Anode for electrowinning and method for electrowinning using same

Abstract

Provided is an anode for electrowinning in a sulfuric acid based electrolytic solution. The anode produces oxygen at a lower potential than a lead electrode, lead alloy electrode, and coated titanium electrode, thereby enabling electrowinning to be performed at a reduced electrolytic voltage and the electric power consumption rate of a desired metal to be reduced. The anode is also available as an anode for electrowinning various types of metals in volume with efficiency. The anode is employed for electrowinning in a sulfuric acid based electrolytic solution and adopted such that a catalyst layer containing amorphous ruthenium oxide and amorphous tantalum oxide is formed on a conductive substrate.

1 . An anode comprising:
 a conductive substrate, and   a catalytic layer comprising amorphous ruthenium oxide and amorphous tantalum oxide disposed on the conductive substrate.   
     
     
         2 . The anode of  claim 1 , which is suitable for use in a process of electrowinning in a sulfuric acid based electrolytic solution, wherein the electrowinning is performed at an electrolytic voltage reduced by 0.02 V or greater when compared to an anode with a catalytic layer of amorphous iridium oxide and amorphous tantalum oxide disposed on a conductive substrate, or wherein the electrowinning is performed at an electrolytic voltage reduced by 0.05 V or greater when compared to an anode with a catalytic layer of crystalline ruthenium oxide and amorphous tantalum oxide disposed on a conductive substrate. 
     
     
         3 . (canceled) 
     
     
         4 . The anode of  claim 1 , wherein a molar ratio between ruthenium and tantalum in the catalytic layer is 30:70. 
     
     
         5 . The anode of  claim 1 , further comprising an intermediate layer between the catalytic layer and the conductive substrate. 
     
     
         6 . The anode of  claim 5 , wherein the intermediate layer comprises a metal selected from the group consisting of tantalum, niobium, tungsten, molybdenum, titanium, and platinum, or comprises an alloy of the metal. 
     
     
         7 . The anode of  claim 5 , wherein the intermediate layer comprises crystalline iridium oxide and amorphous tantalum oxide. 
     
     
         8 . (canceled) 
     
     
         9 . A method for electrowinning, comprising:
 contacting the anode of  claim 1  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         10 . (canceled) 
     
     
         11 . The anode of  claim 2 , wherein a molar ratio between ruthenium and tantalum in the catalytic layer is 30:70. 
     
     
         12 . The anode of  claim 2 , further comprising an intermediate layer between the catalytic layer and the conductive substrate. 
     
     
         13 . The anode of  claim 4 , further comprising an intermediate layer between the catalytic layer and the conductive substrate. 
     
     
         14 . The anode of  claim 11 , further comprising an intermediate layer between the catalytic layer and the conductive substrate. 
     
     
         15 . The anode of  claim 12 , wherein the intermediate layer comprises a metal selected from the group consisting of tantalum, niobium, tungsten, molybdenum, titanium, and platinum, or comprises an alloy of the metal. 
     
     
         16 . The anode of  claim 13 , wherein the intermediate layer comprises a metal selected from the group consisting of tantalum, niobium, tungsten, molybdenum, titanium, and platinum, or comprises an alloy of the metal. 
     
     
         17 . The anode of  claim 14 , wherein the intermediate layer comprises a metal selected from the group consisting of tantalum, niobium, tungsten, molybdenum, titanium, and platinum, or comprises an alloy of the metal. 
     
     
         18 . The anode of  claim 12 , wherein the intermediate layer comprises crystalline iridium oxide and amorphous tantalum oxide. 
     
     
         19 . The anode of  claim 13 , wherein the intermediate layer comprises crystalline iridium oxide and amorphous tantalum oxide. 
     
     
         20 . The anode of  claim 14 , wherein the intermediate layer comprises crystalline iridium oxide and amorphous tantalum oxide. 
     
     
         21 . A method for electrowinning, comprising:
 contacting the anode of  claim 2  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         22 . A method for electrowinning, comprising:
 contacting the anode of  claim 4  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         23 . A method for electrowinning, comprising:
 contacting the anode of  claim 5  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         24 . A method for electrowinning, comprising:
 contacting the anode of  claim 6  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         25 . A method for electrowinning, comprising:
 contacting the anode of  claim 7  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         26 . A method for electrowinning, comprising:
 contacting the anode of  claim 11  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         27 . A method for electrowinning, comprising:
 contacting the anode of  claim 12  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         28 . A method for electrowinning, comprising:
 contacting the anode of  claim 13  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         29 . A method for electrowinning, comprising:
 contacting the anode of  claim 14  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         30 . A method for electrowinning, comprising:
 contacting the anode of  claim 15  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         31 . A method for electrowinning, comprising:
 contacting the anode of  claim 16  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         32 . A method for electrowinning, comprising:
 contacting the anode of  claim 17  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         33 . A method for electrowinning, comprising:
 contacting the anode of  claim 18  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         34 . A method for electrowinning, comprising:
 contacting the anode of  claim 19  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         35 . A method for electrowinning, comprising:
 contacting the anode of  claim 20  with an electrolytic solution comprising sulfuric acid and a desired metal, and   extracting the desired metal from the electrolytic solution.   
     
     
         36 . An anode comprising:
 a conductive substrate, and   a catalytic layer consisting of amorphous ruthenium oxide and amorphous tantalum oxide disposed on the conductive substrate.