分光光度计的改装及在锑测定中的应用

Modification of spectrophotometer and its application in determination of antimony

试样以硫酸分解,在硫酸(1+4)中加入碘化钾,Sb3+与碘化钾形成[SbI4]-黄色络合物,在改装后分光光度计上测量吸光度,建立快速测定锑的方法。Sb3+质量在0~250μg范围内符合朗伯比尔定律,回归方程为y=0.945 6 x+0.002 3,线性相关系数r=0.999 7。方法适用于样品中1.00%以下锑的测定。按照实验方法测定地质样等不同样品中锑,结果的相对标准偏差(RSD,n=6)为2.1%~6.8%。并与国标法GB/T 15925-2010及改进前分光光度计和目视比色法的测定结果相吻合。

The sample was decomposed with sulfuric acid.After adding potassium iodide into sulfuric acid(1+4),Sb3+would react with potassium iodide to form yellow [SbI4]-complex.The absorbance was measured on a modified spectrophotometer,and the rapid determination method of antimony was established.Beer's law was obeyed for Sb3+in range of 0-250μg.The regression equation was y=0.945 6 x+0.002 3with correlation coefficient of r=0.999 7.The proposed method was applicable for the determination of antimony in sample with content lower than 1.00%.The content of antimony in different geological samples was determined according to the experimental method.The relative standard deviations(RSD,n=6)were between 2.1% and 6.8%.The found results were consistent with those obtained by national standard method(GB/T 15925-2010)as well as unmodified spectrophotometer and visual colorimetry.