[go: up one dir, main page]

US2824054A - Process and apparatus for the manufacture of solutions of alkali metal hydroxides - Google Patents

Process and apparatus for the manufacture of solutions of alkali metal hydroxides Download PDF

Info

Publication number
US2824054A
US2824054A US479704A US47970455A US2824054A US 2824054 A US2824054 A US 2824054A US 479704 A US479704 A US 479704A US 47970455 A US47970455 A US 47970455A US 2824054 A US2824054 A US 2824054A
Authority
US
United States
Prior art keywords
amalgam
cathode
compartment
alkali metal
reaction chamber
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
US479704A
Other languages
English (en)
Inventor
Rene A Crabbe
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.)
Solvay SA
Original Assignee
Solvay SA
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 Solvay SA filed Critical Solvay SA
Application granted granted Critical
Publication of US2824054A publication Critical patent/US2824054A/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
    • C25B1/00—Electrolytic production of inorganic compounds or non-metals
    • C25B1/01—Products
    • C25B1/34—Simultaneous production of alkali metal hydroxides and chlorine, oxyacids or salts of chlorine, e.g. by chlor-alkali electrolysis
    • C25B1/36—Simultaneous production of alkali metal hydroxides and chlorine, oxyacids or salts of chlorine, e.g. by chlor-alkali electrolysis in mercury cathode cells
    • C25B1/42—Decomposition of amalgams

