高聚合率的水溶性聚磷酸铵制备工艺研究

以湿法磷酸和尿素为原料制备高聚合率的水溶性聚磷酸铵,考察了尿素与磷酸的物质的量比、聚合温度和聚合时间对聚磷酸铵聚合率的影响。通过实验得到最优工艺条件:尿素与磷酸的物质的量比为1.4、聚合温度为180℃、聚合时间为1.0 h,所得产品的聚合率为98.20%,五氧化二磷质量分数为63.33%,氮质量分数为13.85%。该产品水溶性良好,通过XRD分析确定聚磷酸铵的晶型为Ⅰ型聚磷酸铵。

Research on preparation process of water-soluble ammonium polyphosphate with high polymerization rate

The water-soluble ammonium polyphosphate with high polymerization rate was prepared by using wet process phos-phoric acid and urea as raw materials.The effects of amount-of-substance ratio of urea to phosphoric acid,polymerization tem-perature and polymerization time on the polymerization rate of ammonium polyphosphate were investigated.The optimum pro-cess conditions were as follows：the amount-of-substance ratio of urea to phosphoric acid was 1.4,the polymerization temper-ature was 180 ℃ and the polymerization time was 1.0 h.Under the optimal conditions,the polymerization rate of the obtained product was 98.20%,the mass fraction of phosphorus pentoxide was 63.33% and the mass fraction of nitrogen was 13.85%. the water solubility was good,and the crystal form of ammonium polyphosphate was analyzed by XRD as type Ⅰ ammonium polyphosphate.