Abstract: The present invention is directed to an improved catalyst support and to the resultant catalyst suitable for treating exhaust products from internal combustion engines, especially diesel engines. The support of the present invention is a structure comprising alumina core particulate having high porosity and surface area, wherein the structure has from about 1 to about 40 weight percent silica in the form of cladding on the surface area of said alumina core. The resultant support has a normalized sulfur uptake (NSU) of up to 15 ?g/m2.

Abstract: The present invention is directed to an improved catalyst support and to the resultant catalyst suitable for treating exhaust products from internal combustion engines, especially diesel engines. The support of the present invention is a structure comprising alumina core particulate having high porosity and surface area, wherein the structure has from about 1 to about 40 weight percent silica in the form of cladding on the surface area of said alumina core. The resultant support has a normalized sulfur uptake (NSU) of up to 15 ?g/m2.

Abstract: Mixed oxides of cerium oxide and zirconium oxides having a high oxygen storage and high oxygen release rate are disclosed. The mixed oxides are made of polycrystalline particles of cerium oxide and zirconium oxide having a controlled domain structure on the subcrystalline level wherein adjacent domains within a single crystallite have a different ratio of zirconium and cerium. The mixed oxides are prepared by a co-precipitation technique using mixed salt solutions of cerium and zirconium having a solid content of at least 23%, based on an oxide basis.

Abstract: Mixed oxides of cerium oxide and zirconium oxides having a high oxygen storage and high oxygen release rate are disclosed. The mixed oxides are made of polycrystalline particles of cerium oxide and zirconium oxide having a controlled domain structure on the subcrystalline level wherein adjacent domains within a single crystallite have a different ratio of zirconium and cerium. The mixed oxides are prepared by a co-precipitation technique using mixed salt solutions of cerium and zirconium having a solid content of at least 23%, based on an oxide basis.

Abstract: A process for the preparation of mixed oxide compositions of cerium oxide and at least one non-noble metal oxide is disclosed. The process involves contacting a salt solution containing a cerium (IV) salt with hydrogen peroxide and thereafter, treating the resulting solution with excess base to precipitate a mixed oxides. Mixed oxide compositions produced by the process maintain a high specific surface area after prolonged exposure to high temperatures.

Abstract: A method for producing by electrophoretic deposition multi-layer, polyfunctional, catalyst members for use in catalytic converters having a plurality of suitably porous and adherent catalyst support coatings of substantially uniform thickness, a plurality of non-identical catalytic agents imbued therein/on, and a flexible metal substrate, are disclosed. Such process involves maintaining electrical interaction between a metal substrate previously coated with catalyst-catalyst support material, the power source, and the electrodes disposed in the electrophoretic deposition ("EPD") cell containing a slurry of a second catalyst support material and a second catalyst composition non-identical to that found in the first catalytically-active layer.

Abstract: A powder composition of ceric oxide and a stabilizing non-noble metal oxide, such as zirconium oxide, mixed at the atomic level in complete solid solution. The powder is used to form washcoats for catalytic converters. The composition has high oxygen storage capacity and maintains an ultrafine crystallite size at high temperatures. The powder is formed by a spray pyrolysis process that includes atomizing a clear solution of cerium ions and ions of the non-noble metal into a fine mist that is passed rapidly through a furnace to form powder particles.

Abstract: A powder composition of ceric oxide and a stabilizing non-noble metal oxide, such as zirconium oxide, mixed at the atomic level in complete solid solution. The powder is used to form washcoats for catalytic converters. The composition has high oxygen storage capacity and maintains an ultrafine crystallite size at high temperatures. The powder is formed by a spray pyrolysis process that includes atomizing a clear solution of cerium ions and ions of the non-noble metal into a fine mist that is passed rapidly through a furnace to form powder particles.

Abstract: A method for producing by electrophoretic deposition multi-layer, polyfunctional, catalyst members for use in catalytic converters having a plurality of suitably porous and adherent catalyst support coatings of substantially uniform thickness, a plurality of non-identical catalytic agents imbued therein/on, and a flexible metal substrate, are disclosed. Such process involves maintaining electrical interaction between a metal substrate previously coated with catalyst-catalyst support material, the power source, and the electrodes disposed in the electrophoretic deposition ("EPD") cell containing a slurry of a second catalyst support material and a second catalyst composition non-identical to that found in the first catalytically-active layer.

