Study On Technology And Phase Diagram Of Potassium Sulphate Prepared By Ammonium Sulphate Method In EG Solution

The process of the technology of potassium sulfate by potassium chloride and ammonium sulphate has advantages of little investment abundant raw materials and low production cost, as well as disadvantages of complex technology and low reaction conversion. Based on the fact that some organic solvents can change property of the water-ion system, the relation between organic solvents such as methanol etc. and yield of potassium oxide is studied, which indicates that ethylene glycol(EG) can be selected as the additive. The phase diagrams of the system K+ NH4+//SO42- Cl^- (CH2OH)2-H2O at 25℃ are determined, and the phase relations of the reaction system are simple common saturation and no compound is formed. The proper technology conditions of the production process are investigated by the single-factor and orthogonal experiments with the result of the reaction time of 80 min, reaction temperature of 25 ℃, ethylene glycol concentration of 40%, initial concentration of ammonium sulphate of 35%, feed ratio of KC1 and (NH₄)₂SO₄ of 1.9/1.0. The yield of potassium oxide under this condition is 92.24%, the quality of potassium sulphate can come up to the first rank standard of agricultural potassium sulphate. The new technology of potassium sulphate by potassium chloride and ammonium sulphate with the existing condition of ethylene glycol is discussed, and it has simple technology, high yield of potassium oxide and superior quality of production compared with that of synthesized in distilled water.