US Patent 9994931 Method for extracting lithium from solution containing lithium

Disclosed is a method of extracting lithium from a solution including lithium. The method of extracting lithium from a solution including lithium includes: separating the solution including lithium into a monovalent ion-containing solution and a solution including ions having more than divalence using a separation membrane having a negative charge on its surface; removing impurities from the monovalent ion-containing solution; and precipitating lithium dissolved in the monovalent ion-containing solution into lithium phosphate by adding a phosphorus-supplying material to the monovalent ion-containing solution.