Abstract: In forming an electrolytic water, pure water or ultra-pure water is added to at least one solid supporting electrolyte selected from the group consisting of oxalic acid, ammonium oxalate, ammonium formate, ammonium bicarbonate, and ammonium tartrate to prepare a solution saturated with the supporting electrolyte. The solution containing the supporting electrolyte is subjected to hydrolysis to obtain an anodic water and a cathodic water.

Abstract: An oxygen-depolarised cathode for aqueous hydrchloric acid electrolysis membrane cells is described, the cathode being in contact with the membrane and capable of preventing the release of hydrogen into oxygen even at the highest current densities. Hydrochloric acid may also be of technical grade with a concentration limited to 15%, whereas the operating temperature must not exceed 60° C. The cathode contains a mixture of rhodium sulphide and a metal of the platinum group applied in a single layer or alternatively applied separately in two distinct layers.

Abstract: An apparatus and method for plating a metal onto a substrate. The apparatus generally includes an anode electrode disposed in the electrochemical cell and a cathode electrode disposed opposite the anode electrode in the electrochemical cell. The apparatus further includes an electrode lid having more than one aperture disposed between the anode electrode and the cathode electrode, the apertures configured to electrically connect the cathode electrode and the anode electrode.

Abstract: Improved methods and devices for the synthesis of hydrogen peroxide employing redox catalysts in a gas diffusion electrode or membrane electrode assembly in a semi-chemical/electrochemical system for the production of high purity, stable, usually acidic, aqueous solutions of peroxide at high conversion efficiencies without requiring organic solvents.

Abstract: A biocidal solution is provided having a pH of from 5 to 7 and an available free chlorine content of from 500 to 1,000 ppm. A method is also provided for producing the biocidal solution in an electrolytic cell or cells having anode and cathode chambers which produce respective anolyte and catholyte solutions, wherein the biocidal activity of the biocidal solution is conferred on the solution primarily in the anode chamber. The method includes the steps of supplying the cell or cells with a solution having a salt concentration of 2.0 to 5.0 g/L, such that the solution passes through the anode chamber at a flow rate per anode surface area of 1.25×103 to 2.75×103 L hr−1m−2, and applying current to the cell or cells sufficient to produce a biocidal solution having the above free chlorine content and pH.

Abstract: An apparatus comprising an electrolyte cell, an anode, and a porous rigid diffuser. The electrolyte cell is configured to receive a substrate to have a metal film deposited thereon. An anode is contained within the electrolyte cell. A porous rigid diffuser is connected to the electrolyte cell and extends across the electrolyte cell. The diffuser is positioned between a location that the substrate is to be positioned when the metal film is deposited thereon and the anode.

Abstract: A plating cell base design that utilizes a single connection that provides both fluid communication and electrical communication to the cell. The design eliminates many of the components previously necessary to effectuate fluid and electrical seals. With fewer connections, material cost is reduced, reliability is enhanced, and downtime is reduced.

Abstract: A galvanic cell system (50) in fluid communication with a dewatering system (40) of an inhibited oxidation scrubber (20) removes an oxidation catalyst, i.e., solution phase iron (98), from the process liquor (42) produced by the dewatering system (40) and replaces the iron (98) with magnesium (104) in an oxidation-reduction reaction. An electrolytic cell system (154) in fluid communication with a dewatering system (144) of a forced oxidation scrubber (128) removes an oxidation inhibitor, i.e., solution phase aluminum (174), from the process liquor (146) produced by the dewatering system (144) and replaces the aluminum (174) with iron (170) in an oxidation-reduction reaction. The process liquor (42, 146) is subsequently returned to the scrubber (20, 128) with the solution phase metal (98, 174) selectively removed, thereby enhancing the scrubbing efficiency of the scrubber (20, 128).

Abstract: The present invention provide a method and an apparatus for detecting anions in water which does not require replacement of ion exchange resins and the like and can perform precise measurement at low cost in a simple operation.

Abstract: The invention relates to an apparatus for purifying fluids comprising at least one electrochemical cell having a cathode (3), an anode (5) and an electrolyte (7), said cathode (3) comprising a metal complex, ML, where M represents a metal and L represents an organic or inorganic ligand, said complex being capable of forming the hydroxyl radical by a reaction wherein the metal in the complex is oxidised and acquires an additional positive charge, said anode (5) creating positive ions and electrons, said electrolyte (7) allowing the transfer of a positive charges, said cathode being arranged such that the fluid to be purified can come into contact with the metal complex on the cathode. The invention also provides a related electrode and a related electrochemical cell as well as a corresponding method for purifying fluids.

