Abstract: Improved process for preparing sodium carbonate from crude trona without carbon column scaling by evaporating a portion of water from a clarified sodium carbonate solution to crystallize sodium carbonate crystals therefrom, separating the sodium carbonate crystals from the crystallizer liquor, passing only the crystallizer liquor which contains organic impurities through a carbon column to reduce the organic impurity concentration therein, and evaporating a portion of water from the carbon treated crystallizer liquor to crystallize additional sodium carbonate crystals.

Abstract: A method for enhancing recovery of sodium carbonate from sodium carbonate solutions which contain sodium chloride. Anhydrous sodium carbonate is recovered in good yields from aqueous sodium carbonate solutions containing sodium chloride by evaporative crystallization at superatmospheric pressure and at a temperature of at least about 120.degree. C.