Abstract: Manufacture of catalysts containing at least four essential metals: copper, zinc, aluminum and at least one metal selected from the group formed of rare earths and zirconium.The process comprises the formation of a crystallized precipitate of the above-mentioned metals by intimate mixture of a crystallized precipitate of copper, zinc and aluminum, containing less than 0.06% by weight of sodium after washing, with a precipitate of at least one metal of the rare earths group and/or zirconium, containing less than 3% of nitrogen after washing.The catalysts are used in balanced reactions involving alcohols and synthesis gases, and particularly for methanol synthesis.

Abstract: There are described catalysts containing, as oxides, iron, chromium and potassium, the latter being optionally partly in form of kaliophyllite Al.sub.2 O.sub.3, 2 SiO.sub.2, K.sub.2 O, as well as lanthanum, in a proportion, calculated in oxide weight, of 1-15% with respect to the final catalyst.The presence in the catalyst of lanthanum oxide, optionally previously combined with cobalt or vanadium, at least in part in the form of a mixed oxide of the perovskite type, confers to the catalyst an improved activity and/or selectivity in dehydrogenation reactions, particularly of ethylbenzene to styrene.

Abstract: A process for manufacturing catalysts containing, as oxides, iron, chromium, potassium, as well as a rare earth metal in a proportion, calculated in oxide weight, of 1-15% with respect to the final catalyst, comprises:a first step, wherein a product is prepared by a reaction between compounds of rare earth metal(s) and of another metal selected from Fe, Cr, Co, Al or V, and a calcination; anda second step wherein a mixture is formed between the product resulting from the first step, the other necessary reactants and water; the resulting paste is dried after optional shaping and calcined. A clayish material can be used in the step.The catalysts obtained present an improved efficiency in dehydrogenation reactions, particularly of ethylbenzene to styrene.

Abstract: Catalyst for dealkylating, in the presence of steam, a hydrocarbon charge, obtained for example from a catalytic reforming unit or from a unit for the production of aromatic hydrocarbons, and containing at least one alkylaromatic hydrocarbon such as toluene or a xylene, said catalyst containing an alumina carrier of a specific surface higher than 50 m.sup.2 /g and, by weight with respect to the catalyst, from 0.1 to 2% of rhodium, from 0.05 to 2% of at least one metal selected from copper, silver and gold, from 0.05 to 2% of rhenium and from 0.02 to 5% of at least one additional metal selected from lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium and uranium.

Abstract: A pollution control catalyst for a catalytic converter comprising the exhaust system of an internal combustion engine, said catalyst including a refractory oxide support, and an activated phase therefor comprised of 0.3 to 7% by weight cerium based upon the weight of said support, 0.1 to 3.5% by weight iron, also based upon the weight of said support, at least one platinum or palladium metal, and at least one iridium or rhodium metal.

Abstract: Catalyst for dealkylating, in the presence of steam, a hydrocarbon charge, obtained for example from a catalytic reforming unit or from a unit for the production of aromatic hydrocarbons, and containing at least one alkylaromatic hydrocarbon such as toluene or a xylene, said catalyst containing an alumina carrier of a specific surface higher than 50 m.sup.2 /g and, by weight with respect to the catalyst, from 0.1 to 2% of rhodium, from 0.05 to 2% of at least one metal selected from copper, silver and gold, from 0.05 to 2% of rhenium and from 0.02 to 5% of at least one additional metal selected from lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium and uranium.

Abstract: A gas containing carbon oxysulfide or carbon disulfide is passed in admixture with oxygen through a catalyst formed of a carrier, vanadium oxide and silver, the proportion of iron oxide, if any, being lower than 1% by weight. The amount of vanadium oxide may be 0.5 to 10% by weight and that of silver 0.05 to 4% by weight.

Abstract: A catalyst for the steam dealkylation of aromatic hydrocarbons, comprising a carrier and 3 metals, is regenerated in the reaction zone containing the catalyst bed, after disconnection of said zone from the producing unit, by proceeding to the successive steps of: scavenging said zone with hydrogen and then with an inert gas, progressively replacing said inert gas by a gas containing molecular oxygen, burning the catalyst at a temperature lower than 650.degree. C. so as to calcine the carbon deposits of the catalyst, passing through the catalyst bed an air stream containing halogen to increase the halogen content of the catalyst, calcining by means of an air stream at a temperature of 300.degree.-600.degree. C. and purging with an inert gas before reconnecting said reaction zone to the producing unit.

Abstract: Catalyst for producing hydrogen by reaction of carbon monoxide with water or for producing methanol by reaction of carbon monoxide with hydrogen, containing by weight 10-60% of copper oxide, 5-40% of zinc oxide, 1-20% of a rare earth metal oxide, 30-70% of aluminous cement and optionally 0.01-1% of a noble metal from group VIII.

