US1096085A - Electrolytic process and apparatus. - Google Patents

Description

G. WHITE.

BLBGTROLYTIG PROCESS AND APPARATUS.

I. APPLICATION FILED 00127, 19,18 1,096,085, Patented May 12, 1914.

3 SHEETS-SHEET l.

C. WHITE.

BLBGTROLYTIG PROCESS AND APPARATUS.

APPLICATION FILED 00T. 7, 1913..

111181111101 May 12, 1914.

3 'SHEETS-SHEET 2.-

G. n WHITE. BLBCTROLYTIG PROCESS ANDAPPARATUS.

' 'APPLICATION FILED OCT. 7! 1913.

Patented May l1 2, 1914.

3 SHEETS-SHEET 3'.

CARTER WHITE, OF LON'DON, ENGLAND.

ELECTROLYTIC PROCESS AND APPARATUS.

Specification of Letters Patent.

Patented May 1 i?, 1914.

Application filed October 7, 1913. Serial No. 793,884.

Be it known that l, Can'rnn lili-irre, oi 1S Old Sivan Lane, in the city of London, Fing land, chemist, have invented certain new and uset'ul Improvements in or Relating to llectrolytic Processes and Apparatus, ot which the following is a specification.

Thisinventiou relates to the electrolysis in simple cells (i. e. wit-hout diaphragms) ot solutions that evolve a gaseous anion liable to redissolve in or be taken up by the electrolyte, and the object of the invention is more etlectively to remove such gaseous anion and restrain the same from being taken up again by the electrolyte, While enabling the electrolysis to be conducted economically and with a good output. l

The invention is particularly intended for application to the electrolysis ot' solutions ot' sodium or potassium chlorid in simple cells, where, is known, the chlorin liberated at the'anode tends to dissolve in the bath and torni hypochlorite, chlo rate,' or other complex ch'lorin Compounds. rlhis dissolving of chlorid in the electrolyte can be obviated or substantially reduced by means of the present invention.

The invention is not restricted to the electrolysis of sodium or potassium chlorid solutions, but may be employed in any other cases where it is desirable to remove from an electrolyte a gaseous anion liberated in the electrolysis, iin order to' prevent the same frondissolving` in or reacting with the electrolyte. c

As another example the invention may be employed for the electrolysis of sodium or potassium nitrate solutions.

l will describe the invention as applied t'or the electrolysis of a solution ot chlorid of sodium or potassium.

According to the invention l apply local heat and exhaust to a portion ot the electrolyte (i. e. the anolyte) contained near the anode in an anode chamber communicating below the anode with the electrolyte in the t-cll outside. without interposition oi' a diaplu-agm. The locally heated portion of the electrolyte is drawn up around the anode above the levehot the electrolyte in the cell,

b v the exhaust which is applied for drawing away the gaseous anion. pump, exhauster. or any other suitable means may be employedl :tor drawing away the chlorin and may serve to ldraw the electrolyte up around the anode in the anode chamber as before mentioned to permit the heat to be applied to this portion above the level of the liquid in the cell.Y By the combined elt'ect of the local heating of the portion ,of the electrolyte near the anode and of the ex haus-tinglr action exerted above the same, the chlorin can be quickly and electively removed as liberated. With a view to assisting further in the attainment of this object l may cool the liquid below or in the neighborhood ot' the heated portion, so as to conline the heat more closely to the electrolyte in the neighborhood of the anode. sired the, brine or other solution to be electrolyzed may itself be used for cooling the electrolyte in the chambers below the heated portions.

ln carrying the invention into eltect I may arrange in the cell one or more anode tubes depending into the electrolyte and connected at to.; to a pump or other means for drawing olf or exhausting the chlorin evolved and provided or each provided with a heating coil, electric resist-ance, or other means adapted to heat the liquid at ornear the anode, and l may also With advantage provide each tube with a cooling,r coil jacket, or other cooling means arranged to cool the liquid'helow the anode so as furtherto prevent the possibilityY of the heated portion vof the liquid mixing' with the body of the electrolyte. A cathode or cathodes may be suit-v ably disposed in the cell, or the Walls of the cell may themselves form the cathode.

The process may if desired be Worked continuously and this will i'n fact be usually the case. For example the caustic soda solution formed in the electrolysis of sodium chlorid solution vmay be run oli' from the vessel and may be replaced by Jfresh chlorid solution run in to keep the electrolyte up to strength. ,The fresh chlorid solution may be run in through coils or cooling jackets before referred to, or direct into the anode tubes below the heated portion.

