US2265645A

US2265645A - Electrolytic cell

Info

Publication number: US2265645A
Authority: US
Publication date: 1941-12-09
Anticipated expiration: 1958-12-09

Description

Dec. 9, 1941. a. E. JOHNSON ETAL ELECTROLYTIC CELL 3 Sheets-Sheet 1 Filed Dec. 22, 1937 N NW WON BK S SEQI H wbw N TR M m NANA T WE T NNmwL v A l QRW. Y B

Emmi-QM G. E. JOHNSON ET AL ELECTROLYTIC CELL Filed Dec. 22, 1937 3 Sheets-Sheet 2 INVENTORS GUNNARD E..TOHNSON REGINALD G. BOWMAN BY WILLAM :I. KNOXJR.

Dec. 9, 1941. G. E. JOHNSON ET AL ELECTROLYTIC CELL Filed Dec. 22, 1937 3 Sheets-Sheet 3 INVENTORS G NNARD E. JOHNSON REGINALD G.

BY WHJJAM J. KNOX,3'R

V ATTORNEYS Patented Dec. 9, 1941 Gunnard E. Johmon, Hammond,

Bowman, Gary, and William J. Hammond, Ind., assignors to smelting and Refining Company, Ind., a corporation of Montana Reginald G. Knox. 1n, tel-national East Chicag Application December 22, 1937, Serial No. 181,152' (Cl. 204-457) 7 Claims.

This invention relates to electrolysis and has for an object the provisionof certain improvements in electrolytic cells of the bifluid type and in the method of operating such cells. More particularly, the invention contemplates the provision of improved biiiuid cells of the type employed for producing insoluble metal compounds, such, for example, as .cells of the type employed for producing white lead in which the electrolytes are circulated through the cells.

A cell of the type employed heretofore usually includes a heavy concrete tank in which are suspended in alternate arrangement a plurality of anodes and a plurality of cathodes surrounded by permeable diaphragms. In the operation of the cell, the catholyte is introduced at the bottom of the catholyte compartment, and the anolyte is introduced near the top of the anolyte compartment. Consequently, the anolyte and catholyte flow through the cell in counter-current relationship and have different relative compositions at difierent levels in the cell with they result that a tendency toward the development of a non-uniform product is developed. Also, in the operation of the cell of the type employed heretofore, the structural arrangement of the various elements is such that the catholyte in the cathode compartment is maintained at a higher level than the anolyte in the cell. Owing to this diiference of head, it is necessary to use as the diaphragm a fabric of very low porosity. Fabric of this kind is expensive and difllcult to procure, and it' must be replaced after a time due to development of increased porosity.

In order to clean or repair a cell of the type employed heretofore, it is nece'sary to cut out of operation the entire cell with all of its anodes and cathodes. This is objectionable because it may cause an undesirably large reduction in the production of the cellroom. Increasing the number of cells also is inconvenient and ambersome, as the heavy concrete tank must first be poured and then installed.

The present invention provides for the elimination of many of the objectionable features of cells and methodsiof operation employed heretofore. The invention provides a cell of simple, light and compact construction which may, and preferably does comprise a single unit or which may comprise any larger number of units the inclusion of which will not prevent the attainment of the objectives of simplicity, lightness and compactness. A characteristic feature 'of the cell of the invention is the inclusion of the cathode as an element of the cell structure, an

element such, for example, as a wall of In the preferred single unit tim of or the invention, the end walls of the cell comprise parallel plates formed of a metal suitable for use as a cathode. Two diaphragm spaced cell are provided adiacentthe end walls and parallel thereto, forming a central anolyte compartment with catholyte compartments (1189 thatv the relative levels of the two electrolytes can be so adjusted that they are substantially equal or that either one is at any desired height above or below the other, and means are provided for introducing both electrolytes into the bottom portions of their respective compartments to permit the maintenance of co-current or parallel flow as distinguished from the counter-current flow employed heretofore.

The invention also provides cell-assembling apparatus to facilitate the installation and replacement of cells.

The apparatus of the invention provides for great flexibility in the operation of a cell room.

The cells of the invention, particularly the preferred single unit cells, are simple, compact and light. Cells can be replaced quickly and easily when repairs are necessary without disturbing the operation of other cells or units, and additional cells can be installed without difficulty.

