Effect of reduced dehalogenation on the performance of Y zeolite-based sintered waste forms

Abstract The properties of a dehalogenated salt waste form (DSWF) were investigated for the immobilization of electrorefiner salt waste from the pyrometallurgical reprocessing of used nuclear fuel. Dehalogenation of salt through reaction with hydrogen-Y zeolite provides a viable means of decreasing solid waste volume prior to immobilization. The presence of residual salt (from insufficient dehalogenation reaction time or inefficient operation) on waste form properties is also evaluated via hot stage X-ray diffraction and leach testing. Residual salt appears to volatilize during sintering, producing a secondary waste stream. The kinetic dissolution rates of DSWFs show evidence of congruent dissolution and exhibit lower dissolution rates compared to the baseline GBS advanced ceramic waste form. Additional characterization is required to determine behavior due to saturation effects.