Abstract: Catalytic process for steam dealkylation of a charge containing at least one alkyl aromatic hydrocarbon, such as a charge issued from effluents of units for catalytic reforming or for producing aromatic hydrocarbons, wherein the catalyst contains an alumina carrier, from 0.1 to 1% of rhodium, from 0.05 to 1% of TiO.sub.2 and optionally from 0.1 to 1% of ruthenium, palladium, iridium, platinum or osmium and/or from 0.01 to 5% of lithium, sodium, potassium, rubidium or cesium.

Abstract: Process for steam dealkylation of alkylaromatic hydrocarbons, particularly useful to produce benzene from toluene and to de-alkylate the alkylaromatic hydrocarbons contained in the effluents from catalytic reforming and aromatic production units, wherein the catalyst contains, in addition to an alumina carrier (a) at least one metal selected from ruthenium, rhodium, palladium, osmium, iridium and platinum (b) rhenium and (c) an alkali metal selected from lithium, sodium, potassium, rubidium and cesium.

Abstract: Alkylaromatic hydrocarbons are steam-dealkylated in the presence of a catalyst comprising an alumina carrier and 0.1 to 2% b.w. of a group VIII noble metal, 0.05 to 2% of a group I.sub.B metal and 0.01 to 5% of an alkali metal.

Abstract: Sulfur and sulfur compounds contained in a gas are oxidized in contact with a catalyst comprising vanadium oxide, iron oxide and alumina, said catalyst having a surface higher than 30 m.sup.2 /g and being obtained by impregnation of aluminum with soluble vanadium and iron compounds.

Abstract: Sulfur and oxidizable sulfur compound are oxidized in gas phase in the presence of a catalyst comprising vanadium oxide, iron oxide and aluminous cement. Silver and titanium oxide may also be present.

Abstract: An amorphous solid gel containing molybdenum and iron contains (a) ions of a ferric salt and ions from at least one salt containing, as simple cations, a metal M, in an atomic ratio M/ (Fe+M) from 0 to 0.5:1 (b) ions from a molybdic compound and ions from at least one salt containing, as oxygenated ions, a metal N, in an atomic ration N/ (Mo+N) from 0 to 0.5:1; and (c) water, wherein M is Co, Ni, Mn, Cr, Sc, Y or a rare earth metal, N is Cr, W, Mn, or V and (Mo+N) / (Fe+M) is 0.4:1 to 5:1.

Abstract: Catalyst for dehydrogenating hydrocarbons, as manufactured by the process comprising:Admixing one or more iron compounds, chromium compounds and potassium compounds, in a definite range of relative proportions,Moistening and malaxing the resulting mixture while adding thereto a clayish material in such an amount as to obtain by reaction with the potassium compound, a proportion of 3 to 55% b.w. of potassium alumino-silicate in the final catalyst,Shaping the homogeneized resulting paste, drying and roasting it at about 870 - 1050.degree. C, the potassium compound being used in an amount greater than that liable to combine with the clayish material.

Abstract: Catalyst for the conversion of carbon monoxide in the presence of water, to produce hydrogen, or in the presence of hydrogen, to produce methanol, said catalyst containing 10 - 60% by weight of copper oxide, 5 - 40% by weight of zinc oxide and 30 - 70% by weight of aluminous cement, the total content of copper oxide and zinc oxide being from 30 to 70% by weight.

Abstract: A process for purifying a hydrogen sulfide containing gas, which comprises absorbing said hydrogen sulfide onto a mass comprising zinc oxide, alumina and a group II A metal oxide, a large proportion of the group II A metal oxide being in the form of aluminate or silicoaluminate; then regenerating the mass by passing an oxygen containing gas therethrough.

Abstract: Process for purifying a gas containing hydrogen sulfide and sulfur dioxide, comprising substantially removing sulfur dioxide, absorbing hydrogen sulfide on a solid contact mass, intermittently regenerating said mass by means of an oxygen-containing gas, so as to produce a gas containing sulfur dioxide, and reacting the latter gas with hydrogen sulfide to produce sulfur.

Abstract: Catalyst for the decomposition of nitrogen oxides, particularly for use in catalytic exhaust boxes in view of decomposing the nitrogen oxides contained in the exhaust gases from internal combustion engines, comprising, deposited on a carrier, from 3 to 20% of an active phase of the formula Ni.sub.x (Fe.sub.y Cr.sub.z)O.sub.t, in which x has a value from 0.5 to 1.5, y + z a value from 1.5 to 3, the ratio ##EQU1## A VALUE FROM 0.01 TO 0.9 AND T A VALUE LOWER THAN 10.