复分解法生产磷酸二氢钾的新工艺

New techniques of the preparation of potassium dihydrogen phosphate by double decomposition method

研究了以液氨、氯化钾和湿法磷酸为原料,通过复分解法生产磷酸二氢钾的工艺,确定复分解反应的最佳反应条件为:氨与磷酸物质的量比为1.05:1,氯化钾与磷酸物质的量比为1.1:1,反应时间为50 min,反应温度为70～80℃,所得磷酸二氢钾达到HG2321-1992质量标准,可作为农业高效复合肥料.该工艺简单,能耗和原料消耗低,原料综合利用率高,生产过程无三废产生.

Using liquid ammonia, potassium chloride and phosphoric acid by wet process as raw materials, the method of the preparation of potassium dihydrogen phosphate （ KH2PO4 ） by double decomposition process is studied. The optimal technological conditions are as follows ： n（ NH3 ） ：n（ H3PO4 ） = 1.05 ： 1 and n（ KCl） ：n（ H3PO4 ） = 1.1 ： 1 ,the double decomposition reaction time is 50 min and reaction temperature is 70 - 80 ℃, the quality of KH2 P04 can reach the standard of HG2321-92. It can be used as high effect complex fertilizer in agriculture. This crafts is simple, the energy and raw material consumption are low , the comprehensive using rate of raw material is high, and no wastes are occurred during operation.