本文采用曲线拟合法分光光度测定Pr、Sm混合物中的单一稀土。用CyDTA扩大Pr、Sm吸收光谱形状的差别。直接光度法求出Pr、Sm总量,并以此为浓度限定条件,使计算结果的准确度有所提高,计算时间大大缩短。不同比例的Pr、Sm混合物的测定误差大多在5%以内,方法简便、快速。 In this paper, curve fitting spectrophotometric determination of Pr, Sm mixture of a single rare earth. Use CyDTA to broaden the difference between Pr and Sm absorption spectrum shapes. The total amount of Pr and Sm was calculated by the direct photometric method, and the concentration was defined as the concentration so that the accuracy of the calculation result was improved and the calculation time was greatly shortened. Different proportions of Pr, Sm mixture measurement error mostly within 5%, the method is simple and fast.