从水溶液中提取稀土元素,使用离子液体三四甲基三二二酸盐
Andreas Gradwohl1, Jakob Windisch1, Matthias Weissensteiner1
1Department of Inorganic Chemistry, University of Vienna Währinger Straße 42 Vienna 1090 Austria franz.jirsa@univie.ac.at.
RSC advances
|August 23, 2023
概括
这项研究表明,三四甲基三二酸盐有效地从水溶液中提取稀土元素. 最佳的提取发生在pH值为2.5,浸出最小,证明其在金属回收方面的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
- 水电金术是指用水电金术进行金术.
背景情况:
- 离子液体为选择性金属提取提供可调节的特性.
- 三基四基三基二酸是一种有前途的提取剂,具有较低的浸出率.
- 稀土元素 (REE) 的回收对于技术应用至关重要.
研究的目的:
- 为了评估三四三二酸对稀土元素 (La,Ce,Nd,Ho,Lu) 的提取效率.
- 为了研究pH值,温度和时间对提取性能和浸出的影响.
- 为了阐明提取机制.
主要方法:
- 进行了单元和双元提取实验.
- 不同的条件包括pH值 (优化为2.5),温度 (20-30°C) 和提取时间 (长达6小时).
- 量化了REE度和漏情况.
主要成果:
- 在室温下6小时内实现Ce,Nd和Lu的高提取效率 (>80%).
- 温度升高显著增强了的提取 (36%在20°C,在2小时后达到80%在30°C),但在单元测试中没有Ce.
- 提取机制被证实为离子交换,pH值变化与疗效正相关. 泄漏仍然很低 (0.8-1.2%) 并不受温度升高的影响.
结论:
- 三四甲基三二甲酸是一种有效的REE提取剂,特别是在酸性条件下 (pH2.5).
- 温度对特定的REEs的提取动力学起着作用,但漏仍然始终很低.
- 阳离子交换机制和低漏凸显了提取剂对可持续REE回收的可行性.
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