Solvent extraction of actinides and fission products by amides and crown ether compounds

Sasaki, Yuji  ; Suzuki, Shinichi; Morita, Keisuke 

Many kinds of metals with high concentration exist in high level radioactive waste (HLW). Most of metals have high radioactivity and strong heat, then there should be removed from aqueous phase. Target metals in HLW are as follows, actinides, lanthanides, zirconium, molybdenum, technetium, cesium, strontium, and palladium, due to long range radioactivity, huge environmental burden, and high concentration then troublemsome metals. We try to separate these metals by solvent extraction. Actinides and lanthanides can be extracted by TODGA (tetraoctyl-diglycolamide) from nitric acid, Zr is done by malonamide (or HDEHP), Mo, Re (substitution for Tc) and Pd can be extracted by MIDOA (methylimino-dioctylacetamide), and Sr and Cs can be removed by crown ether compounds. These extractants, except for HDEHP, belong to CHON compounds, which leads less secondary waste generation.