A method of purifying an alkaline electrolyte includes contacting the alkaline electrolyte with an aluminum compound to provide a purified alkaline electrolyte. The alkaline electrolyte includes a metal hydroxide, a compound comprising aluminum, silicon, or a combination thereof, and a solvent. The method can be particularly advantageous when used with a method of processing an iron-containing feedstock.

An electrochemical cell for converting metal salt or metal oxide to metal comprises: a) a mixture comprising an electrolyte and metal salt or metal oxide; b) an anode submerged in the mixture; c) a cathode partially submerged in the mixture and moveable along a closed loop path; and d) a harvester disposed at an exposed portion of the cathode outside of the mixture, wherein an electrical charge supplied to the electrochemical cell reduces the metal salt or metal oxide to metal at and disposed onto the cathode, and wherein the harvester removes the metal from the exposed portion of the cathode. Methods and systems for converting metal salt or metal oxide to metal are also disclosed including continuous methods and systems.

An electrochemical cell for converting metal salt or metal oxide to metal comprises: a) a mixture comprising an electrolyte and metal salt or metal oxide; b) an anode submerged in the mixture; c) a cathode partially submerged in the mixture and moveable along a closed loop path; and d) a harvester disposed at an exposed portion of the cathode outside of the mixture, wherein an electrical charge supplied to the electrochemical cell reduces the metal salt or metal oxide to metal at and disposed onto the cathode, and wherein the harvester removes the metal from the exposed portion of the cathode. Methods and systems for converting metal salt or metal oxide to metal are also disclosed including continuous methods and systems.

Methods and systems for producing iron from an iron-containing ore and removing impurities found in the iron-containing ore are disclosed. For example, a method for producing iron comprises providing a feedstock having an iron-containing ore and one or more impurities to a dissolution subsystem comprising a first electrochemical cell; producing an iron-rich solution, in the dissolution subsystem; treating the iron-rich solution to remove at least a portion of one or more impurities by raising a pH of the iron-rich solution from an initial pH to an adjusted pH thereby precipitating at least a portion of the one or more impurities in the treated iron-rich solution; delivering the treated iron-rich solution to an iron-plating subsystem having a second electrochemical cell; second electrochemically reducing at least a first portion of the transferred formed Fe.sup.2+ ions to Fe metal; and removing the Fe metal from the second electrochemical cell thereby producing iron.

Methods and systems for producing iron from an iron-containing ore and removing impurities found in the iron-containing ore are disclosed. For example, a method for producing iron comprises providing a feedstock having an iron-containing ore and one or more impurities to a dissolution subsystem comprising a first electrochemical cell; producing an iron-rich solution, in the dissolution subsystem; treating the iron-rich solution to remove at least a portion of one or more impurities by raising a pH of the iron-rich solution from an initial pH to an adjusted pH thereby precipitating at least a portion of the one or more impurities in the treated iron-rich solution; delivering the treated iron-rich solution to an iron-plating subsystem having a second electrochemical cell; second electrochemically reducing at least a first portion of the transferred formed Fe.sup.2+ ions to Fe metal; and removing the Fe metal from the second electrochemical cell thereby producing iron.

A method for the electrochemical recovery of a metal from a spent electrode is provided. The method comprises the steps of providing an electrochemical cell comprising a metal recovery electrode as a working electrode, the spent electrode as a counter-electrode, and an electrolyte between the working electrode and the counter-electrode, and performing cyclic voltammetry on the metal recovery electrode, thereby dissolving the metal from the spent electrode and adsorbing dissolved atoms of the metal on the metal recovery electrode, thereby recovering the metal and forming a composite electrode. The metal recovery electrode comprising a metal compound on a conducting support and the metal compound is made by a method comprising reacting a metal oxalate or an ammonium metal oxalate, wherein the metal is a group 4 to 6 metal, with a chalcogenide or an organochalcogenide.

A method for the electrochemical recovery of a metal from a spent electrode is provided. The method comprises the steps of providing an electrochemical cell comprising a metal recovery electrode as a working electrode, the spent electrode as a counter-electrode, and an electrolyte between the working electrode and the counter-electrode, and performing cyclic voltammetry on the metal recovery electrode, thereby dissolving the metal from the spent electrode and adsorbing dissolved atoms of the metal on the metal recovery electrode, thereby recovering the metal and forming a composite electrode. The metal recovery electrode comprising a metal compound on a conducting support and the metal compound is made by a method comprising reacting a metal oxalate or an ammonium metal oxalate, wherein the metal is a group 4 to 6 metal, with a chalcogenide or an organochalcogenide.

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.

A low heat, electrochemical cascade process generates iron metal (Fe.sub.2) from iron ore and a sequence of alkaline electrolytic solutions. An intermediate phase favors iron oxide in a layered double hydroxide (LDH) form resulting from conditioning silicates in the alkaline solution over chemically inert Fe.sub.3O.sub.4 formation. The alkaline electrolytic solution mitigates production of hydrogen gas over acidic approaches by inhibiting a hydrogen evolution reaction (HER) that forms parasitic hydrogen gas. An electrolyte containment generates an electrolyte flow for the cascading electrochemical reaction as the raw iron oxide transforms to iron metal while avoiding conventional shortcomings of low value products of Fe.sub.3O.sub.4 (magnetite) and hydrogen gas, and instead favors generation of iron metal. Additional electrolyte salts can further form iron alloys.