Development of a pH titration method for the simultaneous determination of uranium, nitrate and free-acid in the feed solution of the sol-gel process of nuclear fuel fabrication

pH titration curves generated by slow addition of alkali to solutions containing varying concentrations of uranyl nitrate and nitric acid were studied using an autotitrator linked to a personal computer. A procedure with multiple choice of equations has been developed for the estimation of free acid, nitrate and uranium in pure uranyl nitrate solution by a single titration. The technique provides a simple single-step method with required accuracy and precision for the simultaneous estimation of the three quantities in the uranyl nitrate feed solution of the sol-gel process for making UO3 microspheres. The relative standard deviations in the determination of uranium and nitrate were ±0.82% and ±1.52%, respectively, in 15 determinations. (author)