离子色谱法等度淋洗测定聚磷酸铵聚合率

Determination of Polymerization Rate of Ammonium Polyphosphate by Ion Chromatography with Equal Degree Elution

聚合率是衡量聚磷酸铵产品质量的重要指标,根据HG/T 5939-2021标准方法,利用离子色谱法梯度淋洗检测聚磷酸铵中正磷酸盐的含量,从而间接计算出聚合率。实验中根据万通离子色谱930型特性,利用梯度淋洗和等度淋洗进行方法摸索,梯度淋洗容易受压力波动、流动相比例、试剂纯度影响,使基线漂移大。而等度淋洗对仪器试剂要求不高,分析条件稳定单一、简单易于操作,测定样品相对标准偏差为0.5%~1.2%、加标回收率为99.7%~101.1%,满足分析检验要求。

The polymerization rate is an important indicator for measuring the quality of ammonium polyphosphate products.According to HG/T 5939-2021,the ion chromatography gradient elution method is used to detect the content of orthophosphate in ammonium polyphosphate,thereby indirectly calculating the polymerization rate.In the experiment,based on the characteristics of the 930 type of Wantong ion chromatography,gradient elution and isocratic elution were used to explore the methods.Gradient elution is easily affected by pressure fluctuations,mobile phase ratio,and reagent purity,resulting in significant baseline drift.However,isocratic elution does not require high requirements for instrument reagents,and the analytical conditions are stable,simple,and easy to operate.The relative standard deviation of the measured sample is 0.5%to 1.2%,and the recovery rate of the added standard is 99.7%to 101.1%,which meets the requirements of analysis and inspection.