US3891531A

US3891531A - Electrolytic diaphragm cells including current connection means between the cell base and anode

Info

Publication number: US3891531A
Application number: US316515A
Authority: US
Inventors: Pierre Bouy; Daniel Masure; Paul Collon; Jean-Marie Pigeaud; Bernard Sartre
Original assignee: Rhone Progil SA
Current assignee: Rhone Progil SA
Priority date: 1971-12-23
Filing date: 1972-12-19
Publication date: 1975-06-24
Anticipated expiration: 1992-06-24
Also published as: SE388640B; AT319278B; ES409880A1; NO138254C; DE2262525A1; IT1052122B; FR2164495B2; BR7209044D0; DE2262525B2; JPS4878083A; NO138254B; GB1405609A; BE793282A; NL7217438A; FR2164495A2; CA979394A; CH562328A5

Abstract

Electrolytic diaphragm cells are provided comprising a plurality of vertical substantially flat and hollow anodes formed, as regards at least one of their two substantially parallel faces, by a sheet of a film-forming metal, said anodes being secured to the base of the cell by means of extended portions which pass through the base, characterized in that the extended portions comprise a core made of a metal which is a good electrical conductor, which core is covered by a sheath made of a filmforming metal, a good electrical contact being ensured between the sheath and the core. The core of the extended portions is exposed where it passes through the base of the cell, with the electrical connection between the base and the core comprising resilient metal parts arranged between the core and the base.

Description

United States Patent Bouy et al.

[75] Inventors: Pierre Bouy, Enghien-les-Bains;

Daniel Masure, La Madeleine; Paul Collon, Autreville; Jean-Marie Pigeaud, Martigues; Bernard Sartre, Levallois-Perret, all of France [73] Assignee: Rhone-Progil, Paris, France [22] Filed: Dec. 19,1972

[2!] Appl. No: 316,515

{30] Foreign Application Priority Data Dec. 23, 1971 France 71.46296 [52] US. Cl. 204/263; 204/252; 204/266; 204/286; 204/290 F [51] Int. Cl B0lk 3/10 [58] Field of Search 204/252, 266, 286, 290 F, 204/263 [56] References Cited UNITED STATES PATENTS 3,515,661 6/1970 Coulter 204/286 3,591,483 7/1971 Loftfield et al. l. 204/252 June 24, 1975 3,632,497 1/1972 Leduc 204/266 OTHER PUBLICATIONS Cotton, J. B., Platinum-faced Titanium for Electrochemical Anodes, ln Platinum Metals Review, 2(2): pp. 4547, April, 1958.

Primary Examiner.l0hn H. Mack Assistant Examiner-W. 1. Solomon [57] ABSTRACT Electrolytic diaphragm cells are provided comprising a plurality of vertical substantially flat and hollow anodes formed, as regards at least one of their two substantially parallel faces, by a sheet of a film-forming metal, said anodes being secured to the base of the cell by means of extended portions which pass through the base, characterized in that the extended portions comprise a core made of a metal which is a good electrical conductor, which core is covered by a sheath made of a film-forming metal, a good electrical contact being ensured between the sheath and the core. The core of the extended portions is exposed where it passes through the base of the cell. with the electrical connection between the base and the core comprising resilient metal parts arranged between the core and the base.

4 Claims, 4 Drawing Figures PATENTEI] JUN 24 I975 SHEET K VI, V

ELECTROLYTIC DIAPHRAGM CELLS INCLUDING CURRENT CONNECTION MEANS BETWEEN THE CELL BASE AND ANODE BACKGROUND OF THE INVENTION The present invention relates to electrolytic diaphragm cells provided with flat and hollow metal anodes which are formed, at least as regards one of their two parallel faces, by an apertured sheet or a lattice made of titanium or a metal or alloy having similar anodic properties. The anodes are also provided with extended portions for the input of electric current and for fixing the anodes to the bases of the cells.

The advantages are known of using titanium or metals or alloys having similar properties instead of graphite anodes in electrolytic cells, with such anodes being covered with a conducting metal which is not attacked by the electrolytic solutions. In particular, French Pat. No. 1,600,249 describes constructions in which such metal anodes are extended by metal portions for securing them to the base of the cells, and for the input of the electrical current.

It is an object of the present invention to provide electrolytic diaphragm cells having improved anodes.

It is also an object of the present invention to provide electrolytic diaphragm cells having anodes which permit a more favorable distribution of electrical current.

These and other objects will be apparent to those skilled in the art from the present description, taken in conjunction with the appended drawings, in which:

FIG. I is an elevational view of an anode of the invention.

FIG. 2 is an elevational view of the lower part of the anode of FIG. 1 having an extended portion fastened to the base of a cell.

FIG. 3 is an elevational view of another anode extended portion fastened to the base of a cell.

FIG. 4 is an elevational view of the lower part of an anode extended portion fastened to the base of the cell, with the electrical connection to the core portion shown.

