微波加热合成聚磷酸铵的工艺研究

Study on process of synthesizing ammonium polyphosphate by microwave heating

以磷酸二氢铵和尿素为原料,采用微波加热研究聚磷酸铵的最优聚合工艺条件。分别考察不同原料配比、反应温度和反应时间对聚磷酸铵中五氧化二磷含量、氮含量和聚合度的影响。通过实验得出微波加热聚合聚磷酸铵的最优条件为:磷酸二氢铵与尿素物质的量比为1∶1.1、反应温度为170℃、反应时间为20 min,样品经XRD检测为Ⅰ-型聚磷酸铵,该条件下得到的产品五氧化二磷质量分数为70.33%、氮质量分数为14.34%、聚合度为50.33,符合化工行业标准HG/T 2770—2008一等品指标要求。

The optimal polymerization conditions of ammonium polyphosphate were studied by microwave heating using ammonium dihydrogen phosphate and urea as raw materials.The effects of different ratios of raw materials,reaction temperature and reaction time on the contents of phosphorus pentoxide and nitrogen content and polymerization degree in ammonium polyphosphate were studied.The optimum conditions for the microwave heating of ammonium polyphosphate were as follows:the amount-of-substance ratio of ammonium dihydrogen phosphate to urea was 1∶1.1,the reaction temperature was 170 ℃ and the reaction time was 20 min.The sample was I-type polyphosphate detected by XRD.Under the optimal conditions,the yield of prepared phosphorus pentoxide was 70.33%,the mass fraction of nitrogen was 14.34% and the polymerization degree was50.33.This index met the first grade of chemical industry standard HG/T 2770—2008.