Abstract: An autoelectrolytic hydrogen generator system constituted by one or a plurality of similar cells wherein a galvanic arrangement of magnesium and aluminum plates of sacrificial elements as anode; stainless steel as cathode and sea water as electrolyte, by its very nature is made to develop a voltage when connected in short circuit causing a current to flow within the system and hydrogen production of hydrogen in situ and on demand by the electrolytic action at one pole, the cathode, and additional hydrogen by the electrochemical reaction at the other pole, the anode. Surplus electric energy of the system applied to a optional electrolyzer will also be made to produce additional hydrogen at its two sacrificial aluminum electrodes.

Abstract: The present invention provides an electrolysis cell of the filter press type for the production of peroxy and perhalogenate compounds comprising alternatingly arranged cathodes and anodes provided with electrolyte feeds, wherein the cathodes (1) and anodes (2) consist of right parallelpiped-shaped hollow bodies between which are present frame-shaped seals (3) and which, via these seals (3), are connected together in a liquid-tight manner and insulated from one another to give a cell pile, the cathode hollow bodies (1) are liquid- and gas-permeable, the anode hollow bodies (2) possess, above and below a platinum layer, openings for the introduction and removal of the anolyte and the effective anode surface is formed by the platinum metal layer of a composite anode comprising a valve metal substrate and a platinum layer present thereon which is obtainable by the hot isostatic pressing of a platinum foil on to a valve metal carrier.

Abstract: A apparatus and method for the reduction and oxidation of constituents of a fluid is disclosed. The apparatus comprises a honeycomb-like structure of oxygen ion conducting ceramic having at least one passage. The passage is lined with a porous bipolar electrode and porous electrodes are formed outside the passage on the ceramic structure, the electrode in the passage being between the outside electrodes. If a voltage is applied to the outside electrodes, reducible and oxidizable constituents in a fluid passing over the passage electrode are oxidized and reduced. The capacity of the apparatus may be increased by increasing the number of passages/electrodes located between the outside electrodes.

Abstract: The present invention resides in part in a process for removing a multivalent metal ion contaminant such as can be found in an acidic waste water. The waste water may also contain one or more extraneous metals such as copper. This process aspect then more particularly involves the steps of (1) simultaneously reducing said multivalent contaminant to a lower valence state and said extraneous metal to a metal state, while at the same time inhibiting reoxidation of the multivalent contaminant to a higher valence state; and (2) removing the multivalent contaminant which has been inhibited from reoxidation.

Abstract: A method and device provide for the deionization and contaminants removal or degradation of aqueous liquids, particularly drinking water. The water is caused to flow in a first direction and while flowing it is treated so as to simultaneously effect deionization via electromigration and degradation or removal of the contaminants therein on particle surfaces. The water flows upwardly through a bed formed by a mixture of conductive and non-conductive particles, such as sand and graphite particles, with the particles of the bed being separated from an anode (mounted on one side of the bed) by an anionic membrane, and a cathode (mounted on the other side of the bed) by a non-ionic porous membrane. According to the invention the following ions and contaminants can be destroyed, or removed from, the water: calcium, magnesium, and other water hardening ions; sodium, iron, bacteria; chlorine, phenol, odor and color contaminants; and pesticides.

Abstract: An electrochemical cell having improved current efficiency and a method for electrochemically reacting a liquid electrolyte with a gas in an electrochemical cell. The cell has at least two electrodes separated by a cell separator wherein at least one of said electrodes is a porous, self-draining, gas diffusion electrode. In one embodiment of the invention, an electrolyte is flowed through said cell separator into a porous, self-draining electrode and simultaneously the electrode is fed with a mixture of a reactive gas and water or an electrolyte. In another embodiment of the invention in which the cell separator is an ion exchange permselective membrane, a mixture of a reactive gas and an electrolyte are fed to the porous, self-draining electrode. Preferably said porous, self-draining electrode is a cathode.

Abstract: An apparatus for the production of photoconductive components for use in electrophotography, including a coating tank that contains a certain amount of coating, the tank having a coating-supply opening, at a lower portion through which the coating is supplied to the tank, and a partition that is positioned between the inner wall of the tank and the outer wall of the electric conductor, whereby when an electric conductor to be coated is immersed in the coating and removed from the coating, occurrence of a turbulent flow of the coating in the vicinity of the electric conductor can be prevented.

