Extraction and purification of 227Ac and development of solid 219Rn source

The method of 227Ac extraction and purification from high-grade uranium ore and the test results of solid 219Rn source made from 227Ac are reported in this paper. With five years of follow-up monitoring, radiochemical purity of 227Ac and the emanation power of solid 219Rn source has been checked by emanation method and γ-spectrometry, the results showed that 228Th, 231Pa and 226Ra have been effectively removed and the emanation power of 219Rn source is about 80%. The long-term test results also showed that the 219Rn emanation rate remains stable in a wide air humidity range (40% ∝ 90%). Though the 219Rn source has not been accurately calibrated yet, it has been applied in the research for delay coincidence measurement of 223Ra. (orig.)