The invention relates to a combined electrolytic system for precipitating different types of metals (copper, zinc, nickel, cadmium, cobalt, silver, gold) and regenerating reagents for the leaching of metal sulphurs from solutions from leaching in a sulphuric-oxidising or hydrochloric-oxidising environment, including a process that permits the combining of the current reduction processes followed by oxidising processes which are complex and potentially dangerous from an environmental point of view, thereby preventing the risky transportation of dangerous substances, loading and unloading operations, storage and manipulation of toxic materials, and reducing the environmentally contaminating waste, producing a commercial-quality cathodic product and a solution that is re-used in the leaching process. The system comprises a membrane cell device (3) that is connected via ducts and valves to one or more oxidising agent tanks (7), to one or more anodic solution tanks (6) and to one or more cathodic solution tanks (2), wherein said membrane device (3) is formed by one or more cathodic compartments (4) and by one or more anode compartments (5), wherein each of the cathodic compartment(s) (4) is/are separated from each of the anode compartment(s) (5) by a membrane for selective and uni-directional ion exchange.

The invention relates to a combined electrolytic system for precipitating different types of metals (copper, zinc, nickel, cadmium, cobalt, silver, gold) and regenerating reagents for the leaching of metal sulphurs from solutions from leaching in a sulphuric-oxidising or hydrochloric-oxidising environment, including a process that permits the combining of the current reduction processes followed by oxidising processes which are complex and potentially dangerous from an environmental point of view, thereby preventing the risky transportation of dangerous substances, loading and unloading operations, storage and manipulation of toxic materials, and reducing the environmentally contaminating waste, producing a commercial-quality cathodic product and a solution that is re-used in the leaching process. The system comprises a membrane cell device (3) that is connected via ducts and valves to one or more oxidising agent tanks (7), to one or more anodic solution tanks (6) and to one or more cathodic solution tanks (2), wherein said membrane device (3) is formed by one or more cathodic compartments (4) and by one or more anode compartments (5), wherein each of the cathodic compartment(s) (4) is/are separated from each of the anode compartment(s) (5) by a membrane for selective and uni-directional ion exchange.

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.

This invention relates to a metal catalyst, a manufacturing method of the metal catalyst, and an electrochemical reduction method. The metal catalyst is manufactured by a method comprising providing a conductor to one side of an insulator, providing a fluid including a metal ion and an electron mediator to the other side of the insulator and providing a voltage to the conductor. The electrochemical reduction method comprises providing a conductor to one side of an insulator, providing a fluid including reduction material and an electron mediator to the other side of the insulator and providing a voltage to the conductor.

This invention relates to a metal catalyst, a manufacturing method of the metal catalyst, and an electrochemical reduction method. The metal catalyst is manufactured by a method comprising providing a conductor to one side of an insulator, providing a fluid including a metal ion and an electron mediator to the other side of the insulator and providing a voltage to the conductor. The electrochemical reduction method comprises providing a conductor to one side of an insulator, providing a fluid including reduction material and an electron mediator to the other side of the insulator and providing a voltage to the conductor.

A new dendritic silver powder can be mixed with a synthetic resin to give electroconductive films having sufficient electroconductivity. Even when the films vary in thickness, the electroconductivity of the films can be maintained. The volume-cumulative particle diameter D50 (referred to as D50D) determined by adding the silver powder to water containing a dispersant, applying 300-watt ultrasonic waves to the resultant mixture for 3 minutes, and examining the dispersion with a laser diffraction/scattering type particle size analyzer is 1.0-15.0 m and that the ratio of the volume-cumulative particle diameter D50 (referred to as D50N) determined by adding the silver powder to the water containing a dispersant and examining the mixture under the same conditions as for the D50D except that no ultrasonic waves are applied, to the D50D, D50N/D50D, is 1.0-10.0.

The present invention relates to a process for recovering platinum group metals from a feed containing one or more precursor compounds of one or more platinum group metal ions, wherein the process comprises the steps of (i) supplying to a cathode compartment of an electrochemical cell equipped with a cathode comprising a gas diffusion electrode with a porous electrochemically active material, the feed containing the one or more precursor compounds to form a liquid phase in the cathode compartment, (ii) supplying a CO2 containing gas to the cathode compartment, (iii) applying a potential to the cathode which is such as to cause electrochemical reduction of the CO2 to CO, (iv) and recovering from the liquid phase precipitated particles of the one or more platinum group metals in clemental form.

The present invention relates to a process for recovering platinum group metals from a feed containing one or more precursor compounds of one or more platinum group metal ions, wherein the process comprises the steps of (i) supplying to a cathode compartment of an electrochemical cell equipped with a cathode comprising a gas diffusion electrode with a porous electrochemically active material, the feed containing the one or more precursor compounds to form a liquid phase in the cathode compartment, (ii) supplying a CO2 containing gas to the cathode compartment, (iii) applying a potential to the cathode which is such as to cause electrochemical reduction of the CO2 to CO, (iv) and recovering from the liquid phase precipitated particles of the one or more platinum group metals in clemental form.

Systems and methods for producing metal chloride M.sup.ICl.sub.x from metal M.sup.I without the use of HCl and/or Cl.sub.2 gases, including: a bath vessel holding conductive fluid; an anode disposed in the conductive fluid, the anode including metal M.sup.I; a cathode assembly disposed in the conductive fluid, the cathode assembly including a cathode vessel including porous and non-porous portions, the non-porous portion holding sacrificial metal chloride M.sup.IICl.sub.y substantially separate from metal chloride M.sup.ICl.sub.x, wherein the cathode assembly includes a center lead disposed within the cathode vessel operable for delivering charge to sacrificial metal chloride M.sup.IICl.sub.y; and a power supply coupling the anode and the cathode assembly, the power supply polarized to produce current flow in a direction that causes anodic dissolution of metal M.sup.I into the conductive fluid and deposition of metal M.sup.II within the cathode vessel. The systems and methods apply equally to producing metal halide M.sup.IX.sub.x.