Fly Ash Based Geopolymers Solidification Material Modified by Blending With Natural Zeolite

Geopolymers have a zeolite- like structure and are the precursors of zeolite. They are expected to be a kind of good materials for solidification of radwaste. The optimal feeding proportion for synthesis of geopolymers was obtained by orthogonal experiments. Single factor experiments were used to explain the impact of different mass fraction and granularity of zeolite to the mechanical performance of the geopolymers. The geopolymer products were characterized by XRD, IR, SEM, and N₂ adsorption measurements. The following phenomena were observed in 28 d hydrated polymers: the occurrence of zeolite P and analicime-C, the increase in amorphous phase proportion, and the decrease in both the total pore volume and the average pore diameter. We conclude that adding zeolite to geopolymers can improve the structure of the pores and accelerate the hydration. Simulating strontium waste solutions are solidified by this geopolymers, and its leaching rates are measured in different times according to the GB14569.1-1993.