内蒙古工业大学文献检索第3单元(3)

Author

Ibrahim E. El Aassy , Afaf A. Nadab, a a

a

Mohamed M. El Galy , Mohamed G. El Feky , Thanaa M. Abd El Maksoud , Shadia M. Talaat , Eman M. Ibrahima b b

Source

Applied Radiation and Isotopes Volume 70, Issue 6, June 2012, Pages 1024–1033 The hydrometallurgy of radionuclides means getting the

Abstract

radioelements from the rocks into solution by leaching, getting the radionuclides from the solution by extraction process, and then precipitation of the desired elements to obtain concentrate. The follow-up of the radionuclides during these processes is the main target of this work to identify the identity of the original samples, pregnant solutions (leachates), residuals and the concentrate. Six samples were chosen to achieve this work. The leaching process was carried out under the conditions; 20–30% acid (H2SO4) concentration, 1:3 solid/liquid ratios, 60 min stirring time at room temperature. The activity concentrations of226 238

U,

235

U,

234

U,

Ra,

214

Pb,

214

Bi,

232

Th and K were measured in the original samples,

40

residuals and U-concentrate (Bq/kg), and leachates (Bq/ ).

The results indicate that, the radionuclides before214

226

Ra in the226 40

238

U

decay series are more leachable (released) than those from Bi in the order;234

Ra to

U> U= U

238

235

226

Ra> Pb> Bi.

214

214

232

Th and

K are

immobile under the present conditions. The radiological hazards of natural radioactivity in the original samples, leachates, residuals and U-concentrate were calculated and compared with the internationally recommended values and were found to be much higher than the world average values.