Chlorine evolution anode

Abstract

Provided is a chlorine evolution method which includes contacting an anode with chloride based aqueous solution and generating chlorine as a main reaction at the anode, in which a main reaction of the anode is chlorine evolution, and the chlorine evolution anode which is low in potential of the anode for chlorine evolution, thereby being able to decrease an electrolytic voltage and lower an electric energy consumption rate. The chlorine evolution anode of the present invention is a chlorine evolution anode in which chlorine evolution from an aqueous solution is a main reaction of the anode and also in which a catalytic layer containing amorphous ruthenium oxide and amorphous tantalum oxide is formed on a conductive substrate.

1 . A chlorine evolution method comprising:
 contacting an anode with chloride based aqueous solution; and   generating chlorine as a main reaction at the anode,   wherein the anode comprises a catalytic layer containing amorphous ruthenium oxide and amorphous tantalum oxide formed on a conductive substrate, the catalytic layer contains no crystalline ruthenium oxide that is detectable by X-ray diffraction analysis, and the catalytic layer contains no crystalline tantalum oxide that is detectable by X-ray diffraction analysis.   
     
     
         2 . The chlorine evolution method according to  claim 1 , wherein the catalytic layer is composed of a mixture of amorphous ruthenium oxide and amorphous tantalum oxide. 
     
     
         3 . The chlorine evolution method according to  claim 1 , wherein a mole ratio of ruthenium to tantalum is from 90:10 to 10:90 in the catalytic layer. 
     
     
         4 . The chlorine evolution method according to  claim 1 , wherein the anode further comprises an intermediate layer between the catalytic layer and the conductive substrate. 
     
     
         5 . The chlorine evolution method according to  claim 4 , wherein the intermediate layer is made of tantalum, niobium, tungsten, molybdenum, titanium, platinum or any one of alloys of these metals. 
     
     
         6 . The chlorine evolution method according to  claim 4 , wherein the intermediate layer contains a crystalline composite oxide of ruthenium and titanium. 
     
     
         7 . The chlorine evolution method according to  claim 4 , wherein the intermediate layer contains crystalline ruthenium oxide and amorphous tantalum oxide. 
     
     
         8 . The chlorine evolution method according to  claim 4 , wherein the intermediate layer is electrically conductive diamond. 
     
     
         9 . The chlorine evolution method according to  claim 2 , wherein a mole ratio of ruthenium to tantalum is from 90:10 to 10:90 in the catalytic layer. 
     
     
         10 . The chlorine evolution method according to  claim 2 , wherein the anode further comprises an intermediate layer between the catalytic layer and the conductive substrate. 
     
     
         11 . The chlorine evolution method according to  claim 3 , wherein the anode further comprises an intermediate layer between the catalytic layer and the conductive substrate. 
     
     
         12 . The chlorine evolution method according to  claim 9 , wherein the anode further comprises an intermediate layer between the catalytic layer and the conductive substrate. 
     
     
         13 . The chlorine evolution method according to  claim 10 , wherein the intermediate layer is made of tantalum, niobium, tungsten, molybdenum, titanium, platinum or any one of alloys of these metals. 
     
     
         14 . The chlorine evolution method according to  claim 11 , wherein the intermediate layer is made of tantalum, niobium, tungsten, molybdenum, titanium, platinum or any one of alloys of these metals. 
     
     
         15 . The chlorine evolution method according to  claim 12 , wherein the intermediate layer is made of tantalum, niobium, tungsten, molybdenum, titanium, platinum or any one of alloys of these metals. 
     
     
         16 . The chlorine evolution method according to  claim 10 , wherein the intermediate layer contains a crystalline composite oxide of ruthenium and titanium. 
     
     
         17 . The chlorine evolution method according to  claim 11 , wherein the intermediate layer contains a crystalline composite oxide of ruthenium and titanium. 
     
     
         18 . The chlorine evolution method according to  claim 12 , wherein the intermediate layer contains a crystalline composite oxide of ruthenium and titanium. 
     
     
         19 . The chlorine evolution method according to  claim 10 , wherein the intermediate layer contains crystalline ruthenium oxide and amorphous tantalum oxide. 
     
     
         20 . The chlorine evolution method according to  claim 11 , wherein the intermediate layer contains crystalline ruthenium oxide and amorphous tantalum oxide. 
     
     
         21 . The chlorine evolution method according to  claim 12 , wherein the intermediate layer contains crystalline ruthenium oxide and amorphous tantalum oxide. 
     
     
         22 . The chlorine evolution method according to  claim 10 , wherein the intermediate layer is electrically conductive diamond. 
     
     
         23 . The chlorine evolution method according to  claim 11 , wherein the intermediate layer is electrically conductive diamond. 
     
     
         24 . The chlorine evolution method according to  claim 12 , wherein the intermediate layer is electrically conductive diamond. 
     
     
         25 . The chlorine evolution method according to  claim 1 , wherein the catalytic layer contains no crystalline ruthenium oxide and no crystalline tantalum oxide. 
     
     
         26 . A chlorine evolution method comprising:
 contacting an anode with chloride based aqueous solution; and   generating chlorine as a main reaction at the anode,   wherein the anode comprises a catalytic layer containing amorphous ruthenium oxide and amorphous tantalum oxide formed on a conductive substrate.