Abstract: Iron- and manganese-containing heterogeneous catalyst, and a process for producing it, including the following steps: thermal decomposition of gaseous iron pentacarbonyl to give carbonyl iron powder having spherical primary particles; treatment of carbonyl iron powder with hydrogen, resulting in the metallic spherical primary particles at least partly agglomerating; surface oxidation of the iron particles to form iron oxide; contacting the particles with an aqueous solution of a manganese compound; drying in the presence of oxygen and subsequent calcination in the absence of oxygen, resulting in oxygen-comprising manganese compounds on the particles; and finally reaction of these with the iron oxide to form a mixed oxide of the formula MnxFe3-xO4, where 0<x?2. Process for preparing olefins by reacting carbon monoxide with hydrogen in the presence of a catalyst, wherein the abovementioned iron- and manganese-comprising heterogeneous catalyst is used as catalyst.

Abstract: Iron- and copper-containing heterogeneous catalyst, and a process for producing it, including the following steps: thermal decomposition of gaseous iron pentacarbonyl to give carbonyl iron powder having spherical primary particles; treatment of carbonyl iron powder with hydrogen, resulting in the metallic spherical primary particles at least partly agglomerating; surface oxidation of the iron particles to form iron oxide; contacting the particles with an aqueous solution of a copper compound; drying in the presence of oxygen and subsequent calcination in the absence of oxygen, resulting in oxygen-comprising copper compounds on the particles; and finally reaction of these with the iron oxide to form a mixed oxide of the formula CuxFe3-xO4, where 0<x?1. Process for preparing olefins by reacting carbon monoxide with hydrogen in the presence of a catalyst, wherein the abovementioned iron- and copper-comprising heterogeneous catalyst is used as catalyst.

Abstract: Iron- and copper-comprising heterogeneous catalyst and process for producing it, which comprises the following steps: I. thermal decomposition of gaseous iron pentacarbonyl to give carbonyl iron powder having spherical primary particles, II. treatment of carbonyl iron powder obtained in step I with hydrogen, resulting in the metallic spherical primary particles at least partly agglomerating, III. surface oxidation of the iron particles from step II (agglomerates=secondary particles, and also any primary particles still present) to form iron oxide, IV. contacting of the particles from step III with an aqueous solution of a copper compound, V. drying in the presence of oxygen and subsequent calcination in the absence of oxygen, resulting firstly in oxygen-comprising copper compounds on the particles and finally reaction of these with the iron oxide to form a mixed oxide of the formula CuxFe3-xO4, where 0<x?1.

Abstract: Iron- and manganese-comprising heterogeneous catalyst and process for producing it, which comprises the following steps: I. thermal decomposition of gaseous iron pentacarbonyl to give carbonyl iron powder having spherical primary particles, II. treatment of carbonyl iron powder obtained in step I with hydrogen, resulting in the metallic spherical primary particles at least partly agglomerating, III. surface oxidation of the iron particles from step II (i.e. agglomerates=secondary particles, and also any primary particles still present) to form iron oxide, IV. contacting of the particles from step III with an aqueous solution of a manganese compound, V. drying in the presence of oxygen and subsequent calcination in the absence of oxygen, resulting firstly in oxygen-comprising manganese compounds on the particles and finally reaction of these with the iron oxide to form a mixed oxide of the formula MnxFe3-xO4, where 0<x?2.