A problem to be solved is to provide a method for regenerating plating liquid from plating waste liquid in a simple and easy way and a plating method utilizing the regenerating method. A method for regenerating plating liquid from plating waste liquid that is produced as a result of performing a copper plating on steel and that contains respective ions of Fe, Cu and Sn comprises repetitively performing processing steps of applying electric current with the plating waste liquid 11 side taken as a cathode 15 and electrolytic solution 12 side taken as an anode 16 in the state that the plating waste liquid 11 and the electrolytic solution 12 are connected through an anion exchange membrane 13; separating copper by making a copper deposition electrode as a result of depositing copper on the cathode 15 being in contact with the plating waste liquid 11, to turn the plating waste liquid to processed remaining liquid; and using as the anode 16 a copper deposition electrode formed previously and dissolving copper in the electrolytic solution 12 to generate copper ion-containing solution.

An electrolysis apparatus for the production of iron through reduction of iron ore by an electrolysis reaction, the electrolysis reaction emitting a gas, the apparatus including a casing. The casing including a gas permeable anode plate being made of a cellular material, a cathode plate, both facing each other and being separated by an electrolyte chamber.

An electrolysis apparatus for the production of iron through reduction of iron ore by an electrolysis reaction, the electrolysis reaction emitting a gas, the apparatus including a casing. The casing including a gas permeable anode plate being made of a cellular material, a cathode plate, both facing each other and being separated by an electrolyte chamber.

An electrochemical reactor, including a channel for containing and directing flow of an electrolyte stream, wherein the electrolyte stream includes an electrolyte and an iron-containing feedstock; an anode and a cathode positioned in contact with the channel; and a source of a magnetic field positioned in proximity to the cathode, wherein the electrochemical reactor is configured to electrochemically reduce at least a portion of the iron-containing feedstock to iron metal at a surface of the cathode and in a magnetic field of the source, and wherein the at least a portion of the iron-containing feedstock is electrochemically reduced to the iron metal at a current efficiency of at least 0.75, wherein the current efficiency is a ratio of charge used for the reduction of the iron-containing feedstock to a total charge provided to the cathode.

An electrochemical reactor, including a channel for containing and directing flow of an electrolyte stream, wherein the electrolyte stream includes an electrolyte and an iron-containing feedstock; an anode and a cathode positioned in contact with the channel; and a source of a magnetic field positioned in proximity to the cathode, wherein the electrochemical reactor is configured to electrochemically reduce at least a portion of the iron-containing feedstock to iron metal at a surface of the cathode and in a magnetic field of the source, and wherein the at least a portion of the iron-containing feedstock is electrochemically reduced to the iron metal at a current efficiency of at least 0.75, wherein the current efficiency is a ratio of charge used for the reduction of the iron-containing feedstock to a total charge provided to the cathode.

An electrochemical reactor comprising a source of a magnetic field positioned in proximity to a cathode and configured to generate a magnetic field; and an electrochemical cell comprising an anode and the cathode, and further comprising a catholyte channel configured to direct a catholyte stream comprising an iron-containing feedstock to the cathode; an anolyte channel configured to direct an anolyte stream comprising a metal chloride to the anode, wherein the catholyte channel and the anolyte channel are disposed between the cathode and the anode; and a separator disposed between the catholyte channel and the anolyte channel, wherein the electrochemical reactor is configured to electrochemically oxidize chloride anions to chlorine gas at a surface of the anode, and wherein the electrochemical reactor is further configured to electrochemically reduce the iron-containing feedstock to an iron particle comprising iron metal at the surface of the cathode and in the magnetic field.

An electrochemical reactor comprising a source of a magnetic field positioned in proximity to a cathode and configured to generate a magnetic field; and an electrochemical cell comprising an anode and the cathode, and further comprising a catholyte channel configured to direct a catholyte stream comprising an iron-containing feedstock to the cathode; an anolyte channel configured to direct an anolyte stream comprising a metal chloride to the anode, wherein the catholyte channel and the anolyte channel are disposed between the cathode and the anode; and a separator disposed between the catholyte channel and the anolyte channel, wherein the electrochemical reactor is configured to electrochemically oxidize chloride anions to chlorine gas at a surface of the anode, and wherein the electrochemical reactor is further configured to electrochemically reduce the iron-containing feedstock to an iron particle comprising iron metal at the surface of the cathode and in the magnetic field.

A method of recovering metals from electronic waste comprises providing a powder comprising electronic waste in at least a first reactor and a second reactor and providing an electrolyte comprising at least ferric ions in an electrochemical cell in fluid communication with the first reactor and the second reactor. The method further includes contacting the powders within the first reactor and the second reactor with the electrolyte to dissolve at least one base metal from each reactor into the electrolyte and reduce at least some of the ferric ions to ferrous ions. The ferrous ions are oxidized at an anode of the electrochemical cell to regenerate the ferric ions. The powder within the second reactor comprises a higher weight percent of the at least one base metal than the powder in the first reactor. Additional methods of recovering metals from electronic waste are also described, as well as an apparatus of recovering metals from electronic waste.

A method of recovering metals from electronic waste comprises providing a powder comprising electronic waste in at least a first reactor and a second reactor and providing an electrolyte comprising at least ferric ions in an electrochemical cell in fluid communication with the first reactor and the second reactor. The method further includes contacting the powders within the first reactor and the second reactor with the electrolyte to dissolve at least one base metal from each reactor into the electrolyte and reduce at least some of the ferric ions to ferrous ions. The ferrous ions are oxidized at an anode of the electrochemical cell to regenerate the ferric ions. The powder within the second reactor comprises a higher weight percent of the at least one base metal than the powder in the first reactor. Additional methods of recovering metals from electronic waste are also described, as well as an apparatus of recovering metals from electronic waste.

A method for separating an amount of osmium from a mixture containing the osmium and at least one other additional metal is provided. In particular, method for forming and trapping OsO.sub.4 to separate the osmium from a mixture containing the osmium and at least one other additional metal is provided.