Abstract: A barrier is formed on a metal substrate by coating the substrate with a metal oxide, calcining the substrate, impregnating the coated substrate with an acid, and calcining the impregnated coating at a temperature high enough to cause the metal oxide to form the barrier. The resulting barrier acts as an excellent electrical insulator, and also provides improved resistance to abrasion, and improved adhesion to the substrate. The particles forming the barrier also have improved cohesion. The metal substrate having the barrier of the present invention can be used in electrically heated catalytic converters, where it is necessary to provide closely spaced layers of metal foil that must be electrically insulated from each other. The invention can also be used in other metal structures intended to be placed in the exhaust stream of a chemical or manufacturing process or an engine.

Abstract: Flexible metal foil catalyst members suitable for use in catalytic devices for combustion engine emission control are prepared by electrophoretic deposition using an aqueous slurry of catalyst support particles. The deposited support layer is of uniform thickness and stable surface area. The catalyst support may then be impregnated with catalytic species and assembled into a catalytic device. The catalyst members from the invention are especially suitable for use in automotive applications, and more especially in electrically heated catalytic devices.

Abstract: Flexible metal foil catalyst members suitable for use in catalytic devices for combustion engine emission control are prepared by electrophoretic deposition using an aqueous slurry of catalyst support particles. The deposited support layer is of uniform thickness and stable surface area. The catalyst support may then be impregnated with catalytic species and assembled into a catalytic device. The catalyst members from the invention are especially suitable for use in automotive applications, and more especially in electrically heated catalytic devices.

Abstract: A bioremediation support for the support of microorganisms used in the biotreatment of an aqueous waste stream or contaminated vapor is made of a low-density siliceous glassy material. This material has a cellular or frothy texture, large pores of greater than 1,000 Anstrom units in diameter dispersed throughout the material, a high macropore volume in pores of greater than 1,000 .ANG. of more than 0.3 cc/cc and a BET surface area of greater than 10 m.sup.2 /g. A preferred material is pumice.

Abstract: Porous monolithic ceramic bodies containing reticulated macropores are produced by:a) forming a mixture of ceramic material particles, a first organic material and a second organic material,b) dissolving the first and second organic materials in each other to form a homogeneous solution, whereby the ceramic particles form a dispersion in the homogenous solution,c) forming the dispersion into a shape,d) cooling the shape at a rate sufficient to induce the non-equilibrium phase separation, thereby forming a first phase rich in the first organic material and a second phase rich in the second organic material, wherein at least a portion of the ceramic particles are segregated in the first phase,e) removing the second phase from the phase separated shape to form a porous shape,f) firing the porous shape to remove the any of the organic materials contained in the first phase and to sinter the segregated ceramic particles to form the porous monolithic ceramic body.

Abstract: A bioremediation support for the support of microorganisms used in the biotreatment of an aqueous waste stream or contaminated vapor is made of a low-density siliceous glassy material. This material has a cellular or frothy texture, large pores of greater than 1,000 Anstrom units in diameter dispersed throughout the material, a high macropore volume in pores of greater than 1,000 .ANG. of more than 0.3 cc/cc and a BET surface area of greater than 10 m.sup.2 /g. A preferred material is pumice.

Abstract: Ceramic beads having a bimodal pore distribution are prepared by a process involving a) formation of a ceramic particle slurry, b) adding a foamable prepolymer to the slurry to form a mixture, c) dispersing the mixture as beads in a second liquid, d) polymerizing and foaming the prepolymer, e) recovering the beads and firing them to remove the polymer and bond the ceramic particles. The beads can optionally be joined by sintering. Beads with a monodal pore distribution can be made by using a non-foaming prepolymer.

Abstract: Ceramic beads having a bimodal pore distribution are prepared by a process involving a) formation of a ceramic particle slurry, b) adding a foamable prepolymer to the slurry to form a mixture, c) dispersing the mixture as beads in a second liquid, d) polymerizing and foaming the prepolymer, e) recovering the beads and firing them to remove the polymer and bond the ceramic particles. The beads can optionally be joined by sintering. Beads with a monodal pore distribution can be made by using a nonfoaming prepolymer.

Abstract: Monolithic bodies of sinterable materials are formed by a sintering process in which little or no shrinkage of the body occurs during sintering. In the method, large particles are placed in particle-to-particle contact with finer size powder particles at the interstices to form a molded shape which is then fired. During firing, the large particles are substantially stable, but the fine powder particles sinter to bond the large particles together. The method is especially useful for producing large and/or intricately shaped bodies. The method is also especially useful for making monolithic bodies using large hollow spherical particles.