Elemental groups separation for high-level waste partitioning using a novel silica-based CMPO extraction-resin

シリカを基材とした新しいCMPO抽出樹脂による高レベル廃液からの元素群分離

星 陽崇*; Wei, Y.*; 熊谷 幹郎*; 朝倉 俊英; 内山 軍蔵* 

Hoshi, Harutaka*; Wei, Y.*; Kumagai, Mikio*; Asakura, Toshihide; Uchiyama, Gunzo*

われわれは、高レベル廃液(HLLW)の管理を容易にし、地層処分時の長期放射線リスクを最小化するために、用いる有機溶媒が最小量で済み、装置がコンパクトな抽出クロマトグラフィーによりHLLWから長半減期のマイナーアクチノイド(MA)やZrやMoのような核分裂生成物(FP)を分離する、高度な元素群分離プロセスを提案してきた。本研究では、マクロレティキュラー型スチレン-ジビニルベンゼン共重合体が直径50mの多孔性シリカ粒子内に固定された担体(SiO-P)にCMPO (octyl(phenyl)-N, N-diisobutylcarbamoylmethylphosphine oxide)を担持した新しい抽出樹脂を調整し、トレーサー量のAm(III)とマクロ量の典型的なFP元素を含む模擬HLLWを用いて、カラムクロマトグラフィーによる分離実験を行い、その結果、模擬HLLW中の元素を3つの群、すなわちCs-Sr-Rh-Ru群,Pd-Ln-Am群及びZr-Mo群に分離することに成功した。

To facilitate the management of high-level liquid waste (HLLW) and minimize its long-term radiological risk in geologic disposal, we have proposed an advanced partitioning process by extraction chromatography using a minimal organic solvent and compact equipment to separate long-lived minor actinides (MA) and specific fission products (FP) such as Zr and Mo from nitrate acidic HLLW solution. Novel silica-based extraction-resin for elemental groups separation was prepared by impregnating CMPO (octyl(phenyl)-N, N-diisobutylcarbamoylmethylphosphine oxide) into a macro-reticular styrene-divinylbenzene copolymer immobilized in porous silica particles with a diameter of 50 m (SiO-P). Separation experiments for simulated HLLW solutions containing a trace amount of Am (III) and macro amounts of typical FP elements were carried out by column chromatography. It was found that the elements in the simulated HLLW were successfully separated to the following three groups: Cs-Sr-Rh-Ru, Pd-Ln-Am and Zr-Mo.