Solid Oxide Membrane (SOM) technology for environmentally sound production of tantalum metal and alloys from their oxide sources

Abstract

The Solid-Oxide-Oxygen-Ion conducting membrane (SOM) technology offers great potential for environment friendly and energy-efficient extraction of high-energy-content metals. This work was performed to demonstrate the technical viability of the SOM technology to produce tantalum metal and tantalum-niobium alloy directly from tantalum oxide and ore concentrates. An electric potential is applied to dissociate the tantalum oxide source, reduce the Ta metal at the cathode, pump the oxygen ions through the membrane (SOM), and oxidize them at the anode. The process can be used to efficiently produce tantalum metal without the expensive pre-processing of raw materials and generation of harmful byproducts. The work reported in this paper demonstrates that the SOM process can produce high-purity tantalum metal. The electrochemical behavior of the cell and the method to increase membrane stability are also discussed.