METHOD FOR DETERMINING QUANTITY OF LOW-CONCENTRATION IODINE IN NITRATE SOLUTION, ESPECIALLY IN URANYL NITRATE SOLUTION

摘要

PURPOSE: To provide a method of quantifying low concentration iodine in a nitrate solution, particularly, uranyl nitrate solution. CONSTITUTION: In this method, a reducing agent such as ascorbic acid is added to a sample to be quantified in order to keep the iodine in an iodide state. The potential difference E1 between an iodide ion selecting electrode 5 and a reference electrode 7 is measured, and first and second iodide solutions having a known iodide concentration and containing a reducing agent are continuously added. After each addition, the potential differences E2, E3 between the electrodes 5 and 7 are measured, and the initial iodine concentration of the solution is calculated from E1, E2, E3 and the concentration and volume in addition.