초록 ▼

Disclosed is a niobium(Nb)-containing aqueous solution for use in producing a Nb-containing oxide catalyst, wherein the oxide catalyst comprises an oxide of a plurality of active component elements including Nb and is for use in a catalytic oxidation or ammoxidation of propane or isobutane in the ga

Disclosed is a niobium(Nb)-containing aqueous solution for use in producing a Nb-containing oxide catalyst, wherein the oxide catalyst comprises an oxide of a plurality of active component elements including Nb and is for use in a catalytic oxidation or ammoxidation of propane or isobutane in the gaseous phase, and wherein the oxide catalyst is prepared by a process comprising mixing the Nb-containing aqueous solution with (an) aqueous mixture(s) containing compounds of active component elements of the oxide catalyst other than Nb, to thereby provide an aqueous compound mixture, and drying the aqueous compound mixture, followed by calcination. The Nb-containing aqueous solution comprises water having dissolved therein a dicarboxylic acid, an Nb compound and optionally ammonia, wherein the dicarboxylic acid/Nb molar ratio (.alpha.) satisfies: 1.ltoreq.(.alpha.).ltoreq.4, and the ammonia/Nb molar ratio (.beta.) satisfies: 0.ltoreq.(.beta.).ltoreq.2. By the use of the niobium-containing aqueous solution, it has become possible to produce efficiently an oxide catalyst which, when used in a catalytic oxidation or ammoxidation of propane or isobutane in the gaseous phase, exhibits high catalytic activity, and which, therefore, can be advantageously used for producing (meth)acrylic acid or (meth)acrylonitrile in high yield.

대표청구항 ▼

[ We claim:] [1.] A niobium-containing aqueous solution for use in producing a niobium-containing oxide catalyst,wherein said niobium-containing oxide catalyst comprises an oxide of a plurality of active component elements including niobium and is for use in a catalytic oxidation or ammoxidation of

[ We claim:] [1.] A niobium-containing aqueous solution for use in producing a niobium-containing oxide catalyst,wherein said niobium-containing oxide catalyst comprises an oxide of a plurality of active component elements including niobium and is for use in a catalytic oxidation or ammoxidation of propane or isobutane in the gaseous phase, and wherein said niobium-containing oxide catalyst is prepared by a process comprising mixing said niobium-containing aqueous solution with an aqueous mixture or aqueous mixtures containing compounds of active component elements of said oxide catalyst other than niobium, to thereby provide an aqueous compound mixture, and drying said aqueous compound mixture, followed by calcination,said niobium-containing aqueous solution comprising water having dissolved therein a dicarboxylic acid, a niobium compound and optionally ammonia, wherein the molar ratio (.alpha.) of said dicarboxylic acid to the niobium contained in said niobium compound satisfies the following relationship: 1.ltoreq.(.alpha.).ltoreq.4, and the molar ratio (.beta.) of said ammonia to the niobium contained in said niobium compound satisfies the following relationship: 0 .ltoreq.(.beta.).ltoreq.2.