HIPed tailored ceramic waste forms for the immobilization of Cs, Sr and Tc

Abstract

The Advanced Fuel Cycle Initiative is developing advanced technologies to allow for the safe and economical disposal of waste from nuclear reactors. An important element of this initiative is the separation of key radionuclides. One of the systems being developed to separate key radionuclides is the UREX+1 process. The Tc and Cs/Sr solutions from UREX+1 process will require treatment and solidification for managed storage. This paper illustrates the benefits of HIPed tailored ceramic waste forms, to provide for the immobilization of separated Cs, Sr and Tc. Experimental data are presented for a Cs and Sr-bearing hollandite-rich tailored ceramic prepared with 12 wt% waste (on an oxide basis). Normalized MCC-1 type leach testing at 90°C for 28 days revealed extremely low Cs and Sr release rates of 0.003 and 0.004 g/m2/day respectively. Experimental data on the immobilization of Tc in titanate ceramics containing up to 40wt% TcO2 are also be presented. © American Nuclear Society