Solvent Extraction Circuit of Niobium from Chloride leachate

铌（Nb）是现代先进技术的战略材料，包括医疗器械、光学透镜、超导射频腔、电磁辐射探测器等。由于铌中的微量杂质在上述应用中是不可容忍的，因此生产纯铌是湿法冶金工业的重要目标。溶剂萃取（SX）法是目前分离金属以获得高纯度产品的唯一实用方法。用于回收Nb的大多数商业化SX工艺在氟离子（HF）的存在下操作，主要在与硫酸（H2SO 4）的混合物中。然后用水或稀硫酸从有机相中反萃取络合铌氟化物，然后可以用氨沉淀。然而，由于对人类健康和环境保护的严格规定，应减少或消除使用有害的氟化物。因此，开发使用更清洁的溶液而不是氟化物的提取工艺具有很大的兴趣。GeoMegA是一家矿产勘探和开发公司，专注于魁北克省经济矿藏的发现和可持续发展，旨在以创新工程脱颖而出。该公司开发了使用盐酸（HCl）提取稀土元素（REE）的工艺。然而，稀土萃取后的剩余浸出液中含有大量的Nb，值得回收。GeoMegA希望与在萃取工艺方面具有丰富经验的CEOSQQ（魁北克化学工艺研究中心）合作开发从盐酸浸出液中萃取铌的工艺。本项目的目标是在Montviel湿法冶金工艺中从焦磷酸钠-硅酸盐混合物中提取铌。需要溶剂萃取回路来从氯化物溶液中回收和纯化Nb。

Niobium (Nb) is a strategic material for many modern advanced technologies including medical devices, optical lens, superconducting radio frequency cavities, electromagnetic radiation detector, etc. Since the impurity even in trace amounts in Nb cannot be tolerated for the above applications, producing pure Nb is of great interest to hydrometallurgical industry. Solvent extraction (SX) method is currently the only practical way for separating metals to obtain high purity products. Most of commercialised SX processes for recovery of Nb are operated in the presence of fluoride ions (HF), mostly in a mixture with sulphuric acid (H2SO4). The complex niobium fluorides are then re-extracted from organic phase with water or dilute sulfuric acid and then can be precipitated with ammonia. However, due to stringent regulations concerning the human health and environment protection, using harmful fluorides should be reduced or eliminated. Therefore, developing an extraction process using cleaner solutions instead of fluorides is of great interest. GeoMegA, a mineral exploration and development company focused on the discovery and sustainable development of economic deposits in Québec, aims to distinguish itself with innovative engineering. The company has developed Rare Earth Elements (REE) extraction processes using hydrochloric acid (HCl). However, the remaining leachate after REE extraction contains significant amount of Nb which worth recovering. GeoMegA would like to develop Nb extraction process from HCl leachate in collaboration with CEPROCQ (Center of study of chemical processes of Quebec), which has a great experience in extraction processes. The objective of this project is the extraction of Nb from a mixture of Pyrochlore-silicate at Montviel hydrometallurgy process. The solvent extraction circuit is required to recover and purify Nb from chloride solution.