Abstract: Take the filtered leaching-liquid of the sinter of the potassium-rich rocks from Luonan,Shaanxi as the object of the study.By inlet CO₂ gas,ammonia and sec-butanol were added into the liquid,then NaHCO₃ and KHCO₃ were separated under the action of salting out to produce the agricultural potassium sulphate.Technology of separating Na-K mixed solution by ammonia-alcohol salting out method was studied.Experiment results indicated that the mass fraction of separated KHCO₃ was up to 95.29% under the optimum process conditions.Sulfuric acid was added to the solution of KHCO₃ to prepare potassium sulphate.Prepared K₂SO₄ reached the first-rate of National Agriculture Potassium Sulphate Standard.

Key words: ammonia, alcohol, sodium bicarbonate, potassium bicarbonate, potassium sulphate