Abstract: Precipitated silica having large median particle size for use as reinforcing filler in elastomeric compositions as well as its method of manufacture. In particular, a precipitated silica characterised by a CTAB surface area SCTAB in the range from 70 to 350 m2/g; an amount WM of at least one metal M selected from elements of groups 3, 4 and 5 of at least 0.1 mol %; and a median particle size d50, measured by centrifugal sedimentation, such that: |d50|?183×|RION|×|WM|?0.67×|SCTAB|+233 (I) wherein |d50| represents the numerical value of median particle size d50 measured by centrifugal sedimentation and expressed in nm; |RION|, the numerical value of the ionic radius of metal M expressed in nm; |SCTAB|, the numerical value of the CTAB surface area SCTAB expressed in m2/g; and |WM|, the numerical value of the percentage molar amount of the metal WM.

Abstract: The present disclosure includes a housing including an installation space formed therein, an inlet through which an external gas flows into the installation space, and an outlet through which a gas inside the installation space is discharged to the outside, a first ozone decomposition unit installed in the installation space of the housing to decompose ozone in the external gas flowing into the installation space inside the housing through the inlet, and a second ozone decomposition unit installed in the installation space of the housing to receive the gas decomposed by the first ozone decomposition unit and decompose residual ozone in the gas.

Abstract: Catalyst compositions containing a metallocene compound, a solid activator, and a co-catalyst, in which the solid activator or the supported metallocene catalyst has a d50 average particle size of 15 to 50 ?m and a particle size distribution of 0.5 to 1.5, can be contacted with an olefin in a loop slurry reactor to produce an olefin polymer. A representative ethylene-based polymer produced using the catalyst composition has excellent dart impact strength and low gels, and can be characterized by a HLMI from 4 to 10 g/10 min, a density from 0.944 to 0.955 g/cm3, a higher molecular weight component with a Mn from 280,000 to 440,000 g/mol, and a lower molecular weight component with a Mw from 30,000 to 45,000 g/mol and a ratio of Mz/Mw ranging from 2.3 to 3.4.

Abstract: Catalyst compositions containing a metallocene compound, a solid activator, and a co-catalyst, in which the solid activator or the supported metallocene catalyst has a d50 average particle size of 15 to 50 ?m and a particle size distribution of 0.5 to 1.5, can be contacted with an olefin in a loop slurry reactor to produce an olefin polymer. A representative ethylene-based polymer produced using the catalyst composition has excellent dart impact strength and low gels, and can be characterized by a HLMI from 4 to 10 g/10 min, a density from 0.944 to 0.955 g/cm3, a higher molecular weight component with a Mn from 280,000 to 440,000 g/mol, and a lower molecular weight component with a Mw from 30,000 to 45,000 g/mol and a ratio of Mz/Mw ranging from 2.3 to 3.4.

Abstract: Processes for forming multimetallic catalysts by grafting nickel precursors to metal oxide supports. Dry reforming reaction catalysts having nickel and promotors grafted to metal oxides supports. Methanation reaction catalysts having nickel and promotors grafted to metal oxides supports.

Abstract: An improved hydrotreating catalyst and process for making a base oil product wherein the catalyst comprises a base extrudate that includes a high nanopore volume amorphous silica alumina (ASA) and a second amorphous silica alumina. The catalyst and process generally involve the use of a base extrudate comprising the high nanopore volume ASA and the second ASA in a catalyst to produce hydrotreated dewaxed base oil products by contacting the catalyst with a hydrocarbon feedstock. The catalyst base extrudate advantageously comprises a first amorphous silica alumina having a pore volume in the 11-20 nm pore diameter range of 0.2 to 1.0 cc/g and a second amorphous silica alumina having a pore volume in the 11-20 nm pore diameter range of 0.02 to 0.2 cc/g, with the base extrudate formed from the amorphous silica alumina and the alumina having a total pore volume in the 2-50 nm pore diameter range of 0.12 to 1.80 cc/g.

Abstract: The present application discloses a supported PtZn intermetallic alloy catalyst, a method for preparing the same and application thereof. The catalyst uses SiO2 as a support and Zn as a promoter, and a small amount of active component Pt is supported; the weight percentage of Pt is 0.025%-1%, and the weight percentage of Zn is 0.025%-1.7%, a co-impregnation method is adopted in preparation, the SiO2 support is impregnated in aqueous solution of chloroplatinic acid and zinc nitrate, and then drying and high-temperature reduction are performed to obtain a PtZn/SiO2 catalyst. The catalyst has the advantages of high activity, high stability, low price and low toxicity. The catalyst provided by the present application is applicable to preparation of alkene through short-chain alkane dehydrogenation, in particular to preparation of propylene through propane dehydrogenation in a hydrogen atmosphere.