GENERAL DESCRIPTION OF THE INVENTION The improved constructions now described of the present invention use extended portions comprising a core made of a material which is a good electrical conductor, the core being covered with a sheath of titanium or other film-forming metal or alloy having similar anodic properties, so that a perfect electrical connection is ensured between the sheath and the core. The use of such extended portions makes it possible to achieve a reduction in the drops in potential, by supplying current directly to the core of the extended portions, the active parts which are the flat faces of the anodes themselves being welded to the sheath of the extended portions. Moreover, and advantageously, the extended portions can extend in space between the two parallel faces of the anodes, as far as their upper part, and can be welded to the faces of the anodes in such a way that the most favourable distribution of the electrical current is ensured at that point.

In practice, depending on the dimensions of the anodes and their electrical characteristics, one or more of such extended portions is used per anode, the use of a single extended portion enjoying the advantage, however, that it is not subjected to forces due to expansion of the elements of the anode. Extended portions of this nature are preferably made from jointly drawn members which are cylindrical in shape. It is easy to see that such a cylindrical shape permits various machining operations for ensuring a current feed to the extended portions.

A first way in which electrical current can be supplied comprises exposing the conducting core of the extended portion at its lower end which passes through the base of the cell. This permits securing to the core in various known manners the current supply leads. It also provides for a screw-thread on the sheath where it passes through the base, and securing thereto by welding above the screw-thread a washer of the same or a similar metal, and thus to tighten the extended portions to the cell base. Also provided is sealing by means of a sealing gasket, which is preferably toric or toroidal, interposed between the washer and the base. The current supply leads can be secured to the base of the cell and, if the base is metal, they can then act as a general current input for the anodes.

Another way in which the electrical current can be supplied to the extended portions of the anode in the case where the base of the cell is of metal, comprises gripping the conducting core of the extended portions of the anode, which is bared or exposed where it passes through the base of the cell, by the metal of which the base itself is made. This gripping effect can be achieved by simply making the core have a force or frictional fit in the base. However, it is preferably achieved by shrink-fitting, by establishing before assembly a sufficient temperature difference between the base and the extended portions of the anode, for example, by immersing the latter in liquid nitrogen before fitting. Upon expansion where returning to atmospheric or elevated temperature, a tight fit is possible. Dismantling, if required, can be effected by various means which can be used in combination, and which can include (1) screw extractors, (2) by providing the various anchorages required, (3) conical machining of the core of the extended portions, (4) passages provided in the core so that a cooling fluid can be circulated therein, and (5) means for heating the base. In this second way of feeding the electrode with current, it is obvious that sealing can be effected in a smilar manner to that described above, by squashing, when the anodes are assembled, a sealing gasket comprising a suitable elastomer, precisely by the amount required, between a washer secured to the extended portions and the base of the cell. Also, this may be accomplished by clamping the joint after assembly against the base by means of a washer which is screwed on to the sheath of the extended portions. It is also possible to effect sealing by welding on by means of their edges thin pieces of titanium or other film-forming metal, replacing the washers used hereinbefore, for protecting the base of the cell with titanium.

A third way in which the current supply can be provided, comprises using a conducting metal for making the base of the cell and making a connection between the base and the extended portions by means of resilient contacts arranged in an annular space provided between the conducting core of the extended portions, which core is bared where it passes through the base, and the aperture through which it passes through the base, sealing being effected in the same manner as hereinbefore, by means of sealing gaskets.

SPECIFIC DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described by way of example hereinafter with reference to the accompanying drawings.

FIG. 1 shows an elevational view of an anode according to the invention comprising two expanded or apertured sheets I of titanium or other film-forming metal, such as tantalum, tungsten, zirconium, etc. These are welded along their vertical axes to the tianium sheath of a cylindrical jointly-drawn member 2 comprising copper and titanium. The titanium sheets 1 may be in the form of a lattice. Threaded on to and welded to the lower part of the member 2 is a washer 3 comprising titanium or other film-forming metal, which, by way of the toric sealing gasket 4, provides for sealing with respect to the polyester base 5 of the electrolytic cell. The titanium sheath of the part of the member 2 which is located below the washer 3 is screw-threaded so that the anode can be tightened to the base of the cell by means of a nut 6. The copper core 7 of the lower end of the member 2 is bared or exposed and carries a sleeve 8 connected by a bunch 9 of copper wires to the electric current supply rod 10. The vertical edges of the titanium sheets I are connected by welding by means of members which are also made of expanded titanium sheets.

FIG. 2. shows an elevational view of the lower part of an anode according to the invention having its extended portion which is gripped in the base of the cell, the anode itself being made as described hereinbefore with reference to FIG. I. The extended portion 11 is a cylindrical jointly drawn member comprising copper and titanium. The copper core of the lower part of the copper-titanium member is exposed at 12 over a height corresponding to the thickness of the base of the cell, the base being preferably made of cast aluminum and indicated by reference 13. A passage 14 in the copper core permits the temperature of the member to be reduced by circulating liquid nitrogen therein, so that assembly and dismantling can be effected by shrinkfitting as described hereinabove, the machining tolerances of the copper core and the bore of the corresponding hole in the base of the cell being gauged in consequence.

