Abstract: The present invention provides a coating composition for substrates. The coating composition of the present invention generally includes a silicate binder and a plurality of photocatalytic particles. The silicate binder functions as a bonding agent to establish the coating on the substrate. A plurality of photocatalyst particles are dispersed throughout the silicate binder. The particles are included in an amount that provides sufficient distribution of the particles in the resulting coating. The incorporation of the present invention onto substrates prevents algal growth on building materials utilizing the coated substrates.

Abstract: A method and system for the in situ synthesis of a combinatorial library including impregnating a first component with a second component. The method and system advantageously may be employed in the synthesis of materials for screening for usefulness as a catalyst.

Abstract: The invention provides a noble metal-containing supported catalyst which contains one of the noble metals from the group Au, Ag, Pt, Pd, Rh, Ru, Ir, Os or alloys of one or more of these noble metals in the form of noble metal particles on a powdered support material. The particles deposited on the support material have a degree of crystallinity, determined by X-ray diffraction, of more than 2 and an average particle size between 2 and 10 nm. The high crystallinity and the small particle size of the noble metal particles lead to high catalytic activity for the catalyst. It is particularly suitable for use in fuel cells and for the treatment of exhaust gases from internal combustion engines.

Abstract: A catalyst (5) for selectively oxidizing carbon monoxide, wherein a noble metal (3) and an active oxygen supply material (4) capable of oxidizing carbon monoxide are supported on a substrate (6). Favorable selective oxidation of carbon monoxide can be obtained by setting the distance between the noble metal (3) and the active oxygen supply material (4) such that the noble metal (3) is close enough to accept active oxygen from the active oxygen supply material (4), and preferably within 0.1 mm. This catalyst (5) for selectively oxidizing carbon monoxide is effective at removing carbon monoxide from a reformate gas whose main component is hydrogen and which is supplied to a fuel cell.

Abstract: A cobalt based Fischer-Tropsch catalyst which including a porous catalyst support and metallic cobalt crystallites within the support. The catalyst has a proportion of its cobalt in reducible form, with this proportion being expressible as &OHgr; mass %, based on the total pre-reduction catalyst mass. The catalyst also has, when freshly reduced, a mono-modal Gaussian metallic cobalt crystallite size distribution, a metallic cobalt surface area, in m2 per gram of catalyst, of from 0.14 &OHgr; to 1.03 &OHgr;, and a catalyst geometry that ensures a stabilized Fischer-Tropsch synthesis effectiveness factor of 0.9 or greater.

Abstract: The invention is directed towards a process for the epoxidation of olefins, using molecular oxygen and hydrogen, characterized in that, as catalyst, a compound comprising gold, preferably in nanometer size, on a support material, in which the support material is comprised of Scandium, Yttrium, Lanthanide, Zirconium, Hafnium, Vanadium, Niobium, Tantalum, Chromium, Molybdenum and/or Tungsten and is essentially free of titanium is applied, and a compound comprising gold, preferably in nanometer size, on a support material, in which the support material is comprised of Scandium, Yttrium, Lanthanide, Zirconium, Hafnium, Vanadium, Niobium, Tantalum, Chromium, Molybdenum and/or Tungsten and is essentially free of titanium, a process for the preparation of said compounds and a method of catalyzing a chemical reaction through conducting said chemical reaction in the presence of said compound.

Abstract: Moldings based on 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 oxides selected from the group SiO2, Al2O3, TiO 2 and ZrO2 in any desired combination but with the exception of SiO2/Al2O3 mixed oxides, in which > 75 wt. % of SiO2 is present. Other constituents <1 wt. % Bulk density 250-1500 g/l, are produced by homogenizing pyrogenically produced mixed oxide as desired with one or more compounds from the group methylcellulose, methylhydroxyethylcellulose, wax, polyethylene glycol, magnesium stearate and/or aluminium stearate with addition of water, drying the product at a temperature of 70-150° C.

Abstract: An oxidative halogenation process involving contacting a hydrocarbon, for example, ethylene, or a halogenated hydrocarbon with a source of halogen, such as hydrogen chloride, and a source of oxygen in the presence of a catalyst so as to form a halocarbon, preferably a chlorocarbon, having a greater number of halogen substituents than the starting hydrocarbon or halogenated hydrocarbon, for example, 1,2-dichloroethane. The catalyst is a novel composition comprising copper dispersed on a porous rare earth halide support, preferably, a porous rare earth chloride support. A catalyst precursor composition comprising copper dispersed on a porous rare earth oxyhalide support is disclosed. Use of the porous rare earth halide and oxyhalide as support materials for catalytic components is disclosed.

