Method for producing a multi metal oxide catalyst, method for producing unsaturated aldehydes and/or carboxylic acids and band calcination device

A process for the preparation of a catalyst, comprising:

• preparing a particulate catalyst precursor which contains oxides and/or compounds of elements other than oxygen which constitute a multimetal oxide material, wherein said compounds of elements other than oxygen can be converted into oxides, and
• converting said particulate catalyst precursor by calcination into a catalytically active form by passing a stream of said particulate catalyst precursor at substantially constant speed through at least one calcination zone for calcination and passing a gas stream through the stream of said particulate catalyst precursor perpendicularly to the direction of advance of the stream of said particulate catalyst precursor in the calcination zone,
• wherein a maximum variation of the temperature as a function of time is ≦5° C.;
• wherein a maximum local temperature difference in the calcination zone is ≦5° C.;
• and
• wherein said catalyst comprises an active phase of said multimetal oxide material.