Preparation of Macroporous Silica-based CyMe₄-BTBP/SiO₂-P and Adsorption for Am（Ⅲ） and Eu（Ⅲ）

CyMe₄-BTBP (6, 6′-bis(5, 5, 8, 8-tetramethyl-5, 6, 7, 8-tetrahydrobenzoe1, 2, 4triazin-3-yl)-2, 2′-bipyridine) is a promising extractant for separating An(Ⅲ) from Ln(Ⅲ) in spent fuel reprocessing due to its great selectivity for An(Ⅲ) over Ln(Ⅲ). With optimized procedure, CyMe₄-BTBP was synthesized by using 2, 2′-bipyridine and ester as starting materials, and the purity is 99.5% determined by HPLC. Macroporous silica-based CyMe₄-BTBP/SiO₂-P was prepared by the impregnation and immobilization of CyMe₄-BTBP into the pores of silica-based resin SiO₂-P and characterized by BET, SEM and FT-IR. The effect of the HNO₃ concentration, the CyMe₄-BTBP loading on the adsorbent and the contact time on the adsorption of Am（Ⅲ） and Eu（Ⅲ） was investigated. The adsorption behavior of Am（Ⅲ） and Eu（Ⅲ） on CyMe₄-BTBP/SiO₂-P is different both in thermodynamics and dynamics. The results show that with trace amount of metal ions in aqueous solution and 2.4%-9.1% CyMe₄-BTBP on SiO₂-P, the adsorption of Am（Ⅲ） is much stronger than that of Eu（Ⅲ） and the separation factor is over 100 in 0.1-4 mol/L HNO₃ solution.