Definitions

  • PROCESS AND APPARATUS FOR THE MANUFACTURE-OF SOLUTIONS OF ALKALI METAL HYDROXIDES Filed Jan. 4, 1955 United States Patent ice PROCESS AND APPARATUS FOR THE MANUFAC- TURE 0F SGLUTIONS 0F ALKALI METAL HY- DROXIDES Ren Al Crabbe, Boitsfort-Brussels, Belgium, assignor to Solvay & Cie., Brusseis, Belgium, a Belgian company Application January 4, 1955, Serial No. 479,704 Claims priority, application Belgium January 6, 1954 11 Claims. (Cl.
  • This invention relates to a process for the manufacture of solutions of alkali metal hydroxides by the decomposition of am-algams obtained by electrolysis of the corresponding salts such as for example chlorides or sulphates of sodium or potassium.
  • the decomposition of the 'amalgams is carried out in apparatus whose functioning can be compared to that of a so called denuder cell in which the amalgam forming the anode is decomposed in contact with the cathode constituted, for example, by a set of successive graphite grids.
  • the apparatus for the decomposition of amalgams is often called a denuder.
  • the cathode layer is. formed by elements which have the form of a grid whose graphite bars form the cathode elements proper. These bars can be in direct contact with the amalgam to be decomposed; they can likewise be kept at some distance from the amalgam layer, but in this case the shortcircuit of the denuder is safeguarded by contact pieces, preferably metallic ones, which are immersed in the mercury. These graphite bars lose finally their activity of decomposition even if they have not become white or have not acquired a metallic look. This loss of activity can be explained by the fact that, in the decomposition of amalgam, not only the ions of the alkali metal are liberated and react with water, but also, by the fact 2,824,054 Patented Feb. 18, 1958 that under the action of the generated electric current, metallic contaminations of the amalgam decompose on the cathode bars and modify the electric characteristics of same.
  • the process of the invention comprises the moving of the set of grids from one end to the other end of the denuder at a rate which will be in accordance with the rate of the activity loss of the graphite, removing one grid at said last end and placing of a fresh or regenerated grid into the space which has become free in the denuder.
  • this displacement can be carried out in a discontinuous manner, but it is possible to provoke a slow but continuous displacement without transgressing the scope of the invention.
  • the grids removed from the end of the denuder are then regenerated in known manner, such as for example, by steaming, or by applying mechanical means suitable for the cleaning of surfaces, etc.
  • the new process is applicable to amalgam of alkali metals however obtained.
  • the working. of the denuder has to be interrupted when it is necessary to replace the set of worn anodes, even if the said cell comprises a device for compensating for the wear of the anodes during working.
  • the continuous working of the denuder could be unlimited when the same denuder receives the amalgam from two or more cells. This uninterrupted working may also be ensured by coupling the denuder according to the invention with an electrolytic cell or" the type described in Belgian specification 499,224 of Nov. 7, 1950, according to which the anodes are successively replaced in proportion as they wear down.
  • the invention also comprises a device for carrying out the process in a denuder of the horiontal type substantially consisting in providing the cell with a compartment for introducing fresh cathodes and a compartment for removing the least active cathodes, the compartment placed on the side of the inlet of the concentrated alkali metal amalgam, being advantageously provided with a guide which prevents the contact between the cathode and the concentrated amalgam.
  • the denuder comprises a tank 1, an inlet 2 for the amalgam, an outlet 3 for the mercury, an outlet 4 for the lye, and a hydraulic mercury guard 5.
  • the tank is closed by a lid 6 provided with gas outlets 7.
  • the compartment of decom osition of amalgam is delimited by two weirs 3 and d which are gas-tight and immersed in the solution of alkali metal hydroxide It
  • the compartment for the decomposition is situated between two other compartments: the first of which 11 serves for introducing fresh cathodes and the second one 12 which serves for removing the cathodes which have become inactive.
  • the introduction of fresh cathodes is carried out while the denuder is working, and it is therefore necessary to avoid any contact between these cathodes and the amalgam at the moment of their introduction.
  • the compartment for introducing the cathodes is pro vided with a slide 13 which keeps the fresh cathodes above the amalgam and conducts them directly into the decomposition compartment.
  • the compartment for removing cathodes may similarly be provided with a slide 20.
  • a fresh cathode 14 is introduced the whole series or train of cathodes 15 moves forward by the range of one cathode, after the oldest one 16 has previously been removed in order to allow the translation of the other cathodes along the amalgam 17.
  • the compartment for introducing new cathodes and the compartment for withdrawing used cathodes are provided with hinged lids 18 and 19.
  • the apparatus comprises also an inlet (not shown) for introducing fresh water into the denuder.
  • the drawing is not limitative, as any design of denuders of the horizontal type may be used if it can be fitted with an entrance and exit compartment for the cathodes, provided that the compartment at the side of the concentrated amalgam is furnished with a device avoiding the contact between the fresh cathode and the concentrated amalgam as long as the said cathode remains outside the decomposition compartment.
  • the said entrance compartment may be situated also at the other end of the apparatus.
  • a denuding cell of the horizontal type for continuously producing an alkali metal hydroxide solution of high and substantially constant strength by the decomposition of the corresponding alkali metal amalgam comprising, in combination, an elongated substantially horizontal trough having a sole for supporting the amalgam as it flows through the cell, means defining an inlet compartment at a first end of said trough, means defining an outlet compartment at a second end of said trough, and a main reaction chamber between said compartments, a plurality of graphite cathode elements disposed in laterally adjacent relationship extending from said inlet compartment to said outlet compartment in a position for electrically-conductive contact with said amalgam, said inlet and said outlet compartments each being of a size sulficient to accommodate a cathode element outside of said main reaction chamber, and said means defining said compartments permitting movement of said cathode elements to and from said compartments and said main reaction chamber, at least said inlet compartment being provided with guide means for supporting a cathode element outside of said main reaction chamber,
  • a denuding cell of the horizontal type for continuously producing an alkali metal hydroxide solution of high and substantially constant strength by the decomposition of the corresponding alkali metal amalgam comprising, in combination, an elongated substantially horizontal trough having a sole for supporting the amalgam as it flows through the cell, means defining an inlet compartment at a first end of said trough, means defining an outlet compartment at a second end of said trough, and a main reaction chamber between said compartments, a plurality of graphite cathode elements disposed in laterally adjacent relationship extending from said inlet compartment to said outlet compartment, said cathode elements being positioned to be in direct contact with said amalgam, said inlet and said outlet compartments each being of a size sufficient to accommodate a cathode element outside of said main reaction chamber, and said means defining said compartments permitting movement of said cathode elements to and from said compartments and said main reaction chamber, at least said inlet compartment being provided with guide means for supporting a cathode element outside of
