Anion-adaptive crystalline cationic material for 99TcO4− trapping

Abstract

Efficient anion recognition is of great significance for radioactive 99 TcO 4 − decontamination, but it remains a challenge for traditional sorbents. Herein, we put forward a tactic using soft crystalline cationic material with anion-adaptive dynamics for 99 TcO 4 − sequestration. A cucurbit[8]uril-based supramolecular metal-organic material is produced through a multi-component assembly strategy and used as a sorbent for effective trapping of TcO 4 − . Excellent separation of TcO 4 − /ReO 4 − is demonstrated by fast removal kinetics, good sorption capacity and high distribution coefficient. Remarkably, the most superior selectivity among metal-organic materials reported so far, together with good hydrolytic stability, indicates potential for efficient TcO 4 − removal. The structure incorporating ReO 4 − reveals that the supramolecular framework undergoes adaptive reconstruction facilitating the effective accommodation of TcO 4 − /ReO 4 − . The results highlight opportunities for development of soft anion-adaptive sorbents for highly selective anion decontamination.

Anion-exchanged and quaternary ammonium functionalized MIL-101-Cr metal-organic framework (MOF) for ReO4−/TcO4− sequestration from groundwater

“…These recent findings open a very attractive avenue for MOF applications for environmental remediation of various contaminants (Mon et al, 2018) and nuclear waste treatment (Banerjee et al, 2016b;Dolgopolova et al, 2018). More recently, several MOFs (Banerjee et al, 2016a;Banerjee et al, 2016c;Drout et al, 2018;Fei et al, 2011;Li et al, 2017b;Mei et al, 2019;Rapti et al, 2018;Sheng et al, 2019;Sheng et al, 2017;Xu et al, 2019;Zhu et al, 2017a) and cationic organic framework (Da et al, 2019;Ding et al, 2020;He et al, 2019;Li et al, 2018;Liu and Han, 2020;Samanta et al, 2018;Shen et al, 2017;Sun et al, 2019;Zhu et al, 2017b) have demonstrated the ability to trap ReO 4 − from aqueous media.…”

Prospects and Challenges in Anion Recognition and Transport

“…55 4B). 56 The authors noted that commercially available ll cucurbituril macrocycles have outwardly pointing CH hydrogen-bond donors that could be utilized for anion recognition upon self-assembly of the macrocycles. They synthesized a 3D supramolecular framework by mixing cucurbit [8] , because of the hydrophobic nature of CH donors.…”

Optimizing Strategy for Enhancing the Stability and 99TcO4– Sequestration of Poly(ionic liquids)@MOFs Composites

“… 30 , 31 As an emerging candidate to sequester TcO 4 – from nuclear waste, metal–organic frameworks (MOFs) are endowed with the unique advantages of tailored porous structures and facile functionalization, relying on their modular building blocks. 32 − 35 Some cationic MOFs exhibit good sorption capability and selectivity to pertechnetate, but slow kinetics, low stability, and poor recyclability under highly acidic conditions. 36 − 38 …”