从含化水溶液中提取Se (iv) 和Se (vi),使用含胺的三级胺
Hirokazu Narita1, Motoki Maeda2, Chiharu Tokoro2
1Global Zero Emission Research Center, National Institute of Advanced Industrial Science and Technology (AIST) 16-1 Onogawa Tsukuba Ibaraki 305-8569 Japan hirokazu-narita@aist.go.jp.
RSC advances
|June 8, 2023
概括
这项研究探讨了使用EHBAA.的从HCl溶液中提取. (VI) 降解为 (IV) 在缩的HCl中,EHBAA通过不同的机制来促进提取,这取决于的氧化状态和HCl度.
科学领域:
- 无机化学 无机化学 有机化学
- 水电金术是指用水电金术进行金术.
- 分离科学 分离科学
背景情况:
- 在水溶液中的物种化对于环境和工业过程至关重要.
- N-2-乙烯基二 (N-di-2-ethylhexyl-ethylamide) 胺 (EHBAA) 是一种金属离子的潜在提取剂.
- 了解物种的提取机制对于有效分离至关重要.
研究的目的:
- 通过使用EHBAA,研究从水性HCl溶液中提取 (IV) 和 (VI) 的提取机制.
- 为了阐明提取的物种的结构性质.
- 为了确定HCl度对提取效率的影响.
主要方法:
- 用Se(IV) 或Se(VI) 制备水性HCl溶液.
- 边缘附近的X射线吸收结构 (XANES) 和扩展的X射线吸收细结构 (EXAFS) 分析.
- 采用不同度的取实验和斜率分析来确定石化学.
主要成果:
- 在8M HCl.中,Se(VI) 降解为Se(IV).
- EHBAA从0.5M HCl中提取了~50%的Se(VI),从>5M HCl中提取了~85%的Se(IV).
- 提取的Se(IV) 和Se(VI) 物种分别被确定为[SeOCl2]和[SeO4]2-.
结论:
- 通过EHBAA从8M HCl中提取,通过溶解机制进行 (1:1固态测量).
- 通过EHBAA从0.5M HCl中提取Se(VI) 采用一个离子交换机制 (1:2石化学).
- 根据氧化状态和HCl度,EHBAA证明了物种的选择性提取能力.
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