Recovery of technologically critical lanthanides from ion adsorption soils
Recovery of technologically critical lanthanides from ion adsorption soils
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DOI：
10.1016/j.mineng.2021.106921
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发表时间：
2021-07
影响因子：
4.8
通讯作者：
A. Stockdale;S. Banwart
中科院分区：
文献类型：
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作者：
A. Stockdale;S. Banwart
由于在消费技术、汽车工业和可再生能源发电系统以及其他技术领域的使用迅速增加，稀土元素（ree）的需求不断增加。离子吸附型稀土矿床目前在中国南部省份被开发，并且在全球范围内发现潜在储量的兴趣越来越大。在这里，我们研究了从马达加斯加表层沉积物中提取离子吸附粘土样品中的稀土元素。使用1 M NH4Cl盐溶液，根据实验证据选择，以最大限度地提取REE，最大限度地减少洗脱液中不需要的溶解Al。在提取过程中，较低的Al浓度降低了其对NH4+在草酸沉淀中稀土元素的干扰。研究表明，在通流柱体系中，NH4Cl溶液可以在相对较低的溶剂体积下有效地提取稀土元素。我们发现，当用浸出剂脉冲萃取后再进行冲洗时，萃取过程中有几个可识别的阶段，包括萃取总镧系元素的显著增加，这与铵离子的突破有关，洗脱的溶解铝浓度从峰值浓度下降。
Rare earth elements (REEs) are in increasing demand due to rapidly rising use in consumer technology, the automotive industry and in renewable energy generation systems, amongst other technology sectors. Ion-adsorption type REE ore deposits are currently being exploited in China’s southern provinces and there is increasing interest in identifying potential reserves globally. Here we investigated the extraction of REEs from an ion-adsorption clay sampled at a surficial deposit in Madagascar. Using a 1 M NH4Cl lixiviant salt solution, chosen based on experimental evidence to maximise REE extraction, minimises undesirable dissolved Al in eluate. Lower Al concentration in solution reduces its interference with NH4+in oxalate precipitation of REEs in the extraction process. We show that NH4Cl solutions can be used to efficiently extract REE with relatively low lixivient volumes in a through-flow column system. We show that when extraction with a pulse of lixiviant is followed by a rinsing step, there are several identifiable stages during the extraction process, including a marked increase in total lanthanides extracted, which is correlated with the breakthrough of ammonium ions, and where the eluted dissolved Al concentration decreases from its peak concentration.