Abstract: A module having a plurality of chambers which are seated relatively close to each other in a flow-through reservoir having a feed inlet and an oppositely located retentate outlet. The chambers include pervaporation chambers which have a permeation-selective layer and heating chambers. The pervaporation chambers and the heating chambers are alternatingly disposed and supported in cutouts within comb-shaped supports. The flow-through reservoir is box-shaped and has removable, tightly secured longitudinal end walls, one of which supports all pervaporation chambers, the other of which supports all heating chambers. The module is highly efficient due to flow and temperature distribution conditions which remain extremely exact.