Abstract: Electrolyzer comprising at least one single electrolyzer element which comprises at least one anode compartment with an anode, one cathode compartment with a cathode and one ion exchange membrane arranged between the anode and the cathode compartments, with the anode and/or cathode being a gas diffusion electrode. A gap is provided between the gas diffusion electrode and the ion exchange membrane, with an electrolyte inlet arranged at the upper end of the gap and an electrolyte outlet at the lower end of the gap and a gas inlet and a gas outlet. The electrolyte outlet extending into a discharge header, and the electrolyte inlet connected to an electrolyte feed tank and having an overflow, the overflow connected to the discharge header, with a coiled hose connecting the electrolyte feed tank with the electrolyte inlet and with a coiled hose connecting the overflow with the discharge header.

Abstract: The invention relates to an electrolysis cell of the single-element type design for chlor-alkali electrolysis plants, comprising an anode compartment and a cathode compartment, each of the two compartments containing an electrode connected to the rear wall of the respective compartment by means of parallel bars. The electrodes are thus subdivided into several sections. In accordance with the invention, at least one of two electrodes is provided with a curved shape in each section, this curved section protruding towards the opposite electrode and pressing a membrane area against the opposite electrode. According to a preferred embodiment, the curved shape of the various electrode sections is obtained by means of springs.

Abstract: The invention relates to an electrochemical cell comprising an anode and a cathode compartment separated by a membrane, housing corresponding electrodes. The anode and the cathode compartments having external walls with frame-type flanged areas in the contact area of both compartments. The flanged areas having mounting bores marking an inner area and an outer area of the electrochemical cell a, gas-diffusion electrode resting on a support system, a porous material resting on the gas-diffusion electrode, and devices for the inlet and outlet of gas and electrolyte. At least one circumferential gasket frame is in the contact area of both compartments, between the frame-type flanged areas of the external walls of both compartments, said gasket resting on the membrane, with the porous material and the gas-diffusion electrode resting on the frame-type cathodic flanged area and the circumferential gasket frame overlapping in this area with the porous material and the gas-diffusion electrode.

Abstract: The invention relates to an electrochemical cell comprising an anode and a cathode compartments, separated by a membrane, having corresponding electrodes; said anode and cathode compartments each having an external wall, flanged areas designed like frames in the contact area of the compartments, and a gas diffusion electrode comprising a liquid-permeable carrier coated with a catalyst material; said gas diffusion electrode featuring an area not coated with catalyst at its bottom edge, said area, at the bottom end of the electrochemical cell, protruding between the flanged areas of the external wall of the cathode compartment and the flanged areas of the external wall of the anode compartment in the contact area of the compartments; a porous material arranged parallel between the gas diffusion electrode and the membrane, and devices for the supply and discharge of gas and electrolyte, with a gas space separated from an electrolyte space by appropriate means.

Abstract: Method for the gastight and liquid-tight installation of oxygen-consuming electrodes in an electrolysis apparatus, and electrolysis apparatus for use in chloralkali electrolysis, in which particular regions are covered with an additional film having a composition comparable to the oxygen-consuming electrodes

Abstract: Electrolyser comprising at least one single electrolyser element which comprises at least one anode compartment with an anode, one cathode compartment with a cathode and one ion exchange membrane arranged between the anode and the cathode compartments, with the anode and/or cathode being a gas diffusion electrode. A gap is provided between the gas diffusion electrode and the ion exchange membrane, with an electrolyte inlet arranged at the upper end of the gap and an electrolyte outlet at the lower end of the gap and a gas inlet and a gas outlet. The electrolyte outlet extending into a discharge header, and the electrolyte inlet connected to an electrolyte feed tank and having an overflow, the overflow connected to the discharge header, with a coiled hose connecting the electrolyte feed tank with the electrolyte inlet and with a coiled hose connecting the overflow with the discharge header.

Abstract: A method for coating a substrate on one or more sides having catalytically active material producible by material deposition under vacuum in a vacuum chamber, using the following steps: loading a substrate in the chamber evacuating the chamber, cleaning the substrate by introducing a gaseous reducing agent, removing the gaseous reducing agent, applying an intermediate layer by means of vacuum arc evaporation, wherein a substrate comprising the same or similar material is introduced into the vacuum chamber, controlling the chamber temperature, coating by vacuum arc evaporation, a metal taken from the group ruthenium, iridium, titanium and mixtures thereof while oxygen is supplied, in a last step the coated substrate is removed from the chamber, wherein at least 99% of the substrate coating is free of constituents originally contained in the substrate itself, and at least 99% of the coating applied on the intermediate layer is kept free of non-oxidized metals.

Abstract: The invention relates to an electrolysis device for cleaning acidic waters which comprises a cathode, an anode, and an ion exchange membrane, wherein the membrane is arranged between the cathode and the anode and is attached at least along the entire circumference of its rim, wherein many inlets and outlets are arranged along the upper and lower rim of the electrolysis device which are linked to the cathode space or to the anode space, in such a way that a plug flow, ideally with a laminar profile, is created in the cathode space and in the anode space.

