摘要:
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.
摘要:
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.
摘要:
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.-lead dioxide as a mechanical stabilizer for the coating.
摘要:
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.
摘要:
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.
摘要:
Halogen is produced by electrolyzing an aqueous halide in a specially designed cell. The cell comprises an anolyte chamber and a catholyte chamber separated by a permeable membrane or diaphragm, notably an ion exchange (generally cation exchange) polymer. At least one electrode comprises at least two sections. One section comprises a gas and electrolyte permeable layer, sheet or mat having a catalytic surface, i.e. one having a low overvoltage, (low hydrogen overvoltage if the cathode and low halogen overvoltage if the anode). This layer is spaced from the membrane by a second section comprising a thin intermediate electroconductive layer, screen or coating which is in contact with the membrane on one side thereof, the other side thereof being in contact with the main cathode.This second or spacer section advantageously has an electrode surface having a higher overvoltage than the first electrode surface. Preferably the cathode has the above construction.Upon electrolysis of alkali metal chloride or other halide in such a cell and with a cathode of the type described above, a low voltage is obtained even at high current densities and the cathode efficiency is high.The spacer may be in the form of a thin porous coating of metal or the like bonded to or in close contact with the membrane or it may be in the form of a gas and electrolyte permeable screen interposed between the membrane and the lower overvoltage section.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.