Abstract: It is provided a process of producing amorphous silica from a raw material, such as serpentine, containing silica comprising the steps of mixing the raw material with a hydrochloric acid solution; leaching the raw material obtaining a slurry comprising a liquid fraction and a solid fraction containing silica and minerals; separating the liquid fraction and the solid fraction; removing the minerals from the solid fraction by magnetic separation producing a purified solid silica; drying the purified solid silica; and heating the purified solid silica to remove hydroxyl groups from the silica surface and reducing specific surface area of the resulting amorphous silica.

Abstract: The invention relates to a copper manganese-based catalyst on the basis of a tablet-form shaped catalyst body, comprising calcium aluminate as a binder, for hydrating carbonyl groups in organic compounds, characterised in that said shaped catalyst body comprises calcium aluminate in an amount of 0.5 to 20 wt. %. The invention also relates to the production of the catalyst and to the use of same in the hydration of carbonyl groups in organic compound.

Abstract: A bulk metal oxide catalyst composition of the general formula (X)b(M)c(Z)d(O)e??(I) wherein X represents at least one non-noble Group VIII metal; M represents at least one non-noble Group VIb metal; Z represents one or more elements selected from aluminum, silicon, magnesium, titanium, zirconium, boron, and zinc; one of b and c is the integer 1; and d and e and the other of b and c each are a number greater than 0 such that the molar ratio of b:c is in the range of from 0.5:1 to 5:1, the molar ratio of d:c is in the range of from 0.2:1 to 50:1, and the molar ratio of e:c is in the range of from 3.7:1 to 108:1; is prepared by controlled (co)precipitation of component metal compounds, refractory oxide material, and alkali compound in protic liquid. Resulting compositions find use in hydrotreatment processes involving particularly hydrodesulphurization and hydrodenitrification.

Abstract: A particulate catalytic cracking catalyst which comprises a zeolite having catalytic cracking ability under catalytic cracking conditions, added silica, precipitated alumina and, optionally clay. The catalytic cracking catalyst has a high matrix surface area and is useful in a catalytic cracking process, in particularly, a fluid catalytic cracking process, to improve bottoms conversion at a constant coke formation.

Abstract: Provided is a process for producing, in a single step, hydrocarbon fractions useful as diesel fuel or as a component of diesel fuel, from a mixture of a biological origin containing esters of fatty acids and, optionally, aliquots of free fatty acids. The process comprises the contemporaneous hydrodeoxygenation and hydroisomerization of the mixture of a biological origin, with the formation of linear and branched paraffins. The process is carried out in the presence of a catalytic composition comprising an amorphous carrier of an acidic nature and a metallic component containing one or more metals of group VIII.

Abstract: Disclosed is a catalyst for use in production of carboxylic acid ester by reacting (a) aldehyde and alcohol, or (b) one or more types of alcohols, in the presence of oxygen; wherein oxidized nickel and X (wherein X represents at least one element selected from the group consisting of nickel, palladium, platinum, ruthenium, gold, silver and copper) are loaded onto a support within the range of the atomic ratio of Ni/(Ni+X) of from 0.20 to 0.99.

Abstract: The present invention relates to a catalyst for preparing a carbon nanotube having desired apparent density by controlling the adding amount of co-precipitating agent in the process of preparing a catalyst in order to obtain a catalyst having a minimized particle size. More specifically, this invention relates to a catalyst for preparing carbon nanotube having desired apparent density based upon the reverse-correlation between the amount of co-precipitating agent added in the process of preparing catalyst and the apparent density of catalyst. The carbon nanotube prepared by the catalyst having low apparent density shows excellent electrical conductivity and highly uniformed dispersion in the polymer/carbon nanotube composite.

Abstract: A bulk metal oxide catalyst composition of the general formula (X)b(M)c(Z)d(O)e??(I) wherein X represents at least one non-noble Group VIII metal; M represents at least one non-noble Group VIb metal; Z represents one or more elements selected from aluminum, silicon, magnesium, titanium, zirconium, boron, and zinc; one of b and c is the integer 1; and d and e and the other of b and c each are a number greater than 0 such that the molar ratio of b:c is in the range of from 0.5:1 to 5:1, the molar ratio of d:c is in the range of from 0.2:1 to 50:1, and the molar ratio of e:c is in the range of from 3.7:1 to 108:1; is prepared by controlled (co)precipitation of component metal compounds, refractory oxide material, and alkali compound in protic liquid. Resulting compositions find use in hydrotreatment processes involving particularly hydrodesulphurization and hydrodenitrification.

