A system for controlling an electrochemical production process includes a variable controllable power circuit and an electrolytic cell. The cell includes two electrodes and operates in different states dependent on the potential difference across the electrodes. The system includes a power circuit controller that causes the power circuit to apply a given potential difference across the electrodes to initiate operation of the cell in the one of multiple possible states associated with the given potential difference. The possible states include a production state associated with a first non-zero potential difference in which a product of interest is produced, and an idle state associated with a second non-zero potential difference in which the product of interest is not produced. A monitoring and control subsystem maintains a predefined set of production process conditions, including a predefined operating temperature range, while the cell operates in both the production state and the idle state.

The present invention provides a molten-salt electrolytic refining apparatus for refining a raw-material alloy containing indium using a molten-salt electrolytic refining method. The molten-salt electrolytic refining apparatus includes a reaction crucible provided in a reaction container so as to be filled with a molten-salt electrolytic solution, an anode and a cathode immersed in the molten-salt electrolytic solution, an anode crucible in which a liquid raw-material alloy is contained, a cathode crucible in which at least one raw-material metal included in the raw-material alloy is recovered in a liquid phase, and a heater provided so that the temperature of the molten-salt electrolytic solution is adjusted to be equal to or greater than the melting temperature of the raw-material alloy. The present invention also provides a molten-salt electrolytic refining method which includes recovering indium (In) from an indium-tin (In—Sn) alloy using a molten-salt electrolytic solution containing fluoride.

The present invention provides a molten-salt electrolytic refining apparatus for refining a raw-material alloy containing indium using a molten-salt electrolytic refining method. The molten-salt electrolytic refining apparatus includes a reaction crucible provided in a reaction container so as to be filled with a molten-salt electrolytic solution, an anode and a cathode immersed in the molten-salt electrolytic solution, an anode crucible in which a liquid raw-material alloy is contained, a cathode crucible in which at least one raw-material metal included in the raw-material alloy is recovered in a liquid phase, and a heater provided so that the temperature of the molten-salt electrolytic solution is adjusted to be equal to or greater than the melting temperature of the raw-material alloy. The present invention also provides a molten-salt electrolytic refining method which includes recovering indium (In) from an indium-tin (In—Sn) alloy using a molten-salt electrolytic solution containing fluoride.

A method for cleanly extracting metallic silver includes: mixing an acidic solution containing Ce.sup.4+ and NO.sub.3.sup.− with a silver-containing material for leaching; after the leaching is completed, carrying out a solid-liquid separation to obtain a leaching solution containing Ce.sup.3+ and Ag.sup.+; and electrolyzing the leaching solution, wherein an oxidation reaction of Ce′ occurs at an anode to realize a regeneration of Ce.sup.4+ and an electrolytic reduction occurs at a cathode to reduce Ag.sup.+ to obtain the metallic silver. Ce.sup.4+ is used as a leaching agent and an intermediate oxidant to implement a cyclic operation of solution leaching and electrolytic regeneration on the silver-containing material. Almost no NO.sub.x and waste liquid are caused by the extraction process, and the invention is clean and environmentally friendly.

In one embodiment, the disclosed subject matter relates to an electrolytic cell that has: a cell reservoir; a cathode support retained on a bottom of the cell reservoir, wherein the cathode support contacts at least one of: a metal pad and a molten electrolyte bath within the cell reservoir, wherein the cathode support includes: a body having a support bottom, which is configured to be in communication with the bottom of the electrolysis cell; and a support top, opposite the support bottom, having a cathode attachment area configured to retain a at least one cathode plate therein.

The invention related to a method for extracting tin and/or lead contained in an electrically conductive mixture derived from waste, using a solution comprising methane sulphonic acid as an electrolytic solution.

An electrolytic cell for the production of aluminium including collector bars under the cathode, namely a copper collector bar whose external terminal end is connected by a conductor element providing electrical connection of the collector bar to an external bus. This conductor element comprises a flexible connector strip of the same or a different highly conductive metal as the conductor bar, such as copper.

A system to remove sodium and Sulfur from a feed stream containing alkali metal sulfides and polysulfides in addition to heavy metals. The system includes an electrolytic cell having an anolyte compartment housing an anode in contact with an anolyte. The anolyte includes alkali metal sulfides and polysulfides dissolved in a polar organic solvent. The anolyte includes heavy metal ions. A separator includes an ion conducting membrane and separates the anolyte compartment from a catholyte compartment that includes a cathode in contact with a catholyte. The catholyte includes an alkali ion-conductive liquid. A power source applies a voltage to the electrolytic cell high enough to reduce the alkali metal and oxidize Sulfur ions to allow recovery of the alkali metal and elemental sulfur. The ratio of sodium to Sulfur is such that the open circuit potential of the electrolytic cell is greater than about 2.3V.

A system to remove sodium and Sulfur from a feed stream containing alkali metal sulfides and polysulfides in addition to heavy metals. The system includes an electrolytic cell having an anolyte compartment housing an anode in contact with an anolyte. The anolyte includes alkali metal sulfides and polysulfides dissolved in a polar organic solvent. The anolyte includes heavy metal ions. A separator includes an ion conducting membrane and separates the anolyte compartment from a catholyte compartment that includes a cathode in contact with a catholyte. The catholyte includes an alkali ion-conductive liquid. A power source applies a voltage to the electrolytic cell high enough to reduce the alkali metal and oxidize Sulfur ions to allow recovery of the alkali metal and elemental sulfur. The ratio of sodium to Sulfur is such that the open circuit potential of the electrolytic cell is greater than about 2.3V.

Techniques described herein relate to an article, including an electrolytic tank for refining metals, and related production techniques, wherein the article defines a channel or cavity receiving a corrosive medium including sulfuric acid. The article includes a corrosion-resistant lead coating including at least one layer of lead solidified onto at least a portion of the cavity. The corrosion-resistant coating can be combined with additional layers including fiberglass-based material for further protection against corrosion.