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 present invention provides a method for manufacturing hypochlorite efficiently, using an anode, which has a coating containing palladium oxide by 10 to 45 weight %, ruthenium oxide by 15 to 45 weight %, titanium dioxide by 10 to 40 weight %, and platinum by 10 to 20 weight % as well as an oxide of at least one metal selected from cobalt, lanthanum, cerium or yttrium by 2 to 10 weight % being formed on a conductive base, and a cathode comprising a coating having low hydrogen overvoltage and covered with a reduction preventive film and being formed on a conductive base, and an aqueous solution of a chloride is electrolyzed without a diaphragm.

Abstract: The object of the invention is a method for the electrochemical preparation of metal colloids with particle sizes of less than 30 nm, characterized in that one or more salts of one or more metals of groups Ib, IIb, III, IV, V, VI, VIIb, VIII, lanthanoides, and/or actinoides of the periodic table are cathodically reduced in the presence of a stabilizer, optionally with a supporting electrolyte being added, in organic solvents or in solvent mixtures of organic solvents and/or water within a temperature range of between -78.degree. C. and +120.degree. C. to form metal colloidal solutions or redispersible metal colloid powders, optionally in the presence of inert substrates and/or soluble metal salts of the respective metals. The invention further relates to soluble or redispersible colloids as well as application on substrates and immobilization thereof, in particular for the preparation of catalysts.

Abstract: Electrolyzer comprising at least one elementary cell divided into electrolyte compartments by cation-exchange membranes, said compartments are provided with a circuit for feeding electrolytic solutions and a circuit for withdrawing electrolysis products, said cell is equipped with a cathode and a hydrogen-depolarized anode assembly forming a hydrogen gas chamber fed with a hydrogen-containing gaseous stream, characterized in that said assembly comprises a cation-exchange membrane, a porous, flexible electrocatalytic sheet, a porous rigid current collector having a multiplicity of contact points with said electrocatalytic sheet, said membrane, sheet and current collector are held in contact together by means of pressure without bonding.

Abstract: An electrochemical process for producing unsaturated hydrocarbon compounds from unsaturated hydrocarbon compounds and for extracting oxygen from a gas containing N.sub.2 O, NO, NO.sub.2, SO.sub.2, or SO.sub.3 is described. The process is characterized by the use of mixed metal oxide materials having a perovskite structure represented by the formula:A.sub.s A'.sub.t B.sub.u B'.sub.v B".sub.w O.sub.xwherein A represents a lanthanide or Y, or a mixture thereof; A' represents an alkaline earth metal or a mixture thereof; B represents Fe; B' represents Cr or Ti, or a mixture thereof; and B" represents Mn, Co, Vi, Ni or Cu, or a mixture thereof.

Abstract: The invention relates to a process for treating a low-concentrated aqueous feed solution which includes at least one aqueous process stream from a pulp mill. The process includes concentrating the feed solution by evaporation to form an evaporation concentrate, and subjecting at least a part of the concentrate to a first electrodialysis treatment, thereby forming a first electrodialysis concentrate containing salt removed from the evaporation concentrate and at least one diluate depleted in the salt. The invention also relates to a plant for carrying out the above process.

Abstract: The method for producing electrolyzed water includes the step of applying a voltage to electrodes disposed in an electrolytic cell containing therein pure water including electrolyte therein. A strength of an electric field generated by applying a voltage to the electrodes is controlled to be variable by means of various techniques. The method makes it possible to produce electrolyzed water with a smaller amount of energy than prior methods.

Abstract: A water electrolyzer for electrolyzing water to produce and recover acidic and/or alkaline water. The electrolyzer is of the membraneless laminar-flow type which is designed to electrolyze water without placing a membrane between the electrodes. To this end, the anode and cathode are arranged closely with one another with a very small spacing (generally less than 1 mm) to establish a laminar flow in a narrow flow path. The anode is provided with a slit-shaped aperture for separating a thin layer of acidic water flowing along the anode surface. This aperture is situated sufficiently upstream of the downstream end of the flow path to ensure that the layer of acidic water is separated away from the remainder of the laminar flow while the laminar flow is sustained in the flow path. Accordingly, formation of turbulence at a point of acidic water separation is minimized so that highly acidic water can be recovered.

Abstract: Improved electrochemical processes for producing high purity grades of hydrogen iodide without developing cell fouling iodine solids through oxidation of iodide at the anode back migrating through ion exchange membrane into anolyte compartment. Two and three compartment electrochemical cells have anolyte solutions with chemical agents for oxidizing back migrating iodides to soluble iodine species to avoid build up of iodine solids on key cell components. Other embodiments include processes with undivided electrochemical cells fitted with hydrogen depolarized anodes, optionally operating electrogeneratively producing at least some of its own power requirements while simultaneously producing HI, or processes of making high purity HI with multi-phase aqueous/non-aqueous anolytes for solubilizing iodine solids as they develop in the anolyte compartment.

Abstract: An electrochemical cell/electrolyte/mediator combination for the efficient destruction of organic contaminants using metal salt mediators in a sulfuric acid electrolyte, wherein the electrodes and mediator are chosen such that hydrogen gas is produced at the cathode and no cell membrane is required.