Abstract: A catalyst for converting methanol to light olefins and the process for making and using the catalyst are disclosed and claimed. SAPO-34 is a specific catalyst that benefits from its preparation in accordance with this invention. A seed material is used in making the catalyst that has a higher content of the EL metal than is found in the principal part of the catalyst. The molecular sieve has predominantly a roughly rectangular parallelepiped morphology crystal structure with a lower fault density and a better selectivity for light olefins.

Abstract: Methods and systems for contacting of a crude feed with one or more catalysts to produce a total product that includes a crude product are described. The crude product is a liquid mixture at 25° C. and 0.101 MPa. The crude product has an MCR content of at most 90% of the MCR content of the crude feed. One or more other properties of the crude product may be changed by at least 10% relative to the respective properties of the crude feed.

Abstract: A silicoaluminophosphate molecular sieve is disclosed that comprises first and second intergrown phases of a CHA framework type and an AEI framework type, wherein said first intergrown phase has an AEI/CHA ratio of from about 5/95 to about 40/60 as determined by DIFFaX analysis, the second intergrown phase has an AEI/CHA ratio of about 30/70 to about as determined by DIFFaX analysis and said molecular sieve has a silica to alumina molar ratio (Si/Al2) from about 0.13 to about 0.24.

Abstract: In one embodiment, a reforming catalyst can include indium, tin, and a catalytically effective amount of a group VIII element for one or more reforming reactions. Typically, at least about 25%, by mole, of the indium is an In(3+) species based on the total moles of indium after exposure for about 30 minutes in an atmosphere including about 100% hydrogen, by mole, at a temperature of about 565° C. Usually, no more than about 25%, by mole, of the tin is a Sn(4+) species based on the total moles of tin after exposure for about 30 minutes in an atmosphere including about 100% hydrogen, by mole, at a temperature of about 565° C.

Abstract: Amorphous porous solid of an acidic nature, with a controlled pore size, essentially consisting of a mixed oxide of silicon, aluminum and phosphorous, having a surface area of at least 200 m2/g, which can be used as a catalyst or active carrier of a catalyst for various industrial processes, such as, for example, alkylation, isomerization, hydro-dehydrogenation processes, with an improved activity and selectivity with respect to the traditional amorphous silica-alumina gels.

Abstract: A bulk metal oxide catalyst composition of the general formula (X)b(M)c(Z)d(O)e??(I) wherein X represents at least one non-noble Group VIII metal; M represents at least one non-noble Group VIb metal; Z represents one or more elements selected from aluminium, silicon, magnesium, titanium, zirconium, boron, and zinc; one of b and c is the integer 1; and d and e and the other of b and c each are a number greater than 0 such that the molar ratio of b:c is in the range of from 0.5:1 to 5:1, the molar ratio of d:c is in the range of from 0.2:1 to 50:1, and the molar ratio of e:c is in the range of from 3.7:1 to 108:1; is prepared by controlled (co)precipitation of component metal compounds, refractory oxide material, and alkali compound in protic liquid. Resulting compositions find use in hydrotreatment processes involving particularly hydrodesulphurisation and hydrodenitrification.

Abstract: The invention relates to highly active spherical metal support catalysts with a metal content of 10 to 70% by mass, and a process for their production with the use of a mixture of polysaccharides and at least one metal compound which is dropped into a metal salt solution.

Abstract: A coated metal substrate useful for carrying an exhaust emission treatment catalyst such as a three-way conversion catalyst for use with small engine platforms. The coated metal substrate comprises a metal such as a stainless steel, a carbon steel, a FeCr alloy, HASTELLOY® and the like. The coating on the metal substrate comprises an alumina silicate having alumina particles impregnated therein. The coating is applied using a liquid dispersion containing an aluminum silicate and the alumina particles are dispersed into the aluminum silicate coating while the coating is still wet. The coated metal substrate is then calcined. Thereafter, a washcoat containing an engine exhaust treatment catalyst may be applied to the surface of the coated metal substrate.

