Plasma Extraction of Metals in Space

Abstract

Extraction of purified metals from extraterrestrial materials can be accomplished in several ways, such as beneficiation, hydrogen reduction, recovery of spent rockets, direct melting of iron meteorites, and plasma isotope separation. Presented here is a method for multiple simultaneous extraction of multiple metals and metalloids from regolith. Two patented approaches are described which can operate on a planetary surface, or in the microgravity environment of orbit. This approach to isotope separation applies to regolith fines but is advantageously applied to the effluent of a patented oxygen extraction method. In this way, a plurality of valuable raw materials can be obtained with a single system, suitable for operation on the Moon or at the surface of an asteroid. Silicon is of interest for studies of purity due to its importance in photovoltaics. A silicon-aluminum aerospace alloy can be produced directly, called Silumin, which has value in construction of habitats and space craft in space. Silicon can also be combined with carbon to form the wide-bandgap semiconductor SiC from which high-power and radiation-tolerant power transistors can be fabricated. Furthermore, this method lends itself to additive manufacturing whereby specific shapes of purified metals can be formed directly from the plasma extraction process.