Preparation and Properties of Ceramic Solidified Product Containing Cs and Sr

137Cs and 90Sr in high level liquid waste, with high radioactivity, large heat-generating and relatively long half-life. In order to solve the problem of final disposal of 137Cs and 90Sr, natural mineral allophane was chosen as the base materials to synthesize the silicate ceramic solidified products with cold pressing/sintering method. The microstructure, phase composition and surface element distribution of the solidified products were analyzed. The solidification mechanism of the solidified products was also discussed. The surface of the solidified products appeared melting phenomenon after sintering, and the structure was more compact. CsAlSiO4, Sr2Al2SiO7 and SrAl2Si2O8, which can stably solidify Cs and Sr, were formed in the solidified products. The content of allophane in the solidified product has an important influence on the immobilization ratio of Cs and Sr. And at the sintering condition of 1 h duration time at 1200 °C, the immobilization ratios of Cs and Sr can reach 100 %. By increasing the content of cured substrate, the surface characteristics and crystallization properties of the solidified product can be improved, and the volume reduction effect was more obvious.