Abstract: Alumina-silica catalyst supports having substantially high surfaces areas are formed by extrusion, drying and firing of a plasticized batch including an alumina-silica powder component, acid, organic binder and water. The alumina-silica powder component can be formed either by the mixing of alumina- and silica-source powders or by forming a slurry therefrom which is spray dried to form a particulate material prior to batching.

Abstract: A process for preparing a transalkylation catalyst, the catalyst itself, and a transalkylation process for using the catalyst are herein disclosed. The catalyst comprises rhenium metal on a solid-acid support such as mordenite, which has been treated with a sulfur-based agent. Such treatment reduces the amount of methane produced by metal hydrogenolysis in a transalkylation process wherein heavy aromatics like A9+ are reacted with toluene to produce xylenes. Reduced methane production relative to total light ends gas production results in lower hydrogen consumption and lower reactor exotherms.

Abstract: A method and device for loading a catalyst into a chamber. The catalyst loading is well suited for production of hydrogen producing microreactors. The catalyst is coated onto a strip which is mountable within the chamber.

Abstract: A catalyst, a process for using the catalyst whereby the catalyst effectively transalkylates C7, C9, and C10 aromatics to C8 aromatics are disclosed. The catalyst comprises a support such as mordenite plus a metal component. The catalyst provides an enhanced life and activity for carrying out the transalkylation reactions at relatively low temperatures. This is achieved by reducing the maximum particle diameter of cylindrical pellets to 1/32 inch (0.08 cm) or a trilobe to 1/16 inch (0.16 cm).

Abstract: The invention relates to highly active spherical metal support catalysts with a metal content of 10 to 70% by mass, and a process for their production with the use of a mixture of polysaccharides and at least one metal compound which is dropped into a metal salt solution.

Abstract: This invention relates to a catalyst system comprising a catalyst and a support comprising a non-layered inorganic porous crystalline phase material, wherein the support comprises a hexagonal arrangement of uniformly-sized pores having an average pore diameter greater than or equal to about 13 ?, an X-ray diffraction pattern having a calculated d100 value of greater than or equal to about 18 ?, an adsorption capacity of greater than or equal to about 15 grams benzene per 100 grams support at 50 torr and at 25° C., and a pore wall thickness of less then or equal to about 25 ?.

Abstract: The present invention is directed to an attrition resistant carrier product such as silica. Further, this invention is directed to the use of a binder to improve the attrition resistance or reduce the friability of a carrier product such as silica. In an embodiment, the median particle size is from 125 to 300 microns. Selection of the binder is such that the presence and/or addition of the binder does not result in substantial modification of the physical properties of the silica. Suitable binders include Group I and Group II silicates, Group I and Group II aluminates, and mixtures thereof, as identified by the Period Table of Elements.

Abstract: A spherical porous ceramic body and the production method thereof are provided. As to the porous ceramic body, the total volume of the pores having a pore radius of from 1.8 nm to 100 ?m is about 0.25 cm3/g or more, the mode of pore radius of the pores is from about 1 ?m to about 6 ?m and the packing density is from about 0.7 g/cm3 to about 1 g/cm3. The porous ceramic body is suitably used as a carrier for a catalyst and has high mechanical strength.

Abstract: The present invention is directed to a novel one-step method for forming a supported catalyst complex of high activity by substantially simultaneously contacting a bidentate or tridentate ligand forming compound, a transition metal compound and a Lewis acid support-activator agglomerate. The catalyst can be formed prior to polymerization of olefins or within the polymerization reaction zone.

Abstract: A robust, high temperature mixed metal oxide catalyst for propellant composition, including high concentration hydrogen peroxide, and catalytic combustion, including methane air mixtures. The uses include target, space, and on-orbit propulsion systems and low-emission terrestrial power and gas generation. The catalyst system requires no special preheat apparatus or special sequencing to meet start-up requirements, enabling a fast overall response time. Start-up transients of less than 1 second have been demonstrated with catalyst bed and propellant temperatures as low as 50 degrees Fahrenheit. The catalyst system has consistently demonstrated high decomposition effeciency, extremely low decomposition roughness, and long operating life on multiple test particles.

Abstract: This invention relates to a method for purifying and drying a polymer hydrogel. This invention is based in part upon the discovery that rapid drying of polymer hydrogels can eliminate the problem of unacceptable levels of soluble oligomers caused by prolonged thermal treatment. Rapid drying techniques allow drying hydrogels containing more water than was previously considered possible without a loss in product quality. Furthermore, it was discovered that slurries comprising polymer hydrogels and large quantities of water can be spray dried and that spray drying can be conducted with only minimal oligomer formation.

