Synthesis of amorphous KAlSi3O8 for cesium radionuclide immobilization into solid matrices using spark plasma sintering technique

An effective sorption material for cesium radionuclides immobilization in highly safe and reliable solid-state matrices was proposed. Prepared aluminosilicate (KAlSi3O8) adsorbent had amorphous mesoporous structure and Cs+ ions sorption capacity of similar to 3.7 mmol/g . The physical-chemical characteristics of (Cs, K)AlSi3O8 sample saturated with Cs+ ions were studied using XRD, FT-IR, SEM-EDX, and DTA-TG methods. Firstly, solid-state aluminosilicate matrices were obtained using spark plasma sintering (SPS) technology with high values of relative density (up to 99.9%), compressive strength (31.3-79.2 MPa), and Vickers microhardness (0.9-5.3 GPa). The sample obtained at 1000 degrees C had a low value of Cs+ leaching from matrices (R-Cs within the range of 10(-7) g cm(-2).day(-1)) and cesium diffusion coefficient (D-e 9.07 x 10(-14) cm(2)/s). It was shown that prepared aluminosilicate cesium matrices comply with regulatory requirements of GOST R 50926-96 and ANSI/ANS 16.1.