X射线荧光光谱法测定复混肥料中氯、磷、钾的含量

分别称取15个校准样品约5.0g,加入40g·L^-1 EDTA溶液60mL,在80℃的水浴中振荡1.5h,冷却后用水定容至100.0mL,过滤得到澄清的溶液用作校准溶液,按照相同的步骤制备空白溶液和样品溶液。选用厚度为8μm的聚乙烯薄膜作为存储溶液的界面材料,测试溶液层厚度为8mm。在选定的仪器条件下,采用手持式能量色散型-X射线荧光光谱仪测定试液中的氯、磷和钾。Cl^-、P2O5和K2O的质量浓度在一定范围内与对应的荧光强度呈线性关系,检出限(3s)分别为0.020,0.036,0.032g·L^-1。采用本方法测定复混肥中氯、磷、钾的含量,测得结果与国家标准方法的结果一致,精密度高于国家标准方法。

Determination of Cl,P and K in Compound Fertilizer by X-Ray Fluorescence Spectroscopy

About 5.0 g of the 15 calibration samples were taken and to each sample 60 mL of 40 g·L^-1 EDTA solution were added.The mixtures were shaken in a water bath at 80 ℃ for 1.5 h.After cooling,the solutions were made up to 100.0 mL with water,and filtered to obtain clear solutions for use to prepare the calibration curves.Blank solution and sample solution were prepared in the same way.Polyethylene film with a thickness of 8μm was selected as the interface material for storage of the sample solution,and the thickness of the test solution layer was 8 mm.Cl,P and K in the test solution were determined by a hand-held energy dispersive Xray fluorescence spectrometer under optimized instrument conditions.Linear relationships were found between fluorescence intensity and corresponding mass concentration of Cl^-,P2O5 and K2O within definite ranges,and the detection limits(3 s)were 0.020,0.036,0.032 g·L^-1,respectively.The method was used to determine the content of Cl,P and K in 2 compound fertilizer samples,giving results in consistency with those obtained by national standard method,and the precision of the method higher than that of national standard method.