Abstract: The present invention generally provides an apparatus and method for neutralizing an acid in a plating solution. The apparatus generally includes a plating cell having an anolyte compartment containing an anolyte and a catolyte compartment containing a catolyte, wherein the anolyte compartment has an anolyte inlet and an anolyte drain and the catolyte compartment has a catolyte inlet and a catolyte drain, and a cell membrane disposed in the cell between the anolyte compartment and the catolyte compartment, wherein the membrane is selective to hydrogen ions and copper ions. The apparatus further includes a catolyte storage unit in fluid communication with the catolyte inlet and an electrochemical device in fluid communication with the catolyte chamber, the electrochemical device being configured to receive a portion of aged catolyte solution and correct a catolyte concentration.

Abstract: An electrochemical cell capable of operating in pressure differentials exceeding about 2,000 psi, using a porous electrode. The porous electrode comprises a catalyst adsorbed on or in a porous support that is disposed in intimate contact and fluid communication with the electrolyte membrane.

Abstract: One embodiment of a method of operating an electrochemical cell system comprises: flowing supply water to an anode electrode of an electrolysis cell, applying a first current density to the electrolysis cell, electrolyzing the supply water at the anode electrode wherein hydrogen ions and a first portion water migrate to a cathode electrode of the electrolysis cell, collecting the first portion of water in a chamber in fluid communication with the cathode electrode, monitoring a first portion water level in the chamber, when the first portion water level attains a first selected level, decreasing the supply water flow to the anode electrode a sufficient amount to draw the first portion water from the chamber to the anode electrode, and electrolyzing the first portion water.

Abstract: A waste water treatment device is provided in which removal of phosphorus and removal of nitrogen can efficiently be carried out and a decrease in size of the device and a decrease in cost can be achieved. The waste water treatment device includes a waste water treatment chamber; at least one set of electrodes disposed so that at least a part of the electrodes are immersed in waste water in the waste water treatment chamber, at least one of said electrodes dissolving out, by electrolysis, iron ions or aluminum ions for precipitating and removing phosphoric acid ions in waste water; a power source for supplying an electrolytic current to the set of electrodes; a control section for controlling the power source; and a metallic catalyst which is disposed in the vicinity of at least one of the sets of electrodes and which effects a denitrifying reaction with hydrogen in waste water.

Abstract: A method of carrying out an electro-chemical treatment, especially for electro-chemically coating conducting parts or parts made to be conducting, in a container which is filled with an electrolyte and in which there are arranged two electrodes which are connected to a constant voltage source, has the parts, while being treated in the electrolyte, being continuously re-arranged in the rotating basket. The parts are cathodically switched by a hub of the basket. The electrolytic solution is pumped in a cycle through the container, with the container remaining sealed so as to be gas-tight.

Abstract: An electrolytic bath has a waterway converter that allows the ionized water outlets to discharge the same species of ionized water even if the polarity of the produced ionized water at the polar chamber has been reversed in order to prohibit the formation of the scale at the electrode. The waterway converter includes a cylinder-shaped valve housing and a cylindrical-bar shaped valve body wherein the valve body is rotated in accordance with the inversion of polarity at the chamber in such a way that the central linking pipe and linking pipe are alternatively linked to the alkaline and acid ionized water outlets.

Abstract: A method for operating an electrolysis cell at a range of pressures and current densities, the cell having an ultrathin composite membrane, preferably comprising an expanded polytetrafluoroethylene base material impregnated with a hydrogen conducting ionomer. The resulting membrane is unexpectedly durable and efficient when used in an electrolysis cell operating at high membrane pressure differentials, thereby allowing greater cell current densities and efficiency.

Abstract: Solid membranes comprising an intimate, gas-impervious, multi-phase mixture of an electronically-conductive material and an oxygen ion-conductive material and/or a mixed metal oxide of a perovskite structure are described. Electrochemical reactor components, such as reactor cells, and electrochemical reactors are also described for transporting oxygen from any oxygen-containing gas to any gas or mixture of gases that consume oxygen. The reactor cells generally comprise first and second zones separated by an element having a first surface capable of reducing oxygen to oxygen ions, a second surface capable of reacting oxygen ions with an oxygen-consuming gas, an electron-conductive path between the first and second surfaces and an oxygen ion-conductive path between the first and second surfaces. The element may further comprise (1) a porous substrate, (2) an electron-conductive metal, metal oxide or mixture thereof and/or (3) a catalyst.

