Complexation of vanadium with amidoxime and carboxyl groups: uncovering the competitive role of vanadium in uranium extraction from seawater

Author:

Wang Cong-Zhi1,Wu Qun-Yan1,Lan Jian-Hui1,Chai Zhi-Fang12,Wu Guo-Zhong3,Shi Wei-Qun1

Affiliation:

1. Laboratory of Nuclear Energy Chemistry and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety , Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100049 , China

2. School of Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions , Soochow University , Suzhou 215123 , China

3. Shanghai Institute of Applied Physics, Chinese Academy of Sciences , Shanghai 201800 , China

Abstract

Abstract At present, amidoxime-based adsorbents are considered to be the most promising materials for extraction of uranium from seawater. However, the high concentrations of transition metals especially vanadium strongly compete with uranium in the sequestration process, which is extremely limited the commercial use of amidoxime-based adsorbents. In this work, the coordination modes, bonding nature, and stabilities of possible vanadium(IV) (VO2+) and (V) (VO2 +, VO3+, V5+) complexes with amidoximate (AO), carboxyl (Ac), glutarimidedioximate (HA) and deprotonated glutarimidedioximate (A2−) on single and double alkyl chains (R=C13H26) are systematically explored by quantum chemical calculations. Different from the uranyl (UO2 2+) complexes, the AO groups of the vanadium(IV) and (V) complexes prefer to coordinate as monodentate and chelate ligands, while few species with AO groups in η2-binding mode have been observed in the vanadium complexes. Besides, the vanadium complexes are predicted to have obvious covalent metal-ligand bonds. According to thermodynamic stability analysis, all the vanadium complexes with AO, Ac, HA and A2− ligands on double alkyl chains are found to be more stable than corresponding complexes with ligands on a single chain. The synergistic effect of the amidoxime and carboxyl groups can be observed in most of VO2 + and VO3+ complexes with mixed ligands (AO/Ac). The vanadium(IV) and (V) complexes are more stable than the corresponding uranyl complexes, and the adsorption capability of the amidoxime-based adsorbents toward vanadium(V) ions decrease in the order of VO2 +>VO3+> V5+. The dioxovanadium cation VO2 + is predicted to form multinuclear vanadium complex in the sequestration process, possibly resulting in higher stable VO2 + complexes. Therefore, the higher complexation ability of the amidoxime-based adsorbents toward vanadium over uranium is probably due to the differences in the coordination modes and bonding nature. The current results might provide important clues for rational design of efficient ligands in sequestration of uranium from seawater.

Publisher

Walter de Gruyter GmbH

Subject

Physical and Theoretical Chemistry

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3