The objects of the invention and the details of construction of a preferred cell of the invention and of the apparatus of the invention for use in assembling the same will be apparent from the following description taken in connection with the accompanying drawings which formv a part of this specification and in which Fig. 1 is a side elevation of the cell;

Fig. 2 is a top plan view of the same:

Fig. 3 is a section through Fig. 1 taken along the line 3-4;

Fig. 4 is a side elevation showing an assembly of cell, bus bars, piping, etc.; 1

Fig. 5 is a top plan view of the same; and

Fig. 6 represents a section through Fig. 4 along the line H.

A cell made in accordance with this invention consists essentially of two parallel iron face plates, two diaphragms betweenthe face platesparallel thereto and spaced therefrom sufflcienfly to form catholyte compartments between the same and the face plates, said diaphragm! being p from each other and spaced from the end walls of the pass through holes in the anode.

spaced from each other sumciently'to form an anolyte compartment and means for closing the bottom and sides of the cell.

In the drawings, which illustrate a preferred embodiment of this invention, the numeral l represents rectangular pan shaped iron sheets which may convenientlyv be regarded as face plates of the cell. These face plates are provided with flanged edges. Each cell comprises two such iron'plates which serve both as cathodes and as outer walls of the cathode compartment 2. The

face plates I are spaced apart by the main center J frame member I and the twoouter frame'members 3, these'frame members being of the shape of the outline of the face plates I, preferably U- shaped. The main frame member 4 ismade of insulating material, while the outer frame mem-- bers may be made of any suitable material but are preferably made of iron and are welded to the face plates.

;;The two diaphragms are stretched between the-side frame members or 'catholyte compartment spacers land the main frame member or anolytecompartment'spacers 4. Electrical conftactbetween the cathode or face plate I and thediaphragm I will result in the destruction of face plates, through the insulating strip, through the "outer edges' of the diaphragm and through the spacer framea Feedpipes are provided for introducing catholytev into the .catholyte compartments at or near the bottom. thereof and the feed pipe I6 is provided for-introducing anolyte near the bottom of the anolyte-compartment. A catholyte discharge spout-l is provldedat the: top of the front end of eachof the cathode compartments and an anolyte discharge pipe I! hear the top of the anolyte compartment. Copper contact bars 9 are riveted across the top of the cathode sheets Just aboveth. cathode discharge spouts .and extend beyond the rear of the cell to serve as rear supports for the cell, Within the anolyte compartinent and at right angles to the. face plates are suspended the U-shaped stay rods III which are bottom of the anolyte compartment. These serve to prevent-the diaphragms from bulging into contact with the anode l2. The upper ends of the stay rods are bent toward the face plates and are held in place by the wooden strips'll which serve also to seal the top of the catholyte comipartments. ,The anode is suspended from the coppe anode contact and support bar l3 (Fig. 6) by means of copper wire hangers I 4 which The lower edge of the anode is preferably some distance above the bottom of the anolyte compartment I In Figs. .,4 to 6, which show the framework upon which the individual cells are suspended and the assembly of cell, bus bars, piping, etc., thenumeral i! represents a suitable base upon .which are mounted the front and rear upright supporting frames 18. The anode bus bar I 9 which isplaced across the front supporting frame serves as a front support for the anode contact bar ljwhich is kept in its proper place between the copper pins placed in the bus bar I 9. The rear end of the bar I3 rests in a groove in a hard-rubber spacer 2| which is placed upon the wooden frame member 3| which extends across the rear frame supports l8.

In front of the cell and nearthe top of the cell-supporting framework is the catholyte discharge launder 22 and below it is the anolyte discharge launder 23. On the catholyte discharge launder 22 is mounted a front rest and spacer 24 which is provided with grooves in which the catholyte discharge spouts 8 rest. The rear of the cell is supported by resting the cathode contact bar 9 in grooves in the hard-rubber spacer 25 and von the copper cathode bus bar 26, both the -spacer 25 and the bar 26 being supported by the horizontal wooden-bar 21 which is secured to,

the rear frame supports l8. A rubber tube attached to the anolyte discharge pipe l5 carries the anolyte overflow from the cell into the anolyte launder.

