Extraction apparatus, extraction method, and method of manufacturing lithium hydroxide

Abstract

An extraction apparatus is provided and includes a first aqueous medium, a second aqueous medium, a first electrode, a second electrode, and a first electric power source. The first aqueous medium includes two or more kinds of metal ions. The second aqueous medium is separated from the first aqueous medium. The first electrode is immersible in the first aqueous medium in a state of not being immersed in the second aqueous medium, and is immersible in the second aqueous medium in a state of not being immersed in the first aqueous medium. The second electrode is immersible in the first aqueous medium. The first electric power source is coupled to the first electrode and the second electrode. The two or more kinds of metal ions include a lithium ion. The first electrode includes a titanium oxide. The first electric power source is configured to energize the first electrode and the second electrode in a state where the first electrode and the second electrode are immersed in the first aqueous medium. The first electrode that has been energized in a state of being immersed in the first aqueous medium is immersible in the second aqueous medium.

1 . An extraction apparatus comprising:
 a first aqueous medium including two or more kinds of metal ions;   a second aqueous medium separated from the first aqueous medium;   a first electrode that is immersible in the first aqueous medium in a state of not being immersed in the second aqueous medium, and is immersible in the second aqueous medium in a state of not being immersed in the first aqueous medium;   a second electrode that is immersible in the first aqueous medium; and   a first electric power source coupled to the first electrode and the second electrode, wherein   the two or more kinds of metal ions include a lithium ion,   the first electrode includes a titanium oxide,   the first electric power source is configured to energize the first electrode and the second electrode in a state where the first electrode and the second electrode are immersed in the first aqueous medium, and   the first electrode that has been energized in a state of being immersed in the first aqueous medium is immersible in the second aqueous medium.   
     
     
         2 . The extraction apparatus according to  claim 1 , wherein the titanium oxide selectively captures the lithium ion out of the two or more kinds of metal ions, and releases the lithium ion. 
     
     
         3 . The extraction apparatus according to  claim 1 , wherein the first aqueous medium has a pH of higher than 10. 
     
     
         4 . The extraction apparatus according to  claim 1 , wherein the titanium oxide includes anatase-type titanium dioxide, lithium titanate (Li 4 Ti 5 O 12 ), or both. 
     
     
         5 . The extraction apparatus according to  claim 1 , wherein
 the first electrode includes electrode particles,   the electrode particles each include the titanium oxide, and   the first electrode includes a porous structure in which the electrode particles are directly joined to each other.   
     
     
         6 . The extraction apparatus according to  claim 5 , wherein the electrode particles have an average particle size of 100 nanometers or smaller. 
     
     
         7 . The extraction apparatus according to  claim 6 , wherein the average particle size is 30 nanometers or smaller. 
     
     
         8 . The extraction apparatus according to  claim 5 , wherein
 the first electrode includes an electrode layer having the porous structure,   the electrode layer has a volume density of greater than or equal to 1.0 grams per cubic centimeter and less than or equal to 3.5 grams per cubic centimeter, and   the electrode layer has a specific surface area of greater than or equal to 1 square meter per gram and less than or equal to 500 square meters per gram.   
     
     
         9 . The extraction apparatus according to  claim 1 , wherein
 the second aqueous medium includes an aqueous lithium hydroxide solution, and   the aqueous lithium hydroxide solution has a concentration of 1 mole per cubic decimeter or lower.   
     
     
         10 . The extraction apparatus according to  claim 1 , further comprising:
 a third electrode that is immersible in the second aqueous medium; and   a second electric power source coupled to the first electrode and the third electrode, wherein   the second electric power source is configured to energize the first electrode and the third electrode in a state where the first electrode and the third electrode are immersed in the second aqueous medium.   
     
     
         11 . The extraction apparatus according to  claim 10 , wherein the third electrode includes at least one of titanium, platinum, iridium, nickel, iron, or palladium as a constituent element. 
     
     
         12 . The extraction apparatus according to  claim 1 , further comprising a moving mechanism configured to move the first electrode between the first aqueous medium and the second aqueous medium. 
     
     
         13 . The extraction apparatus according to  claim 1 , further comprising:
 a first container member that contains the first aqueous medium; and   a first supplying mechanism configured to supply the first aqueous medium to the first container member.   
     
     
         14 . The extraction apparatus according to  claim 1 , further comprising:
 a second container member that contains the second aqueous medium; and   a second supplying mechanism configured to supply the second aqueous medium to the second container member.   
     
     
         15 . An extraction method comprising:
 immersing a first electrode and a second electrode in a first aqueous medium, the first electrode including a titanium oxide, the first aqueous medium including two or more kinds of metal ions including a lithium ion;   energizing the first electrode and the second electrode in a state where the first electrode and the second electrode are immersed in the first aqueous medium; and   immersing, in a second aqueous medium, the first electrode that has been energized in a state of being immersed in the first aqueous medium, the second aqueous medium being separated from the first aqueous medium.   
     
     
         16 . The extraction method according to  claim 15 , further comprising:
 additionally immersing a third electrode in the second aqueous medium; and   generating hydrogen at the third electrode by energizing the first electrode and the third electrode in a state where the first electrode and the third electrode are immersed in the second aqueous medium.   
     
     
         17 . A method of manufacturing lithium hydroxide, the method comprising:
 immersing a first electrode and a second electrode in a first aqueous medium, the first electrode including a titanium oxide, the first aqueous medium including two or more kinds of metal ions including a lithium ion;   energizing the first electrode and the second electrode in a state where the first electrode and the second electrode are immersed in the first aqueous medium;   immersing, in a second aqueous medium, the first electrode that has been energized in a state of being immersed in the first aqueous medium and a third electrode, the second aqueous medium including pure water or an aqueous lithium hydroxide solution and being separated from the first aqueous medium; and   generating hydrogen at the third electrode by energizing the first electrode and the third electrode in a state where the first electrode and the third electrode are immersed in the second aqueous medium.