Abstract: The invention provides an ion exchange membrane electrolyzer ensuring a satisfactory circulation of electrolyte, high electrolytic efficiency and great ridigity. An anode chamber partition in a flat sheet form is joined to a cathode chamber partition in a flat sheet form. An electrode retainer member in a sheet form is joined to at least one partition at a belt-like junction. A projecting strip with an electrode joined thereto is located between adjacent junctions. A space on an electrode surface side of the electrode retainer member defines a path through which a fluid goes up in the electrode chamber, and a space that spaces away from the space defines a path through which an electrolyte separated from a gas at a top portion of the electrode goes down.

Abstract: Reactor for carrying out electrochemical reactions with an electrode and a counter-electrode are known, whereby the electrodes are separated form one another by a capillary gap. Such reactors do not comprise a homogeneous flow rate distribution in the capillary gap which can thus lead to a reduction of selectivity and of local temperature increases. In addition, high ohmic resistance requires the use of conducting salts. The aim of the invention is to provide a reactor in which the voltage drop in the electrolyte is minimized and which can be better optimized over a short resistance time distribution. To this end, the capillary gap comprises at least one channel as a reaction chamber having a height less than or equal to 200 &mgr;m. According to the inventive method, the volume flow of the educt current is measured such that the flow of the educt current is laminar over the length of the channel having a height less than or equal to 200 &mgr;m.

Abstract: An anode as a workpiece, and a cathode opposed to the anode with a predetermined spacing are placed in ultrapure water. A catalytic material promoting dissociation of the ultrapure water and having water permeability is disposed between the workpiece and the cathode. A flow of the ultrapure water is formed inside the catalytic material, with a voltage being applied between the workpiece and the cathode, to decompose water molecules in the ultrapure water into hydrogen ions and hydroxide ions, and supply the resulting hydroxide ions to a surface of the workpiece, thereby performing removal processing of or oxide film formation on the workpiece through a chemical dissolution reaction or an oxidation reaction mediated by the hydroxide ions. Thus, clean processing can be performed by use of hydroxide ions in ultrapure water, with no impurities left behind on the processed surface of the workpiece.

Abstract: The object of the present invention is to provide a thin and light electrochemical device using a solid polymer electrolytic film, which is capable of maintaining its steady performance for a long time even at a high humidity condition and a process for preparing the same. The device comprises inserting and pressuring the jointed electrochemical device 10 between a pair of pressing plates 30 and 31, wherein the jointed electrochemical device 10 is obtained by jointing the anode and the cathode having a catalytic layer on a base substrate of conductive porous material to both sides of the solid polymer electrolytic film, and wherein the pressing plates have the opening part having an area smaller than an electrochemical reaction part formed by facing the anode and the cathode.

Abstract: A production apparatus of hypochlorite solution includes an electrolytic cell having a housing the interior of which is subdivided by a partition membrane to form therein anode and cathode chambers, and positive and negative electrodes respectively disposed within the anode and cathode chambers and opposed to each other through the partition membrane, wherein the positive and negative electrodes are applied with DC voltage to effect electrolysis of chloride solution such as sodium chloride solution or potassium chloride solution supplied into both the anode and cathode chambers, and wherein acid water and alkaline water respectively produced in the anode and cathode chambers are mixed to produce hypochlorite solution.

Abstract: The present invention relates to a unique electrochemical cell stack which employs an electrically conductive pressure pad. The pressure pad is composed of material compatible with the electrochemical cell environment and is disposed on the high pressure side of the membrane assembly, in intimate contact with the high pressure side screen pack.

Abstract: The present invention provides an ozone generation and delivery system that lends itself to small scale applications and requires very low maintenance. The system preferably includes an anode reservoir and a cathode phase separator each having a hydrophobic membrane to allow phase separation of produced gases from water. The hydrogen gas, ozone gas and water containing ozone may be delivered under pressure.

Abstract: A process for producing improved alkaline water includes filtering potable source water to remove selected particles and then purifying the filtered water. Selected alkaline minerals are added to the purified water, with the resulting mineralized water being then electrolyzed to produce streams of acidic water and alkaline water, the alkaline water having a pH within the range of 9-10, a TDS range of 22-240 ppm (parts per million) and alkalinity in the range of 12-216 ppm.