The catholyte feed tubes 1. are connected to the hard-rubber catholyte manifold 28 and the anolyte feed tube I6 is connected to the hardrubber anolyte manifold 29. The wooden pieces 30 form with the base a drain launder through tages over other types of electrolytic cells. The

- concrete cell tank required by the commonly used I it is necessary to cut out a large number of units while in the single-unit cell, one unit at a time can be removed and quickly replaced with a new cell without interfering with the remaining cells in the cell room. Tov ii rease the'number of cells of the multiple unit type it is necessary first to pour and then install the heavyconcrete'tanks. The single-unit cells, on the other hand, are quite light, weighing only a little more than the cathode frames used in the multiple unit cell employed heretofore.

Additional cells can be inframes, launders and feed pipes. When the cells are arranged in rows with the electrodes in parallel in each row and the rows in series, with the single-unit cell, the current density can be varied easily by increasing or decreasing the number of cells suspended on the bus bar of each row.

As hereinbefore pointed out, one of the defects of the multiple unit cell employed heretofore that is corrected by the cell of this invention is the necessity of maintaining catholyte in the cathode compartment at a higher level than anolyte in the cell tank in order that the former can be discharged over the edge of the cell. This difference of head makes it necessary to use an expensive fabric of very low porosity as the diaso that they are equal or so that either one can be at any desired height above or below the other. This feature of the cell permits regulating the seepage through the diaphragms by adjusting the levels of the electrolytes thus eliminating the necessity of procuring the best grades of diaphragm fabric and of discarding the fabric when its seepage in service becomes too high. In the operation of the cell, the relative levelsare so ad justed and maintained as to provide the desired amount of seepage; Changes in rates of seepage due to increased porosity resulting from use are compensated for by varying the levels of the electrolytes.

In the heretofore customary use of the multiple-unit cell and other types of cells employing the expedient of circulating electrolytes, the anolyte and catholyte flow through the cell counter-current to each other and therefore vary in composition at different levels in the cell. This disadvantageous condition is not present in the single-unit cell of this invention, since both electrolytes enter at the bottom and discharge at the top, and a greater flow of anolyte through the cell can be maintained to decrease the amount of change in its composition without danger of.dislodging slime from the anodes. These changes in direction and rate of flow produce a more uniform product.

It is to be understood that the apparatus shown is only illustrative and that it may be considerably varied without departure from the invention.

We claim:

l. A bifluid electrolytic cell for producing insoluble metal compounds comprising a singleunit cell adapted to be removably supported as a unit on a frame and having a substantially U-shaped main frame of insulating material, a. corresponding substantially non-conducting U- shaped side frame secured to said main frame, a diaphragm clamped in place between the side frame and the main frame, means cooperating with the main frame and the diaphragm in a manner to form an anolyte compartment, a $01- uble anode disposed within the anolyte compartment, a cathode metal face plate secured to the outside of the side frame and spaced thereby a substantial distance from the diaphragm in a manner to form a catholyte compartment be-' soluble metal compounds comprising a single-- unit cell adapted to be removably supported as a unit on a frame and having a substantially U-shaped main frame of insulating material, corresponding substantially non-conducting U- shaped side frames secured to each side of said main frame,diaphragms clamped in place between soluble metal compounds comprising a singleunit cell adapted to be removably supported as a unit on a frame and having a' substantially frame and the main frame, means cooperating each side frame and the main frame in a manthe diaphragms, a soluble anode disposed within the anolyte compartment, a cathode metal face plate secured to the outside of each side frame and spaced thereby a substantial distance from the adjacent diaphragm in a manner to form catholyte compartments between the cathode face plates and the diaphragm with the face plates substantially insulated from the diaphragms, the cathode face plate being imperiorate and forming an external member of the cell, means for introducing and maintaining a body of anolyte in the anolyte compartment, and means for introducing and maintaining a body of catholyte in each catholyte compartment.

