Method for producing fluorine gas and device for producing fluorine gas

Abstract

A method for producing fluorine gas including electrolyzing an electrolyte in an electrolytic cell, measuring the water concentration in the electrolyte in the electrolyzing, and sending a fluid generated in the inside of the electrolytic cell in the electrolyzing the electrolyte, from the inside to the outside of the electrolytic cell through a flow path. The flow path in which the fluid flows is switched in accordance with the water concentration in the electrolyte measured in the measuring the water concentration, such that the fluid is sent to a first flow path when the water concentration in the electrolyte measured in the measuring the water concentration is not more than a predetermined reference value, or the fluid is sent to a second flow path when the water concentration is more than the predetermined reference value.

1 . A method for producing fluorine gas, the fluorine gas being produced by electrolyzing an electrolyte containing hydrogen fluoride and a metal fluoride, the method comprising:
 electrolyzing the electrolyte in an electrolytic cell;   measuring a water concentration in the electrolyte in the electrolyzing; and   sending a fluid generated in an inside of the electrolytic cell in the electrolyzing the electrolyte, from the inside to an outside of the electrolytic cell through a flow path, wherein   in the sending, the flow path in which the fluid flows is switched in accordance with the water concentration in the electrolyte measured in the measuring a water concentration, such that the fluid is sent to a first flow path that sends the fluid from the inside of the electrolytic cell to a first outside when the water concentration in the electrolyte measured in the measuring a water concentration is not more than a predetermined reference value, or the fluid is sent to a second flow path that sends the fluid from the inside of the electrolytic cell to a second outside when the water concentration is more than the predetermined reference value, and   the predetermined reference value is a numerical value of 0.1% by mass or more and 0.8% by mass or less.   
     
     
         2 . The method for producing fluorine gas according to  claim 1 , wherein the metal fluoride is a fluoride of at least one metal selected from the group consisting of potassium, cesium, rubidium, and lithium. 
     
     
         3 . The method for producing fluorine gas according to  claim 1 , wherein an anode used in the electrolyzing is a carbonaceous electrode formed from at least one carbon material selected from the group consisting of diamond, diamond-like carbon, amorphous carbon, graphite, and glassy carbon. 
     
     
         4 . The method for producing fluorine gas according to  claim 1 , wherein the electrolytic cell has a structure in which bubbles generated on an anode or a cathode used in the electrolyzing are capable of rising vertically in the electrolyte to reach a surface of the electrolyte. 
     
     
         5 . A device for producing fluorine gas, the fluorine gas being produced by electrolysis of an electrolyte containing hydrogen fluoride and a metal fluoride, the device comprising:
 an electrolytic cell storing the electrolyte and configured to perform the electrolysis;   a water concentration measurement unit configured to measure a water concentration in the electrolyte in the electrolytic cell during the electrolysis; and   a flow path configured to send a fluid generated in an inside of the electrolytic cell during the electrolysis of the electrolyte, from the inside to an outside of the electrolytic cell, wherein   the flow path includes a first flow path configured to send the fluid from the inside of the electrolytic cell to a first outside and a second flow path configured to send the fluid from the inside of the electrolytic cell to a second outside and includes a flow path switching unit configured to switch the flow path in which the fluid flows, to the first flow path or the second flow path in accordance with the water concentration in the electrolyte measured by the water concentration measurement unit,   the flow path switching unit is configured to send the fluid from the inside of the electrolytic cell to the first flow path when the water concentration in the electrolyte measured by the water concentration measurement unit is not more than a predetermined reference value, or to send the fluid from the inside of the electrolytic cell to the second flow path when the water concentration is more than the predetermined reference value, and   the predetermined reference value is a numerical value of 0.1% by mass or more and 0.8% by mass or less.   
     
     
         6 . The method for producing fluorine gas according to  claim 2 , wherein an anode used in the electrolyzing is a carbonaceous electrode formed from at least one carbon material selected from the group consisting of diamond, diamond-like carbon, amorphous carbon, graphite, and glassy carbon. 
     
     
         7 . The method for producing fluorine gas according to  claim 2 , wherein the electrolytic cell has a structure in which bubbles generated on an anode or a cathode used in the electrolyzing are capable of rising vertically in the electrolyte to reach a surface of the electrolyte. 
     
     
         8 . The method for producing fluorine gas according to  claim 3 , wherein the electrolytic cell has a structure in which bubbles generated on the anode or a cathode used in the electrolyzing are capable of rising vertically in the electrolyte to reach a surface of the electrolyte.