Accurate fast method with high chemical yield for determination of uranium isotopes (234U, 235U, 238U) in granitic samples using alpha spectroscopy

The present study aims to use the alpha-spectroscopy at Nuclear Materials Authority (NMA) of Egypt. A radiochemical technique for analysis uranium isotopes was carried out for ten mineralized granitic samples together with the International standards RGU-1 (IAEA) and St(4) (NMA). Several steps of sample preparation, radiochemical separation and source preparation were performed before analysis. Uranium was separated from sample matrix with 0.2 M TOPO in cyclohexane as an extracting agent with a chemical yield 98.95% then uranium was purified from lanthanides and actinides present with 0.2 M TOA in xylene as an extracting agent. The pure fraction was electrodeposited on a mirror-polished copper disc from buffer solution (NaHSO4+H2SO4+NH4OH ). Rectangle pt-electrode with an anode-cathode distance of 2 cm was used Current was 900 mA and the electrodeposition time reach up to 120 min. The achieved results show that the chemical yield ranged between 87.9 +/- 6.8 and 98 +/- 8.6. (C) 2015 Elsevier B.V. All rights reserved