Direct separation of minor actinides from high level liquid waste by Me ₂ -CA-BTP/SiO₂-P adsorbent

Directly separating minor actinides (MA: Am, Cm, etc.) from high level liquid waste (HLLW) containing lanthanides and other fission products is of great significance for the whole nuclear fuel cycle, especially in the aspects of reducing long-term radioactivity and simplifying the post-processing separation process. Herein, a novel silica-based adsorbent Me₂-CA-BTP/SiO₂-P was prepared by impregnating Me₂-CA-BTP (2,6-bis(5,6,7,8-tetrahydro-5,8,9,9-tetramethyl-5,8-methano-1,2,4-benzotriazin-3-yl)pyridine) into porous silica/polymer support particles (SiO₂-P) under reduced pressure. It was found Me₂-CA-BTP/SiO₂-P exhibited good adsorption selectivity towards ²⁴¹Am(III) over ¹⁵²Eu(III) in a wide nitric acid range, acceptable adsorption kinetic, adequate stability against γ irradiation in 1 and 3 M HNO₃ solutions, and successfully separated ²⁴¹Am(III) from simulated 3 M HNO₃ HLLW. In sum, considering the good overall performance of Me₂-CA-BTP/SiO₂-P adsorbent, it has great application potential for directly separating MA from HLLW, and is expected to establish an advanced simplified MA separation process, which is very meaningful for the development of nuclear energy.