Method for recovering valuable metal from waste electrode material of lithium secondary battery by using lithium carbonate

A method of recovering valuable metals by using a waste electrode material, the method comprising:

• a waste electrode material preparation step of preparing a waste electrode material;
• a pre-processing step of thermally processing the waste electrode material in a firing furnace in a temperature range of 300° C. to 500° C. for a duration of 30 minutes to 120 minutes;
• a sulfuric acid dissolution step of, after the pre-processing step, adding sulfuric acid to the waste electrode material so that the waste electrode material reacts with the sulfuric acid;
• a first solid-liquid separation step of separating the resulting product obtained through the sulfuric acid dissolution step into a metal melt and an unreacted residue;
• a precipitation step of mixing lithium carbonate (Li2CO3) with the metal melt and stirring the resulting mixture;
• and
• a second solid-liquid separation step of separating the resulting product obtained through the precipitation step into a precipitate and a filtrate,
• wherein an aqueous solution of lithium sulfate is recovered from the filtrate, and nickel carbonate and cobalt carbonate are recovered from the precipitate.