Abstract: An adsorbent catalyst for reducing the amounts of nitrogen oxides, hydrocarbons and carbon monoxide contained in exhaust or combustion gases, which catalyst adsorbs nitrogen oxides, when the exhaust or combustion gases contain in excess of oxygen, and liberates and reduces the adsorbed nitrogen oxides, when the gases contain oxygen in stoichiometric amounts or less, which adsorbent catalyst include a porous support material the surface area of which is large and which contains at least the following: a first catalytic metal, which is preferably Pt, a first NOx adsorbent, which preferably contains at least one of the following metals: Ba and Sr, a second NOx adsorbent, which preferably contains at least one of the following metals: La and Y, and a redox NOx adsorbent, which preferably contains at least one of the following metals: Ce, Zr, Ti, Nb, Mn, Pr, Nd, Sm, Eu and G.

Abstract: A catalyst for purification of exhaust gas includes a carrier, and a catalyst layer containing an alkali metal and/or an alkaline earth metal as an NOx-adsorbing component, the catalyst layer being loaded on the carrier, in which catalyst the carrier-composing material contains Si in an amount of 0.5 to 10.0% by weight as expressed as an oxide. Since the inclusion of Si can suppress the deterioration of the carrier caused by the alkali metal and/or the alkaline earth metal during the use of the catalyst, the catalyst can be used over a long period.

Abstract: A carrier which permits preparation of a catalyst possessed of excellent catalytic performance and used for the production of ethylene oxide, a catalyst obtained by using this carrier, endowed with excellent catalytic performance, and used for the production of ethylene oxide, and a method for the production of ethylene oxide by the use of the catalyst are provided. The carrier is obtained by mixing &agr;-alumina having an alkali metal content in the range of 1-70 m.mols/kg (&agr;-alumina) with an aluminum compound, a silicon compound, and an alkali metal compound and calcining the produced mixture. The carrier which has an aluminum content as reduced to Al in the range of 0-3 mols/kg of carrier, a silicon compound content as reduced to Si in the range of 0.01-2 mols/kg of carrier, and an alkali metal content as reduced to alkali metal in the range of 0.01-2 mols/kg of carrier is used for the deposition of a catalyst for use in the production of ethylene oxide.

Abstract: It is an object of the present invention to provide an exhaust gas purifying catalyst formed as a single catalyst that has a great deal of flexibility when being assembled into an exhaust system and that is capable of executing both an NOx absorbing function and a three-way function in a desired manner. To attain the this object, an absorbent catalyst layer to which an absorbent agent such as potassium and an acid material such as zeolite are added, an absorbent agent block layer formed of zeolite, and a three-way catalyst layer to which an acid material such as phosphorus is added are bonded together on a cordierite carrier. The acid material in the absorbent catalyst layer and the absorbent agent block layer inhibit the movement of the absorbent agent to the three-way catalyst layer, and transform the absorbent agent into harmless and stable potassium phosphate even if the absorbent agent reaches the three-way catalyst.

Abstract: A method for uniformly dispersing noble metal particles on a porous carrier by first mixing an alkoxide product of aluminum or silicon and a noble metal precursor together; then mixing a surfactant into the mixture; then mixing ammonia solution into the mixture to form a hydroxide of aluminum or silicon; then mixing a reducing agent into the mixture to convert the noble metal precursor into noble metal nanoparticles dispersed on the hydroxide; then separating the noble metal nanoparticles and the hydroxide from the mixture before calcining the hydroxide into an oxide of aluminum or silicon.

Abstract: The invention concerns a catalyst carrier comprising a fibre paper impregnated with a slurry comprising silica sol, micro fibres and a filler, wherein said micro fibres have an equivalent average particle size, measured with sedigraph method, from about 200 nm to about 30000 nm and said filler has an average equivalent particle size, measured with sedigraph method, from about 300 to about 10000 nm. The invention further concerns a method of its preparation, a slurry useful therefore, a catalyst comprising such a catalyst carrier and use of the catalyst.

