Rapid analysis of uranium in the reprocessing operations of thoria irradiated in power reactors using extractant Alamine®336

Similar to analytical method, developed by Moore and Hudgens for the estimation of Pu in PUREX operations, an analytical technique is essential to monitor U for its recovery and losses in the plant operations of thoria reprocessing. Analysis of U in the samples containing significant proportion of ²³²U and high concentration of Th is of great concern. Transmutation of Th in the nuclear power reactor produces notable quantity of ²³²U (half life 68.9 years) along with fissile isotope ²³³U. The decay series of ²³²U is initiated with ²²⁸Th (half life 1.9 year) and this is followed by several short lived á emitting progenies, ²²⁴Ra, ²²⁰Rn, ²¹⁶Po, ²¹²Bi, and ²¹²Po. Due to high specific activity, ²²⁸Th, with its smallest contamination in the sample gives high count rate in the assay of the solution which is intended for the radiometric determination of U. For obtaining highly selective separation of U which can be amenable for its quantification using highly sensitive radiometric method, its liquid - liquid extraction (LLE) is studied using Alamine®336 in the organic phase. Experimental conditions of LLE are optimized for maximum decontamination and recovery of U. The effect of different interfering ionic impurities in the sample on the process of separation is investigated. Depending on the level of the concentration of U in the samples, spectrophotometry or radiometry methods are adopted for its determination