Abstract: A mullite composition is comprised substantially of mullite grains that are essentially chemically bound wherein the composition has at least two adjoining regions that have substantially different microstructures. The composition may be produced by forming a mixture of one or more precursor compounds having the elements present in mullite; shaping the mixture into a porous green shape applying a nucleation control agent to a portion of the porous green shape and then heating the porous green shape under an atmosphere and to a temperature sufficient to form the mullite composition.

Abstract: The present invention provides a metallocene catalyst supported on a molecular seive having “tubules-within-a-tubule” morphology. When the metallocene catalyst is used for preparing polyolefin, the MAO amount can be decreased to an amount such that the molar ratio of Al/Zr is below 200. Thus, production costs are greatly reduced.

Abstract: The present invention provides a process for producing spherical catalyst carrier of silica, silica-alumina composition, zirconia-alumina composition, titania-alumina composition, boria-alumina composition, or boria-silica-alumina composition which has almost the same pore characteristics as alumina hydrate gel, silica-alumina hydrate gel, zirconia-alumina hydrate gel, or titania-alumina hydrate gel (or alumina hydrate paste, boria-alumina hydrate paste, or boria-silica-alumina hydrate paste) as the major raw material, has uniform sphericity and smooth surface and homogeneity, and has a macropore volume that can be controlled.

Abstract: A base catalyst, obtained by formulating at least one alkali metal compound selected from the group consisting of alkoxides, hydroxides and oxides of alkali metals and an alkaline-earth metal oxide in a ratio of “the weight of alkaline metal compound/the weight of alkaline-earth metal oxide”=0.005 to 1, is used in a reaction of an aldehyde to produce a glycol monoester, thereby providing a base catalyst with an improved efficiency which can be applied to aldol reaction or the like and which has high activity to give target product in a high selectivity.

Abstract: Moldings are disclosed for use as a catalyst or catalyst support for hydrating olefin, such as ethylene and propylene. The moldings are based on a pyrogenically produced mixed oxide having the following physicochemical parameters: External diameter 0.8-25 mm BET surface area 5-400 m2/g Pore volume 0.2-1.8 ml/g Fracture strength 5 to 350 N Composition At least two materials selected from the group of SiO2, Al2O3, TiO2 and ZrO2 in any desired combination, with the proviso that when the combination is a SiO2/Al2O3 mixed oxide, at least 75 wt. % of SiO2 is present based on the total weight of the mixed oxide. Other constituents <1 wt. % Bulk density 250-1500 g/l.

Abstract: Aluminum-magnesium silicate- or fluorinated magnesium silicate- aerogels which may be calcined, chemically modified, ion-exchanged, agglomerated, used as a component of a catalyst composition for an addition polymerization; supported versions thereof; and processes for polymerization are disclosed.

Abstract: Silica powders and mixed silica-oxide powders and methods of preparing such powders for use as catalyst supports for polymerization processes.

Abstract: Frangible, spray dried agglomerate catalyst supports are provided, e.g. of silica gel, which possess a controlled morphology of microspheroidal shape, rough, scabrous appearance, and interstitial void spaces which penetrate the agglomerate surface and are of substantially uniform size and distribution. The agglomerates also possess a 1-250 micron particle size, 1-1000 m2/gm. surface area, and an Attrition Quality Index (AQI) of at least 10. The agglomerates are derived from a mixture of dry milled inorganic oxide particles, e.g. silica gel, and optionally but preferably wet milled inorganic oxide particles, e.g. silica gel particles, (which preferably contain a colloidal segment of <1 micron particles) slurried in water for spray drying. The high AQI assures that the agglomerates are frangible and that polymerization performance is improved.

Abstract: A method of making frangible, spray dried agglomerate catalyst supports is provided, e.g. of silica gel, which possess a controlled morphology of microspheroidal shape, preferably a rough, scabrous appearance, and interstitial void spaces which penetrate the agglomerate. The agglomerates also possess a 4-250 micron particle size, 1-1000 m2/gm. surface area, and an Attrition Quality Index (AQI) of at least 10. The method comprises dry milling inorganic oxide particles, e.g. silica gel, wet milling the dry milled inorganic oxide particles (to preferably impart a colloidal segment of <1 micron particles), and spray drying the particles. The high AQI assures that the agglomerates are frangible and that polymerization performance is improved. The controlled morphology is believed to permit the constituent particles of the agglomerates to be more uniformly impregnated or coated with conventional olefin polymerization catalysts.

