CONTENT OF URANIUM ISOTOPES IN COALS OF KAZAKHSTAN

Abstract

The content of natural isotopes of uranium (uranium-238 and uranium234) is considered in the presenting paper. The samples of coals from three main coal deposits, located on the territory of Kazakhstan (Karazhyra, Shubarkol and Ekibastuz) were analyzed by alpha-spectrometric method after the corresponding chemical separation, which included separation of radionuclides by liquid-liquid extraction (30% solution of TBP in toluene) and preparation of counting sample by electrodeposition. The measurements were done at the high resolution alpha-spectrometer (Canberra, semiconductor PIPS detectors) and the Alpha Analyst program was used for processing spectra. The content of total uranium increases in the following series: coal of Karazhyra deposit < coal of Shubarkol deposit < coal of Ekibastuz deposit. The results showed that the most safety is coal from Karazhyra coal deposit (0.55±0.12 Bq/kg and 0.85±0.14 Bq/kg for uranium-238 and uranium-234, correspondently). The highest values of concentration of uranium isotopes were recorded for coals of Ekibastuz deposit, but even for it the content of uranium-238 is much lower than the average natural radionuclide activity concentrations in coal.

References

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