  • a denuding cell of the horizontal type for continuously producing an alkali metal hydroxide solution of high and substantially constant strength by the decomposition of the corresponding alkali metal amalgam comprising, in combination, an elongated substantially horizontal trough having a sole for supporting the amalgam as it flows through the cell, means defining an inlet compartment at a first end of said trough, means defining an outlet compartment at a second end of said trough, and a main reaction chamber between said compartments, a plurality of graphite cathode elements disposed in laterally adjacent relationship extending from said inlet compartment to said outlet compartment, and electrically-conducting contact pieces for separating said cathode elements from the amalgam but maintaining them in electrically-conducting contact therewith, said inlet and said outlet compartments each being of a size sufiicient to accommodate a cathode element outside of said main reaction chamber, and said means defining said compartments permitting movement of said cathode elements to and from said compartments and said main reaction chamber
  • said cell comprising, in combination, an elongated substantially horizontal trough having a sole for supporting the amalgam asfit flows through the cell, means defining an inlet compartment at a first end of said trough, means defining an outlet compartment at a second end of said trough, and a main reaction chamber between said compartments, a plurality of graphite cathode elements disposed in laterally adjacent relationship extending from said inlet compartment to said outlet compartment in a position for electrically-conductive contact with said amalgam, said inlet and said outlet compartments each being of a size sufficient to accommodate a cathode element outside of said main reaction chamber, and said means defining said compartments permitting movement of said cathode elements to and from said compartments and said main reaction chamber, said main reaction chamber having a cover and said compartments having independent covers whereby the end compartments may be opened without opening the main reaction chamber, at least said inlet compartment being
  • a denuding cell of the horizontal type for continuously producing an alkali metal hydroxide solution of high and substantially constant strength by the decomposition of the corresponding alkali metal amalgam comprising, in combination, an elongated substantially horizontal trough having a sole for supporting the amalgam as it flows through the cell, means defining an inlet compartment at a first end of said trough, means defining an outlet compartment at a second end of said trough, and a main reaction chamber between said compartments, a plurality of graphite cathode elements disposed in laterally adjacent relationship extending from said inlet compartment to said outlet compartment in a position for electricallyconductive contact with said amalgam, said inlet and said outlet compartments each being of a size sufiicient to accommodate a cathode element outside of said main reaction chamber, and said means defining said compartments permitting movement of said cathode elements to and from said compartments and said main reaction chamber, said inlet compartment and said outlet compartment being provided with guide means for supporting a cathode element outside of
  • a denuding cell of the horizontal type for continuously producing an alkali metal hydroxide solution of high and substantially constant strength by the decomposition of the corresponding alkali metal amalgam comprising, in combination, an elongated substantially horizontal trough adapted to contain the solution at a predetermined level and having a sole for supporting the amalgam as it flows through the cell and a top, means defining an inlet compartment at a first end of said trough, means defining an outlet compartment at a second end of said trough, and a main reaction chamber between said compartments, a plurality of graphite cathode elements disposed in laterally adjacent relationship extending from said inlet compartment to said outlet compartment in a position for electrically-conductive contact with said amalgam, said inlet and said outlet compartments each being of a size sutficient to accommodate a cathode element outside of said main reaction chamber, and said means defining said compartments permitting movement of said.
  • said means defining the inlet compartment being a weir extending from the top of the trough to a point below said level whereby to be immersed in the solution, at least said inlet compartment being provided with guide means for supporting a cathode element outside of said main reaction chamber and holding it out of all contact with said amalgam until it is introduced into the main reaction chamber, and said guide means in said inlet compartment being constructed to guide said cathode element automatically from a position substantially above the amalgam to the position occupied by said cathode elements in the main reaction chamber.
  • a denuding cell of the horizontal type for continuously producing an alkali metal hydroxide solution of high and substantially constant strength by the decomposition of the corresponding alkali metal amalgam comprising, in combination, an elongated sub stantially horizontal trough having a sole for supporting the amalgam as it flows through the cell, means defining an inlet compartment at a first end of said trough, means defining an outlet compartment at a second end of said trough, and a main reaction chamber between said compartments, a plurality of graphite cathode elements disposed in laterally adjacent relationship extending from said inlet compartment to said outlet compartment in a position for electrically-conductive contact with said amalgam, said inlet and said outlet compartments each being of a size sufiicient to accommodate a cathode element outside of said main reaction chamber, and said means defining said compartments permitting movement of said cathode elements to and from said compartments and said main reaction chamber, said inlet compartment being provided with guide means for supporting a cathode element
  • a denuding cell of the horizontal type for continuously producing an alkali metal hydroxide solution of high and substantially constant strength by the decomposition of the corresponding alkali metal amalgam comprising, in combination, an elongated substantially horizontal trough adapted to contain the solution at a predetermined level and having a sole for supporting the amalgam as it flows through the cell and a top, means defining an inlet compartment at a first end of said trough, means defining an outlet compartment at a second end of said trough, and a main reaction chamber between said compartments, a plurality of graphite cathode elements disposed in laterally adjacent relationship extending from said inlet compartment to said outlet compartment in a position for electrically-conductive contact with said amalgam, said inlet and said outlet compartments each being of a size sufficient to accommodate a cathode element outside of said main reaction chamber, and said means defining said compartments permitting movement of said cathode elements to and from said compartments and said main reaction chamber, said means defining the outlet compartment being a

