Method and arrangement for producing metal powder

Abstract

In a method for producing metal powder, the first part of an acid-containing starting solution is fed on the anode side of an electrolytic cell as anolyte, to contact the anode and supply material containing yield metal, and a second part of the acid-containing starting solution, which also contains intermediary metal, is fed on the cathode side of the electrolytic cell, to contact the cathode as catholyte. Yield metal is oxidized and dissolved in the anolyte by leading electric current in the anode. The yield metal contained in the second part of the starting solution is reduced on the cathode side. Anolyte solution and catholyte solution are fed to a precipitating chamber for mixing the dissolved, oxidized yield metal and the second part of the starting solution containing reduced intermediary metal.

1 . A method for manufacturing metal powder, wherein dissolved yield metal is mixed with a solution containing at least one intermediary metal for precipitating the dissolved yield metal into yield metal powder ( 14 ),
 wherein in the method
 a first part of an acid-containing starting solution is brought as an anolyte ( 1 ) to the anode side ( 6 ) of an electrolytic cell, to be in contact with the anode ( 2 ) and the supply material containing yield metal; and a second part of the acid-containing starting solution, which also contains intermediary metal in addition to acid, is brought to the cathode side ( 8 ) of the electrolytic cell, as a catholyte ( 3 ) to be in contact with the cathode ( 4 ); 
 the yield metal is oxidized and dissolved in the anolyte ( 1 ) by conducting electric current in the anode ( 2 ); 
 the intermediary metal contained in the second part of the starting solution is reduced on the cathode side ( 8 ); and 
 anolyte solution and catholyte solution are brought into a precipitation chamber ( 12 ) for mixing the oxidized yield metal dissolved in the first part of the starting solution and the second part of the starting solution containing reduced intermediary metal. 
   
     
     
         2 . A method according to  claim 1 , wherein the first part of the starting solution contains intermediary metal for boosting the dissolution of yield metal on the anode side. 
     
     
         3 . A method according to  claim 1 , wherein the first part of the circulating solution created as a result of mixing the anolyte solution and the catholyte solution is returned back to anolyte ( 1 ). 
     
     
         4 . A method according to  claim 3 , wherein the first part of the starting solution is composed of the first part of the circulating solution. 
     
     
         5 . A method according to  claim 3 , wherein the second part of the circulating solution created as a result of mixing the anolyte solution and the catholyte solution is returned back to catholyte ( 3 ). 
     
     
         6 . A method according to  claim 5 , wherein the second part of the starting solution is composed of the second part of the circulating solution. 
     
     
         7 . A method according to  claim 5 , wherein the circulating solution is conducted essentially completely back to electrolyte, so that the circulating solution is essentially composed of a first part of the circulating solution and of a second part of the circulating solution. 
     
     
         8 . A method according to  claim 1 , wherein the anolyte ( 1 ) and the catholyte ( 3 ) are mechanically separated by an electroconductive diaphragm ( 7 ). 
     
     
         9 . A method according to  claim 1 , wherein electroconductive separator solution ( 5 ) is conducted in between the two diaphragms ( 7 ) separating the anolyte ( 1 ) and the catholyte ( 3 ) in order to prevent a premature mixing of the anolyte ( 1 ) and the catholyte ( 3 ). 
     
     
         10 . A method according to  claim 1 , wherein the yield metal is copper. 
     
     
         11 . A method according to  claim 1 , wherein the yield metal is selected among the following group: nickel, cobalt, zinc, silver, gold, ruthenium, rhodium, palladium, osmium, iridium, platinum, manganese, zirconium, tin, cadmium and indium. 
     
     
         12 . A method according to  claim 1 , wherein the intermediary metal is vanadium. 
     
     
         13 . A method according to  claim 1 , wherein the intermediary metal is selected among the group titanium, chromium and iron. 
     
     
         14 . A method according to  claim 1 , wherein the intermediary metal is selected among the following group:
 manganese, zirconium, molybdenum, technetium, tungsten, quicksilver, germanium, arsenic, selenium, tin, antimony, tellurium and copper.   
     
     
         15 . A method according, to  claim 1 , wherein the supply material containing yield metal is located in the anode ( 2 ). 
     
     
         16 . A method according to  claim 1 , wherein the yield metal is selected so that the chosen yield metal is dissolved in the anolyte ( 1 ) as a soluble salt of the acid that is contained in the first part of the starting solution. 
     
     
         17 . A method according to  claim 1 , wherein the starting solution contains sulfuric acid. 
     
     
         18 . A method according to  claim 1 , wherein the content of sulfuric acid in the starting solution is at least 50 g/l and preferably 50 g/l-1500 g/l. 
     
     
         19 . A method according to  claim 1 , wherein the starting solution contains hydrochloric acid or nitric acid. 
     
     
         20 . An arrangement for producing metal powder by precipitating yield metal powder ( 14 ) by mixing dissolved yield metal with a solution containing at least one intermediary metal, wherein the arrangement comprises an electrolytic cell for dissolving the yield metal located on the anode side of the electrolytic cell and for oxidizing it in the anolyte, and for reducing the dissolved intermediary metal located on the cathode side ( 8 ) of the electrolytic cell on the cathode side; a precipitating chamber ( 12 ) that is essentially separate from the electrolytic cell; as well as means for feeding anolyte solution and catholyte solution respectively from the anode side ( 6 ) of the electrolytic cell and from the cathode side ( 8 ) of the electrolytic cell to the precipitating chamber ( 12 ) for mixing the yield metal dissolved in the anolyte and the catholyte solution containing reduced intermediary metal, from outside the electrolytic cell. 
     
     
         21 . An arrangement according to  claim 20 , wherein the electrolytic cell comprises an electroconductive diaphragm ( 7 ) in between the anode side ( 6 ) and the cathode side ( 8 ) of the electrolytic cell for mechanically separating the anode side ( 6 ) and the cathode side ( 8 ). 
     
     
         22 . A method according to  claim 20 , wherein the electrolytic cell comprises two electroconductive diaphragms ( 7 ) in between the anode side ( 6 ) and cathode side ( 8 ) of the electrolytic cell for mechanically separating the anode side ( 6 ) and the cathode side ( 8 ) by means of an electroconductive separator solution ( 5 ) provided in the space left between the two diaphragms ( 7 ). 
     
     
         23 . A method according to  claim 20 , wherein the yield metal supplied on the anode side ( 6 ) of the electrolytic cell is located in the anode ( 2 ) of the electrolytic cell. 
     
     
         24 . A method according to  claim 20 , wherein the electrolytic cell comprises at least one bag, defined by a diaphragm ( 7 ), for keeping the anolyte and/or the catholyte inside the bag. 
     
     
         25 . A method according to  claim 20 , wherein the electrolytic cell comprises means for conducting a separator solution ( 5 ) from the space left between the two diaphragms ( 7 ) to the anode side ( 6 ) and/or to the cathode side ( 8 ). 
     
     
         26 . A method according to  claim 20 , wherein the electrolytes are placed in an oxygen-free environment for preventing the oxidation of the yield metal and/or intermediary metal contained in the electrolytes.