Abstract: Catalysts prepared by combining M--Al.sub.2 O.sub.4 where M is an element of Group Ib, VIIb or VIII of the Periodic Table of the Elements with tin, lead, an element of group IIa or IIb of the Periodic Table of the Elements as oxide or salt or in elemental form and calcining at 300-1300.degree. C. under 0.1-200 bar and the process for preparing them.

Abstract: A catalyst and a process for producing the catalyst are provided. For the catalytic reduction of NO.sub.x and for the oxidation of hydrocarbons, the catalyst contains a spinel containing the metals copper, zinc and aluminum.

Abstract: A catalyst and a process for producing the catalyst are provided. For the catalytic reduction of NO.sub.x and for the oxidation of hydrocarbons, the catalyst contains a spinel containing the metals copper, zinc and aluminum.

Abstract: A supported silver-containing catalyst for the decomposition of dinitrogen monoxide as pure gas or in admixture with other gases and having an aluminum oxide support which has a specific surface area of from 26 to 350 m.sup.2 /g, and a process for the selective catalytic decomposition of dinitrogen monoxide as pure gas or in admixture with other gases at elevated temperature, in which the said supported catalyst is used.

Abstract: A process for the catalytic decomposition of dinitrogen monoxide in a gas stream by contacting the gas stream at temperatures of 200.degree.-900.degree. C. and pressures of 0.1 to 20 bar with a catalyst free of noble metals, the catalyst being prepared by combining a spinel CuAl.sub.2 O.sub.3 with another spinel-forming metal component selected from the group consisting of tin, lead, zinc, magnesium, calcium, strontium and barium or mixtures thereof in elemental form or as an oxide or salt, and calcining at temperatures of 300.degree.-1300.degree. C. and under pressures of 0.1-200 bar in order to at least partially liberate the copper from the spinel by replacement with the other metal component.

Abstract: A process for the preparation of iron-, potassium- and cerium-containing catalysts for the dehydrogenation of hydrocarbons from the same spent catalysts (regeneration) by grinding and, if necessary, purifying the spent material, restoring the original activity by adjusting the composition and restoring the external shape comprises adding to the ground material an effective amount of potassium and such an amount of cerium that the total amount of cerium is greater than the amount originally present.

Abstract: A metal oxide-containing catalyst which also contains, besides oxides of titanium and/or zirconium, oxides of vanadium and/or niobium and oxides of molybdenum, tungsten, and/or chromium, sulfates of alkaline earth metals, and which is used in a process for the degenerative oxidation of organic compounds present in exhaust gases from combustion plants.