Study on separation of platinum group metals from high level liquid waste using macroporous (MOTDGA-TOA)/SiO-P silica-based absorbent

Ito, Tatsuya  ; Kim, S.-Y.*; Xu, Y.*; Hitomi, Keitaro*; Ishii, Keizo*; Nagaishi, Ryuji ; Kimura, Takaumi 

To research recovering of platinum group metals (PGMs) from high level liquid waste (HLLW) by macroporous silica-based adsorbent, the adsorbent of (MOTDGA-TOA)/SiO-P was developed by impregnating two extractants of N,N'-dimethyl-N,N'-di-n-octyl-thiodiglycolamide (MOTDGA) and tri-n-octylamine (TOA) into a silica/polymer composite support (SiO-P). The adsorbent showed good adsorption property for Pd(II). In addition, the combined use of MOTDGA and TOA improved adsorption of Ru(III) and Rh(III) better than the individual use of them. The usability of adsorbent in radiation fields was further confirmed by irradiation experiments. The adsorbent remained to have adsorption capability for PGMs at least adsorbed dose of 100 kGy, correspomding with one adsorbed by the adsorbent in their adsorption, and showed good retention capability for adsorbed Pd(II) even at the adsorbed dose of 800 kGy.