Published 1987 | Version v1
Miscellaneous Open

Determination of rare earth elements, hafnium and cadmium in sintered pellets of mixed thorium and uranium oxides by neutron activation

Description

This work shows the development of a method for determination of the rare-earth elements (Eu, Sm, Dy and Gd), Hf and Cd contents in sinterized U and Th mixed oxides by neutron activation analysis. The sample is dissolved in nitric/fluoridric (0,1% HF) medium, to dryness and redissolved in 6N HCl solution. The Hf is extracted into organic phase (0,5 M TTA/benzene), irradiated and analysed through 181Hf isotope energy peak. The aqueous phase is treated with NH4OH for the precipitation of hidroxides. Then, these are dissolved in 6N HNO3 solution. The extraction of U and Th is made in two steps, one with TBP/CCl4 and another with 0,5 M TTA/C6H6. Then the rare-earth elements and Cd are irradiated and determined by gamma spectrometry. (author)

Abstract (Portuguese)

Apresenta-se o desenvolvimento de um metodo para a determinacao dos teores de elementos terras-raras (europio, samario, disprosio e gadolinio), hafnio e cadmio em pastilhas sinterizadas de oxido misto de uranio e torio por ativacao neutronica. A amostra e dissolvida em meio nitrico/fluoridrico (0,1% HF), levada a secura e redissolvida em solucao 6N de HCl. O Hf e extraido para a fase organica (0,5 M TTA/C6H6), irradiado e analisado pelo pico de energia do isotopo 181Hf. A fase aquosa e tratada com NH4OH para a precipitacao dos hidroxidos. Estes, por sua vez, sao dissolvidos em solucao 6N de HNO3. A extracao do uranio e torio e feita em duas etapas, uma com TBP/CCl4 e a outra com 0,5 M TTA/C6H6. Os elementos terras-raras e o cadmio sao, entao, irradiados e determinados por espectrometria gama. (autor)

Files

19054387.pdf

Files (1.2 MB)

Name Size Download all
md5:12fbf0baa62f34d562cdd90df960a9d5
1.2 MB Preview Download

Additional details

Additional titles

Original title (Portuguese)
Determinacao de elementos terras-raras, hafnio e cadmio em pastilhas sinterizadas de oxido misto de torio e uranio por ativacao neutronica

Publishing Information

Imprint Pagination
105 p.
Report number
INIS-BR--1065