Patent ID: 8287829

Claim:
A method of producing high purity lithium carbonate, comprising the steps of: reacting a first aqueous solution comprising a technical grade Li 2 CO 3 with CO 2 to form a second aqueous solution comprising dissolved LiHCO 3 ; separating unreacted CO 2 and insoluble compounds from the second aqueous solution using a gas-liquid-solid separator to produce a third aqueous solution, supplying the third aqueous solution to a reverse osmosis apparatus to concentrate the Li 2 CO 3 , wherein the reverse osmosis apparatus is operable to remove CO2 from the solution; removing dissolved impurities from the third aqueous solution by contacting the third aqueous solution with an ion selective medium to produce a fourth aqueous solution; and precipitating Li 2 CO 3 from the fourth aqueous solution, wherein the Li 2 CO 3 has a purity of at least about 99.99%.