Separation Science and Technology, Vol.41, No.11, 2409-2427, 2006
Strontium and actinide separations from high level nuclear waste solutions using monosodium titanate 2. Actual waste testing
Pretreatment processes at the Savannah River Site will separate Sr-90, alpha-emitting and radionuclides (i.e., actinides) and Cs-137 prior to disposal of the high-level nuclear waste. Separation of Sr-90 and alpha-emitting radionuclides occurs by ion exchange/adsorption using an inorganic material, monosodium titanate (MST). Previously reported testing with simulants indicates that the MST exhibits high selectivity for strontium and actinides in high ionic strength and strongly alkaline salt solutions. This paper provides a summary of data acquired to measure the performance of MST to remove strontium and actinides from actual waste solutions. These tests evaluated the effects of ionic strength, mixing, elevated alpha activities, and multiple contacts of the waste with MST. Tests also provided confirmation that MST performs well at much larger laboratory scales (300 - 700 times larger) and exhibits little affinity for desorption of strontium and plutonium during washing.