Abstract: The present invention relates to a layered catalyst composite useful for reducing contaminants in exhaust gas streams, especially gaseous streams containing sulfur oxide contaminants. More specifically, the present invention is concerned with improved catalysts of the type generally referred to as “three-way conversion” catalysts. The layered catalysts trap sulfur oxide contaminants which tend to poison three-way conversion catalysts used to abate other pollutants in the stream. The layered catalyst composites of the present invention have a sulfur oxide absorbing layer before or above a nitrogen oxide absorbing layer. The layered catalyst composite comprises a first layer and a second layer. The first layer comprises a first support and at least one first platinum component. The second layer comprises a second support and a SOx sorbent component, wherein the SOx sorbent component is selected from the group consisting of MgAl2O4, MnO, MnO2, and Li2O.

Abstract: The present invention provides hydro-oxidation catalysts for the oxidation of hydrocarbons, containing an organic-inorganic hybrid material as well as gold particles and/or silver particles, a process for the production thereof, and the use thereof as a catalyst.

Abstract: A silica-based photocatalyst fiber having visible-light activity, which fiber comprises a composite oxide phase comprising an oxide phase (first phase) mainly made of a silica component and a titania phase (second phase), wherein the second phase contains a metal element other than titanium and the existent ratio of the second phase slopingly increases towards the surface of the fiber, and a process for the production thereof.

Abstract: A substrate includes a non-conductive portion to be electroless-plated of a substrate, on the surface of which fine metal catalyst particles composed of silver nuclei and palladium nuclei each having an average particle size of 1 nm or less adhere at a high nuclei density of 2000 nuclei/&mgr;m2 or more. The metal catalyst particles are produced by sensitizing the non-conductive portion of the substrate by dipping the substrate in a sensitizing solution containing bivalent tin ions, activating the non-conductive portion of the substrate by dipping the substrate in a first activator containing silver ions, and activating the non-conductive portion of the substrate by dipping the substrate in a second activator containing palladium ions.

Abstract: The disclosure is directed to a process for preparing an oxidic catalyst comprising copper in an oxidation state >0, which comprises treating a solid oxidic support material with an aqueous solution comprising at least one copper salt and at least one organic water soluble polymer which binds copper ions coordinatively in a concentration of from 0.1 to 100 g/l and then calcining, to the catalyst obtainable by this process and also to a process for dehydrogenating secondary alcohols to ketones using the catalysts, especially for dehydrogenating cyclohexanol.

Abstract: A lean NOx catalyst and method of preparing the same is disclosed. The lean NOx catalyst includes a ceramic substrate, an oxide support material, preferably &ggr;-alumina, deposited on the substrate and a metal promoter or dopant introduced into the oxide support material. The metal promoters or dopants are selected from the group consisting of indium, gallium, tin, silver, germanium, gold, nickel, cobalt, copper, iron, manganese, molybdenum, chromium, cerium, vanadium, oxides thereof, and combinations thereof. The &ggr;-alumina preferably has a pore volume of from about 0.5 to about 2.0 cc/g; a surface area of between about 80 to 350 m2/g; an average pore size diameter of between about 3 to 30 nm; and an impurity level of less than or equal to 0.2 weight percent. In a preferred embodiment the &ggr;-alumina is prepared by a sol-gel method, with the metal doping of the &ggr;-alumina preferably accomplished using an incipient wetness impregnation technique.

Abstract: The present invention relates to the continuous production of nano-scale precious metal particles on SiH-containing support materials, the compositions themselves, and the use of these precious metal-containing compositions as catalyst. The continuous process according to the invention includes impregnating support materials and, after thermal activation, drying the support materials by spraying or by fluidized bed technology leads to form precious metal-containing support compositions that are active in the catalysis of oxidation reactions. The catalytically active precious metal-containing support compositions exhibit high selectivities and productivities and have very long catalyst service lives without deactivation. The invention also relates to a process for the oxidation of hydrocarbons in the presence of oxygen, a reducing agent and the precious-metal containing support compositions of the present invention.

Abstract: This catalyst for purifying exhaust gases can suppress an active ingredient, such as an alkali metal, which reacts with a substrate from moving to the substrate, thereby preventing a decrease in strength such as thermal shock resistance of the substrate. In production, first, a first oxide layer composed mainly of an oxide which has a high reactability with the active ingredient is formed on the substrate. Next, a second oxide layer composed mainly of an oxide which has a low reactability with the active ingredient is formed on the first oxide layer. Then, a catalyst layer loaded at least with a noble metal and the active ingredient is formed on the second oxide layer. This second oxide layer suppresses transfer of the active ingredient and some active ingredient which has passed through the second oxide layer is caught by the first oxide layer owing to its reaction.

Abstract: A gel composition substantially contained within the pores of a solid material for use as a catalyst or as a catalyst support in dehydrogenation and dehydrocyclization processes.

