Method for dissolving lithium compound, method for manufacturing lithium carbonate, and method for recovering lithium from lithium ion secondary cell scrap
A method for dissolving a lithium compound according to the present invention includes bringing a lithium compound into contact with water or an acidic solution, and feeding, separately from the lithium compound, a carbonate ion to the water or the acidic solution to produce carbonic acid, and allowing the carbonic acid to react with the lithium compound to produce lithium hydrogen carbonate.
1. A method for dissolving a lithium compound, the method, comprising bringing a lithium compound into contact with water or an acidic solution, and feeding, separately from the lithium compound, a carbonate ion to the water or the acidic solution to obtain a lithium dissolved solution,
wherein the lithium compound comprises cobalt, aluminum, and at least one of lithium hydroxide, lithium oxide, and lithium carbonate, and
wherein a pH of the lithium dissolved solution is from 7 to 10.
2. The method for dissolving the lithium compound according to claim 1 , wherein the carbonate ion is fed so as to maintain a saturated state of carbonic acid in the water or the acidic solution.
3. The method for dissolving the lithium compound according to claim 1 , wherein the feeding of the carbonate ion is carried out by blowing a carbon dioxide gas into the water or the acidic solution.
4. The method for dissolving the lithium compound according to claim 1 further comprising separating lithium from the lithium dissolved solution, and precipitating a lithium ion in the lithium dissolved solution as lithium carbonate.
5. The method for dissolving the lithium compound according to claim 4 , wherein when the lithium ion is precipitated, the lithium dissolved solution is heated to separate carbonic acid as a carbon dioxide gas from the lithium dissolved solution.
6. The method for dissolving the lithium compound according to claim 5 , wherein when the lithium ion is precipitated, the lithium dissolved solution is heated at a temperature of from 50° C. to 90° C.
7. The method for dissolving the lithium compound according to claim 1 , wherein when the lithium compound is brought into contact with the water or the acidic solution, the water or the acidic solution has a temperature of from 5° C. to 25° C.