Abstract: This disclosure is directed to a membrane or diaphragm-free, electrolytic process for removal of a significant portion of at least one metal contaminant from waste water containing it comprising contacting said waste water with a plurality of anodes, each anode having openings to permit the flow of waste water therethrough, and a plurality of metallized organic polymer foam reticulate cathodes wherein said anodes and reticulate cathodes are arranged in alternating manner and electrically energized.

Abstract: This invention is directed to a membrane or diaphragm-free electrolytic cell device for removal of a metal(s) present as a contaminant(s) in waste water comprising a nonconductive cell box having an upper peripheral flange, anode and cathode bus bars located on said cell box below said flange, inlet and outlet means to pass the liquid through the electrodes contained in said box, means to space the anodes and cathodes contained within said cell box, a plurality of anodes having openings to permit the flow of waste water therethrough, a plurality of reticulate cathodes, and means connecting the anodes and cathodes, respectively, to said bus bars and to a source of electrical energy whereby the metal contaminant(s) present in such water are deposited on the reticulate cathodes predominantly.

Abstract: An active metal coating which lowers the hydrogen discharge overpotential at the cathode in the electrolysis of aqueous alkali metal halide solutions is deposited on the cathode tubes of a cathode can of an electrolysis cell without the removal of the tubes from the can. Plating solution and anodes of plating metal are placed inside a cathode can and the components are electrically connected so as to deposit an active coating onto the cathode tubes. The plating metal is preferably an alloy of nickel and zinc and the process involves the final step of leaching the zinc component of the alloy deposit from the plated cathode tubes to provide a porous, active nickel surface which results in a reduction of the hydrogen discharge overpotential for the electrolysis of alkali metal halides, particularly sodium chloride.

Abstract: Electrolysis of impure solutions containing hardness impurities such as calcium and magnesium causes deposits to form on the cathodes of such an electrolysis cell which rapidly reduces the efficiency of the cell. The electrolysis cell of the instant invention contains a plurality of cathodes. The efficiency of such a cell is rejuvenated periodically by changing the polarity of less than the total number of cathodes in said cell so as to clean such cathodes while continuing normal operation of the cell by means of the remaining cathodes.

Abstract: A cathode adapted for the electrolysis of water or an aqueous solution of an alkali metal halide salt because it gives prolonged lowering of hydrogen overvoltage is provided by an electrically conductive substrate bearing on its surface a coating produced by melt spraying an admixture of particulate nickel or cobalt and particulate aluminum and then leaching out the aluminum.

Abstract: A cathode adapted for the electrolysis of water or an aqueous alkali metal halide salt solutions because it gives prolonged lowering of hydrogen overvoltage is provided by an electrically conductive substrate bearing on its surface a coating of a melt-sprayed admixture of particulate cobalt and particulate zirconia.