Abstract: An electrolytic cell which comprises at least one anode and at least one cathode, an inlet channel through which liquor may be charged to the electrolytic cell, and an outlet channel through which liquor may be removed from the electrolytic cell, in which the outlet channel is operatively connected to the inlet channel, and in which the inlet channel comprises an ejector. The inlet and outlet channels may be formed in a unit made up of a plurality of shaped sheets, e.g. of electrically non-conducting plastics material, which together form the inlet and outlet channels.

Abstract: Electrolytic membrane cells for use in the production of alkalis are provided. A central anode reservoir chamber (1) has titanium (12) spread in sheets on opposite sides for electrolytic reaction with two cathode reservoir chambers (7) to form a monopolar cell. Each cathode has a porous tin sheet (8). The respective cathode chambers (7) are separated from the anode chamber (1) by diaphragm (6). Raw materials are fed through hydraulic pipes in the bottom of the cell and processed products are withdrawn from a chamber at the top of the anode chamber 1 where gases may accumulate.

Abstract: A storage, transportation and installation apparatus for ion exchange membranes for bipolar ion-exchange membrane chlorine cells which protects the ion-exchange membrane from the environment. The apparatus includes a container which allows the wet membrane, or a series of membranes separated by plastic sheets to lay flat inside the container protected by a plastic sheet. The container has a roller tension bar across one end which allows each membrane to be pulled out of the container directly into the area between the anode and cathode of the cell for mounting into place.

Abstract: An electrolytic cell, e.g., for the electrolysis of NaCl to produce chlorine and sodium hydroxide, has an improved operation control system, such system including a plurality of means for monitoring and controlling the flowstreams of inlet starting materials and/or outlet final products, the temperature of the electrolyte, the various reagent concentrations and the cell current, and such plurality of means being operably connected to a computing function which carries out corrective coherence calculations on certain of the parameters of electrolysis and adjusts the operation of the cell in response thereto.

Abstract: An apparatus and a method is disclosed for generating fluorine which has an improved efficiency by reducing the resistance between the electrodes and by reducing the chemical action on the electrodes through a design whereby the structure and positioning of the electrodes as well as the flow of electrolyte provide this reduction of the resistance. The shape of the cell unit constituting the electrode structure reduces the chemical action on the electrode by increasing the flow of electrolyte past the electrode structure.

Abstract: An electrolytic treatment method and a unit in which such a method is practiced are provided wherein heavy metal hydrous oxides are precipitated and recovered from a dilute waste stream to render the waste stream suitable for discharge. The waste stream is passed into the cathode chamber of an anion exchange membrane delineated electrolytic cell and subjected to high current density electrolysis to promote the formation of regular, noncompressible metal hydrous oxide crystals. Fluoride ion is added to the precipitate-containing waste stream, the precipitate is filtered and the clarified liquid waste stream is split so that a portion is discharged and a portion is recycled into the metal ion-containing waste stream for further treatment.

Abstract: Monopolar, bipolar, and hydrid filter press electrolytic cells for electrolytic processes utilizing a novel method of introducing and removing electrical energy are disclosed. The invention contemplates a novel low pressure, high surface contact area connecting means for joining the anode element and cathode element of electrode assemblies. The invention also contemplates a low pressure, high surface contact area contact of the current distributor member to the back plate.

Abstract: A combination electrolysis cell seal member and electrolysis cell frame cover member suitable for use as a gasket/cover member in an electrolytic cell of the filter press type. The gasket/cover member used for a filter press-type electrolytic cell includes two gasket/cover load-bearing sections integral with a peripheral frame cover section. The gasket load-bearing sections contains a first and second side. The first side contacts a electrolysis cell membrane member and the second side contacts an electrolysis cell frame member. The membrane is interposed between two electrolysis cell frame members each having a gasket/cover member secured thereto.

Abstract: A combination seal and membrane tentering member suitable for use in an electrolytic cell of the filter press type. The seal/tentering member for a filter press type electrolytic cell includes an inflatable gasket member interposed between a first and second insulator members, said insulator members having a recess defining a compartment adapted for receiving the inflatable gasket member, said insulator members interposed between a pair of cell frame flanges and a membrane member interposed between the insulator members. Aqueous alkali metal chloride solution may be electrolyzed in the electrolytic cell.

