US2951026A - Mercury cathode electrolytic cell - Google Patents

Mercury cathode electrolytic cell Download PDF

Info

Publication number
US2951026A
US2951026A US667165A US66716557A US2951026A US 2951026 A US2951026 A US 2951026A US 667165 A US667165 A US 667165A US 66716557 A US66716557 A US 66716557A US 2951026 A US2951026 A US 2951026A
Authority
US
United States
Prior art keywords
plates
shaft
mercury
cathode
shell
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US667165A
Other languages
English (en)
Inventor
Messner Georg
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
De Nora SpA
Original Assignee
Oronzio de Nora Impianti Elettrochimici SpA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Oronzio de Nora Impianti Elettrochimici SpA filed Critical Oronzio de Nora Impianti Elettrochimici SpA
Application granted granted Critical
Publication of US2951026A publication Critical patent/US2951026A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
    • C25B11/02—Electrodes; Manufacture thereof not otherwise provided for characterised by shape or form
    • C25B11/033—Liquid electrodes
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
    • C25B9/30—Cells comprising movable electrodes, e.g. rotary electrodes; Assemblies of constructional parts thereof
    • C25B9/303—Cells comprising movable electrodes, e.g. rotary electrodes; Assemblies of constructional parts thereof comprising horizontal-type liquid electrode
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
    • C25B9/70—Assemblies comprising two or more cells

