Device for the evaporation of a liquid

Apparatus comprises several chambers (9, 10, 11) for carrying out solid body catalyzed reactions; and a common vaporizing unit (2) for vaporizing liquid educts (1). One region of the vaporizing unit is partially surrounded by the chambers. Preferred Features: The vaporizing unit is completely surrounded by the chambers and has catalyst layers. The vaporizing unit is rigidly fixed to the chambers, preferably by a thermal coupling. The educt is a hydrocarbon, ether and/or alcohol.