Abstract: A sorbent composition is provided which can be used in the desulfurization of a hydrocarbon-containing fluid such as cracked gasoline or diesel fuel. The sorbent composition contains a support component and a promoter component with the promoter component being present as a skin on the support component. Such sorbent composition is prepared by a process of impregnating a support component with a promoter component, wherein the promoter component has been melted under a melting condition, followed by drying, calcining, and reducing to thereby provide the sorbent composition.

Abstract: Compositions for reduction of gas phase reduced nitrogen species and NOx generated during a partial or incomplete combustion catalytic cracking process, preferably, a fluid catalytic cracking process, are disclosed. The compositions comprise (i) an acidic metal oxide containing substantially no zeolite, (ii) an alkali metal, alkaline earth metal, and mixtures thereof, (iii) an oxygen storage component, and (iv) a noble metal component, preferably rhodium or iridium, and mixtures thereof, are disclosed. Preferably, the compositions are used as separate additives particles circulated along with the circulating FCC catalyst inventory. Reduced emissions of gas phase reduced nitrogen species and NOx in an effluent off gas of a partial or incomplete combustion FCC regenerator provide for an overall NOx reduction as the effluent gas stream is passed from the FCC regenerator to a CO boiler, whereby as CO is oxidized to CO2 a lesser amount of the reduced nitrogen species is oxidized to NOx.

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.

Abstract: The selectivity and activity of a silver-based olefin epoxidation catalyst is found to be a function of the pore size distribution in the alumina carrier on which it is deposited. Specifically it is found advantageous to provide a carrier which has a minimum of very large pores, (greater than 10 micrometers) and a water absorption of 35 to 55% and a surface area of at least 1.0 m2/g. A method of making such carriers is also described.

Abstract: A catalyst which comprises a carrier and silver deposited on the carrier, which carrier has a surface area of at least 1 m2/g, and a pore size distribution such that pores with diameters in the range of from 0.2 to 10 &mgr;m represent at least 70% of the total pore volume and such pores together provide a pore volume of at least 0.

Abstract: The present invention provides hydro-oxidation catalysts for the oxidation of hydrocarbons, containing an organic-inorganic hybrid material as well as gold particles and/or silver particles, a process for the production thereof, and the use thereof as a catalyst.

Abstract: The present invention teaches a method for increasing the cobalt surface area per gram of catalyst in a cobalt Fischer-Tropsch catalyst, supported on a silica-based carrier material, by using cobalt amine carbonate precursors. A Fischer-Tropsch catalyst preferably includes a catalytically active first metal containing cobalt, and a carrier material containing silica or a silica compound with a cobalt surface area greater than 13 m2/g catalyst. The catalyst active in the FT reaction has a minimum alpha value of 0.87 and a CO conversion of 24 wt % or more. In accordance with another preferred embodiment, a process for producing a Fischer-Tropsch catalyst includes saturating silica or silica compounds with a solution of cobalt amine carbonate, removing the excess solution by filtration, heating the resulting product in order to allow cobalt hydroxycarbonate to precipitate, and drying and calcining the resulting product. Optionally the calcined product is reduced.

Abstract: A silica-rich support is developed, which is used for preparing catalysts and may be employed in other fields of engineering: for producing fiber optic materials, in the manufacture of filters, etc.

Abstract: A method for making a silica supported catalyst involves impregnating a silica component with a catalytic metal using an aqueous, alkaline bath before drying. More specifically, the method involves forming and washing a silica component, such as a silica gel or a co-gel, for example a silica-zirconia co-gel. Then, the washed silica component is contacted with the alkaline bath to effect the impregnation with the catalytic metal, such as cesium, to form an activated silica component. Subsequently, the activated silica component is dried to form the catalyst. The resulting catalysts demonstrate good mechanical strength.

Abstract: The production of ethylenically unsaturated acids or esters by the catalytic reaction of an alkanoic acid or ester, especially methyl propionate, with formaldehyde, and a catalyst therefor wherein the catalyst comprises a porous high surface area silica containing 1-10% by weight of an alkali metal, especially cesium, (expressed as metal) and having compounds of at least one modifier element selected from boron, magnesium, aluminum, zirconium and hafnium dispersed in the pores of said silica in such amount that the catalyst contains a total of 0.25 to 2 gram atoms of primary modifier element per 100 moles of silica.