Abstract: The present invention is directed to an apparatus and method for deionization and hydrogen fuel production in a fuel generation mode, and electricity production in a power generation mode. In one embodiment, a capacitive deionization (CDI) device receives water and electrical energy to produce deionized water that is transferred to a proton electrode membrane electrolysis (PEME) device to produce hydrogen fuel by electrolysis. A storage system receives the hydrogen. The hydrogen is transferred from the storage system to a proton electrode membrane fuel cell (PEMFC) device that produces electrical energy. In another embodiment, the PEME and the PEMFC are functionally combined in a unitary regenerative fuel cell (URFC). In still another embodiment, a humidification unit and the CDI are functionally combined. In yet another embodiment, a CDI, URFC and the humidification unit are combined in a single unitary assembly.

Abstract: Disclosed herein are electrochemical cell systems, pressure control systems, and methods for operating those systems. In one embodiment, the electrochemical cell system comprises: an electrochemical cell stack; a phase separation apparatus in fluid communication with the electrochemical cell stack; a water discharge in fluid communication with the phase separation apparatus; a first flow control device and a second flow control device disposed in fluid communication between the phase separation apparatus and water discharge; and a control device in operable communication with a sensor, the first flow control device, and the second flow control device. In one embodiment, the pressure regulating system comprises: means for generating hydrogen; means for sensing a liquid level within a phase separation apparatus disposed in fluid communication with the means for generating.

Abstract: Disclosed is a process for recovery of cyanide and metals from a liquor containing complexes of cyanide and metal typically generated by a metallurgical or industrial process. The process involves electrochemical dissociation of the metal-cyanide complex and electrowinning of the metal while free cyanide generated in the process is recovered in a membrane treatment step for re-use in a metallurgical process utilising it. An electrochemical apparatus, which may be used in the process, forms a further aspect of the invention. A membrane process alone, for separation of cyanide, from liquors containing cyanide complexes is a further aspect of the invention.

Abstract: The invention disclosed relates to an electrochemical process for decreasing high levels of organic contaminants in metal plating baths. The process involves breaking down the organic contaminants in an electrochemical cell by electrochemical oxidation. The electrochemical cell includes an anode comprising an active material which is stable at low (acid) pH and at the high electrical potential required to break down the organic contaminants by oxidation. Typical examples of such anodes include a valve metal substrate coated with doped tin dioxide, lead dioxide, or platinum-based materials, the latter in some instances being coated on a high surface area valve metal substrate.

Abstract: A new cell assembly for semiconductor wafer electroplating in the plated-side-up configuration utilizes a narrow passageway around the perimeter of the wafer through which solution is forced so as to provide the laminar flow needed for effective Damascene copper plating. In addition, use of a cylindrical insulating cell wall whose inside diameter matches that of the wafer area being plated avoids overplating of the wafer periphery. Anode isolation in a compartment separated via a solution transport barrier prevents introduction of particulates and holds anolyte in place during wafer changes. This cell assembly is readily amendable to automated wafer plating.

Abstract: A method and apparatus for purifying aqueous effluent streams to reduce chemical oxygen demand thereof, where the method comprises direct oxidation of water-soluble organic material in an electrochemical cell that incorporates stainless steel electrodes, whose stability and lifetime are enhanced by inclusion of circulating metal chips.

Abstract: An electroforming apparatus comprising a container unit for storing the plating solution, a cathode part placed in the container unit and for holding an object to-be-plated and an anode part placed in the container unit face-to-face with the cathode part, wherein a current-conductive opening of the anode part is formed to have an area larger than that of a current-conductive opening of the cathode part.

Abstract: A method and apparatus for water treatment. The method comprises supplying an oxygen-containing gas to cathode 6 to yield hydrogen peroxide, supplying an inorganic acid to anode 5 through an acid solution addition opening 4 to yield an oxidation product, e.g., hypochlorous acid, and using both the hydrogen peroxide and oxidation product thus generated to treat a liquid to be treated. The atmosphere around the cathode surface is kept neutral to acidic due to the acidity of the coexisting oxidation product to thereby inhibit the deposition of metal hydroxides.

Abstract: A hydrogen source system delivers a controlled fuel stream to applications, using wicking to control the contact between a mixture of NaBH4, NaOH and H2O and a hydrolyzing catalyst to create a feedback mechanism to automatically maintain a constant pressure production supply of hydrogen. A small compact device packaged for storage, the system operates in any orientation and is mobile. The system is a small portable packaged hydrogen generator for small fuel cells to power applications that are currently powered by batteries. These packaged devices have higher energy per unit mass, higher energy per unit volume, are more convenient for energy users, environmentally less harmful, and less expensive than conventional power sources.