A single anode tube may be' used according to the invention but in practice a numbci oi them Will usually be employed in one cel l will proceed to describe some examples of apparatus constructed according to the invention, reference being had to Jdie accompanying diagrammatic drawings, in which,

Figure 1 is a diagrammatic section and Fig. 2 a diagrammatic plan -illustrating one form of apparatus, Fig. 3 a diagrammatic section illustrating another form and Fig. 4 a similar section illustrating a third form of apparatus according to the inyention.

In the form shown in `Figs. l and 2, L a represent anodes of carbon or other suitable material disposed in the upper portion of tubes b of glass, glazed earthenware, or other unattackable material, which extend into the cell c containing the solution to be electrolyzed, say brine, thev portion of the tube in which the anode is situated being above the level of the liquid in the cell 0,

which in the example shown is of iron or ot-her suitable metal and serves as the cathode. The tubes I) b are closed at top by wooden or other plugs e and are connected` by pipes j" to a pump or exhauster of any convenient kind for drawing away the :chlorin. lt will be seen that when the eXhauster is in action, the liquid will be drawn up into 4 the tubes around he anode above the liquid level in thev cell, as indicated in Fig. 1.

'g g are heating coils disposed around the anodes in the tubes and supplied with steam or other heating medium.

h z. represent cooling coils dis )osed below the anode and supplied with a ow of cold water or other cooling Huid.

The top of the cell between the anode tubes is shown as closed and provided with a pipe for leading away the hydrogen liberated liy the electrolysis. It desired a slight suction may be applied to facilitate the removal of the hydrogen.

In operation, when the cell is charged with brine or other liquid to be electrolyzed and the current is supplied to the cell, chlorin will be expelled from the iortions of the liquid around the anode by t e action of the heat (which may be such as to keep the liquor close to the anode near the boiling point) and will be drawn away by the eX- hauster, and it Willbe seen that although the liquid in the tubes communicates .freely with that in the cell the hot liquid cannot mix to any substantial extent with the cooler liquid below, so that the ehlorin is prevented or restrained from dissolving-in the velectrolyte and forming hypochlorate, chlorate,

or other undesired compounds. Thus an hydroxid solution'may be obtainedwhich is :tree or freer than hitherto fromv hypochlorites or other impurities. 1

For continuous working, the brine or liquid to be electrolyzed will be admitted in a regulated stream to the anode tubes'at a convenient point, for exemple through open Leccese ings B shown in dotted lines, and the iniowing current may then serve to cool the liquid below the anodes, Without using cooling coils. Or the liquid to be electrolyzed may be admitted through the cooling coils which may then discharge tubes.

ln the form of apparatus for continuous working illustrated in Fig'. 3, a number of anode tubes b such as above described are arranged so as to depend each into a well 'a' in the bottom of the cell, and are provided with heating coils .7 around the anodes and with cooling'coils iz, and chlorin pipes f f' as before. The electrolyte is supplied conJ vlinuously to the cell -to keep the bath up to strength, and here itself serves for cooling the liquid below the anodes. F or this purpose it is 'supplied in a suitably regulated stream to the funnel /c whence it flows through the cooling coils h .in the tubes b and issues at Z Z into the anode tubes or it may be into the. cell. Or if desired the liquid to be electrolyzed maybe admitted direct into the anode tubes through openings such as shown in dotted lines at- B without or with the employment ofA cooling coils supplied with a separate cooling liquid. The caustic soda solution formed runs ed from the cell by the overflow outlet m and the hydrogen escapes or is drawn away'by a. slight suction through the pipe p.

ln Fig. 8 theanodes and heating coils are disposed above the liquid in the cell as in Fig. l, and the exhauster will create sui cient suction to raise the electrolyte to a corresponding height in the tubes.

The Wells vi of the iron cell which forms the cathode may be formed of or lined with cement or other non-conducting material as indicated at n in order that hydrogen liberated in the elcctrolyzing operation may be kept away from the wells into which the tubes depend. I

ln some cases l may provide a heat insulating covering of asbestos or other heat insulating means around the heated portion of the anode tubes cspecial y if any part of this heated portion should lie below the level of the liquid outside in the cell. I'may also employ separate cathodes instead of usin the cell itself as a cathode. 'For example may employ annular cathodes, suoli as indicated in dotted lines at C, Fig. 1,'around the anode tubes and situated at a suitable level. Crthe cathode may consist lof wires, wire gauze, rods or the like of iron, nickel or other suitable metal. The lcathode ofwhatever kind, may be disposedor provided near the open lows? end ofthe anode tubes, but preferably around or not opposite the mouth of same, as otherwise the hydrogen liberated at the cathodewould' tend to rise into the anode tube and be dra wn away with the chlorin or gaseous anion. Such cathode may into the anode `for further treatment as required.

