Measurement of the leaching rate of radionuclide ~(134)Cs from the solidified radioactive sources in Portland cement mixed with microsilica and barite matrixes

摘要

Portland cement was mixed with radionuclide ~(134)Cs to produce low-level radioactive sources. These sources were surrounded with cement mixed with different materials like microsilica and barite. The leaching rate of ~(134)Cs from the solidified radioactive source in Portland cement alone was found to be 4.481 × 10~(-4) g/cm~2 per day. Mixing this Portland cement with microsilica and with barite reduced significantly the leaching rate to 1.091 × 10~(-4) g/cm~2 per day and 3.153 × 10~(-4) g/cm~2 per day for 1 wt.% mixing, and to 1.401 × 10~(-5) g/cm~2 per day and 1.703 × 10~(-4) g/cm~2 per day for 3 wt.% mixing, respectively. It was also found that the application of a latex paint reduced these leaching rates by about 6.5%, 20.3% and 13.3% for Portland cement, cement mixed with microsilica and with barite, respectively. The leaching data were also analyzed using the polynomial method. The obtained results showed that cement mixed with microsilica and with barite can be effectively used for radioactive sources solidification.