熔融法制样-X射线荧光光谱法测定煤灰中主次成分的含量

Determination of Major and Minor Components in Coal Ash by X-Ray Fluorescence Spectrometry Combined with Melting Method for Sample Prepartion

在铂金坩埚中依次加入4.000 0g无水四硼酸锂,0.250 0g试样,0.250 0g钴内标试剂,搅拌均匀,再用3.000 0g无水四硼酸锂覆盖在表面,加入1 000g·L-1溴化锂溶液0.25mL后,在电加热自动熔样机中于650℃预氧化10min后,在1 080℃前置2min,熔融17min,后置3min制得熔片,在所选仪器工作条件下测定煤灰中主次成分的含量。选用12份经国家标准方法定值的煤灰样品和两份铁矿石标准样品作为校准样品绘制标准曲线,采用经验系数法和理论α系数法对曲线进行基体校正和谱线重叠干扰校正。采用试验方法对煤灰样品中各组分进行测定,所得结果和标准方法测得值一致,测定值的相对标准偏差(n=11)在0.23%~5.3%之间。

4.000 0 g of anhydrous lithium tetraborate,0.250 0 g of the sample,and 0.250 0 g of Co internal standard were added into a platinum crucible successively.The mixture was stirred well,and then covered with3.000 0 g of anhydrous lithium tetraborate on the surface.After 0.25 mL of 1 000 g·L-1 lithium bromide solution was added,the mixture was pre-oxidized at 650℃for 10 min in an electric heating auto-melting sampler,and then placed at 1 080℃for 2 min,melted for 17 min,and set for 3 min to obtain a fuse,for determination of major and minor components in the coal ash sample under selected working conditions.Twelve tandard coal ash samples determined by national stanard method and two iron ore standard samples were used as the calibration samples to draw the calibration curves.The matrix correction and spectral line overlap interference correction were performed by using the empirical coefficient method and theoreticalαcoefficient method.The components of the coal ash samples were determined by the proposed method,giving results were consistent with that obtained by the standard method,and RSDs（n=11）in the range of 0.23%-5.3%.