Sodium Carbonate → Sodium Sesquicarbonate

Participants

Reaction Steps

This Example describes an alternate embodiment of the present invention illustrated in FIG. 7 utilizing two-compartment water splitting to generate sodium carbonate and sodium hydroxide from trona ore. To a dissolver 710 equipped with a stirrer 711, is added trona ore via a line 712 and live steam via a line 714 to form a slurry of sodium carbonate/sodium bicarbonate and insolubles which is removed from the dissolver 710 via a line 716 and forwarded to a liquor purification tank 718. An aqueous sodium carbonate/sodium bicarbonate solution is removed from the tank 718 via a line 720 and forwarded to a crystallizer 722. Sodium bicarbonate solid, formed in the crystallizer 722, is removed via a line 726 and is fed to a centrifuge 727. The remaining aqueous solution of sodium carbonate and bicarbonate (mother liquor) is removed from the crystallizer 722 via a line 742a. In a secondary crystallizer 728, a more concentrated sodium carbonate solid and/or slurry is formed and removed via a line 730 to acid tank 732. An aqueous solution of sulfuric acid/sodium sulfate is added, via a line 740, to the tank 732. The source of sulfuric acid/sodium sulfate is the reaction product from the acid compartments A of the two-compartment electrodialytic water splitters 752 and 754 which is withdrawn via lines 740a and 740b, respectively. The composition of the source comprises about 1 to 15 weight % of sulfuric acid and about 10 to 30 weight % of sodium sulfate. In the acid tank 732 sodium bicarbonate reacts with sulfuric acid (from the source and also supplied via a line 736) to form sodium sulfate and carbon dioxide (which is removed via a line 734). The sodium sulfate produced in the acid tank 732 is removed via a line 738 for supply (via lines 738a and 738b) to the acid compartments of the two-compartment water splitters.

Provenance & Evidence