A method of producing iron metal by electrolysis of iron ore can include introducing iron ore into an anode chamber. The anode chamber can include a first electrolyte and an anode. The anode can oxidize water to form O.sub.2 gas and H.sup.+ ions in the anode chamber. The iron ore can be dissolved to form Fe.sup.3+ and/or Fe.sup.2+ ions in the anode chamber. The Fe.sup.3+ and/or Fe.sup.2+ ions can be transferred from the anode chamber to a cathode chamber through a cation exchange membrane that separates the anode chamber from the cathode chamber. The cathode chamber can include a second electrolyte and a cathode. The Fe.sup.3+ and/or Fe.sup.2+ ions can be reduced to form iron metal at the cathode.

Methods and systems for dissolving an iron-containing ore are disclosed. For example, a method of processing and dissolving an iron-containing ore comprises: thermally reducing one or more non-magnetite iron oxide materials in the iron-containing ore to form magnetite in the presence of a reductant, thereby forming thermally-reduced ore; and dissolving at least a portion of the thermally-reduced ore using an acid to form an acidic iron-salt solution; wherein the acidic iron-salt solution comprises protons electrochemically generated in an electrochemical cell.

Methods and systems for dissolving an iron-containing ore are disclosed. For example, a method of processing and dissolving an iron-containing ore comprises: thermally reducing one or more non-magnetite iron oxide materials in the iron-containing ore to form magnetite in the presence of a reductant, thereby forming thermally-reduced ore; and dissolving at least a portion of the thermally-reduced ore using an acid to form an acidic iron-salt solution; wherein the acidic iron-salt solution comprises protons electrochemically generated in an electrochemical cell.

Methods and systems for producing are disclosed. A method for producing iron, for example, comprises: providing an iron-containing ore to a dissolution subsystem comprising a first electrochemical cell; wherein the first anolyte has a different composition than the first catholyte; dissolving at least a portion of the iron-containing ore using an acid to form an acidic iron-salt solution having dissolved first Fe.sup.3+ ions; providing at least a portion of the acidic iron-salt solution to the first cathodic chamber; first electrochemically reducing said first Fe.sup.3+ ions in the first catholyte to form Fe.sup.2+ ions; transferring the formed Fe.sup.2+ ions from the dissolution subsystem to an iron-plating subsystem having a second electrochemical cell; second electrochemically reducing a first portion of the transferred formed Fe.sup.2+ ions to Fe metal at a second cathode of the second electrochemical cell; and removing the Fe metal.

Methods and systems for producing are disclosed. A method for producing iron, for example, comprises: providing an iron-containing ore to a dissolution subsystem comprising a first electrochemical cell; wherein the first anolyte has a different composition than the first catholyte; dissolving at least a portion of the iron-containing ore using an acid to form an acidic iron-salt solution having dissolved first Fe.sup.3+ ions; providing at least a portion of the acidic iron-salt solution to the first cathodic chamber; first electrochemically reducing said first Fe.sup.3+ ions in the first catholyte to form Fe.sup.2+ ions; transferring the formed Fe.sup.2+ ions from the dissolution subsystem to an iron-plating subsystem having a second electrochemical cell; second electrochemically reducing a first portion of the transferred formed Fe.sup.2+ ions to Fe metal at a second cathode of the second electrochemical cell; and removing the Fe metal.

The present disclosure relates to a method for removing halide from halide-containing Waelz oxide. According to the method, it is possible to effectively remove halide contained in Waelz oxide, especially insoluble fluoride such as CaF.sub.2, which are difficult to remove under atmospheric pressure conditions and present as insoluble substances. Accordingly, in the process of recovering valuable metals, an additional process for adjusting the concentration of fluorine or chlorine present in the electrolyte can be omitted, and costs can be reduced.

The present disclosure relates to a method for removing halide from halide-containing Waelz oxide. According to the method, it is possible to effectively remove halide contained in Waelz oxide, especially insoluble fluoride such as CaF.sub.2, which are difficult to remove under atmospheric pressure conditions and present as insoluble substances. Accordingly, in the process of recovering valuable metals, an additional process for adjusting the concentration of fluorine or chlorine present in the electrolyte can be omitted, and costs can be reduced.

Provided is a method for efficiently separating and recovering tungsten and other valuable(s) from at least one valuable containing tungsten. The present invention relates to a method for recovering at least one valuable containing tungsten, comprising subjecting a raw material mixture comprising at least one valuable containing tungsten to electrolysis using an electrolytic solution containing at least one alcohol amine to dissolve tungsten in the electrolytic solution, electrodeposit a part of the valuable(s) onto a cathode used for the electrolysis and separate at least one valuable other than the valuable(s) electrodeposited onto the cathode as a residue in the electrolytic solution, and then separating and recovering each of the residue and the valuable(s) electrodeposited onto the cathode.

A method in which an anode chamber and a cathode chamber are separated by a cation exchange membrane, an acid solution containing metal ions is introduced into the anode chamber, a cathode solution is introduced into the cathode chamber, and a current is applied across the anode and the cathode, whereby the metal ions in the solution in the anode chamber pass through the cation exchange membrane, move into the cathode solution, and precipitate as metal onto the cathode, wherein there are minimal instances where electrodeposition is impossible or the electrodeposition rate decreases. Pre-adding a salt of the acid contained in the acid solution makes it possible to suppress concentration-diffusion of the acid from the acid solution. Adding a salt of the acid into the cathode chamber makes it possible to reduce the impressed voltage, reduce the amount of hydrogen generated on the cathode, and reduce the amount of power.

Provided is a method for efficiently producing tungsten from a raw material mixture comprising at least one valuable containing tungsten. The present invention relates to a method for producing tungsten, comprising the steps of subjecting a raw material mixture comprising at least one valuable containing tungsten to electrolysis using an organic electrolytic solution to dissolve tungsten in the electrolytic solution; and calcining the electrolytic solution containing dissolved tungsten at a temperature of less than 800 C. to obtain tungsten.