Abstract: A silica-group composite oxide fiber formed of a composite oxide phase of an oxide phase (first phase) mainly made of a silica component and a metal oxide phase (second phase) excluding silica, in which the existent ratio of at least one metal element of a metal oxide constituting the second phase upward slopingly increases toward the surface layer of the fiber and a process for the production thereof.

Abstract: It is an object of the present invention to provide a catalyst for manufacturing a carboxylic ester, which has superior catalytic activity. The present invention relates to a catalyst for preparing a carboxylic ester, used in a) a reaction for preparing a carboxylic ester by reacting oxygen, an aldehyde, and an alcohol, or b) a reaction for manufacturing a carboxylic ester by reacting oxygen and one or more types of alcohol, comprising a carrier and 1) ultrafine gold particles and/or 2) ultrafine metal particles containing gold and a second element other than gold, having an average particle diameter of not more than 6 nm, are supported on the carrier.

Abstract: Scaly silica particles having a laminated structure, consisting essentially of secondary particles of foliar silica, each formed by a plurality of flaky primary particles of scaly silica which are overlaid one on another and aligned face-to-face in parallel with one another, said secondary particles being present independent of one another.

Abstract: A process and catalyst for the direct oxidation of an olefin having three or more carbon atoms, such as propylene, by oxygen to the corresponding olefin oxide, such as propylene oxide. The process involves contacting the olefin with oxygen under reaction conditions in the presence of hydrogen and in the presence of a catalyst. The catalyst comprises gold on a titanosilicate, preferably a microporous or mesoporous titanosilicate, such as, TS-1, TS-2, Ti-beta, Ti-ZSM-48, or Ti-MCM-41. Selectivity to the olefin oxide is high at good conversions of the olefin. The catalyst is readily regenerated, and the time between catalyst regenerations is long.

Abstract: The present invention includes a sol-gel supported catalyst for the dehydrogenation of lower alkanes, the catalyst comprising at least one active metal and at least one promoter metal attached to a sol-gel mixed oxide support. The sol-gel mixed oxide support arises from the polymerization of at least one precursor. The active metal and the promoter metal have been attached to the sol-gel mixed oxide support by the active metal and the promoter metal having been co-precipitated with the precursor of the sol-gel mixed oxide support. The invention also includes a method of making the above mentioned catalyst and a method of using the catalyst to dehydrogenate lower alkanes to produce lower alkenes.

Abstract: A material especially useful for the selective oxidation of hydrocarbons and other organic compounds includes a non-crystalline, porous inorganic oxide having at least 97 volume percent mesopores based on micropores and mesopores, and at least one catalytically active metal selected from the group consisting of one or more transition metal and one or more noble metal.

Abstract: A solid supported catalyst suitable for the vapor phase carbonylation of lower aliphatic alcohols, ethers, ester, and ester-alcohol mixtures, and desirably, methanol, to produce carboxylic acid, esters and mixtures thereof. The solid supported catalyst includes an effective amount of gold associated with a solid support material in the presence of a halide promoter. Desirably, the support material is selected from carbon, activated carbon, pumice, alumina, silica, silica-alumina, magnesia, diatomaceous earth, bauxite, titania, zirconia, clay, magnesium silicate, silicon carbide, zeolites, ceramics and combinations thereof.

Abstract: An exhaust gas emission purifying catalyst has a catalyst layer (20) supported on a carrier (10). The catalyst layer includes a composite oxide, in which noble metals and occluding agents are mixed in order to inhibit the movement of the occluding agents even at high temperatures and to prevent deterioration of the purifying performance of the catalyst after operation at a high temperature. The composite oxide is comprised of silicon (Si) and at least one of cobalt (Co), zirconium (Zr), iron (Fe), and manganese (Mn).

Abstract: An olefin oxidation catalyst comprising a carrier, and silver and an alkali metal supported thereon, wherein the content of organic substances is less than 0.1 wt %.

Abstract: A composite gel or aerogel is formed by commingling a particulate guest (such as a colloidal or dispersed (i.e., non-colloidal) solid or a powder) with a sol which is either about to gel or in which gelation has just started. After addition of the particulate, the mixture is then permitted to gel into a solid, gelled composite with open pores. This solid, gelled composite is then dried in a manner that prevents the collapse of open pores within the solid, gelled composite in which the gel acts as a “nanoglue” that holds the particles together.

Abstract: The subject of the invention is a process for treating a “permeable” architectural material by impregnation, comprising the spraying onto the architectural material to be treated of one or more liquid-phase dispersions of at least one type of photocatalytic compounds based on metal oxide or sulphide and of at least one type of compound for promoting the adhesion of the said photocatalytic compounds to the said architectural material.

