Abrasion Resistance Patents (Class 502/504)
  • Patent number: 7682423
    Abstract: Zinc oxide-based sorbents, and processes for preparing and using them are provided. The sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents comprise an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl2O4) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 500 Angstroms. Preferably the sorbents are prepared by converting a precursor mixture, comprising a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: March 23, 2010
    Assignee: Research Triangle Institute
    Inventors: Santosh Kumar Gangwal, Brian Scott Turk, Raghubir Prasael Gupta
  • Patent number: 7501375
    Abstract: This invention provides methods of making molecular sieve catalyst particles, molecular sieve slurries that can be used in such methods, molecular sieve catalyst compositions and their use in catalytic hydrocarbon conversion processes.
    Type: Grant
    Filed: June 14, 2007
    Date of Patent: March 10, 2009
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Yun-Feng Chang, Stephen N. Vaughn, Kenneth R. Clem, Luc R. Martens, Weiguo Hu
  • Patent number: 6951635
    Abstract: Zinc oxide-based sorbents, and processes for preparing and using them are provided, wherein the sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents contain an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl2O4) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 500 Angstroms. Preferably the sorbents are prepared by converting a precursor mixture, containing a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: October 4, 2005
    Assignee: Research Triangle Institute
    Inventors: Santosh Kumar Gangwal, Brian Scott Turk, Raghubir Prasad Gupta
  • Patent number: 6878668
    Abstract: A method for manufacturing of an attrition resistant vanadium/phosphorous oxide catalyst involving forming an aqueous slurry comprising; vanadium/phosphorous oxide catalyst or vanadium/phosphorous oxide catalyst precursor particles, an aqueous solution of H3PO4, and optionally an aqueous colloidal silica sol, an aqueous polysilicic acid solution or mixture thereof and then spray drying the slurry to form attrition resistant catalyst precursor followed by calcining/activating the spray dried precursor. Such a catalyst is particularly useful in oxidation processes such as the catalytic air oxidation of butane to maleic anhydride.
    Type: Grant
    Filed: July 11, 2000
    Date of Patent: April 12, 2005
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Jo-Ann T. Schwartz, Dwain T. Cline, Jr.
  • Patent number: 6812189
    Abstract: The disclosure is directed to sorbent compositions for removing reduced sulfur species (e.g., H2S, COS and CS2) a feed stream. The sorbent is formed from a multi-phase composition including a zinc titanate phase and a zinc oxide-aluminate phase. The sorbent composition is substantially free of unreacted alumina.
    Type: Grant
    Filed: April 3, 2000
    Date of Patent: November 2, 2004
    Assignees: Research Triangle Institute, Intercat, Inc.
    Inventors: Albert A. Vierheilig, Raghubir P. Gupta, Brian S. Turk
  • Patent number: 6620763
    Abstract: This process produces a sorbent for use in desulfurization of coal gas. A zinc titanate compound and a metal oxide are mixed by milling the compounds in an aqueous medium, the resulting mixture is dried and then calcined, crushed, sleved and formed into pellets for use in a moving-bed reactor. Metal oxides suitable for use as an additive in this process include: magnesium oxide, magnesium oxide plus molybdenum oxide, calcium oxide, yttrium oxide, hafnium oxide, zirconium oxide, cupric oxide, and tin oxide. The resulting sorbent has a percentage of the original zinc or titanium ions substituted for the oxide metal of the chosen additive.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: September 16, 2003
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Venkat S. Venkataramani, Raul E. Ayala
  • Patent number: 6107238
    Abstract: A method for manufacturing of an improved attrition resistant catalyst having an oxide-rich surface layer involving forming a slurry comprising; catalyst, catalyst precursor or catalyst support particles (e.g., transition metal oxides), a colloidal oxide sol (e.g., colloidal silica), and a solution of a solvent and solute wherein the solute consist essentially of a precursor of said oxide-rich surface with particle size no greater than 5 nm (e.g., aqueous silicic acid or polysilicic acid) and then spray drying the slurry to form porous microspheres of attrition resistant catalyst; and, calcining the spray dried microspheres. Such a catalyst is particularly useful in oxidation processes wherein the oxidation is performed by an oxidized form of the catalyst and the resulting reduced form of the catalyst is separately regenerated (e.g., two-step vapor phase processes carried out in recirculating solids reactors, transport bed reactors or circulating fluidized bed reactors and the like).
    Type: Grant
    Filed: September 30, 1998
    Date of Patent: August 22, 2000
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Rashmikant Maganlal Contractor, William Joseph Letts
  • Patent number: 5972835
    Abstract: The invention provides fluidizable, substantially spherical particulate material of improved attrition resistance having an average particle size from about 100 to about 400 microns useful as sorbents, catalysts, catalytic supports, specialty ceramics or the like. The particles are prepared by spray drying a slurry comprising inorganic starting materials and an organic binder. Exemplary inorganic starting materials include mixtures of zinc oxide with titanium dioxide, or with iron oxide, alumina or the like. Exemplary organic binders include polyvinyl alcohol, hydroxypropylemethyl cellulose, polyvinyl acetate and the like. The spray dried particles are heat treated at a first temperature wherein organic binder material is removed to thereby provide a porous structure to the particles, and thereafter the particles are calcined at a higher temperature to cause reaction of the inorganic starting materials and to thereby form the final inorganic particulate material.
