诱导动力学光度法测定微量铀

依据铀(Ⅳ)对Cr_2O_7~(2-)-I~--淀粉氧化还原反应体系的诱导作用,提出了一种测定微量铀的动力学新方法,并研究了测定的最佳条件。在U(Ⅳ)为0—1.78μg·ml~(-1)范围内,诱导与非诱导体系在波长600nm处的吸光度之差与铀含量成正比,方法检测限为0.024μg·ml~(-1)。本法对铀(Ⅳ)具有很好的选择性,绝大多数易与铀共存的稀有金属均不影响测定。本法用于矿石中铀的测定可得到满意的结果。

DETERMINATION OF TRACE URANIUM BY KINETIC SPECTROPHOTOMETRY

A novel kinetic spectrophotometric method for the determination of trace uranium was proposed based on the inductive effect of uranium (IV ) on redox systems of Cr( VI )-I-starch,and the optimal conditions of determination were established. The calibration curve is linear for U( IV ) over the concentration range of 0-1. 78ug ml-1 ,and the detection limit is 0. 024ug ml-1. The procedure is selective for U(IV) ,and the interference of most rare metal cations coexisting with uranium are negligible. The method was used to determine the uranium in an iron ore,and the results were satisfactory.