Abstract: An electroplating apparatus prevents anode-mediated degradation of electrolyte additives by creating a mechanism for maintaining separate anolyte and catholyte and preventing mixing thereof within a plating chamber. The separation is accomplished by interposing a porous chemical transport barrier between the anode and cathode. The transport barrier limits the chemical transport (via diffusion and/or convection) of all species but allows migration of ionic species (and hence passage of current) during application of sufficiently large electric fields within electrolyte.

Abstract: This invention relates to modifying a process cell that needs periodic replacement such as the electrolysis cell shown to enable quick connect/disconnect with minimal process downtime. The claimed invention not only modifies the design of the cell but also proposes a housing with a separate compartment for the cell to isolate this from the other components of the system making it easier to replace the cell without the need to disturb the other components.

Abstract: The activity of catalysts used in promoting the oxidation of certain oxidizable species in fluids can be enhanced via electrochemical methods, e.g., NEMCA. In particular, the activity of catalysts used in the selective oxidation of carbon monoxide can be enhanced. A purification system that exploits this effect is useful in purifying reformate supplied as fuel to a solid polymer electrolyte fuel cell stack. The purification system comprises an electrolytic cell with fluid diffusion electrodes. The activity of catalyst incorporated in the cell anode is enhanced.

Abstract: A galvanic cell system (50) in fluid communication with a dewatering system (40) of an inhibited oxidation scrubber (20) removes an oxidation catalyst, i.e., solution phase iron (98), from the process liquor (42) produced by the dewatering system (40) and replaces the iron (98) with magnesium (104) in an oxidation-reduction reaction. An electrolytic cell system (154) in fluid communication with a dewatering system (144) of a forced oxidation scrubber (128) removes an oxidation inhibitor, i.e., solution phase aluminum (174), from the process liquor (146) produced by the dewatering system (144) and replaces the aluminum (174) with iron (170) in an oxidation-reduction reaction. The process liquor (42, 146) is subsequently returned to the scrubber (20, 128) with the solution phase metal (98, 174) selectively removed, thereby enhancing the scrubbing efficiency of the scrubber (20, 128).

Abstract: Electrochemical cell comprises, in one embodiment, a proton exchange membrane (PEM), an anode positioned along one face of the PEM, and a cathode positioned along the other face of the PEM. To enhance electrolysis, platinum catalysts are present between the anode and the PEM and between the cathode and the PEM. A multi-layer metal screen for defining a first fluid cavity is placed in contact with the outer face of the anode, and an electrically-conductive, spring-like, porous pad for defining a second fluid cavity is placed in contact with the outer face of the cathode. The porous pad comprises a mat of carbon fibers having a density of about 0.2-0.55 g/cm3. Cell frames are placed in peripheral contact with the metal screen and the compression pad for peripherally containing fluids present therewithin. Electrically-conductive separators are placed in contact with the metal screen and the compression pad for axially containing fluids present therewithin.

Abstract: The method of producing O2 from water, that includes subjecting water to electrolysis, to produce H2 and O2, returning H2 to a water storage zone, drying the produced O2, using air as a drying agent, flowing a stream of that drying agent air to the cathode side of fuel cell, flowing a stream of produced hydrogen to the anode side of the fuel cell, for reaction with O2 in the agent air to produce water electrical energy and heat, and using electrical energy produced by fuel cell in the electrolysis.

Abstract: A system for producing elemental magnesium (Mg) from seawater having a cell with a pair of permeable membranes which define an anodic compartment with an anode therein and a cathodic compartment with a cathode therein. A space is provided between the pair of membranes through which seawater is allowed to freely flow. A source of electric current is connected to the anode and cathode to charge the compartments in order to cause ions within the seawater to pass from the space into the compartments whereby positive and negative ions are separated. The electric charge associated with the cathode causes the seawater to decompose into H2 and (OH—)2 and positively charged magnesium ions within the seawater pass through the cathodic permeable membrane to combine with the (OH—)2 to form magnesium hydroxide precipitates.

