Lunar Regolith to Oxygen: Advancing Oxygen Extraction for In-Situ Propellant Production

Kurzfassung

Lunar exploration is shifting toward long-term surface presence, necessitating sustainable resource utilization strategies. One of the most significant challenges for deep-space missions is the high cost and impracticality of transporting sufficient propellant for both landing and extended exploration activities. A typical lunar lander utilizing a LOX/LH₂ bipropellant system consumes a substantial amount of oxidizer, with liquid oxygen (LOX) being 16 times heavier per litre than liquid hydrogen (LH₂). By establishing an in-situ oxygen production facility, landers could bring only the necessary fuel, refuelling with locally produced LOX for their return journey or further exploration, significantly reducing mission mass and cost. Lunar regolith, the most abundant natural resource on the Moon, contains a high percentage of oxygen chemically bound in silicates and oxides. Numerous extraction methods have been proposed to liberate this oxygen, often yielding valuable by-products such as metals. However, due to the complex mineral composition of regolith, direct oxygen extraction from raw regolith can be inefficient. Beneficiation processes which selectively concentrate oxygen-rich minerals while separating unwanted components can significantly enhance extraction efficiency and maximize resource utilization. This poster presents results from beneficiation experiments conducted at the German Aerospace Centre (DLR) Bremen, alongside findings from collaborative research projects and previous research studies. The presented work explores how multi-stage beneficiation can improve feedstock composition for oxygen extraction technologies, making ISRU processes more viable and sustainable. In addition, the separation of valuable metal by-products, such as titanium, iron, aluminium and silicon, can enhance the economic feasibility of lunar resource utilization. By integrating beneficiation strategies into ISRU systems, the oxygen recovery can be optimized while ensuring efficient use of lunar materials. Developing effective beneficiation techniques is essential to enabling a scalable and sustainable lunar propellant production infrastructure, supporting long-term space exploration and future interplanetary missions.