US2368861A - Electrolytic cell - Google Patents

Description

Feb. 6, 1945. D. R. MEANS ELECTROLYTIC CELL I 3 Sheets-Sheet 1 Filed June 25, 1940 Fig.2.

INVENTOR. DWLG/HT F?.MEAN$ BY fi Km ATTORNEY.

. Feb. 6, 1945. D. R. MEANS 2,368,861

ELECTROLYTIC CELL Filed June 25, 1940 3 Sheets-Sheet 2 INVENTOR. DWIGHT R. MEANS ATTORNEY.

Feb. 6,1945. D. R, MEANS ELECTROLYTIC CELL Filed June 25, 1940 s Sheets-Sheet :5

INVENTOR. DWIGHT F2. MEANS ATTORNEY.

Patented Feb. 6, 1945 ELECTROLYTIC CELL Dwight R. Means, Wadsworth, Ohio, asslgnor to Hooker Electrochemical Company,

Niagara Falls, N. Y., a corporation of New York Application June 25,1940, Serial No. 342,308

- 1 Claim.

This invention relates to an improved electrolytic cell for use in the electrolysisof alkali metal chloride solutions and the preparation of chlorine and alkali metal hydroxide. In accordance with the present invention, -I have been able to devise a novel electrolytic cell structure of improved and Fig. 1 is a plan view of a preferred form of my cell with a portion of the cover being broken away to reveal the cell interior.

Fig. 2 is a vertical sectional view on line A-A of F18. l.

Fig. 3 is a vertical sectional view on line 3-3 of Fig. 1.

Fig. 4 is a view of a modified form of anode assembly which maybe constructed in accordance with my invention.

Fig. 5 is a vertical sectional view of the cathode assembly and,

Fig. 6 is a detailed view upon an enlargedscalc of a portion of the cathode assembly.

It will be noted that the electrolytic cell comprises an anode assembly I, which rests upon suitable insulating supports 4, a cathode assembly 2, resting upon the anode assembly, and a suitable cover 3, resting upon the cathode 3, the several assemblages being clamped together in order to form a unitary structure.

In accordance with one modification, the as- 1y resistant metal, such as silver or lead in which the anodes are driven. If the carbon becomes attacked during operation, these sleeves may then be replaced by others having a smaller internal diameter, thus permitting a firm support of the anodes. As a support for the cathode member, annular ring [4, of suitable material is placed upon the periphery of the anode base member. This ring may be of any suitable rigid material. such as rubber-covered metal, resins, etc. In order to insulate the base member from the electrolyte, the base ordinarily is covered with some insulating material, such as bitumen or putty l3.

The cathode structure comprises a main fram 2, of box-like construction which is provided with a pair of chambers 21, at two opposed ends theresembly structure comprises a suitable metallic of the anode slab maybe tapered slightly and may be driven intosuitably constructed slots or 4 holes in the base member, or the anode may be [mounted by means of threaded screws or other trical contact between base II and the anode members.

with metallic sleeves of a'relatively soft, chemicalsupporting means capable ofv establishing an elec- Alternatively; the holes or sockets in which the cathodes are inserted may be provided of, and a plurality of hollow perforated cathode members 2|, of elongated construction extending across the cell and communicating at each end thereof with the chambers 21. members are enerally constructed of metal screen or other suitable foraminous metallic material and are of elongated cross section, being mounted vertically between the banks of vertically extending anodes, as shown in Figs. 1 and 2. These perforated members are covered by suitably formed diaphragms of fibrous materials such as may be obtained by wrapping asbestos paper or other similar product around the members and fastening with adhesive or other convenient means. ode main frame and the imperforate area be-. tween the cathode members may be provided with an insulating coating 23, in order to avoid possible short-circuiting of the cell and also to prevent generation of caustic adjacent imperiorate portions of the'cathode. Chambers 21 are provided with one or more outlets for hydrogen 25, and for caustic liquor 26.

The cover member 3, which rests upon the cathode structure may be of any convenient construction which is adapted to the collection of chlorine and the introduction of fresh electrolyte. As shown in Figs. 1 and 2, the cover is provided with suitable brine inlets 3|, 32 and 34, and an electrolyte manometer connection 36, for indication of the liquor level. Chlorine evolved in the electrolyte rises to the top of the cell and is removed through outlet 33. Gaskets or other sealing means It, are generally provided between the anode and cathode assemblies and between the These cathode The upper and lower edges of the cath-' as electroplating, or by other means.

(not shown) in a manner similar to that shown in U. S. Patent 1,866,065, granted to K. E. Stuart.

In the normal operation of this cell, the cell is filled with a solution of sodium chloride approximately to the level just above connection 36, and a suitable potential diilerence is applied between anode base II, and cathode shell. The brine solution is moved into contact with perforated cathode members 2l, and fiows more or less continuously therethrough, resulting in the production of sodium hydroxide and hydrogen. The solution thus formed fiows through outlets 22 and 28 into chamber 21, where it is collected. The hydrogen formed rises to the top of cathode chambers 21, and is withdrawn through outlet 25. Chlorine is evolved adjacent the anodes and rises to the surface of the electrolyte where it is collected and withdrawn at 33. The caustic solution is removed from the cell through outlets 28.

In accordance with a further modification, it is possible to use a modified form of anode structure, such as may be illustrated in Fig. 4. In accordance with this modification, I may provide a suitable metallic base member 40, which may be of any desired conductive material, but preferably is of copper. In order to prevent attack of the copper by the electrolyte within the cell, the copper is provided with a thin sheath of platinum 4|. Wires, sheets or perforated wire gauze anodes 42 may be mounted vertically upon the anode base, and in general, it is found desirable to construct these anodes of similarly cladded material. Thus, these anodes may comprise sheets, wires, or metallic gauze made from copper or copper alloys, cladded with platinum or similar resistant material. This protective sheath may be applied to the base copper by any means which is effective for the purposes, such In accordance with one suitable modification, it is found desirable to weld or otherwise attach thin platinum foils upon the surface of theanode members as is understood in the art of cladding metal sheets. It is found that a cell of the construction above-indicated is considerably superior to other cells of similar structure, having unusually high efilciencies. In addition, it has been noted that higher current densities may be used and that the life of the anodes is appreciably longer than that of anodes in other electrolytic cells of this type.

Although the present invention has been described and claimed with reference to the specific details of certain embodiments thereof, it'is not intended that suchd'etails shall be regarded as limitations upon the scope of the invention, except insofar as included in the accompanying claim.

Iclaim:

An electrolytic cell comprising an anode assembly consisting of a fiat metallic plate horizontally disposed as a conductive base member and having a plurality of recesses and rows of anode plates fitting in said recesses in said base plate so as to be in electrical contact therewith,

. each row of anode plates extending continuously across from one side of the cell to the other, a cathode assembly insulated from and supported by said base plate and including a peripheral frame having hollow chambers constituting the side walls of the cell and a plurality of hollow foraminous cathode members extending continuously and completely across the cell between said anode plates and opening at each end into the corresponding side chamber of the cathode assembly, and upper and lower outlet means permitting outflow of gases and liquids respectively from said chambers and from end to end of said hollow cathode members.

DWIGHT R. MEANS.

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