Protection from corrosion is effected in the following manner; the base 13 of the cell is covered by a titanium sheet 15 in which are provided circular apertures coaxial with the electrode extended portions. The edge of the apertures is relieved at 16; a washer-shaped member 17 provided with a relieved edge 18 and made from a titanium sheet of the same thickness as the titanium sheet 15 is welded at 19 to the sheath 20 of the member 11, and the

edges

16 and 18 are welded at 21. The welding can be ground off before dismantling the anode.

FIG. 3 also shows another mode of gripping an anode extended portion of an anode of the invention in the base of the cell. This Figure again shows the cylindrical copper-titanium member 11, the sheath 20 of the member 11, the copper core exposed at 12 at the lower end of the member 11, and the cooling passage 14. In this construction, the base 13 of the cell is covered with a titanium sheet 22 provided with circular apertures through which the extended portions pass. Welded to the sheath 20 is a titanium washer 23 for scaling to the base by means of a toric seal 24 which is crushed or flattened during assembly.

Flg. 4 shows and elevational view of the lower part of an anode extended portion, and the means for electrical connection between the core of the extended portion and the metal base of the cell. This Figure shows the copper-titanium jointly drawn member 25 covered with a sheath 26, a washer 27 welded to the sheath 26, and a toric seal 28. The lower bared end 29 of the member 25 is here provided with an electrolyte leakage purge hole 30, and terminated by a screwthread. The copper base 31 of the cell has apertures through which pass the exposed ends of the jointlydrawn members, and is protected by a titanium sheet 32 having apertures with turned-down edges, corresponding to the apertures in the base 31. The diameter of the apertures in the base is such that an annular space is provided, for positioning rings with multiple resilient contact means 33 for making an electrical connection between the extended portions and the base of the cell which serves in this construction as a general current input. The electrode extended portion is secured by clamping by means of a nut 34 which is screwed on to the screw-threaded end of the core.

In the foregoing embodiments, it is to be understood that where a titanium component is referred to, it may be substituted with a corresponding component fashioned of another film-forming metal or alloy thereof.

The terms and expressions which have been employed are used as terms of description and not of limitations, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed.

What is claimed is:

1. An electrolytic diaphragm cell comprising a plurality of vertical substantially flat and hollow anodes formed, as regards at least one of their two substantially parallel faces, by a sheet of a film-forming metal, said anodes being secured to the base of the cell by means of extended portions which pass through the base, characterized in that the extended portions comprise a core made of a metal which is a good electrical conductor, which core is covered by a sheath made of a filmforming metal, a good electrical contact being ensured between the sheath and the core, said base of the cell being of metal, which base is covered with a sheet of film-forming metal, said core of said extended portions is exposed where it passes through the base of said cell, the electrical connection is made by means of metal parts arranged between said core and said base and resting resiliently against said core and said base.

2. An electrolytic diaphragm cell accordding to claim 1, wherein said anode rests on said base by means of an appended washer resting on a toric seal.

3. An electrolytic diaphragm cell according to claim 1, wherein said extended portion is provided with a channel communicating with the top of said base and a point of discharge below said base.

4. An electrolytic diaphragm cell according to claim 1, wherein said sheet of film-forming metal covering said metal base is welded to a washer-shaped member, attached to said sheath, at raised portions to effect a seal.

Claims

1. AN ELECTROLYTIC DIAPHRAG CELL COMPRISING A PLURALITY OF VERTICAL SUBSTANTIALLY FLAT AND HOLLOW ANODES FORMED, AS REGARDS AT LEAST ONE OF THEIR TWO SUBSTANTIALLY PARALLEL FACES, BY A SHEET OF FILM-FORMING METAL, SAID ANODES BEING SECURED TO THE BASE OF THE CELL BY MEANS OF EXTENDED PORTIONS WHICH PASS THROUGH THE BASE, CHARACTERIZED IN THAT THE EXTENDED PORTIONS COMPRISE A CORE MADE OF A METAL WHICH IS A GOOD ELECTRICAL CONDUCTOR, WHICH CORE IS COVERD BY A SHEATH MADE OF A FILMFORMING METAL, A GOOD ELECTRICAL CONTACT BEING ENSURED BETWEEN THE SHEATH AND THE CORE, SAID BASE OF THE CELL BEING OF METAL, WHICH BASE IS COVERED WITH A SHEET OF FILM-FORMING METAL, SAID CORE OF SAID EXTENDED PORTIONS IS EXPOSED WHERE IT PASSES THROUGH THE BASE OF SAID CELL, THE ELECTRICAL CONNECTION IS MADE BY MEANS OF METAL PARTS ARRANGED BETWEEN SAID CORE AND SAID BASE AND RESTING RESILIENTLY AGAINST SAID CORE AND SAID BASE.

3. AN ELECTROLYTIC DIAPHRAGM CELL ACCORDING TO CLAIM 1, WHEREIN SAID EXTENDED POTION IS PROVIDED WITH A CHANNEL COMMUNICATING WITH THE TOP OF SAID BASE AND A POINT OF DISCHARGE BELOW SAID BASE.