Solvent Extraction of Technetium(VII) and Rhenium(VII) Using a Hexaoctylnitrilotriacetamide Extractant

Kojiro Shimojo; Hideya Suzuki; Keiichi Yokoyama; Tsuyoshi Yaita; Atsushi Ikeda-Ohno

doi:10.2116/analsci.20C014

Solvent Extraction of Technetium(VII) and Rhenium(VII) Using a Hexaoctylnitrilotriacetamide Extractant

Anal Sci. 2020 Dec 10;36(12):1435-1437. doi: 10.2116/analsci.20C014. Epub 2020 Nov 13.

Authors

Kojiro Shimojo^{1

2}, Hideya Suzuki³, Keiichi Yokoyama⁴, Tsuyoshi Yaita⁴, Atsushi Ikeda-Ohno⁵

Affiliations

¹ Materials Sciences Research Center, Japan Atomic Energy Agency (JAEA), 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo, 679-5148, Japan. shimojo.kojiro@jaea.go.jp.
² Institute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, Dresden, 01328, Germany. shimojo.kojiro@jaea.go.jp.
³ Nuclear Science and Engineering Center, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Tokai-mura, Ibaraki, 319-1195, Japan.
⁴ Materials Sciences Research Center, Japan Atomic Energy Agency (JAEA), 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo, 679-5148, Japan.
⁵ Institute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, Dresden, 01328, Germany.

PMID: 33191366
DOI: 10.2116/analsci.20C014

Abstract

Liquid-liquid extraction for the removal of pertechnetate (⁹⁹TcO₄^-) and perrhenate (ReO₄^-) is reported based on using the tripodal extractant N,N,N',N',N″,N″-hexa-n-octylnitrilotriacetamide (HONTA) composed of three amide groups and a tertiary amine. The extraction behaviors were compared with those using alkyldiamideamines (ADAAM(Oct) and ADAAM(EH)), and the commercial amine-type extractant, trioctylamine (TOA). HONTA quantitatively extracted ⁹⁹TcO₄^- and ReO₄^- in the pH range from 1.0 to 2.5 by the co-extraction of protons. The extraction performance of the extractants was improved in the order of HONTA > ADAAM(Oct) > ADAAM(EH) > TOA. ⁹⁹TcO₄^- and ReO₄^- in the extracting phase were successfully stripped using neutral aqueous solutions as the receiving phase, and the extraction ability of HONTA was maintained after five repeated uses.

Keywords: Solvent extraction; amide-type ligand; amine-type ligand; novel extractant; rhenium; technetium.