Abstract: An improved process for the production of halogens and alkali metal hydroxide by electrolysis of aqueous solution of alkali metal halides in a flowing mercury electrolysis cell wherein the salt solutions do not have to purified and to novel amalgam denuders and a mercury electrolytic cell plant without a salt purification step.

Abstract: Describes a monopolar diaphragm electrolytic cell with dimensionally stable anodes in which the anodes rest freely in the cell and are spring-pressed toward the diaphragms by spring-loaded transverse arms on the positive current carriers, which in use contact, but are not mechanically connected to, the anodes, the spring-pressed electrical contacts between the transverse arms and the anodes are sufficient to carry current to the anodes without substantial ohmic drop through these contacts and permit the anodes to be removed from the cells for recoating and other purposes without destroying any welds or other permanent mechanical connections between the anodes and other portions of the cell.

Abstract: A novel polyphase packing for alkali metal mercury amalgam denuders comprised of a sintered mixture of powdered valve metal borides and valve metal carbides, a novel amalgam denuder containing the said polyphase packing and a novel process of decomposing alkali metal mercury amalgam by contacting the amalgam with an aqueous media in the presence of the said polyphase packing.

Abstract: Describes an electrolysis cell having metal anodes (preferably titanium) and metal cathodes connected together back to back by a metal to metal contact forming a bimetallic partition. The anodes and cathodes are in wave form with their active surfaces intermeshed together and the cell may be unipolar or bipolar with terminal positive and negative end unit cells and a plurality of intermediate cell units.

Abstract: Relates to anodes for electrolytic cells, for the electrolysis of brine solutions, having primary lead-in means of high conducting capacity (copper) for supplying anodic current to the cell from outside the cell and connected to a current supply source, primary conducting means of lower conducting capacity (titanium, or tantalum or alloys thereof) inside the cell, secondary conducting means of lower conducting capacity (titanium, or tantalum or alloys thereof) inside the cell for conducting current to an electrocatalytically active coating carried on a valve metal base, said electrocatalytic coating being capable of catalyzing halogen ion discharge without becoming passivated over long periods of time, said anodes serving to distribute the current in a cascade fashion from the primary lead-ins to the anode face.

Abstract: An alkali chlorine diaphragm cell such as is constructed in a conventional manner whereby evolved gaseous chlorine rises in the pool of alkali metal chloride solution is provided with recycling means to recycle the solution from an upper level of the solution to a predetermined lower level of the solution adjacent the cell bottom, a plurality of spaced conduits are preferably provided for this purpose.The downward recirculation of the electrolyte through these conduits is induced by the upward movement of the electrolyte caused by the gaseous chlorine rising in the electrolyte outside the conduits. These conduits advantageously are located at or near anode surfaces and prevent or restrain lateral movement of recycled electrolyte until the recycled electrolyte reaches such lower level usually adjacent the bottom of the anolyte chamber.

Abstract: Describes an electrochemical process operated at relatively low cathodic current density and high anodic current density, particularly for electrowinning and electrorefining processes using dimensionally stable metal anodes with reduced anodic electrocatalytic surfaces to allow full exploitation of the advantages of insoluble metal anodes, such as lower overvoltages, high current density capability, and purer deposits, together with an economical employment of expensive anode materials. Cathodic/anodic current densityratios down to 1/20 are used without materially decreasing overall process efficiency or product's morphology. Choice of geometric parameters, practical aspects, typical embodiments and examples are disclosed.

Abstract: Describes an electrolysis cell and method of operation in which metal anodes (preferably titanium) provided with an electrically conducting electrocatalytic coating, in an anode compartment, face metal cathodes (preferably diaphragm covered) in a cathode compartment, in which the anodes are spaced from an imperforate valve metal separating partition by a separating wall behind which the anolyte can recirculate downward. The anodic gases rising in the anode compartment discharge into a brine box above the anode compartment near the center thereof and the anolyte recirculates downward near at least one end of the anode compartment, and a method of operation which provides circulation from front to back of the anode compartment and from center to the sides of the anode compartment.

Abstract: Provides an imperforate valve metal blanket between the cell base of a electrolysis cell and the cell can, which acts as a conductor from the positive current leads to dimensionally stable anodes and provides hollow anodes with perforate and imperforate sections to promote anolyte circulation within the cell.

Abstract: Novel vertical multiunit electrolyzers with bipolar metallic electrodes for the electrolysis of halide containing electrolytes to produce oxidized halogen compounds and to a novel electrolysis of electrolytes which is designed to produce a gas lift effect to sweep solid deposits off the electrodes and out of the electrolyzer.

