Abstract: Described is an osmotic distillation process for concentrating a liquid containing sodium chloride, and in particular a treatment process for used reaction water containing sodium chloride from the production of polymers.

Abstract: The invention relates to an oxygen-consuming electrode, in particular for use in chloralkali electrolysis, comprising a novel catalyst coating based on carbon nanotubes and a silver-based cocatalyst, and to an electrolysis device. The invention further relates to a method for producing said oxygen-consuming electrode and to the use thereof in chloralkali electrolysis or fuel cell technology.

Abstract: The invention relates to an oxygen-consuming electrode, in particular for use in chloralkali electrolysis, comprising a catalyst coating based on carbon nanotubes, and to an electrolysis device. The invention further relates to a method for producing said oxygen-consuming electrode and to the use thereof in chloralkali electrolysis or fuel cell technology.

Abstract: A gas diffusion electrode is described, especially for use in chloralkali electrolysis, said gas diffusion electrode having finely divided components on the liquid side. The electrode is notable for a low perviosity to gases and a lower operating voltage.

Abstract: Electrocatalyst, electrode coating and an electrode for preparing chlorine and process for producing the electrode, the electrocatalyst comprising a noble metal oxide and/or a noble metal of transition groups VIIIa of the Periodic Table of the Elements and at least one finely divided pulverulent oxide of another metal, in which one or more components are doped and the base metal oxide powder is chemically stable in the presence of aqueous electrolytes.

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: A process for wet-chemical production of a catalyst coating on an electrically conductive support for electrodes for chloralkali or hydrochloric acid electrolysis with electro catalytically active components based on noble metal oxides, in which the catalyst coating is produced by; producing a coating solution or dispersion comprising a precursor compound of a noble metal and/or a metal oxide of a noble metal, and a solvent or dispersant, with addition of one or more acids to the coating solution or dispersion, where the molar ratio of the total of the amounts of acid (in mol) present in the coating solution or dispersion to the sum of the amounts of the metals from the metal-containing components present in the coating solution or dispersion is at least 2:1; applying the coating solution or dispersion to the support; substantially freeing the layer applied of solvent or dispersant by drying; and subjecting the dried layer obtained to a thermal treatment to form the catalyst coating.

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: The invention relates to an electrochemical method for producing catalytically active powder from mixtures of metallic silver, optionally with silver oxides, which are particularly suitable for use in oxygen-consuming electrodes, in particular for use in chlor-alkali electrolysis. The invention also relates to the use of said electrodes in chlor-alkali electrolysis or fuel cell technology or in metal/air batteries.

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: Processes for the production of chlorine by multi-stage oxidation, for example, by thermal reaction of hydrogen chloride with oxygen using catalysts or by non-thermal activated reaction of hydrogen chloride with oxygen, in which the gas mixture formed in the reaction, comprising the target products chlorine and water, unreacted hydrogen chloride and oxygen, and possibly other secondary constituents, such as carbon dioxide and nitrogen, (a) is cooled to condense hydrochloric acid as an aqueous solution of hydrogen chloride and (b) the aqueous solution of hydrogen chloride formed is separated from the gas mixture, characterised in that (c) the separated aqueous solution of hydrogen chloride is fed at least partially to an electrochemical oxidation in which at least part of the hydrogen chloride is oxidised to chlorine, (d) the chlorine gas occurring in step d) is optionally added to the gas mixture occurring in step c), (e) the residues of water present in the gas mixture from steps c) and e), in particular by

Abstract: The present invention relates to a method of operating an oxygen-consuming electrode as cathode for the electrolysis of alkali metal chlorides or hydrochloric acid, in an electrochemical cell, comprising feeding an oxygen-containing process gas to the electrode, wherein the oxygen-containing process gas is at least partly heated using a heat source from the electrolysis before contact with the oxygen-consuming electrode to a temperature which corresponds to not more than the temperature of the cathode space in the cell or is less than 50° C. below the temperature of the cathode space in the cell.

Abstract: The invention relates to a method for improving the performance of nickel electrodes in alkali chloride electrolysis by adding water-soluble platinum compounds to the catolyte.

Abstract: Processes for electrolysis of alkali metal chlorides with oxygen-consuming electrodes having startup and shutdown conditions which prevent damage to the constituents of the electrolysis cell.

Abstract: A multilayer oxygen consuming electrode having a side facing the oxygen-containing gas and a side facing the alkaline electrolyte, wherein the electrode includes at least one support, and at least two layers containing a catalyst and a hydrophobic material, wherein the outermost layer facing the gas side has a lower proportion of catalyst than the outermost layer facing the electrode side and wherein the proportion of hydrophobic material is not more than 8% by weight based on the total amount of the catalyst the hydrophobic material.

Abstract: The present invention relates to a process for the continuous preparation of diaryl carbonates from phosgene and at least one monohydroxy compound (monophenol) in the presence of catalysts, and also the use thereof for preparing polycarbonates. The hydrogen chloride formed in the reaction is converted by thermal oxidation into chlorine, with the chlorine being recirculated to the preparation of phosgene. In particular, the process comprises utilization of the hydrogen chloride formed for the process for preparing diphenyl carbonate (DPC process).

Abstract: An oxygen-consuming electrode is described, more particularly for use in chloralkali electrolysis, comprising a novel catalyst coating, as is an electrolysis apparatus. Also described is a production process for the oxygen-consuming electrode and the use thereof in chloralkali electrolysis or fuel cell technology. The oxygen-consuming electrode comprises at least an electrically conductive support, an electrical contact site and a gas diffusion layer comprising a catalytically active component, characterized in that the coating at least one fluorinated polymer, silver in the form of silver particles and silver oxide in the form of silver oxide particles, which is produced in a selected precipitation step.

Abstract: The present invention relates to a process for the continuous preparation of diaryl carbonates from phosgene and at least one monohydroxy compound (monophenol) in the presence of catalysts, and also the use thereof for preparing polycarbonates. The hydrogen chloride formed in the reaction is converted by electrochemical oxidation into chlorine, with the chlorine being recirculated to the preparation of phosgene. In particular, the process comprises utilization of the hydrogen chloride formed for the process for preparing diphenyl carbonate (DPC process).

Abstract: Process for electrolysis of alkali metal chlorides with oxygen-consuming electrodes having specific operating conditions for startup and shutdown, which prevents damage to constituents of the electrolysis cell.

Abstract: An oxygen-consuming electrode is described, more particularly for use in chloralkali electrolysis, comprising a novel catalyst coating based on silver and a finely divided silver oxide, as is an electrolysis apparatus. Also described is a production process for the oxygen-consuming electrode and the use thereof in chloralkali electrolysis or fuel cell technology.