S), sulfur, or a sulfur compound capable of evolving nascent suilirated hydrogen.
    Type: Grant
    Filed: January 16, 1997
    Date of Patent: August 8, 2000
    Assignee: Europeenne de Retraitement de Catalyseurs Eurecat
    Inventors: Pierre Dufresne, Nilanjan Brahma, Jean Darcissac, Franck Labruyere
  • Patent number: 6077803
    Abstract: A process for presulfurizing a refining catalyst or petrochemical catalyst consists of bringing a catalyst into contact with liquid elementary sulfur or elementary sulfur dissolved in a liquid, preferably another sulfur compound such as an organic polysulfide, in the presence of a stabilizing agent, e.g., a fatty acid, mercaptan or alcohol.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: June 20, 2000
    Assignee: Europeene de Retraitment de Catalyseurs
    Inventors: Pierre Dufresne, Nilanjan Brahma
  • Patent number: 5985787
    Abstract: The invention concerns a novel presulphuration process for a hydrocarbon conversion catalyst. Presulphuration is preferably carried out offsite (ex-situ). The catalyst presulphuration process is characterized in that a presulphuration agent is used which contains (a) at least one first sulphur compound with a decomposition point T1 of less than 220.degree. C. and (b) at least one second sulphur compound with a decomposition point greater than about 220.degree. C.
    Type: Grant
    Filed: June 14, 1994
    Date of Patent: November 16, 1999
    Assignee: Europenne De Retraitement De Catalyseurs Eurecat
    Inventors: Pierre Dufresne, Nilanjan Brahma, Stephen R. Murff
  • Patent number: 5922638
    Abstract: The invention relates to a process for ex-situ presulfurization of porous particles of a hydrocarbon hydroconversion catalyst that contains at least one metal or metal oxide, comprising bringing catalytic particles into contact with a presulfurizing agent that contains elementary sulfur and at least one organic liquid. It is characterized in that the process comprises preparing the presulfurizing agent in the form of an essentially homogeneous liquid and impregnating the catalyst particles with said liquid, with said elementary sulfur consequently being incorporated for the most part into the pores of the catalyst.
    Type: Grant
    Filed: June 24, 1997
    Date of Patent: July 13, 1999
    Assignee: Europeene de Retraitement de Catalyseurs Eurecat
    Inventors: Pierre Dufresne, Nilanjan Brahma
  • Patent number: 5854162
    Abstract: The invention concerns a process for the regeneration of a used hydrocarbon treatment catalyst, preferably a reforming catalyst, containing at least one precious metal preferably platinum, optionally at least one additional metal selected from the group formed by metals from groups 7, 8, 9, 10, 13 and 14 of the periodic classification of the elements and copper, optionally and preferably at least one halogen, preferably chlorine, and at least one porous support, preferably alumina, said process comprising at least one of the following two successive steps: at least one step (1) for the combustion of the coke present on said catalyst, carried out in the presence of an oxygen-containing gas, at a temperature in the range of 300.degree. C. to 680.degree. C. for a time in the range 0.3 to 7 hours, at least one step (2) for oxyhalogenation, preferably oxychlorination, carried out in a controlled air atmosphere, at a temperature in the range 350.degree. C. to 550.degree. C., for a time in the range 0.
    Type: Grant
    Filed: October 14, 1997
    Date of Patent: December 29, 1998
    Assignee: Europeenne de Retraitement de Catalyseurs Eurecat
    Inventors: Pierre Dufresne, Nilanjan Brahma
  • Patent number: 5482616
    Abstract: This invention relates to a catalyst for hydrogenation and/or dehydrogenation having an improved resistance against deactivation by sulfur compounds, comprising at least one hydrogenation component, at least one metal-oxide containing component and at least one component acting as a support material, in which at least a part of the hydrogenation component and a part of the metal-oxide containing component are present on said support material as separate particles, the particles of the hydrogenation component and the particles of the metal-oxide containing component being homogeneously distributed in the catalyst.
    Type: Grant
    Filed: May 26, 1992
    Date of Patent: January 9, 1996
    Assignee: Engelhard De Meern B. V.
    Inventors: Nilanjan Brahma, John W. Geus, Eugene G. M. Kuijpers