Abstract: An easily transportable electrolytic cell and associated processing apparatus is modularly constructed and supported in modular support sections that are easily separated and loaded onto transport vehicles for transport to distant remote sites where the electrolytic cell module and the processing apparatus module are reassembled and the apparatus is put into operation where the product chemical produced by the electrolytic cell is utilized.

Abstract: A porous diaphragm is disclosed for use in an electrochemical cell having at least one electrode characterized as porous and self-draining. The diaphragm provides a uniformity of flow of an electrolyte through the diaphragm even when exposed to varying electrolyte head pressures. The porous diaphragm of the invention has a plurality of layers of a microporous polyolefin film or a composite comprising the microporous polyolefin film and a support fabric resistant to deterioration upon exposure to an aqueous solution of an ionizable compound.

Abstract: A method and device for installing gasket members between two adjacent flat plate structures including removably attaching a gasket member on each side of a frame member to form a frame member and gasket member assembly, interposing the frame member and gasket member assembly between at least two cell frame members disposed adjacent to each other, and contacting the flat plate structures with the frame member and gasket member assembly such that the gasket members adhere diametrically opposed to each other on the flat plate structures. The frame member includes a rib portion around the outer periphery of the frame member, the rib portion forming a pair of shoulders opposite each other and facing away from each other and adapted for receiving a pair of gasket members such that the gasket members contact the rib portion and protrude a predetermined distance beyond the shoulder members.

Abstract: An apparatus in the form of a disk for the separation of oxygen from gases, or for the pumping of oxygen, uses a substantially circular disk geometry for the solid electrolyte with radial flow of gas from the outside edge of the disk to the center of the disk. The reduction in available surface area as the gas flows toward the center of the disk reduces the oxygen removal area proportionally to provide for a more uniform removal of oxygen.

Abstract: A chromium regeneration apparatus (10) is disclosed for regenerating spent chromium solution by oxidizing trivalent chromium to hexavalent chromium. The apparatus is provided with a tank (42) forming a reservoir full of spent chromium solution. A number of anode assembles (46) are supported on the tank within the reservoir with each assembly including two frame sections (70, 72) bolted together along their sides and bottom with two separate cation selective membranes (100, 102) secured therebetween. Membrane tensioners (104) are inserted between the membranes to separate them and urge them against the frame sections over openings in the frame sections to define an anode chamber. An anode and cathode are provided to a generate a current flow therebetween to regenerate the solution.

Abstract: The invention is a dampening device for use in a vertically disposed electrochemical cell unit of the type at least having: (a) a peripheral flange which defines at least one electrode chamber, said peripheral flange having a upper, substantially horizontally disposed flange portion, a lower substantially horizontally disposed flange portion, and two disposed side flange portions; and (b) at least one outlet port passing through the upper horizontally disposed flange portion or through one of the two vertical side flange portions or through the lower flange portion and connecting the exterior of the cell with the electrode chamber.

Abstract: A process control system for a filter press membrane electrochemical cell is provided that utilizes a microcomputer for multi-tasking functions to concurrently execute four programs to control the cell operation and self-correct out-of-tolerance conditions or shut cell operation down if not corrected within the allotted time period. A core process control program intercommunicates with a timer program, an alarm monitoring program and at least one sequence program in the process control system.

Abstract: An electrolytic cell which comprises at least one anode and at least one cathode, an inlet channel through which liquor may be charged to the electrolytic cell, and an outlet channel through which liquor may be removed from the electrolytic cell, in which the outlet channel is operatively connected to the inlet channel, and in which the inlet channel comprises an ejector. The inlet and outlet channels may be formed in a unit made up of a plurality of shaped sheets, e.g. of electrically non-conducting plastics material, which together form the inlet and outlet channels.

Abstract: The present invention relates to an electrochemical process for deoxygenating deionized water utilizing a membrane electrolyzer and optionally a catalytic reactor, characterized in that operation is carried out at ambient temperature avoiding the need for the addition of substances, dangerous for the health of the operators, able to pollute the enviornment or cause undesired increase of the concentration of dissolved salts.

Abstract: A filter press type electrolytic cell for continuous operation with renewable sacrificial electrodes. Said device enables cells of the filter press type to be fitted with a sacrificial electrode formed from metallic particles or generally from particles which are consumed during the electrolysis, and which can be continuously renewed.The modified cells according to the invention can be used successfully for electro-organic processes.