Definitions

  • a further object is to provide an electrolysis apparatus having a number of superimposed horizontal mercury cathodes.
  • Another object is to provide a horizontal mercury cathode electrolysis cell having a number of superimposed electrolysis compartments.
  • Still another object is to provide a horizontal mercury cathode electrolysis cell having a relatively large vertical dimension and a relatively small cross-sectional area.
  • a further object is to provide a method for electrolyzing electrolytic solutions with a mercury cathode, whereby recombination of electrolytic products is prevented and proper adjustment of the distance between electrodes is possible.
  • Fig. 1 illustrates a sectionalplan view of one tray of my preferred apparatus taken along the line A--A of Fig. 2 of a cell having horizontal plates.
  • Fig. 2 represents a sectional side view of the same cell as shown in Fig. 1, taken along the line BB.
  • Fig. 3 illustrates a cell embodying circular plates sloping downward towards the center, and anon-vertical axis.
  • Fig. 4 illustrates a cell showing the enclosed top and base of the shell, having a non-vertical axis and sloping plates, and which embodies a different structure for the withdrawal of mercury amalgam.
  • the cell is composed of a cylindrical shell 16 with its axis disposed vertically. Along the axis of shell 16 there is a hollow shaft 6.
  • the electrolysis compartments C in the cell are arranged horizontally, one above the other, throughout the height of shell 16.
  • Each electrolysis compartment is made up of a circular fiat plate 2 attached to shaft 6 and having a rim 3 at its periphery, a set of fixed anodes 9 provided with bus bar connections 1i) arranged above the cathode plate and grouped radially around hollow shaft 6, electrolyte feed pipe 11 with a distributor 12, a mercury feed pipe 5, and a weir l.
  • the general set-up of the electrolytic cell can be arranged so as to obtain an assembly of unipolar type, that is a cell in which all of the cathodes are at the same potential with respect to one another, which is'also true of the anodes.
  • the cathode plates can be all connected to the negative line through the common driving shaft 6.
  • the movement of shaft 6 causes the plates 2 to rotate within the shell 16 about the axis of the shell.
  • weir 1 comprising a fiat strip of flexible and electrically non-conductive material, is arranged radially slightly above each plate so that there is a small space between the bottom of the Weir and the horizontal surface of the plate.
  • the weir 1 is fixed While the plate surface moves tangentially underneath it, and the function of the Weir is to allow the mercury stream that flows from the feed pipe 5 to build up a pool 4 of mercury on the plate, which is contained by the brim 3 of electrically nonconductive material which surrounds plate 2.
  • a space is left between anodes 9a and 9b in which the mercury pool 4 is maintained.
  • the plates are illustrated in Fig. 1 as rotating clockwise so that the plate moves into the pool formed by a hold back means such as weir l.
  • the plates could, of course, rotate in the opposite direction, in which case the amalgam would be introduced on the opposite side of weir 1 from that shown in Fig. 1.
  • a particularly suitable way of using cathode plates of conical shape consists of tilting the shaft 6 slightly from the vertical direction as shown in Figs. 3 and 4, until one generatrix in each conical surface lies horizontal, or nearly so, While the opposite generatrix acquires a slope forming with respect to the horizontal plane an angle twice as large as the tilt of the shaft from the vertical direction.
  • a mercury pool 4 will form in a restricted area on the horizontal 'gcneratrix plane of trays 2 since the mercury feed pipe 5 is located over the horizontal portion of this plane and the plates 2 are surrounded by a brim 3 of electrically non-conductive material.
  • the whole plate surface passes under the pool and under the rows of fixed anodes during a complete revolution so that the amalgam layer, which is adhering to the metal plate surface and is concentrated with sodium discharged in the cathodic process coming into the pool, is replaced with an outgoing layer of dilute amalgam.
  • the upper surfaces of the cathodic plates are made of a conducting metal, as for example steel, while the lower surfaces must be electrically non-conductive and chemically resistant to the electrolyte as well as to the anodic product such as chlorine.
  • the lower surface may be any suitable plastic or hard rubber material or a plastic or hard rubber coating on a steel plate.
  • the hollow shaft 6 is made of sufficiently thick and electrically conductive material, so as to afford sufiicient mechanical rigidity and act as an electric current lead to be connected with the negative line.
  • Another embodiment of the present invention consists of using a hollow shaft 6 and providing it with an inner diameter adequately large to form a reaction chamber for the decomposition of the amalgam that is discharged into it through one or more of the slots from the pool 4.
  • mercury enters the pool 4 on the periphery, passes through it in radial direction and finally is discharged through the slots in the shaft 6 into the amalgam decomposition chamber formed in the shaft cavity.
  • the anodes 9 of any suitable and conventional material, such as graphite, which is particularly suitable for the electrolysis of alkali chlorides, or a lead-silver alloy for the electrolysis of a sodium sulphate solution.
  • graphite which is particularly suitable for the electrolysis of alkali chlorides, or a lead-silver alloy for the electrolysis of a sodium sulphate solution.
  • a suitable diaphragm is required between each cathode and each corresponding set of anodes.
  • the anodes 9 can rotate with the cathodes. However, it is more advantageous to keep them at rest.
  • a particularly convenient arrangement consists of conveying the electric current to the outer periphery of each anode through the connection 10.
  • Such arrangement beside providing a liberal spacing for the required number of electric connections, gives a further advantage in that the electric current is thus conveyed through the largest cross-section as presented by the anodes on their peripheral sides. This is most advantageous with graphite material, in view of its rather poor electrical conductivity, since by such arrangement it is possible to keep the voltage drop throughout the anode'material down to a minimum value.
  • Fig. 4 shows another embodiment of the present invention in which means are provided for a particularly simple method of adjusting the spacing between anodes and cathodes without requiring the electrolysis current to be interrupted. This is obtained by the axial shifting of the'system composed of the shaft 6 and cathodes 2. In this way it is possible to keep the electrodes spacing, and therefore also the cell voltage,at a practically constant value during the electrolysis process, irrespective of anode consumption.
  • the fresh electrolyte is fed into the cell over each rotating plate by means of pipes 11, which pass through the cylindrical shell 16 of the electrolysis cell and extend to near the outer wall of the shaft 6, where they join with ring-shaped distributors 12 provided with a plurality of holes 13.
  • Theelectrolyte distributing system is made of material chemically resistant to the electrolyte and chlorine.
  • the depleted electrolytic solution leaves the space between the electrodes at the periphery thereof and then flows upward or downward along the shell 16, until it reaches the base 20 of the cell, and leaves the shell through outlet 21 which leads to an overflow not shown.
  • Fig. 4 shows another particularly convenient embodiment of the invention, in which the system formed by the shaft -6 and the cathode plates 7 is composed of an assembly of equal elements 14 upon one another. Specially V-shaped spigot-and-socket joints are provided between each section and the next one in the assembly, such as illustrated in Fig. 4 showing a cross-sectional View through the shaft center-line which can usually be employed as drain passageways 15a for the amalgam from the electrolysis compartment into the hollow shaft, and which form hydraulic seals.