3. A bifluid electrolytic cell for producing inwith the main frame and the diaphragm in a manner to form an anolyte compartment, a solubleanode disposed within the anolyte compartmerit, a cathode metal face plate secured to the outside of the side frame and spaced thereby a substantial distance from the diaphragm in a mannerto form a catholyte compartment between said face plate and the diaphragm with the face plates substantially insulated from the diaphragm, the cathode face plate being imperforate and forming an external member of the cell, means for introducing anolyte into the lower portion of the anolyte compartment and for withdrawing anolyte from the upper portion thereof,

and means for introducing catholyte into the lower portion of the catholyte compartment and for withdrawing catholyte tion thereof. H I

4. A bifluid electrolytic cell for producing insoluble metal compounds comprising a singleunit cell adapted to be-removably supported as a unit on a frame and having a substantially U-shaped main frame of insulating material, corresponding substantially non-conducting U- shaped side frames secured to each side of said main frame, diaphragms clamped in place between each side frame and the main frame in a manner to form an anolyte compartment be-' tween the diaphragms, a soluble anode disposed within the anolyte compartment. a cathode metal face plate secured to the outside of each side frame and spaced thereby a substantial distance from the adjacent diaphragm in a. manner to formcatholyte compartments between the oathode face plates and the diaphragm with the face from the upper portions thereof in a manner to effect upward circulation of catholyte through the catholyte compartment in parallel flow relation with circulation of anolyte through the anolyte compartment.

5. In a bifluid electrolytic cell for producing insoluble metal compounds comprising a singleunit cell adapted to be removably supported as a unit on aframe and having a U-shaped main frame, corresponding U-shaped side frames secured to each side of the main frame, a diaphragm stretched and clamped in place between each side frame and the main frame in a manner to form an anolyte compartment between said .diaphragms, a soluble anode disposed within the anolyte compartment, and an imperforate cathode metal face plate secured to the outside of each side frame and forming an external member of the cell spaced a. substantial distance from the diaphragm and thereby forming catholyte compartments between the cathode face plates from the upper porand the diaphr gms, means for preventing the diaphragms from bulging inwardly toward thev anolyte compartment comprising relatively deep U-shaped stay rods of insulating material secured at their upper ends to the frame and having legs spaced apart a distance corresponding to the distance between the diaphragm, said stay rods, being mounted between the diaphragms in the plates and the frame form a container for an I anolyte compartment with the legs thereof positionedto resist inwardbulging of the diaphragm.

6. In a bifiuid electrolytic cell for producing in- I soluble metal compounds comprising a single-unit I cell adapted to be removably supported as a unit on a frame and having a U-shaped main frame,

a corresponding U-sliaped side frame secured to each side of the main frame, a diaphragm stretched and clamped inplace between the main frame and each side frame in a manner to form an anolyte compartment between the diaphragms, a soluble anode disposed within the anolyte compartment, and a cathode metal face plate secured" to the outside of said side frame and spaced thereby a substantial distance from the diaphragm, the cathode face plate being im-; perforate and forming an external member of the cell, means for insulating the diaphragm from said cathode comprising a layer of insulating'material interposed between the edge por tions of the diaphragm and the corresponding adjacent edge portions of the cathode faceplate.

insoluble metal compounds comprising a plurality of unit bifiuid electrolytic cells each comprising cathode plates forming a structural part of the cell and being mounted on asubstantially U shaped frame insuch manner that the cathode electrolyte, diaphragms dividing each cell into an inner anolyte compartment and outer catholytecompartments, a soluble anode disposed in the anolyte compartment, a catholyte discharge spout communicating with the catholyte compartments and rigidly secured to a structural element of the 7 cell at one side near the top thereof, and a cathfl. An electrolytic cell assembly for producing ode contact bar secured rigidly to a cathode plate at the other side of the cell near the top thereof, and means for supporting said cells comprising a base, front and rear upright supports, a, horizontal cathode bus bar mounted on one of said supports and arranged to, receive the cathodes contact bars of a plurality of cells in a manner to provide support for each unit cell, and a catholyte overflow launder mounted on the other of said supports and arranged to receive the catholyte discharge spouts of a'plurallty of cells in a manner to provide support for each unit cell, said discharge spouts and cathode contact bars constituting major load-carrying members of the cells mounted on the cell supporting means.

' GUNNARD E. JOHNSON. REGINALD GLBOWMAN. WILLIAM J. KNOX, JR.