Abstract: Describes an electrolysis cell and method of operation in which metal anodes (preferably titanium) provided with an electrically conducting electrocatalytic coating, in an anode compartment, face metal cathodes (preferably diaphragm covered) in a cathode compartment, in which the anodes are spaced from an imperforate valve metal separating partition by a separating wall behind which the anolyte can recirculate downward. The anodic gases rising in the anode compartment discharge into a brine box above the anode compartment near the center thereof and the anolyte recirculates downward near at least one end of the anode compartment, and a method of operation which provides circulation from front to back of the anode compartment and from center to the sides of the anode compartment.

Abstract: Novel electrodes consisting essentially of a valve metal base or other electrically conductive material which is corrosion-resistant to the anodic conditions having on at least a portion of its outer surface an electrocatalytic coating of .beta.-manganese dioxide chemi-deposited by thermal decomposition of an alcoholic solution of manganese nitrate which are useful in electrolysis processes in which oxygen is formed at the anode such as electrowinning of metals from sulfuric acid solution or in the electrolytic production of perchlorates. Also included are electrodes where the .beta.-manganese dioxide coating is activated by doping with up to 5% by weight of at least one metal of the groups IB, IIB, IVA, VA, VB, VIB, VIIB, and VIII of the Periodic Table excluding the platinum group metals, gold and silver or activated by irradiation of the .beta.-manganese dioxide coating and/or stabilized by the addition of up to 20% by weight of silicon dioxide, tin dioxide or .beta.

Abstract: Provides an imperforate valve metal blanket between the cell base of a diaphragm electrolysis cell and the cell can, which acts as a conductor from the positive current leads to dimensionally stable anodes and provides hollow anodes with perforate and imperforate sections to promote anolyte circulation within the cell.

Abstract: Describes an electrolysis cell having metal anodes (preferably titanium) and metal cathodes connected together by a metal-to-metal contact. The anodes and cathodes are in wave form, intermeshed together, and the cell may be unipolar or bipolar with terminal positive and negative end unit cells and a plurality of intermediate cell units. The method of electrolyte feeding and recirculation is applicable to the electrolysis cell specifically described and to other electrolysis cells having vertically arranged anodes and cathodes.

Abstract: A novel process for the preparation of an alkali metal halate by electrolysis of an aqueous alkali metal halide solution comprising passing an alkali metal halide solution upwardly through a plurality of bipolar electrolysis units while passing an electrolysis current therethrough at a temperature of 90.degree. to 110.degree. C and at a current density to volume ratio of 15 to 30 A/liter to convert at least a portion of the alkali metal halide to alkali metal hypohalite, passing the resulting electrolyte while venting the hydrogen formed to a reaction zone whose volume is sufficient to provide a residence time to substantially complete the conversion of the alkali metal hypohalite to alkali metal halate and recovering the said halate from the electrolyte and an apparatus for performing the said process.

Abstract: Novel vertical multiunit electrolyzers with bipolar metallic electrodes for the electrolysis of halide containing electrolytes to produce oxidized halogen compounds and to a novel electrolysis of electrolytes which is designed to produce a gas lift effect to sweep solid deposits off the electrodes and out of the electrolyzer.

Abstract: Describes a bipolar diaphragm cell consisting of a series of substantially horizontal frames stacked one on top of the other with the interposition of insulating gaskets. These frames house the cathode compartment in the upper part and the anode compartment in the lower part of each frame; these compartments are separated by a horizontal plate supporting the cathode screen and diaphragm on its upper side and the anodic structure from its lower side; the anodic structure consisting of a valve metal base having an electrically conductive electrocatalytic coating thereon and having sufficient voids through the metal of the anode base to readily pass anode gases upwardly through the anodes.

Abstract: Provides an imperforate valve metal blanket between the cell base of a diaphragm electrolysis cell and the cell can, which acts as a conductor from the positive current leads to dimensionally stable anodes and provides hollow anodes with perforate and imperforate sections to promote anolyte circulation within the cell.

Abstract: Describes an electrolysis cell having metal anodes (preferably titanium) and metal cathodes connected together, back to back, by a metal to metal contact forming a bimetallic partition. The anodes and cathodes are in wave form with their active surfaces intermeshed together and the cell may be unipolar or bipolar with terminal positive and negative end unit cells and a plurality of intermediate cell units.

Abstract: Describes electrolysis diaphragm cells with substantially vertical, dimensionally stable, valve metal anodes and steel cathodes forming substantially vertical interelectrodic gaps therebetween with grooved, slotted, reticulated or rod type anodes and baffles on either the front or back, or on both the front and back, of said anodes to direct the anodic gases away from the interelectrodic gap, and slots or other openings in the anodes, adjacent said baffles, through which the anodic gases pass to the rear of the anodes, to thereby protect the diaphragms against destruction by the anodic gases produced in the interelectrodic gap.