JPS5716182A - Diaphragm type alkali chloride electrolytic tank - Google Patents

Abstract

PURPOSE:To prevent lowering of current efficiency, in preparing NaClO by electrolyzing salt water in an electrolytic tank equipped with a diaphragm, by flooding a part of an anode liquid into a cathode chamber through a communicating pipe to prevent a cathode liquid from being entered into an anode chamber. CONSTITUTION:An electrolytic tank 1 is partitioned into an anode chamber 5 and a cathode chamber 6 by a longitudinal diaphragm 2 and saturated salt water 10 is entered into the anode chamber 5 to be electrolyzed by an anode 3 and a cathode 4. In this case, a Cl gas formed in the anode chamber 5 is sent to a reaction chamber 8 under the electrolytic tank 1 through a pipe 11 as well as NaOH produced in the cathode chamber 6 is fallen onto a perforated plate 9 positioned at an upper part of the reaction chamber 8 through a pipe 15 along with diluting water 16 and dropped into the reaction chamber 8 through the perforated plate 9 and reacted with the Cl gas to prepare an aqueous NaClO solution and the resultant solution is taken out from an outlet 19. In this case, an anode liquid 5' is flooded into the cathode chamber 6 through a communicating pipe 12 provided to a lower part of the diaphragm 2 as well as a level of the anode liquid is kept higher than that of the cathode liquid to prevent the cathode liquid 6' from being invaded into the anode liquid and, thereby, the lowering of Cl generating efficiency at the anode 3 is prevented.