IL43733A - Method of electrodeposition of metals using catalyzed hydrogen - Google Patents

Claims (2)

1. CLAIMS : 5. A method of depositing a metal of oxidation potential below and thus reducible by hydrogen from an acidic salt solution thereof, that comprises, disposing a hydrogen-ionizing catalyst in ionic but not physical contact with said solution, passing hydrogen along said catalyst to activate the hydrogen, establishing an electrically conductive path external to said solution between said catalyst, acting as a hydrogen anode, and a conductive surface in said solution, acting as an electro-deposition cathode, in order to produce a electrochemical cell , generating an electric current within said cell without requiring an external power supply and passing said current along said path in order to deposit elemental metal upon said conductive surface within said solution while maintaining the metal ions of said solution and the reduced metal from physical contact with said catalyst, said maintaining step comprising interposing a porous diffusion barrier between said solution and said catalyst and flowing an acidic solution through said diffusion barrier into said salt solution from the catalyst side of the barrier to prevent the flow of metal ions and reduced metal in the opposite direction through the barrier toward said catalyst.
2. 2. A method as claimed in claim 1 and in which an electrically conductive path is established external to said solution between said catalyst surface , acting as an electro-deposition cathode; A rethod as claimed in claim 1 or 2 and in which said maintaining step comprises interposing a diffusion barrier between said solution and said catalyst surface and flowing an acidic solution through said diffusion barrier into said salt solution from the catalyst surface side of the barrier to prevent the flow of metal ions and reduced metal in the opposite direction through the barrier toward said catalyst surface. 4. A method as claimed in claim 3 and in which the said metal is selected from the group consisting of copper, silver, mercury and the oble metals. 5. A method of depositing a metal of oxidation potential below and thus reducible by hydrogen from a salt solution thereof, that compriooa, dlnpoain# a hydro#on-loni¾in# catalyst unodo ourface in Ionic but not phyoical contact with said solution, passing hydrogen along said surface to activate the hydrogen, disposing a conductive cathode surface within said solution, establishing an electrically conductive path between the anode and cathodic surfaces external to said solution to produce an electrochemical cell, generating an electric current within said cell without requiring an external power supply and passing said current along said path in order to deposit the metal from said solution with the aid of the action of said activated hydrogen, interposing a porous diffusion barrier between said solution and said anode surface, and flowing a solution across said barrier from the anode side thereof to prevent the flow of ions of the metal and the metal in the opposite direction through the barrier. 6. A met d of depositing copper from an acidic copper εζΐτ solution, that comprj.Mon, d n ontng a hydrogen-ionizing catalyst in ionic but not physical contact with said solution, passing hydrogen along said catalyst to activate the hydrogen, causing the activated hydrogen to reduce the copper in said solution to elemental copper, and establishing external to the solution an electrically conductive path between said catalyst and a conducting surface in said solution in order to form an electrochemical cell, generating an electric current within said cell without requiring an external power supply and passing said current along said path in order to deposit the elemental copper upon said conductive surface within said solution, and maintaining the copper ions of said solution and the reduced copper from physical contact with said catalyst by flowing an acidic solution through a porous diffusion barrier into said salt solution from the catalyst side of the barrier. 7. A method as claimed in claim 6 and in which said conductive surface comprises a copper surface. θ. Λ method txa clulmod in claim 6 or 7 and in which piaid catalyst is selected from the group consiting of platinum, palladium and a combination of the same. 9. A method as claimed in any of claims 6 to 8 and in which an electrically conductive path is established external to said solution between said catalyst surface and said conductive surface to cause the said catalyst surface to act as a hydrogen anode and the said conductive surface to act as an electro-deposition cathode and to produce electrochemical cell action therebetween. 10. A nuHivv. n claimed in claim 9 and in which said maintaining step comprises interposing a diffusion . barrier between said solution and said catalyst surface^ and flowing an acidic solution through said diffusion barrier into said salt solution from the catalyst surface side of the barrier to prevent the flow of copper ions '· and reduced copper in the opposite direction through the barrier toward said catalyst surface. ,- 11. Λ method as claimed in claim 10 and in which said \ acidic solution comprises sulphuric acid., 12. A method as claimed in claim 9 or 10 and in which said salt solution comprises copper sulphate and said conductive surface comprises a copper surface. 13. Method of depositing a metal from an acidic solution thereof, substantially as hereinbefore described and with reference to the examples. H. Metals, whenever obtained by a method as claimed in any of Claims .1 to 13. For ApplicantsI