'anode in the tube and drawing oftl the chlorin. G is a gage for indicating the level of the liquid in the pipe ZJ. The brine is supplied by a pipe B terminating in a perforated coil B which discharges the brine in the tube Zi below the anode a. In this case the cathode consists of one or more wire gauze sheets K of nickel,

iron or .other suitable metal) (three .are

shown) disposed around the anode tube between same and the Wall of the cell and near the lower end of the anode tube. It will be understood that any desired number of anode tubes thus arranged and provided with heating coils, brine supply pipes and suction pipes may be employed in one cell, and the cathode sheets K may be common to all the anode tubes, being formed with holes to accommodate them, or separate cathode sheets may be employed for each anode tube. Instead of wire gauze sheets K Wires, rods or other suitable devices may be employed.

0 repsesents an overflow outletfor .the

electrolyte from the cell and the hydrogen can escape or be drawn away with slight suction by the pipe p. The hydroxid solution that passes away at O may be led awa It is to be understood that the forms of apparatus illustrated are given by way of example only, and that any other suitable arrangements may be employed based upon the application of combined heat and exhaust to a portion of electrolyte contained near the anode in an anode chamber communicating below with the electrolyte in the cell, without the interposition of a diaphragm.

By means of the invention in the electrolysis of sodium or potassium chloridv solutions, the chlorin liberated can be so eiliciently separated and removed from the electrolyte without necessity for quickly removing or .leading away the caustic liquor formed that it is possible to produce liquors or relatively high concentration in a practical and reliabltl manner. Moreover it is possible by the invention to work with a low expediture of current and with a high eiiiciency of cell.

It desired, carbonic acid gas may be led in to the electrolyte-in-the cell during the operation, so as to combine with the caustic soda or caustic potash produced by the elec,

trolysis and form sodium or potassium car.- bonate. `When the 'invention is applied to the electrolysis of solutions of sodium or potassium nitrate, similar apparatus to that above described may be employed. The nitrogen oxid or oxids liberated at the anode or anodes will be removed,and a/solution of caustic soda or caustic potash will be formed by the electrolysis. In this case also, carbonic acid gas may be led into the bath to form corbonate if so desired.

VVha-t I claim and desire to secure by Letters Patent is l. Process for the electrolysis in non-diaphragm cells of sodium or potassium chlorid or nitrate or other solutions which evolve a gaseous body at the anode, comprising the application of local heat and exhaust to a portion ofthe Velectrolyte contained near the anode in an anode chamber communicating belowv the anode with the electrolyte in the cell outside, the 'locally heated portion of the electrolyte being `drawn up around the anode above the level of the electrolyte in the cell by the exhaust substantially as described.

2. Process for the electrolysis in non-diaphragm cells of sodium or potassium chlorid or nitrate or other solutions which evolve a gaseous body at the anode, comprising the applicationl of local heat'and exhaust to av portionv of the electrolyte contained near the anode in an anode chamber communicating below. the anode with the electrolyte in the cell outside, the locally heated portion of the electrolyte being draw-n up around the anode. above the level of the electrolyte in the cell by the exhaust and cooling the solution below the locally heated portion for the purpose of confining the heat more closely to the portion of the solution in the immediate neighborhood of the anode, substantially as described.

Process for the electrolysis in non-diaphragm cells of sodium or potassium -chlorid or nitratev or other solutions which evolve a gaseous body at the anode, comprising the application of local heatA and exhaust toa portion,k of the (electrolyte contained near the anode in an anode chamber communicatf ing below the anode with the electrolyte in the cell outside, the locally heated portion of the electrolyte being'v drawn up around the anode above the level of the electrolyte in the cell by the exhaust, and cooling the sollition in the chamberbelow the' locally heated portion by means of `the liquid to be electrolyzed, substantially as and for the purpose described.

4. Process for. the electrolysis in non-diav phragm cells of sodium or potassium chlorid or nitrate` ohr other solutions which evolve a 'gaseous body at the anode, comprising the application of local heat and exhaustito a portion of the electrolyte contained near the above v'the .level .portionby delivering the liquid to be electrolyzed into the. anode chamber at a point below the anode,'substantially as described.

5. Apparatu tor use in. the electrolysis of solutions of the character referred to, comprising an anode-,containing-tube depending into. an electrolytic cell and open to the liquid in the cell at. a. point below the anode, ananode in said-tube, means for heating the electrolyte vin the neighborhood of the' anode, and means for4 removingthe gaseous anion and drawing up the locally heated portion of the electrolyte around the anode substantially as. described.

6. Apparatus for use in the electrolysis of solutions of the character referred. to, comprising an anode-containing tube depending into an electrolytic cell and open to the liquid in the cell at a point below the anode, an anodein said tube, heating coil for heating .the electrolyte in the neighborhood of the anode, and means for removing the gaseous anion and .drawing up, the locally heated-portion of the electrolyte around the anode substantially as described.

