A process for the formation of ammonium sulfate by changing decomposition of calcium sulfate and ammonium carbonate

摘要

310,635. Slade, R. E., and Imperial Chemical Industries, Ltd. April 11, 1928. Ammonium sulphate.-In preparing ammonium sulphate by the interaction of calcium sulphate and ammonium carbonate, the contamination of the ammonium sulphate crystals by iron is reduced by returning a portion of the mother liquor to a previous stage of the process where the mixture is still alkaline, in order to precipitate iron. The liquor may be added to the mixture before or after the separation of calcium carbonate, and the precipitated iron removed by filtration or settling.