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

这个小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，改善商业化前景，新的轻质含钪合金具有非凡的强度，可焊接性，适合3d打印，新的形状记忆和其他性能。钪金属的价格为3500-4000美元/公斤（银价格的6-7倍），是其氧化物金属基价格（约1800美元/公斤）的两倍多。这阻碍了新合金在小规模实验室演示之外的商业应用。随着世界各地新的氧化钪矿山和生产设施将产量从每年10-15吨（TPY）提高到未来5-10年的每年数百吨，这将降低氧化物的成本。该奖项支持的新高产量技术旨在大幅降低将氧化物转化为金属的成本，弥合差距，使含钪合金更适用于高性能应用。这反过来又将使新的轻质高性能合金取代钢和钛，在提高强度的同时大大减轻航空航天零件的重量。本一期研究项目的技术目标是在实验室规模上论证一种全新的从其氧化物中生产纯金属钪的生产工艺的关键单元操作的可行性。由于氧化钪是元素周期表中最稳定的氧化物，还原为金属首先需要与氢氟酸（HF）在700C下反应生成氟化钪，然后在焊接的难熔金属烧罐（通常是钽）中使用金属钙在1600C下进行金属热还原。金属钙是一种污染物，必须用蒸馏法去除。这些操作导致钪金属的价格在3500-4000美元/公斤，这是其氧化物金属成本的两倍多（1200美元/公斤氧化钪导致1840美元/公斤钪）。由该合同资助的新工艺将避免使用HF，使其更安全，成本更低。它将在严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。如果在钪上取得成功，这种方法将很容易适用于重稀土和金属，如钆、镝和钇。

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.