通氨提纯氯化铵转化法制取硫酸钾新工艺研究

介绍了通氨盐析硫酸铵钾提纯氯化铵转化法制取硫酸钾的新工艺。精制硫酸钾母液Ⅱ和粗品氯化铵母液Ⅳ混合加热，与氯化钾和热析硫酸铵钾一起反应制取粗品硫酸钾，再与氯化钾反应得到含51.27%氧化钾的硫酸钾；分离粗硫酸钾后的母液Ⅰ与硫酸铵和通氨盐析硫酸铵钾一起高温反应，分离热析硫酸铵钾的母液，经蒸发一定水后，冷却制取粗氯化铵；由贫氨母液溶解粗氯化铵后，经通氨盐析硫酸铵钾分离的母液进行蒸氨后冷却析出含33.35%铵根、64.01%氯离子、0.5%氧化钾的氯化铵。整个工艺过程闭路循环，氧化钾回收率达96.5%~97.5%。

A new process for producing potassium sulfate by conversion method of ammonium chloride purified by inducing ammonia

A new process for producing potassium sulfate by conversion method of ammonium chloride purified by inducing ammonia was introduced.Refined potassium sulfate mother liquor Ⅱ and crude ammonium chloride mother liquor Ⅳ were mixed and heated. The mixture was reacted with potassium chloride and thermal precipitation potassium ammonium sulfate to produce crude potassium sulfate，and then reacted with potassium chloride to obtain potassium sulfate containing K2O of 51.27%（mass fraction）.After separating crude potassium sulfate，mother liquor Ⅰ reacted with ammonium sulfate and potassium ammonium sulfate through ammonia salting out under the high temperature condition.The mother liquor of thermal precipita tion of potassium ammonium sulfate was separated from the mother liquor.After evaporating a certain amount of water，it was cooled to produce crude ammonium chloride.After dissolving the crude ammonium chloride by the ammonia depleted mother liquor，the mother liquor from salting out potassium ammonium sulfate by inducing ammonia was subjected to steaming ammonia，and then the ammonium chloride containing NH4+ of 33.35%，Cl- of 64.01% and K2O of 0.5% was cooled and precipitated.The recovery rate of potassium oxide can reach 96.5%~97.5% in the closed circuit cycle of the whole process.