  • the same constructional principles as disposed above can he usually employed also for a bi-polar type assembly.
  • all the cathode plates are electrically insulated from one another and each one is connected by a suitable electrical conductor with the next underlying anode.
  • all paths through the electrolyte that might provide a shunt for the current between the positive and the negative pole are made as narrow and as long as possible, for instance by baflling devices.
  • a horizontal 120,000 amp. cell of conventional-design, which produces about 4 short tons of chlorine per day requires a floor space of about 700 sq. ft. including aisles.
  • a cell of the same capacity but of the type as described and based on this invention would require less than 250 sq. ft. of floor space. 7
  • An electrolytic apparatus having a mercury cathode, which comprises a hollow rotating cylindrical shaft dispo sed substantially vertically, a plurality of circular plates attached to said shaft externally along its axis, anodes and supporting means therefore above each of said plates, a shell enclosing said shaft and plates, means in said shell for introducing an electrolytic solution and mercury onto each of said plates, and conduit means communicating with said plates through said shaft for withdrawing amalgam from each of said plates.
  • cathode plates are electrically insulated from one another, each cathode plate being connected to the adjacent anodes, to form a system of series-connected bipolar cells.
  • An electrolytic apparatus having a mercury cathode, which comprises a hollow rotating cylindrical shaft disposed substantially vertically, a plurality of circular plates attached to said shaft externally along its axis, a rim around each plate, anodes and supporting means therefor above each of said plates, a shell enclosing said shaft and plates, means in said shell for introducing an electrolytic solution and mercury onto each of said plates, an electrically non-conductive narrow, flexible strip disposed radially and slightly above each horizontal plate to form a weir to retain a mercury pool over said plate and spread the mercury over said rotating plate, and conduit means communicating with said plates through said shaft for withdrawing amalgam from each of said plates.
  • An electrolytic apparatus having a mercury cathode, which comprises a hollow rotating cylindrical shaft disposed substantially vertically, a plurality of flat circular plates attached to said shaft externally along its axis and perpendicular to said axis, anodes and supporting means therefor above each of said plates, a shell enclosing said shaft and plates, means in said shell for introducing an electrolytic solution and mercury onto each of said plates, and conduit means communicating with said plates through said shaft for withdrawing amalgam from each of said plates.
  • An electrolytic apparatus having a mercury cathode which comprises a hollow cylindrical shaft disposed substantially vertically, a plurality of circular plates attached to said shaft externally along its axis, the upper surfaces of said plates having a hollow conical shape, anodes and supporting means therefor above each of said plates, a shell enclosing said shaft and plates, means in said shell for introducing an electrolytic solution and mercury onto each of said plates, and conduit means communicating with said plates through said shaft for Withdrawing amalgam from each of said plates.
  • An electrolytic apparatus having a mercury cathode which comprises a hollow cylindrical shaft, a plurality of circular plates attached to said shaft externally along its axis, the upper surfaces of said plates having a hollow conical shape, anodes and supporting means therefor above each of said plates, a shell enclosing said shaft and plates, means in said shell for introducing an electrolytic solution and mercury onto each of said plates, and conduit means communicating with said plates through said shaft for withdrawing amalgam from each of said plates, wherein said hollow shaft is tilted until one generatrix of the conical plate is substantially horizontal.
  • An electrolytic apparatus having a mercury cathode, which comprises a hollow cylindrical shaft disposed substantially vertically, a plurality of circular plates attached to said shaft externally along its axis, anodes and supporting means therefor above each of said plates, said anodes being stationary, disposed radially around said hollow shaft and provided with electrical connections at their peripheral sides, a shell enclosing said shaft and plates, means in said shell for introducing an electrolytic solution and mercury onto each of said plates, and conduit means communicating with said plates through said shaft for withdrawing amalgam from each of said plates.
  • An electrolytic apparatus having a mercury cathode, which comprises a plurality of identical circular plates having short segments of a hollow cylinder of the center thereof, said segments being adapted to permit the circular plates to fit in a superimposed position whereby a hollow cylindrical shaft disposed substantially vertically is formed, said shaft containing slots forming a hydraulic seal between said segments for the withdrawal of amalgam, anodes above said plates, a shell enclosing said shaft and plates, and means in said shell for introducing an electrolytic solution and mercury onto each of said plates.
  • An electrolytic apparatus having a mercury cathode, which comprises an upright cylindrical shell, a hollow shaft along the axis of said shell, a plurality of horizontal electrolysis compartments spaced externally along the axis of said shaft, each compartment comprising a circular cathode plate, anodes and supporting means therefor above said plate, and means to supply an electrolytic solution and mercury to the top of said plate, and conduit means communicating with said plates through said hollow shaft for withdrawing amalgam from each electrolytic compartment.
  • a cathode element comprising a circular plate structure having a segment of a hollow cylinder at the center thereof, said cylinder segment being adapted on the top and bottom edges to fit against the cylinder segments of identical cathode elements in such a manner that slots for the passage of mercury and amalgam remain, whereby an assembly of said elements may be made to comprise a hollow shaft having a plurality of circular plates externally along the axis thereof and slots through said shaft at each plate for the passage of mercury and amalgam.
  • a cathode element comprising a segment of a hollow cylinder having a circular plate surrounding it and perpendicular to the axis thereof, the upper edge of said segment being grooved and the lower edge being tongued in such a manner that the upper edge will fit into the lower edge of an identical element and the lower edge will fit into the upper edge of another identical element, said upper and lower edges of the elements being further adapted to leave slots which form hydraulic seals between elements for the passage of fluids through the cylinder walls of the hollow shaft formed by an assembly of said cathode elements.
  • a method for the electrolysis of electrolytic solutions which comprises the steps of introducing the solution to be electrolyzed into a plurality of superimposed horizontal, circular, rotating electrolytic cells at a point near the center thereof, introducing mercury into said cells at a point on the periphery thereof, withdrawing amalgam through slots in a hollow central drive shaft for said cells, and withdrawing gaseous products and depleted electrolytic solution from the periphery of said cells.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrolytic Production Of Metals (AREA)
US667165A 1956-06-28 1957-06-21 Mercury cathode electrolytic cell Expired - Lifetime US2951026A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE822665X 1956-06-28

