title: Highly efficient extraction of actinides with pillar[5]arene-derived diglycolamides in ionic liquids via a unique mechanism involving competitive host-guest interactions.
abstract: Actinide partitioning is considered as one of the most challenging issues in nuclear waste remediation. Herein, we unravel a novel extraction mode pertinent to the competitive host-guest interactions for highly efficient actinide extraction. The host-guest recognition event involves binding of a room temperature ionic liquid (RTIL), 1-n-octyl-3 methylimidazolium bis(trifluoromethane)sulfonamide (C8mimNTf2), as both the guest and the solvent by the hosts pillar[5]arene-based diglycolamides (P5DGAs) and the subsequent displacement of the guest by a metal ion. This two-step process suggests a unique competitive ion-mediated displacement mechanism for the metal ion partitioning in the extraction process. The supramolecular extraction system is evaluated for its extraction abilities towards actinide ions such as UO22+, PuO22+, Pu4+, Am3+, and fission product elements such as Eu3+, Sr2+, Cs+. The results demonstrate the exceedingly high distribution ratios and favorable separation of Am3+and Pu4+in nitric acid media. All the three P5DGAs form 1 : 1 complexes with Am3+. Time resolved laser fluorescence spectroscopic (TRLFS) studies reveal a strong complexation involving no inner-sphere water molecules in the Eu3+-P5DGA complexes when C8mimNTf2is used as the diluent. With high efficiency in the extraction of actinides and a quantitative back extraction outcome, the RTIL-based solvent systems containing pillar[5]arene-DGA ligands developed in this work hold potential as promising candidates for nuclear waste remediation in a more sustainable fashion.
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Caixia
authors.initials: C
authors.lastname: Li
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Lei
authors.initials: L
authors.lastname: Wu
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Lixi
authors.identifier: http://orcid.org/0000-0002-4694-6737
authors.initials: L
authors.lastname: Chen
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Yuan
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Yimin
authors.initials: Y
authors.lastname: Cai
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Wen
authors.initials: W
authors.lastname: Feng
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Yi
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India. arijita@barc.gov.in.
authors.forename: Arijit
authors.initials: A
authors.lastname: Sengupta
authors.affiliation: Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India. arijita@barc.gov.in.
authors.forename: Mallekav S
authors.initials: MS
authors.lastname: Murali
authors.affiliation: Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India. arijita@barc.gov.in.
authors.forename: Prasanta K
authors.initials: PK
authors.lastname: Mohapatra
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Guohong
authors.initials: G
authors.lastname: Tao
authors.affiliation: Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos, Singapore 138669, Singapore.
authors.forename: Huaqiang
authors.initials: H
authors.lastname: Zeng
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Songdong
authors.initials: S
authors.lastname: Ding
authors.affiliation: College of Chemistry, Institute of Nuclear Science and Technology, Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064, China. lhyuan@scu.edu.cn wfeng9510@scu.edu.cn.
authors.forename: Lihua
authors.identifier: http://orcid.org/0000-0003-0578-4214
authors.initials: L
authors.lastname: Yuan