Abstract: In this process for electrically separating the electrolyte-bearing main from the electrolyte spaces of an electrochemical cell pile, the electrolyte is passed via drop sections directly from the main into the electrolyte space or directly from the electrolyte space into the main.

Abstract: An electrolytically ionized water forming apparatus including: a plurality of electrolysis devices, each comprising an electrolysis vessel having a cathode and an anode opposed to each other and an electrolysis diaphragm partitioning the space between both of the electrodes into a cathode chamber and an anode chamber; water supply channels each disposed on one side and two discharge systems of an ionized alkaline water discharge channel in communication with the cathode chamber and an acidic water discharge channel in communication with the cathode chamber each disposed on the other side of the plurality of electrolysis devices respectively; the plurality of electrolysis devices being connected in series in a plurality of stages such that only one of the two ionized water discharge channels of the electrolysis device at a certain preceeding stage constitutes a water supply channel to the electrolysis device at the succeeding stage.

Abstract: The present invention relates to an electrolyzer comprising at least an intermediate electrodic structure interposed between two electrodic end-structures, a separate on each side of the intermediate electrodic structure, device for impressing electrolysis current to the electrolyzer and means for feeding electrolytes to and withdrawing electrolysis products from the electrolyzer compartments. The intermediate electrodic structure comprises a current conducting and distributing core (1) of at least one highly conductive metal sheet; a series of substantially parallel, projecting ribs (2, 10) provided or not onto both surfaces of said core (1); a liner (3) on each side of the core (1) and made of a corrosion resistant metal. These liners (3) are formed by cold- or hot-pressing to fit to the ribs (2, 10) in case core ribs are provided, or have parallel ribs (10') fixed thereto in case core (1) has no ribs. The liners (3) have peripheral projecting flanges (4) parallel to the liners.

Abstract: Process/apparatus for electrolytically oxidizing solutions of ionic compounds features the electrolytic oxidation of such solutions in a first anode compartment of an electrolytic cell, said electrolytic cell further comprising a second anode compartment, a cathode compartment, and a pair of cationic membranes respectively separating said cathode compartment from said first and second anode compartments; transferring a portion of said solution electrolytically oxidized in said first anode compartment to said second anode compartment and there continuing the electrolytic oxidation thereof; and then recovering product of electrolytic oxidation from said second anode compartment.

Abstract: The invention relates to an electrowinning cell for extracting metals in powder form from solutions, and simultaneously oxidizing the solution. The cell is characterized by radially extending electrodes comprising mutually alternating anodes and cathodes; by a diaphragm which delimits separate anode and cathode chambers, of which the cathode chamber forms an outer space; and a stirring means arranged in the anode chamber and operative to ensure a large flow of electrolyte across the anode surfaces. The base of the cathode chamber is preferably conical in shape.

Abstract: In accordance with the present invention an electrochemical cell unit is comprised of:an anolyte compartment, catholyte compartment separated from each other by a pair of close spaced ionic (cationic/or anionic) membranes which together with a foraminous non-structural spacer therebetween form an intermediate compartment between the anolyte and catholyte compartments, respectively, which upon application of hydraulic pressure to the anolyte and/or the catholyte compartments reduce the cross membrane distance of the intermediate compartment to a minimum distance.

Abstract: An electrolytic cell of the filter-press type which comprises plate-like anodes, cathodes, and gaskets of an electrically-insulating material, and an ion-exchange membrane between each anode and adjacent cathode to form in the cell a plurality of anode compartments and cathode compartments, the gaskets, and optionally the anodes and cathodes, each containing apertures therein which form headers from which liquors may be charged to the anode and cathode compartments of the cell and to which products of electrolysis may be removed from the anode and cathode compartments of the cell, and in which the gaskets, and optionally the anodes and cathodes, each comprise an aperture therein which together form a compartment lengthwise of the cell which is in communication only with the anode compartments of the cell, or which is in communication only with the cathode compartments of the cell, and which serves as a balancing header.

Abstract: An electrolytic silver refining process in which crude silver is anodically dissolved and refined silver is cathodically deposited and at the same time accompanying metals are selectively extracted from the spent electrolyte and separately cathodically deposited after having been transferred into an aqueous phase and the regenerated electrolyte stripped of accompanying metals is recycled to the refining process and in which further the spent electrolyte is anodically enriched in silver and accompanying metals are cathodically deposited from the aqueous phase in a joint electrolysis step.