Landscapes

  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrolytic Production Of Metals (AREA)
US479704A 1954-01-06 1955-01-04 Process and apparatus for the manufacture of solutions of alkali metal hydroxides Expired - Lifetime US2824054A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
BE327267X 1954-01-06

Publications (1)

Publication Number Publication Date
US2824054A true US2824054A (en) 1958-02-18

Family

ID=3867801

Family Applications (1)

Application Number Title Priority Date Filing Date
US479704A Expired - Lifetime US2824054A (en) 1954-01-06 1955-01-04 Process and apparatus for the manufacture of solutions of alkali metal hydroxides

Country Status (7)

Country Link
US (1) US2824054A (fr)
BE (1) BE525535A (fr)
CH (1) CH327267A (fr)
DE (1) DE946620C (fr)
FR (1) FR1117036A (fr)
GB (1) GB764403A (fr)
NL (2) NL193762A (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3663385A (en) * 1968-08-30 1972-05-16 Kureha Chemical Ind Co Ltd Alkali salt electrolysis by mercury process

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH235756A (de) * 1943-05-05 1944-12-31 Krebs & Co Elektrolytische Zelle mit Quecksilberkathode.
US2551248A (en) * 1944-02-09 1951-05-01 Solvay Apparatus for the decomposition of alkali amalgams

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH235756A (de) * 1943-05-05 1944-12-31 Krebs & Co Elektrolytische Zelle mit Quecksilberkathode.
US2551248A (en) * 1944-02-09 1951-05-01 Solvay Apparatus for the decomposition of alkali amalgams

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3663385A (en) * 1968-08-30 1972-05-16 Kureha Chemical Ind Co Ltd Alkali salt electrolysis by mercury process

Also Published As

Publication number Publication date
DE946620C (de) 1956-08-02
NL193762A (fr)
NL85436C (fr)
GB764403A (en) 1956-12-28
FR1117036A (fr) 1956-05-15
BE525535A (fr)
CH327267A (fr) 1958-01-31

Similar Documents

Publication Publication Date Title
US3676315A (en) Production of sodium chlorate
US2817631A (en) Refining titanium alloys
MX2020012087A (es) Mejora en la refinacion electrolitica de cobre.
FR2430988A1 (fr) Procede pour effectuer la circulation en cascade de l'electrolyte dans les cellules electrolytiques pour la production de chlore et de base alcaline
FR2397470A1 (fr) Procede d'electrolyse de saumures de chlorure de metal alcalin
GB880838A (en) Improvements in or relating to electrolytic cells
US4087339A (en) Electrowinning of sulfur-containing nickel
US2824054A (en) Process and apparatus for the manufacture of solutions of alkali metal hydroxides
US2975111A (en) Production of titanium
PL82400B1 (fr)
US4090939A (en) Electrolytic diaphragm cell
US3268427A (en) Electrolysis of alkaline chloride solutions
US3595614A (en) Amalgam decomposition
US3344049A (en) Method of producing lithium
US3082159A (en) Production of titanium
US2704743A (en) Mercury cathode electrolysis apparatus
US2417259A (en) Electrolytic process for preparing manganese and manganese dioxide simultaneously
US2624702A (en) Separation of nickel from cobalt containing solutions
US2448262A (en) Metal cleaning
US2949412A (en) Mercury-cell electrolysis of sodium chloride brine
US3382163A (en) Method of electrolytic extraction of metals
US3134729A (en) Electrolysis of sodium sulfate
US1191799A (en) Process of producing alkali metals.
US2313338A (en) Electrolytic zinc dust process
US3006824A (en) Production of metals by electrolysis