ESPLORE (Electrochemical Sustainable Production of indigenous Lunar Oxygen and metals from REgolith) is a joint research project between Maana Electric SA and our Professorship, funded by Luxembourg National Research Fund (FNR) grant 17671424 and Maana Electric SA.

In-Situ Resource Utilization (ISRU) technologies have been identified as a key element to enable sustainable deep-space exploration. Oxygen and metals could be locally extracted from planetary regolith to replace materials that would otherwise be required from Earth, consequently reducing launch masses and costs. Molten Salt Electrolysis (MSE) is a promising ISRU technology that electrochemically reduces solid regolith in a bath of molten salts at temperatures close to 1000°C. Although MSE has an extensive industrial legacy for electrowinning and electrorefining of metals on Earth, the technology transfer to operate such a system reliably and sustainably on the lunar surface is challenging and has not yet been demonstrated. Some of the arising challenges are: the vaporization of molten salts when exposed to the lunar near-vacuum environment, the development of inert anode materials with low corrosion rates that produce gaseous O₂ instead of traditional consumable graphite anodes that produce gaseous CO/CO₂, or the selection of adequate metal post-treatment techniques that avoid the generation of waste products and minimize the cathode degradation.

Therefore, this research project aims to adapt terrestrial industrial MSE techniques to reliably and sustainably operate on the lunar surface, where stricter requirements, derived from intrinsically elevated launch costs and from direct exposure to a harsh space environment, are necessary.