Metalysis Fray Farthing Chen Process As a Strategic Lunar <i>In Situ</i> Resource Utilization Technology
Alex Ellery, Ian Mellor, Priti Wanjara, Melchiorri Conti
Abstract
Crucial to permanent occupation of the Moon will be the exploitation of local resources to build a lunar infrastructure. We examine 2 processes—the Metalysis Fray Farthing Chen (FFC) process and metal three-dimensional (3D) printing—as the backbone of a robust and sustainable industrial ecology on the Moon to exploit its raw material resources with husbandry. The Metalysis FFC process is an electrochemical technique that can extract near pure metals from their oxide and silicate forms through cathodic reduction. An anode (graphite) and cathode (metal oxide to be reduced) reside in a bath of molten salt CaCl 2 at 900–1,100°C. A voltage is applied and the metal oxide releases oxygen ions into the molten salt, and oxygen is released at the cathode and transferred to the anode as CO or CO 2 gas if the anode is graphite. At the cathode, the metal oxide is reduced into metal plus oxygen through a series of intermediate steps. We outline how the Metalysis FFC process can be leveraged through a handful of chemical preprocessing methods to exploit its versatility. We have demonstrated some preliminary experiments in extracting Ti metal powder from rutile through the Metalysis FFC process, which was subsequently 3D printed into Ti test structures using selective laser sintering. These 2 methods—Metalysis FFC and metal 3D printing—offer unprecedented capabilities for a lunar infrastructure manufacturing chain. In particular, we take note of their high-energy efficiency that will be crucial to lunar in situ resource utilization.