Electrodialytic process for the conversion of impure soda values to sodium hydroxide and carbon dioxide

A process for the production of high strength, high purity NaOH and CO.sub.2 from soda values in an electrodialysis cell having an anode and a cathode compartment separated by base and acid zones, which comprises the steps of:

• (a) introducing an aqueous soda solution having NaHCO.sub.3, Na.sub.2 CO.sub.3, trona or mixtures thereof to an acid zone of the electrodialysis cell located between a cation permselective face of a bipolar membrane and one face of a cation permselective membrane;
• (b) introducing an aqueous NaOH solution to a base zone of the cell located between an anion permselective face of a bipolar membrane and the other face of said cation permselective membrane;
• (c) passing direct electric current through the electrodialysis cell thereby producing H.sub.2 CO.sub.3 and CO.sub.2 gas from the soda solution in the acid zone and producing a NaOH-enriched stream in the base zone;
• (d) withdrawing the NaOH-enriched product stream from the base zone;
• and
• (e) withdrawing H.sub.2 CO.sub.3 and CO.sub.2 gas and partially depleted soda solution from the acid zone.