Patent ID: 6190636
Filing Date: 2001-02-20
Classification: C01B,C01D,C01F

Abstract:
A method of recycling by-products from industrial processes comprising:reacting an alkali-metal sulfate with an alkaline earth metal chloride to produce an alkaline earth metal sulfate precipitate and alkali metal chloride solution;separating the alkaline earth metal sulfate precipitate from the alkali metal chloride solution;combining the alkaline earth metal sulfate precipitate with a reagent selected from the group consisting of ammonia/carbon dioxide mixtures, ammonium carbonate, and ammonium bicarbonate to produce ammonium sulfate and an alkaline earth carbonate precipitate;separating the alkaline earth carbonate precipitate from the ammonium sulfate; andmixing chlorine with the ammonium sulfate, ammonium bisulfate, or mixtures thereof to produce sulfuric acid, hydrochloric acid and nitrogen.