    Type: Grant
    Filed: September 12, 1996
    Date of Patent: October 26, 1999
    Assignee: Research Triangle Institute
    Inventor: Raghubir P. Gupta
  • Patent number: 5962366
    Abstract: The durability and selectivity of a supported nobel metal hydrodeclorination catalyst can be improved by treating the supported catalyst, which comprises support and catalytic noble metal, with a late transition metal halide salt, a post transition metal containing halide salt, or a combination thereof, and with an alkali metal halide, ammonium halide, or a combination thereof. Suitable late transition metal and post transition metal halides for use herein include zinc chloride, tin chloride, and cupric chloride. A suitable alkali metal halide for use herein include lithium chloride. The novel resulting supported catalyst has its noble metal component, which is in the zero valent state, predominantly residing adjacent the surface of the support in a form which is predominantly visible under a microscope having a resolution of about 5 .ANG..
    Type: Grant
    Filed: October 8, 1998
    Date of Patent: October 5, 1999
    Assignee: Akzo Nobel N.V.
    Inventor: Zongchao Zhang
  • Patent number: 5721189
    Abstract: The durability of a supported noble metal hydrodechlorination catalyst can be improved by (1) treating the supported catalyst, which comprises support and catalytic noble metal, with a non-elemental halide compound, which is not a mineral acid (such as an alkali metal halide, an ammonium halide, an alkaline earth metal halide, and/or a halogenated hydrocarbon); and (2) then using the treated catalyst in a hydrodechlorination reaction. Suitable treatment compounds include ammonium chloride, lithium chloride, or a chlorinated hydrocarbon. The treated catalyst is a novel composition of matter comprising at least one platinum group metal supported by an oxidic support wherein the metal, which is in the zero valent state, predominantly resides adjacent the surface of the support and is predominantly visible under a microscope having a resolution of about 5 .ANG..
    Type: Grant
    Filed: November 21, 1996
    Date of Patent: February 24, 1998
    Assignee: Akzo Nobel N.V.
    Inventor: Zongchao Zhang
  • Patent number: 5468558
    Abstract: A process for preparing fracture-resistant sol/gel particles which contain silicon dioxide, in which a highly disperse filler is added to the aqueous alkali metal silicate solution and/or the aqueous acid solution used in the preparation process.
    Type: Grant
    Filed: May 14, 1993
    Date of Patent: November 21, 1995
    Assignee: Solvay Catalysts GmbH
    Inventors: Helmut Derleth, Karl H. Bretz
  • Patent number: 4755499
    Abstract: Novel sorbents comprising (a) an alumina substrate having a pore volume between 0.4 and 0.8 cc/g, and (b) an alkali or alkaline earth component, for example, sodium carbonate, wherein the amount of the alkali or alkaline earth component is between 50 and 400 .mu.g per m.sup.2 of the substrate. The sorbents of the present invention are outstandingly effective for the removal of nitrogen oxides, sulfur oxides and hydrogen sulfide from waste gas streams.
    Type: Grant
    Filed: September 9, 1986
    Date of Patent: July 5, 1988
    Assignee: Noxso Corporation
    Inventors: Lewis G. Neal, John L. Haslbeck, Hsiaopin Tseng
  • Patent number: 4621072
    Abstract: A process is disclosed for preparing coated catalysts, inter alia, for gas phase oxidations in organic chemistry, comprised of an inert support and a coating of catalyst material enclosing this support, wherein a suspension of the starting material for the coating is sprayed onto an agitated bed of the support, while the suspending medium is being partially removed by a gas stream, and the raw material is then dried and heat-treated. For this purpose, the support bed is mechanically agitated and loosened by a gas stream blown in from below. The catalyst precursor containing a binder and, if appropriate, a pore-former is sprayed in an increasing amount from above onto the bed, the ratio between suspending medium sprayed on and drawn off remaining about constant. The thermal expansion coefficient of the precursor as a dry powder must not deviate by more than 15% from that of the support.
    Type: Grant
    Filed: February 26, 1985
    Date of Patent: November 4, 1986
    Assignee: Degussa Aktiengesellschaft
    Inventors: Dietrich Arntz, Gunter Prescher, Werner Burkhardt, Johannes Heilos, Reinhard Manner
  • Patent number: 4452911
    Abstract: Activated bauxite particulate material having usual nominal particle size range of 20-50 mesh (U.S. Sieve Series) is treated by fluidization in an upflowing gas so as to attrite the particles and stabilize the particle shape and size, thereby making the catalyst more uniform in shape and resistent to attrition in subsequent ebullated bed reactor operations. The treated activated bauxite catalyst material is then rescreened to provide a narrower differential size range having a particle equivalent diameter ratio range for large to small particles of about 1.4-2.0, and a preferred 20-30 mesh (U.S. Sieve Series) particle size range. The selected pretreated catalyst is then introduced into the ebullated bed reactor of a hydrodemetallization process for hydrocarbon feedstocks containing high metals concentration.
    Type: Grant
    Filed: August 10, 1983
    Date of Patent: June 5, 1984
    Assignee: HRI, Inc.
    Inventors: Richard M. Eccles, Allen S. U. Li, Shyy-Jong D. Lin, Virginia A. Malik, Michael C. Chervenak