Abstract: A catalyst with a high sulphur tolerance for the hydrogenation of middle distillate aromatics which comprises as a support (a) an alumina, the surface of which has been modified by contacting it with a silicon-containing compound, or (b) a silica, the surface of which has been modified by contacting it with an aluminum-containing compound. The support has been treated with air, oxygen or water vapor at an elevated temperature in order to convert the said silicon-containing compound or the said aluminum-containing compound to oxide form. The hydrogenating component of the catalyst is one or more metals of the platinum group.

Abstract: Aluminum-magnesium silicate- or fluorinated magnesium silicate- aerogels which may be calcined, chemically modified, ion-exchanged, agglomerated, used as a component of a catalyst composition for an addition polymerization; supported versions thereof; and processes for polymerization are disclosed.

Abstract: The present invention relates to a hydrotreating catalyst composed of a carrier having a Brønsted acid content of at least 50 &mgr;mol/g such as a silica-alumina carrier or a silica-alumina-third component carrier, in which the silica is dispersed to high degree and a Brønsted acid content is at least 50 &mgr;mol/g, and at least one active component (A) selected from the elements of Group 8 of the Periodic Table and at least one active component (B) selected from the elements of Group 6 of the Periodic Table, supported on said carrier. The present invention also relates to a method for hydrotreating hydrocarbon oils using the same. The hydrotreating catalyst of the present invention provides excellent tolerance to the inhibiting effect of hydrogen sulfide, high desulfurization activity, and exhibits notable effects for deep desulfurization of hydrocarbon oils containing high contents of sulfur, in particular gas oil fractions containing difficult-to-remove sulfur compounds.

Abstract: A process is disclosed for producing hydrocarbons by contacting a feed stream comprising hydrogen and carbon monoxide with a catalyst in a reaction zone maintained at conversion-promoting conditions effective to produce an effluent stream comprising hydrocarbons. The process is characterized by using a catalyst prepared by a method involving (1) forming a catalyst gel by destabilizing an aqueous colloid comprising (a) at least one catalytic metal for Fischer-Tropsch reactions (e.g., iron, cobalt, nickel and/or ruthenium), (b) colloidal cerium oxide, zirconium oxide, titanium oxide and/or aluminum oxide, and optionally (c) Al(OR)3, Si(OR)4, Ti(OR)4 and/or Zr(OR)4 where each R is an alkyl group having from 1 to 6 carbon atoms; and (2) drying the gel.

Abstract: A process for the preparation of supported metallocene-alumoxane catalysts comprising the steps of: a) reacting a metallocene with an alumoxane at a temperature comprised between 15 and 50° C., b) recovering a mixture comprising an alkylmetallocenium cation and an anionic alumoxane oligomer, c) reacting said mixture with a support, and d) recovering a supported metallocene-alumoxane catalyst as a dry solid, the reaction with the support being carried out at a temperature comprised between 85° C. and 110° C., preferably between 90 and 130° C., and their use for the polymerization or copolymerization of olefins.

Abstract: Process for the preparation of a micro-mesoporous gel consisting of a silica matrix in which one or more metal oxides are possibly dispersed comprising: (a) subjecting to hydrolysis and gelification a tetra-alkylorthosilicate with an alkyl-trimethylammonium hydroxide having the formula R(CH3)3N—OH, wherein R is selected from n-butyl, n-pentyl, n-hexyl and n-heptyl, possibly in the presence of one or more metal compounds, the molar ratios in this mixture being: R—OH/SiO2=0-10; R(CH3)3N—OH/SiO2=0.05-0.4; H2O/SiO2=5-40; metal oxides/SiO2=0-0.02; whereas the ratio H2O/R(CH3)3N—OH varies according to the number of carbon atoms in the alkylic chain R as follows: R=n-butyl, H2O/R(CH3-)3N—OH<35; R=n-pentyl, H2O/R(CH3)3N—OH<70; R=n-hexyl, H2O/R(CH3)3N—OH<102; R=n-heptyl, H2O/R(CH3)3N—OH<136; (b) subjecting the gel or solid obtained in step (a) to drying and calcination.

Abstract: The invention is a selective reduction catalyst useful for converting exhaust gases generated by a diesel engine where the atmosphere is oxidizing. The catalyst comprises 5-40 wt. % silica of a silica/alumina sol-gel produced support carrying 0.25-4.0 wt. % platinum.