GB544608A - Improvements in and relating to electrolytic cells - Google Patents

Abstract

544,608. Electrolytic cells. SHAWINIGAN CHEMICALS, Ltd. Sept. 1, 1941, No. 11120. Convention date, Sept. 10, 1940. [Class 41] An electrolytic cell comprises three adjoining upper chambers 50, 60, 90, spaced from a fourth chamber 10 by a series of tubular electrodes enclosed in a cylindrical casing, not shown, forming a compartment for the circulation of cooling liquid. The lowermost chamber or header 10, provided with a catholyte inlet 15, is bolted to a graphite member 20 in which the lower ends of the cathode tubes 30 are set, the upper ends being engaged in a similar member 40. The chamber 10 carries a porcelain or other non- conducting perforated plate 17 on which rest semi-permeable diaphragm tubes 110 of an aluminium oxide composition, these supporting in turn by means of spacers 112, the hollow graphite anodes 80. The upper ends of the diaphragms are received in openings in the base of the chamber 60, the anodes extending up to bushings in a member 70 which constitutes the base of the uppermost or gas chamber 90. The positive and negative current connections are made with the parts 70, 40 respectively. The cell may be used for the production of chromous chloride and chlorine in the manufacture of ethylene chlorhydriri. An aqueous solution of the catholyte, chromic chloride, is pumped into chamber 10 from which it flows between the surfaces of the cathodes and the diaphragms, emerging from the outlet 55 to return to the storage tank. The anolyte, a solution of HC1 which may contain some CrC13, enters by the tube 62, and flows down through the hollow anodes into the compartment space between the anodes and the diaphragms into the chamber 60 to return through tube 65 to the storage tank. Chlorine evolved at the anodes passes through pipe 61 into the gas dome 90 and is collected from pipe 63. Hydrogen ions produced at the cathodes reduce the chromic chloride to chromous chloride, the issuing catholyte being circulated through a tower against a stream of acetylene which is thus hydrogenated to ethylene. Catholyte and anolyte are both replenished with HC1 before re-entry. The ethylene and chlorine produced are subsequently re-acted to form ethylene chlorhydrin.