Composition and properties were studied of products formed in treatment of solid Na2CO3 with aqueous solutions containing acetic and citric acids with mass fractions of 0.40-0.60 and 0.33-0.49, respectively, at a Na2CO3/H (x) An molar ratio of 2-6, where H (x) An = CH3COOH and H-3(C6H5O7). It was found that the content of water in the systems under study and the strength of an acid affect the yield of the double salt of carbonic acid, Na2CO3 center dot NaHCO3 center dot 2H(2)O and the composition of derivative proton-containing compounds. It is noted that sodium sesquicarbonate can be formed both by the crystallization mechanism and via a transformation of the primary structure of sodium carbonate. In the resulting powder-like products, water introduced with the acid solution is predominantly consumed for formation of crystal hydrates of carbonate-containing and derivative proton-containing compounds. The hygroscopic point of the resulting salt formulations was determined to be at a level of 70-75. It was noted that sesquicarbonate-containing salt formulation formed in "dry" neutralization of sodium carbonate by acid solutions can be regarded as a builder for obtaining synthetic household detergents.
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