Abstract: The present invention relates to an initiation system composed of the reaction product of at least one cyclic siloxane and at least one organometalic compound of sufficient reactivity to open the siloxane ring. Application of the present invention is to the preparation of homopolymers of (meth)acrylic, vinylaromatic or diene monomers, random or block copolymers of these monomers and, in particular, application to poly(methylmethacrylate) with a high content of isotactic triads.

Abstract: A catalyst composition represented by the following empirical formula which is useful in production of unsaturated nitrites by ammoxidation: Mo10BiaFebSbcNidCreFfGgHhKkXxYyOi(SiO2)j wherein F represents at least one element selected from the group consisting of zirconium, lanthanum and cerium, G represents at least one element selected from the group consisting of magnesium, cobalt, manganese and zinc, H represents at least one element selected from the group consisting of vanadium, niobium, tantalum and tungsten, x represents at least one element selected from the group consisting of phosphorus, boron, and tellurium, Y represents at least one element selected from the group consisting of lithium, sodium, rubidium and cesium, the suffixes a-k, x and y represent a ratio of atoms or atomic groups, and a=0.1-3, b=0.3-15, c=0-20, d=3-8, e=0.2-2, f=0.05-1, e/f>1, g=0-5, h=0-3, k=0.

Abstract: A carrier which permits preparation of a catalyst possessed of excellent catalytic performance and used for the production of ethylene oxide, a catalyst obtained by using this carrier, endowed with excellent catalytic performance, and used for the production of ethylene oxide, and a method for the production of ethylene oxide by the use of the catalyst are provided. The carrier is obtained by mixing &agr;-alumina having an alkali metal content in the range of 1-70 m.mols/kg (&agr;-alumina) with an aluminum compound, a silicon compound, and an alkali metal compound and calcining the produced mixture. The carrier which has an aluminum content as reduced to Al in the range of 0-3 mols/kg of carrier, a silicon compound content as reduced to Si in the range of 0.01-2 mols/kg of carrier, and an alkali metal content as reduced to alkali metal in the range of 0.01-2 mols/kg of carrier is used for the deposition of a catalyst for use in the production of ethylene oxide.

Abstract: The invention concerns a catalyst comprising at least one group VIII metal, at least one additional metal, at least two halogens, including chlorine and fluorine, and at least one amorphous oxide matrix. The catalytic composition is such that the fluorine content is 1.5% by weight or more of the total catalyst mass. The invention also concerns the use of this catalyst in hydrogenating aromatic compounds contained in feeds comprising sulphurated compounds.

Abstract: The present invention relates to a new fluidized-bed catalyst used in a process of propylene ammoxidation to acrylonitrile. The catalyst comprises a silica as carrier and a composition represented by the following general formulas: AaBbCcGedNaeFefBigMohOx Wherein A represents at least one element selected from a group consisting Li,K,Rb,Cs,Sm, In or Tl; B represents at least one element selected from a group consisting of P, Sb, Cr, W. Pr, Ce, As, B, Te, Ga, Al, Nb, Th, La or V; C represents one element selected from a group consisting of Ni, Co, Sr, Mn, Mg, Ca, Zn, Cd or Cu and the mixture thereof; a is a number of from 0.01 to 1.5; b is a number of from 0.01 to 3.0; c is a number of from 0.1 to 12.0; preferably from 2 to 10; d is a number of from 0.01 to 2.0; preferably from 0.01 to 1.0; e is a number of from 0.01 to 0.7; preferably from 0.05 to 0.5; f is a number of from 0.1 to 8; preferably from 1.0 to 3.0; g is a number of from 0.01 to 6; preferably from 0.1 to 2.

Abstract: A shell impregnated catalyst of Pd—Au produced on a silica support to have a Pd loading of 1.8 g/L of catalyst to about 7.2 g/L and a Au to Pd weight ratio of 0.3 to 2.0 by impregnating the support with aqueous solutions of palladium and gold salts or acids and thereafter precipitating water insoluble compounds of Pd and Au on the with alkali metal silicate or hydroxide solutions, then dried, and the surface precipitated compounds of Pd and Au are then reduced by reaction with ethylene or hydrogen at a temperature of greater than 150° C. up to 310° C. or with hydrogen up to 299° C. until substantially all of the Pd and Au contents are reduced to a free metal state, after which the support is impregnated with potassium acetate to an extent of 6 to 7 weight percent of the weight of the total catalyst.