Publications (1)

Publication Number Publication Date
US2951026A true US2951026A (en) 1960-08-30

Family

ID=6743907

Family Applications (1)

Application Number Title Priority Date Filing Date
US667165A Expired - Lifetime US2951026A (en) 1956-06-28 1957-06-21 Mercury cathode electrolytic cell

Country Status (5)

Country Link
US (1) US2951026A (en(2012))
BE (1) BE558408A (en(2012))
DE (1) DE1020965B (en(2012))
FR (1) FR1178004A (en(2012))
GB (1) GB822665A (en(2012))

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3068165A (en) * 1959-12-01 1962-12-11 Oronzio De Nora Impianti Eiett Mercury cathode electrolytic cell

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB852597A (en) 1957-06-01 1960-10-26 Asahi Garasu Kabushiki Kaisha Apparatus and method for the electrolysis of alkali metal salts
US3445374A (en) * 1964-09-05 1969-05-20 Tsuyoshi Ishimatsu Alkali chloride electrolytic mercury cells

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US318932A (en) * 1885-05-26 tbippe
GB190010925A (en) * 1900-06-15 1901-05-18 William Phillips Thompson Improvements in Apparatus and Method of Decomposing Alkaline and other Amalgams.
US789721A (en) * 1904-02-29 1905-05-16 Decker Mfg Company Electrolytic apparatus.
US1569606A (en) * 1924-02-06 1926-01-12 Ashcroft Edgar Arthur Apparatus for electrolyzing fused salts of metals and recovering the metals and acid radicles

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US318932A (en) * 1885-05-26 tbippe
GB190010925A (en) * 1900-06-15 1901-05-18 William Phillips Thompson Improvements in Apparatus and Method of Decomposing Alkaline and other Amalgams.
US789721A (en) * 1904-02-29 1905-05-16 Decker Mfg Company Electrolytic apparatus.
US1569606A (en) * 1924-02-06 1926-01-12 Ashcroft Edgar Arthur Apparatus for electrolyzing fused salts of metals and recovering the metals and acid radicles

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3068165A (en) * 1959-12-01 1962-12-11 Oronzio De Nora Impianti Eiett Mercury cathode electrolytic cell

Also Published As

Publication number Publication date
DE1020965B (en(2012))
GB822665A (en) 1959-10-28
BE558408A (en(2012))
FR1178004A (fr) 1959-05-04

Similar Documents

Publication Publication Date Title
US3984303A (en) Membrane electrolytic cell with concentric electrodes
US3707454A (en) Anode and base assembly for electrolytic cells
CA1043732A (en) Electrochemical cell
US4048047A (en) Electrochemical cell with bipolar electrodes
GB1460357A (en) Vertical diaphragm electrolytic cells
JPS627275B2 (en(2012))
US3930981A (en) Bipolar electrolysis cells with perforate metal anodes and baffles to deflect anodic gases away from the interelectrodic gap
US2987463A (en) High amperage diaphragm cell for the electrolysis of brine
EP3286356A1 (en) Electrode assembly, electrode structures and electrolysers
US3291889A (en) Dielectric interrupter
US2194443A (en) Anode for electrolytic cells
US2951026A (en) Mercury cathode electrolytic cell
JO2116B1 (en) Electric analyzer for halogen gas production
US2799643A (en) Electrolytic cell
US3803016A (en) Electrolytic cell having adjustable anode sections
US3785951A (en) Electrolyzer comprising diaphragmless cell spaces flowed through by the electrolyte
US3689384A (en) Horizontal mercury cells
US2970095A (en) Method and apparatus for electrolytic decomposition of amalgams
US3796648A (en) Electrolytic cell having self-aligning anodes
US3832300A (en) Bipolar diaphragm electrolyzer with cathode waves in horizontal plane
ES412801A1 (es) Una cuba electrolitica.
US2762765A (en) Methods and apparatus for electrolytic decomposition
US3923614A (en) Method of converting mercury cathode chlor-alkali electrolysis cells into diaphragm cells and cells produced thereby
US2368861A (en) Electrolytic cell
US2916425A (en) Apparatus for the electrolysis of alkali metal salts and process therefor