The fate of rhenium in polyaminocarboxy solution: Hourglass crystal and its speciation study

• Published in: Journal of hazardous materials Vol. 375; pp. 78 - 85
• Main Authors: Fu, Zhihai, He, Aidan, Min, Xiaowen, Ding, Mu, Chen, Tao, Zhai, Fuwan, An, Shuwen, Xiao, Fengfeng, Kang, Jinyang, Ding, Jie, Huang, Chao, Feng, Xiaojie, Jin, Yongdong, Xia, Chuanqin
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 05.08.2019
• Subjects: Hourglass crystal; Polyaminocarboxy; Reduction; Rhenium; Reduction; Rhenium; Polyaminocarboxy; Hourglass crystal
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2019.04.059

[Display omitted] •The low valent Re complex in the reduction solution was in-situ analysis by EXAFS and UV–vis.•The hourglass crystal of Re was firstly prepared.•The speciation of Re in the hourglass cyrstal was low valent dimeric Re-DTPA by EXAFS and DET calculation.•The low valent Re in the hourglass crystal is stable in the air. This paper studied the fate of Re in the presence of polyaminocarboxy ligand (DTPA, EDTA and NTA) under reducing condition. When SnCl2 as reducing agent, the results indicated the low valent Re was formed. And batch experiments studied the effect of pH and different ligands on the formation of low valent Re complex, the acid condition was favoured for the formation of low valent Re complex, and the order of complexing toward the low valent Re was the following: DTPA > EDTA > NTA. In the condition of pH = 1, DTPA as ligand, the hourglass crystal was obtained. Using ESI-MS, solid-state UV–Vis–NIR spectra, EXAFS, DFT calculation et al, the darkened patch of the hourglass crystal was demonstrated to be Re, and its speciation was dimeric Re2(μ-O)2DTPA.