.7. Apparatusfor use in the electrolysis of solutions of the character referred to, comprising an anode-containing tube depending into an electrolytic cell and open to the liquid in the cell at -a point below the anode, an. anode in .said tube, means'for heating the electrolyte -in the neighborhood of the anode, and apump for removing the gaseous anion and drawingnp the locally heated portion of. thev electrolyte around the anode substantially' as described.

'8. Apparatnsfor use in-'the electrolysis of, solutions ofth'e character referred to, coniprising an anode-containing tube depending into an electrolytic cell and open to the liquid in the cell at a point below the anode, an anode insaid tube means for heating the electrolyte in the neighborhood of the anode, and means forfremoving the gaseous anion and drawing upsthe locally heated portion of .the electrolyte around the lanode and means for cooling the liquid in the anode tube at a point below the locally heated portion of.electrolyte substar'itially as described.

9. Apparatus for use inthe electrolysis of solutions of the character referred to, comprising an anode-containing tube depending into an electrolytic cell and open to the liquid in the cell ata point below the anode, an anode in said tube means for heating the electrolyte in the neighborhood of the anode, and means for removing the gaseous anion and drawing up the bottom, an

-and extending locally heated portion of the electrolyte around the anode and means for admitting the liquid to be electrolyzed to the anode tube at a. point below the locally heated portion of electrolyte substantially as described.

.10. Apparatus for use in the electrolysis of .solutions of the character referred to, comprising an anode-containing tube dei pending into the electrolytic cell and open at anode mounted in the said tube and extending downward, means for drawing up the electrolyte around the anode inl the tube and removing the gaseous anion, means for heating Lthe electrolyte around the anode, and a cathode surface near the open lower end of the anode tube, substantially as described.

l1. Apparatus for use in the electrolysis of solutions of the character referred to, comprising an anode-containing tube depending into the electrolytic cell and open at bottom, an anode mounted in the said tube downward means for draw- 'mg up the electrolyte around the anode in the tube and removing the gaseous anion, means for heatngthe electrolyte around the anode, and a cathode surface near the open lower end of the anode tube but not opposite the same,.substantiallyv.as described.

l2. Apparatus for use in the .electrolysis of solutions ofthe character referred to,

-1 comprising an anode-containing tube depending into the electrolytic cell and open at bottom, an anode mounted in the said tubev and extending downward means for drawing lup the electrolyte around the anode in the tube and removing the gaseous anion, means for heating the electrolyte around the anode, and a vcathode surface near the open lower end vof the anode tube, and a pipe for admitting liquid to be electrolyzed to the anode tube at a poi-ntbelow the anode.

13. Apparatus for use in the electrolysis of solutions of the character referred to, comprising an anode-containing tube depending into the electrolytic lcell and open at bottom, an anode mounted in the said llt) tube and extending downward, means for drawing up the electrolyte around the anode vmeans for heating the electrolyte around the anode, and a cathode of foraminous metal disposed'inear the (open lower end of the anode tube, substantially `as described.

14. Apparatus for use in the electrolysis of solutions of the character referred to, comprising an anode-containing tube depending into the electrolytic cell and open at bottom, an anode mounted in the `said tube and extending downward, means for drawing up the electrolyte around the anodeinl the tube and removing the gaseous anion, a heating coil for heating the electrolyte around theanode, a cathode of foraminous metal disposed around the anode tube near l theopen lower end thereof, and a pipe for admitting liquid to .be electrolyzed to the anode tube at a point below the anode, substantially as described.

15. Process for electrolyzing solutions by applying local heat and exhaust to the anolyte whereby to draw 01T the gases evolved at the anode.

16. Process for electrolyzing solutions by applying local heat and exhaust to the anolyte, .and cooling the electrolyte beyond the locally heated portion.

17; Apparatus for use in electrolyzing solutions, pending into the electrolyte, means for heating the anclyte in such chamber, and means for establishing suction r in -such chamber lutions,-comprising an anode chamber 'depending into the electrolyte, means for heating the anolytein `such chamber, means for establishing suction 1n such chamber above the solution for liftingthe anolyte and removing' the gaseous anion, and means for cooling the electrolyte beneath such' chamber.

In Witness whereof, I 'Ihave hereunto signed my name in the presence of two sub- CARTER WHITE.

- scribing witnesses. comprlsing an anodechamber de- I Witnesses: l y

- ROBERT MILTON SPEARPOINL THOMAS L. WHITEHEAD. v

Copies of this patent may 'he obtained fr ve cents each, by addressing the Commissioner of Patents,

- Washington, D. C.

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