Abstract: The invention relates to a method for producing electrically conducting nickel oxide surfaces made of nickel-containing material. According to the method, the nickel surface is first degreased and is then roughened for approximately ten minutes in a solution containing about one percent of hydrochloric acid, the process being accelerated by adding hydrogen peroxide solution, resulting in the electrolyte turning green. The nickel surface is briefly wetted, the nickel material is introduced into a solution of 3.5 molar lye to which about ten percent of hydrogen peroxide is added and is kept therein for ten minutes, and the resulting nickel hydroxide surface is dehydrated in a subsequent thermal process and is then further oxidized to obtain nickel oxide. The invention further relates to a conductive boundary layer that is produced according to the method, the electrodes therefrom, and the use thereof in chlorine-alkali electrolysis processes, in fuel cells and storage batteries.

Abstract: Electrolysis cell in the constructive form of single elements, intended for instance for the production of chlorine, hydrogen and/or caustic soda and designed in such a way that the portion of inactive membrane surface is minimised thanks to an optimised flange type so that the ratio between the flange surface of a semi-shell and the active membrane surface can be set to less than 0.045, neither the semi-shells nor the membrane being provided with bores or recesses for accommodating the clamping members.

Abstract: The invention relates to an insulating frame of an electrolysis cell having a microstructured internal section allowing the penetration of the electrolyte even if the structured section is partly or completely overlapped by the membrane, and to an electrolysis cell equipped with the same.

Abstract: The invention relates to an electrolytic cell for the production of chlorine from an aqueous alkali halide solution, which mainly consists of two semi-shells, an anode, a cathode and an ion exchange membrane arranged between the electrodes. Spacer elements are arranged between the ion-exchange membrane and the electrodes for fixing the membrane in position and distributing the compressive forces, made of electrically conductive and corrosion-resistant material on at least one side of the membrane.

Abstract: The invention relates to an electrolysis device for cleaning acidic waters which comprises a cathode, an anode, and an ion exchange membrane, wherein the membrane is arranged between the cathode and the anode and is attached at least along the entire circumference of its rim, wherein many inlets and outlets are arranged along the upper and lower rim of the electrolysis device which are linked to the cathode space or to the anode space, in such a way that a plug flow, ideally with a laminar profile, is created in the cathode space and in the anode space.

Abstract: A device for the linear butt welding of thin metal sheets without weld filler materials comprising movable welding heads, a clamping device having at least two pressing elements which operate independently of one another at least one of the pressing elements being suitable for applying two or more distinct pressure levels and additional horizontal pressing elements are further provided in order to press the metal sheets to be welded against one other while being deformed, until full-area contact of the metal-sheet edges butting against one another is achieved as well as a welding method making use of the device.

Abstract: An electrode for electrochemical processes for gas production, which in the installed state is located parallel and opposite to an ion exchange membrane and consists of a multitude of horizontal lamellar elements which are structured and three-dimensionally shaped and are in contact with only one surface with the membrane, wherein the lamellar elements have grooves and holes, the major part of the holes being placed in the grooves and the surfaces of such holes or part thereof are located in the grooves or extend into the grooves whereby the holes are ideally placed in the contact area of the respective lamellar element with the membrane.

Abstract: An electrolytic cell consisting of two semi-shells and encompassing mainly the inlet and outlet devices, components for the flow control, a membrane as well as anode and cathode.

Abstract: The invention relates to a method for coating one or more sides of substrates with catalytically active material, comprising material deposition under vacuum in a vacuum chamber, wherein the following steps are performed: (a) loading the vacuum chamber with at least one substrate, (b) closing and evacuating the vacuum chamber, (c) cleaning the substrate by introducing a gaseous reducing agent into the vacuum chamber, (d) increasing the size of the substrate surface by depositing a vaporous component on the substrate surface, (e) coating by a coating process taken from the group of plasma coating processes, physical gas deposition, sputtering processes or the like, wherein one or more metals and/or alkaline and/or earth alkaline metals or their oxides are applied to the surface of the substrate. This method may be used, for example, for coating electrodes which are used in the chlor-alkali electrolysis.

Abstract: In the case of a process for the manufacture of contact strips, in particular for electrolysers (membrane cells), the objective is to provide a solution that allows to create a cheap but also extremely efficient method for the manufacture of such contact strips at a high electrical efficiency. This objective is achieved by applying the roll bonding method to attach a copper strip to a titanium strip.

Abstract: The invention relates to an electrolysis cell of the single-element type design for chlor-alkali electrolysis plants, comprising an anode compartment and a cathode compartment, each of the two compartments containing an electrode connected to the rear wall of the respective compartment by means of parallel bars. The electrodes are thus subdivided into several sections. In accordance with the invention, at least one of two electrodes is provided with a curved shape in each section, this curved section protruding towards the opposite electrode and pressing a membrane area against the opposite electrode. According to a preferred embodiment, the curved shape of the various electrode sections is obtained by means of springs.

Abstract: The invention relates to an insulating frame of an electrolysis cell having a microstructured internal section allowing the penetration of the electrolyte even if the structured section is partly or completely overlapped by the membrane, and to an electrolysis cell equipped with the same.