Abstract: An electrochemical cell system includes a hydrogen electrode; an oxygen electrode; a membrane disposed between the hydrogen electrode and the oxygen electrode; and a compartmentalized storage tank. The compartmentalized storage tank has a first fluid storage section and a second fluid storage section separated by a movable divider. The compartmentalized storage tank is in fluid communication with the electrochemical cell. Further, an electrochemical cell includes a hydrogen electrode; an oxygen electrode; an electrolyte membrane disposed between and in intimate contact with the hydrogen electrode and said oxygen electrode; an oxygen flow field disposed adjacent to and in intimate contact with the oxygen electrode; a hydrogen flow field disposed adjacent to and in intimate contact with the hydrogen electrode; a water flow field disposed in fluid communication with the oxygen flow field; and a media divider disposed between the oxygen flow field and the water flow field.

Abstract: The manufacturing apparatus for producing alkaline ionized water and acidic water by electrolysis of water has an electrolytic bath including a cathode cell, an intermediate cell, and an anode cell, separated by diaphragms; an electrolysis solution bath connected to the intermediate cell via an electrolysis solution circulating line and an electrolysis solution circulating pump; a circulation container bath for alkaline ionized water connected to the cathode cell via an alkaline ionized water circulating line and an alkaline ionized water circulating pump; a supplying line for raw material water for producing acidic water connected to an inlet of the anode cell; a withdrawing line for acidic water connected to an outlet of the anode cell; a supplying system for raw material water for making the alkaline ionized water connected to the circulation container bath and a withdrawing line with a water collecting device for withdrawing alkaline ionized water.

Abstract: The present invention provides an ozone generation and delivery system that lends itself to small scale applications and requires very low maintenance. The system preferably includes an anode reservoir and a cathode phase separator each having a hydrophobic membrane to allow phase separation of produced gases from water. The hydrogen gas, ozone gas and water containing ozone may be delivered under pressure.

Abstract: The present invention provides for the electrochemical generation of ozone for use in “point-of-use” applications. The electrochemical ozone generators or systems of the present invention may be used to provide disinfected water, ozone-containing water, and/or ozone gas. Disinfected water may be produced by introducing ozone gas into a potable or purified water source for the purpose of disinfecting or controlling the microorganisms in the water source. Ozonated water or ozone gas may be produced and provided for various anti-microbial and cleansing applications of the consumer, such as washing food, clothing, dishes, countertops, toys, sinks, bathroom surfaces, and the like. Furthermore, the ozone generator may be used to deliver a stream of ozone-containing water for the purpose of commercial or residential point-of-use washing, disinfecting, and sterilizing medical instruments and medical equipment.

Abstract: The invention relates to a gas diffusion electrode (1) comprising a hydrophobic gas diffusion layer (3b), a reaction layer (3a), and a hydrophilic layer (5) arranged in the mentioned order wherein the reaction layer (3a) is arranged to a barrier layer (4), which barrier layer (4), on its opposite side, is arranged to the hydrophilic layer (5). The invention also relates to a method for manufacturing such a gas diffusion electrode (1), and to an electrolytic cell, and use thereof.

Abstract: A device for electrolysis of an aqueous solution of an organic fuel. The electrolyte is a solid-state polymer membrane with anode and cathode catalysts on both surfaces for electro-oxidization and electro-reduction. A low-cost and portable hydrogen generator can be made based on the device with organic fuels such as methanol.

Abstract: An electrochemical cell stack comprising stack walls and a plurality of electrolytic cells within the stack walls, each cell comprising cell members selected from an anode a cathode; a membrane separator frame formed of a non-conductive material and having a frame first planar peripheral surface; a frame second planar peripheral surface; and a central portion defining a membrane-receiving aperture; a membrane within the aperture to provide an anolyte circulation chamber and a catholyte circulation chamber distinct one from the other within the frame, an impermeable cell end wall formed of a non-conductive material between the anode and cathode and the anodes and cathodes of adjacent cells of said stack; wherein each of said anode, said cathode, said separator frame and said end wall has a portion defining an anolyte flow inlet channel, a catholyte flow inlet channel, a spent anolyte channel and a spent catholyte channel; said anolyte flow inlet channel and said spent anolyte channel are in communication with

Abstract: The invention provides a dynamic electrolytic reactor for the reduction of Cr+6 to Cr+3 in aqueous solution. The reactor comprises at least one pair of liquid permeable anode and cathode connectable to an electric current supply. The cathode according to the invention is three-dimensional, and comprises a substrate of flexible porous material whose inner and outer surfaces are coated with an electrically conductive carbon black powder embedded in a binder.