VERFAHREN ZUR HERSTELLUNG EINES DIAPHRAGMAS FUER ELEKTROLYSEZELLEN

The process relates to the formation of diaphragms, for example those used for alkali chloride electrolysis in an aqueous solution. The formation of a layer-type diaphragm, accreted on a hollow diaphragm support from a slurry having a high solids content of diaphragm material, is made uniform. During the accretion step, the diaphragm support is periodically lifted and lowered in the slurry (frequency 0.1-10 min-1; amplitude 10-100 cm; velocity 2-20 cm/sec); its topside, at the upper reversal point of the oscillating motion, has a certain spacing (10-25 cm) from the constantly measured height of the level of slurry in the accretion tank and its underside cannot reach below a minimum distance (30 cm) from the bottom of the basin. The suction pressure of the slurry through the hollow diaphragm support is maintained at a constant value and is controlled (10-500 mbar below the atmospheric pressure of the surroundings). The accretion step can be subdivided into time intervals between which the frequency and the suction pressure are increased stepwise. The electrolysis process becomes more economical with the use of the diaphragm produced according to this invention.