An apparatus composed of three canal basins with a lock in between to allow the storage of the solution in each basin. When the lock is lifted slightly it allows the solution to pass into the next basin for use in electrolysis. Carbon electrodes (e.g. mantle peridotite based-activated carbon electrodes or graphite electrodes) that are submerged in the solution (saltwater) are attached to the positive and negative wires of the battery. The battery provides the direct electric current (DC) to power the electrolysis. The carbon electrodes transfer the electrons to the cathode when electricity runs through and passes to the water and carbon electrodes. An electrode connects the cathode wire of the battery and collects some of the electrons and hydrogen ions and transfer them to the cathode tube storage. Afterwards, the hydrogen gas is transferred to the portable hydrogen tank.

An apparatus composed of three canal basins with a lock in between to allow the storage of the solution in each basin. When the lock is lifted slightly it allows the solution to pass into the next basin for use in electrolysis. Carbon electrodes (e.g. mantle peridotite based-activated carbon electrodes or graphite electrodes) that are submerged in the solution (saltwater) are attached to the positive and negative wires of the battery. The battery provides the direct electric current (DC) to power the electrolysis. The carbon electrodes transfer the electrons to the cathode when electricity runs through and passes to the water and carbon electrodes. An electrode connects the cathode wire of the battery and collects some of the electrons and hydrogen ions and transfer them to the cathode tube storage. Afterwards, the hydrogen gas is transferred to the portable hydrogen tank.

A method is described herein that produces UN from UF.sub.6 in at most two steps comprising UF.sub.6.fwdarw.intermediate.fwdarw.UN. The principle of the reaction is that in a first step, UF.sub.6 would be reduced to U.sub.xN.sub.y, where x may be an integer selected from 1 and 3, and y is an integer selected from 1 and 2. Reduction occurs at or near the surface of a gaseous membrane electrode where it is also in contact with a nitrogen bearing salt. In a second step, U.sub.xN.sub.y decomposes to UN and N.sub.2 gas, either in the same reactor as the first step or after removal to a separate unit for further processing.

A method is described herein that produces UN from UF.sub.6 in at most two steps comprising UF.sub.6.fwdarw.intermediate.fwdarw.UN. The principle of the reaction is that in a first step, UF.sub.6 would be reduced to U.sub.xN.sub.y, where x may be an integer selected from 1 and 3, and y is an integer selected from 1 and 2. Reduction occurs at or near the surface of a gaseous membrane electrode where it is also in contact with a nitrogen bearing salt. In a second step, U.sub.xN.sub.y decomposes to UN and N.sub.2 gas, either in the same reactor as the first step or after removal to a separate unit for further processing.

The embodiments of the present disclosure relate to a method, system and composition producing a magnetic carbon nanomaterial product that may comprise carbon nanotubes (CNTs) at least some of which are magnetic CNTs (mCNTs). The method and apparatus employ carbon dioxide (CO.sub.2) as a reactant in an electrolysis reaction in order to make mCNTs. In some embodiments of the present disclosure, a magnetic additive component is included as a reactant in the method and as a portion of one or more components in the system or composition to facilitate a magnetic material addition process, a carbide nucleation process or both during the electrosynthesis reaction for making magnetic carbon nanomaterials.

The embodiments of the present disclosure relate to a method, system and composition producing a magnetic carbon nanomaterial product that may comprise carbon nanotubes (CNTs) at least some of which are magnetic CNTs (mCNTs). The method and apparatus employ carbon dioxide (CO.sub.2) as a reactant in an electrolysis reaction in order to make mCNTs. In some embodiments of the present disclosure, a magnetic additive component is included as a reactant in the method and as a portion of one or more components in the system or composition to facilitate a magnetic material addition process, a carbide nucleation process or both during the electrosynthesis reaction for making magnetic carbon nanomaterials.

Provided is a method of operating an electrolysis apparatus that can inhibit electrode degradation under a variable power supply. The method of operating an electrolysis apparatus includes: an energization step in which electrolysis of electrolyte is performed in an anode compartment including an anode and a cathode compartment including a cathode that are partitioned from each other by a membrane; a suspension step in which electrolysis of electrolyte in the anode compartment and the cathode compartment is suspended; and a discharge step of, in the suspension step, electrically connecting an electrolyzer of the electrolysis apparatus to an external load and adjusting a cell voltage to 0.1 V or less in 5 hours or less.

A method for preparing hydrogen sulfide from sulfur dioxide by electrochemical reduction includes electrochemically reducing sulfur dioxide absorbed in an aqueous solution into gaseous hydrogen sulfide with a membrane electrode, resulting in efficient and selective conversion of the sulfur dioxide absorbed in the aqueous solution into the hydrogen sulfide to avoid a deactivation of a cathode due to colloidal sulfur produced on the cathode and adhesion onto a surface of the cathode, wherein the method is carried out at ambient temperature and normal pressure without addition of a reducing agent, having no waste salts produced, and is simple in operation, and is convenient for large-scale application.

A method for preparing hydrogen sulfide from sulfur dioxide by electrochemical reduction includes electrochemically reducing sulfur dioxide absorbed in an aqueous solution into gaseous hydrogen sulfide with a membrane electrode, resulting in efficient and selective conversion of the sulfur dioxide absorbed in the aqueous solution into the hydrogen sulfide to avoid a deactivation of a cathode due to colloidal sulfur produced on the cathode and adhesion onto a surface of the cathode, wherein the method is carried out at ambient temperature and normal pressure without addition of a reducing agent, having no waste salts produced, and is simple in operation, and is convenient for large-scale application.

The present application provides a method for recovering metal from metal-containing material by leaching, the method comprising providing aqueous solution containing leaching agent precursor, providing one or more source(s) of external energy comprising a source of electric current connected to one or more non-metallic electrode(s) comprising carbon material(s) selected from graphite, graphene and derivatives thereof, and carbon nanomaterial(s) selected from carbon nanofibers, carbon nanotubes and carbon nanobuds, treating the aqueous solution with the external energy, which is electric current providing electrochemical reactions, to form hydrogen peroxide from oxygen in the aqueous solution, reacting the leaching agent precursor with the formed hydrogen peroxide to form a leaching agent and to obtain a leaching solution, providing metal-containing material, reacting the metal-containing material with the leaching solution to obtain soluble metal complexes, and recovering the soluble metal complexes. The present application also discloses a device for recovering metal from metal-containing material by leaching.