SBIR Phase I: Closed-Loop Lithium Reduction of Pure Scandium Metal

这个小型企业创新研究第一阶段项目的更广泛的影响/商业潜力是降低成本，并改善商业化前景，开发具有非凡强度、可焊性、适合3D打印以及新的形状记忆和其他性能的新型轻质含Sc合金。金属钪的价格为每公斤3500-4000美元(是白银价格的6-7倍)，是其氧化物以金属为基础的价格的两倍多，后者约为每公斤1800美元。这阻碍了新合金的商业部署，使其超出了小规模的实验室演示。随着世界各地新的氧化钪矿山和生产设施在未来5-10年内将产量从每年仅10-15吨提高到数百吨，这将降低氧化物的成本。该奖项支持的新的高产量技术旨在大幅降低将氧化物转化为金属的成本，弥合这一差距，使含Sc的合金更适用于高性能应用。这反过来将使新的轻质高性能合金能够取代钢和钛，在提高强度的同时大幅减轻航空零部件的重量。这一阶段研究项目的技术目标是在实验室规模上证明一种全新的生产工艺的可行性，该工艺用于从其氧化物中生产纯金属钪。由于氧化钪是元素周期表中最稳定的氧化物，还原成金属首先需要在700℃与氢氟酸(HF)反应生成氟化钪，然后在1600℃的焊接难熔金属锅(通常是钽)中使用金属钙进行金属热还原。金属钙是一种必须通过蒸馏去除的污染物。这些操作导致金属钪的价格为3500-4000美元/公斤，这是其氧化物金属成本的两倍多(1200美元/公斤的氧化钪导致1840美元/公斤的Sc)。由该奖项资助的新工艺将避免使用任何HF，使其更安全、成本更低。它将在一个紧密的闭环系统中保留非常接近100%的钪和其他试剂，从而减少排放和成本。如果在钪上成功，这种方法将很容易地应用于重稀土和金属，如Gd、Dy和Y。

The broader impact/commercial potential of this Small Business Innovation Research Phase I project is to reduce the cost, and improve commercialization prospects, for new light-weight scandium-containing alloys with extraordinary strength, weldability, fitness for 3-D printing, and new shape memory and other properties. At $3500-4000/kg (6-7 times the price of silver), the price of scandium metal is more than twice the metals-basis price of its oxide, which is about $1800/kg. This has deterred commercial deployment of new alloys beyond small-scale laboratory demonstrations. As new scandium oxide mines and production facilities around the world boost production from just 10-15 tonnes per year (TPY) to several hundred tons per annum in the next 5-10 years, this will reduce the cost of the oxide. The new high-yield technology supported by this award aims to dramatically reduce the cost of converting oxide to metal, bridging the gap to make alloys with scandium more viable for high-performance applications. This in turn will enable new light-weight high-performance alloys to replace steel and titanium, dramatically reducing the weight of aerospace parts while improving strength.The technical objectives in this Phase I research project are to demonstrate feasibility at laboratory scale of key unit operations of a brand new production process for pure scandium metal production from its oxide. Because Scandium oxide is the most stable oxide in the periodic table, reduction to the metal first requires reaction with hydrofluoric acid (HF) at 700C to produce scandium fluoride, then metallothermic reduction using calcium metal at 1600C in a welded refractory metal retort (usually tantalum). Calcium metal is a contaminant which must be removed by distillation. These operations result in a price of scandium metal at $3500-4000/kg, which is more than twice the metals-basis cost of its oxide ($1200/kg Scandium oxide leads to $1840/kg Sc). The new process funded by this award will avoid any use of HF, making it safer and less costly. It will retain very close to 100% of the scandium and other reagents in a tight closed-loop system, reducing emissions and costs. If successful with scandium, this method will readily apply to heavy rare earth and metals such as gadolinium, dysprosium and yttrium.