Processes and systems for preparing lithium carbonate

A process for preparing lithium carbonate, said process comprising:

• submitting an aqueous composition comprising lithium sulphate to an electrolysis or an electrodialysis under conditions suitable for converting at least a portion of said lithium sulphate into lithium hydroxide, wherein during said electrolysis or said electrodialysis, said aqueous composition comprising lithium sulphate is at least substantially maintained at a pH having a value of about 1 to about 4;
• and
• converting said lithium hydroxide into lithium carbonate,
• wherein converting said lithium hydroxide into lithium carbonate is carried out by:
• reacting an aqueous composition comprising said lithium hydroxide with CO2 by sparging said CO2 into said composition, said sparging being carried out while pH is at least substantially maintained at a value of about 10 to about 12.5, thereby obtaining a slurry comprising said lithium carbonate;
• inserting at least a portion of said slurry into a clarifier and obtaining a supernatant comprising lithium bicarbonate and a solid comprising said lithium carbonate;
• separating said solid from said supernatant;
• and
• heating said supernatant at a temperature of at least about 85° C. so as to at least partially convert said lithium bicarbonate into lithium carbonate.