Abstract: An electrolyzer for electrolysis of water comprises a series of cells each including a substantially open porous anode plate and a substantially open porous cathode plate disposed on either side of and in contact with a solid electrolyte membrane. First and second flow passages extend through the cell, with the first flow passage comprising concentrically aligned bores extending through the center of the cathode plate, the anode plate and the membrane, with the bore in the cathode plate being fitted with an annular sealing gasket. The second flow passage also comprises concentrically aligned bores extending through the cathode plate, the anode plate, and the membrane, with a bore in the anode plate being fitted with an annular sealing gasket. A seal is provided at the outside perimeter of the cathode plate, to prevent the escape of fluid containing hydrogen therefrom. During operation, a source of water is connected to the first flow passage and water is driven into the cell.

Abstract: A tunnel protected electrochemical device features channels fluidically communicating between manifold, tunnels and cells. The channels are designed to provide the most efficient use of auxiliary power. The channels have a greater hydraulic pressure drop and electrical resistance than the manifold. This will provide a design with the optimum auxiliary energy requirements.

Abstract: An electrolytic cell comprising at least one anode and at least one cathode and pipework for charging liquor to the electrolytic cell and pipework for discharging liquor from the electrolytic cell, in which at least one of the pipeworks is made in part of an electrically non-conducting material and which also comprises an electrically conducting electrode material positioned in the pipework, e.g. a section of pipework made of a metallic electrode material, and in which the electrode material is electrically connected directly or indirectly to the anode or cathode by means of an electrical connection external of the electrolytic cell.

Abstract: In a stacked plurality of similar electrolysis cells, each cell having an overhead gas for accumulating gasses produced thereby, the apparatus of the present disclosure includes a shaped transition tube connected to each cell. Inlet liquids and outlet gasses with their respective liquids to be fed and removed through a pair of respective adjacent headers.

Abstract: The present invention is a circular structural frame particularly suitable for use in an electrochemical cell. The frame comprises an organic plastic or metallic member with a plurality of horizontally and vertically spaced-apart shoulders protruding outwardly from opposing generally spherical anolyte and catholyte surfaces of the plastic member. Each of the shoulders annularly encircles and supports an electrically conductive insert extending from an exterior face of a shoulder on the catholyte surface of the plastic member, through the plastic member, to an exterior face of a shoulder on the anolyte surface of the plastic member.An electrically conductive substantially completely hydraulically impermeable anolyte cover is matingly affixed to the anolyte surface of the plastic member and adapted to minimize contact between the anolyte and the plastic member. The anolyte cover is resistant to the corrosive effects of the anolyte.

Abstract: An apparatus used in high pressure electrolytic cell operation which allows a cell to be operated at high pressures while providing balanced interface pressures between circulating liquids and gases. Each liquid and gas compartment in the cell is connected to a holding tank. Gas pressure in the holding tank is allowed to build up to the pressure required for cell operation before it is released. Positive displacement pumps circulate liquids through the cell at a pressure equal to the pressure of gases contained in the holding tanks. Gases are back-pressured into the gas compartments of the cell at a pressure equal to the pressure of the gases contained in the holding tanks thereby balancing the pressures of gases and liquids in the cell while allowing for circulation of the liquids.

Abstract: An electrolytic cell is provided with electrodes which are inserted within electrode frames with internal flow conduits and which are formed by metallurgical bonding, and the use of adhesives and an electrical resistance lowering conductive compound between contact surfaces.

Abstract: An electrode chamber unit intended for use in an electrochemical cell including at least one porous percolating electrode in the form of a bed of electrically conductive particles, e.g. of graphite.

Abstract: An electrolytic cell of the filter press type comprising a plurality of anodes, cathodes and gaskets, and ion-exchange membranes positioned between each adjacent anode and cathode to form in the cell a plurality of anode compartments and cathode compartments, the cell having two inlet headers from which electrolyte may be charged to the anode compartments of the cell and from which liquors may be charged to the cathode compartments of the cell, and two outlet headers from which products of electrolysis may be removed from the anode compartments and cathode compartments of the cell, the cell being provided with a common chamber in communication with each of the anode compartments and/or a common chamber in communication with each of the cathode compartments, said chamber(s) being provided with means for recirculating liquors to the anode compartments and/or to the cathode compartments, and said chamber(s) being in communication with the outlet headers from the anode compartments and/or the outlet headers from

