摘要 |
<p>A process for the preparation of potassium sulfate, sodium bicarbonate and sodium carbonate. The process involves the treatment of potash brines by the reaction of sodium chloride and potassium chloride with calcium sulfate and sodium sulfate. Syngenite precipitate is produced and a first filtrate containing sodium chloride and potassium chloride. The syngenite precipitate is treated with ammonia or ammonium ions and carbon dioxide at between 70 °C and 100 °C, with the result being calcium carbonate precipitate and a second filtrate containing ammonium sulfate and potassium sulfate. The second filtrate is cooled to a temperature of between 20 °C and 40 °C and treated with potassium chloride. A potassium sulfate precipitate results. The sodium bicarbonate is precipitated from the first filtrate.</p> |