Authors: Kalaya Changkrueng, Saowaluck Thong-in and Harinate Mungpayaban
Publication Type: The 42nd Congress on Science and Technology of Thailand
Year: 2017
Abstract: Uranium isotope and thorium were separated in nitric acid form by using ion exchange column-resin. This experiment was tested in batch. Feed was prepared from uranium, thorium and rare earth elements (REE) in 80 ppb concentrations. Three types of Dowex-50 cation exchange resins (x2, x4 and x8) were used in this experiment for uranium isotope and thorium separation. Three nitric acid concentrations (1 M, 2 M, and 3 M) were used to elute uranium isotope, while thorium was eluted by 6 M, 7 M, and 8 M of Nitric acid. The results are shown that 1 M HNO3 and 7 M HNO3 were appropriate condition for uranium and thorium separation respectively. In this study, the optimum extraction resin of uranium was x4 Dowex-50 and thorium in rare earth mixture was x2 Dowex-50. Uranium isotopes, thorium and other REE concentration were determined by inductively coupled plasma – mass spectrometry (ICP-MS). Furthermore, this work used to study problem of matrix effects of high counting signal from each elements which could be interfered with the signal of low concentration elements in sample mixture.