Abstract: A multi-cell electrolyzer comprising a plurality of unit cells, each of which is composed of an anode chamber containing an anode and a cathode chamber containing a cathode and a cation exchange membrane for partitioning said unit cell into said anode chamber and said cathode chamber, and each of which is adapted to have an internal pressure maintained at a level higher than the atmospheric pressure in operation of the electrolyzer, said plurality of unit cells being arranged in series and adapted to be energized through a plurality of current lead plates, and rigid multi-contact electrically conductive means provided between the adjacent unit cells and/or between each current lead plate and the unit cell adjacent thereto, thereby establishing electrical connection between the adjacent unit cells and/or between each current lead plate and the unit cell adjacent thereto.

Abstract: An electrode comprising a base member having on at least one face thereof a plurality of first major channels closed at one end and provided at the other end thereof with means for feeding liquors thereto, a plurality of second major channels closed at one end and provided at the other end thereof with means for removing liquors therefrom, and a plurality of minor channels of smaller cross-section than the major channels and positioned between the first major channels and the second major channels and providing means for liquors to flow between the first major channels and the second major channels. Also, an electrolytic cell comprising such an electrode.

Abstract: Disclosed is an electrolysis process which is characterized by carrying out the electrolysis of an aqueous alkali metal halide solution while supplying a cathode liquor into a cathode compartment formed between a cation exchange membrane positioned substantially horizontal and a cathode plate of gas-liquid impermeability, with which the membrane is wetted, then a mixed stream of the cathode liquor and cathode gas being removed from the cathode compartment.Also disclosed is an electrolytic cell which is comprised of an upper anode compartment and a lower cathode compartment partitioned by a cation exchange membrane positioned substantially horizontal, said anode compartment having therein substantially horizontal anodes and an anolyte solution inlet and outlet, and said cathode compartment having a cathode plate with gas-liquid impermeability and a cathode liquor inlet and an outlet of a mixed stream of the cathode liquor and cathode gas.

Abstract: A filter press electrochemical cell with an improved fluid distribution system for even distribution of electrolyte between cell units when connected in parallel, and from side to side and across the thickness of reaction chambers in individual cells regardless of whether parallel or series flow connection is used. Each preferred cell unit comprises two electrodes and a fluid distributor plate having at least two first holes therein and channel portions including diverging walls connecting these holes with opposite sides of a central cell opening in each plate. Preferred configurations of the triangular-shaped channel opening thereby formed permit distribution of fluid without complicating barrier structures or other constrictions in the fluid path such as used in prior art cells. Preferred and alternate cell arrangements and configurations are disclosed.

Abstract: An improved electrolytic reactor is provided with a sealed enclosure subdivided into separate solution chambers for an anolyte and for a catholyte by the interposition of an electrically insulating septum with a microporous matrix. The microporous membrane, or septum, permits the controlled passage of ionic species but prevents the gross intermixing of the separate electrolytes in respective contact with the cathode and the anode of the reactor. At least one of the chambers defined on either face of the microporous septum is filled with electrically conductive particulate material--stainless steel balls in one embodiment--acting as extensions of the electrode in that chamber, so as to increase the electrically charged, stable surface available for electrolytic mass transfer.

Abstract: A process for electrolysis of an electrolyte, e.g. aqueous alkali metal chloride solution in an electrolytic cell comprising a plurality of anodes and cathodes and separators positioned between adjacent anodes and cathodes to form in the cell a plurality of anode compartments and cathode compartment, the process comprising charging the electrolyte to the anode compartments, electrolyzing the electrolyte, and removing the products of electrolysis from the anode and cathode compartments, the anodes and cathodes comprising an electroconducting electrocatalytically-active portion affixed to a frame member of an electrically non-conducting plastics material, and the frame members being bonded directly or indirectly to each other. Also an electrolytic cell for use in the process.

Abstract: There are provided integrated modules for use in electrodialysis devices, which modules comprise a plurality of unit cells each of which consists of a cation specific membrane, a spacer and an anion specific membrane, said membranes being sealed along the edges of the cell, a spacer being provided between consecutive cells serving for sealing along the edges, an outlet being provided for the brine, outlets of individual cells being arranged as common outlet, a plurality of unit cells being confined in a frame which is provided with an outlet for said cells, each frame being provided with sealing means towards the next such frame. There are also provided electrodialysis stacks comprising a plurality of such modules.