A prototype oxygen plant has been set up in the European Space Research and Technology Centre (ESTEC) based in Noordwijk in the Netherlands. Using actual moondust and a method developed by the UK company Metalysis for commercial metal and alloy production, the ESA is on the way to create oxygen and rocket fuel. To start and, then, preserve life on the Moon, from the perspective of the future lunar colonization, the two elements are vital.
The samples returned from the lunar surface confirm that the most abundant element of lunar regolith is made up of 40–45% percent oxygen by weight. But this oxygen is bound up chemically as oxides in the form of minerals or glass, so it is unavailable for immediate use. The method used to extract the oxygen is called molten salt electrolysis.
ESA Plans to Turn Moondust Into Oxygen to Help the Future Lunar Colonization Process
At Metalysis, the reactors were not designed to withstand oxygen gas itself, as oxygen produced by the process is an unwanted by-product for them. So, they redesign it to be able to have the oxygen available to measure. The regolith (moondust) is placed in a metal basket, with molten calcium chloride salt, and heated to 950°C. A current is passed through it, which causes the oxygen to be extracted from the solid regolith. Then, the oxygen migrates across the salt, to be collected. For now, the oxygen is vented into an exhaust pipe, but it will be stored after future upgrades of the system.
This process also converts the regolith into usable metal alloys, which will be used to construct habitats or repair vehicles. The ESA’s researchers are designing a version of this system that could be fled to the Moon, to be operated there. By mid-2020’, NASA plans to have a pilot plant on the Moon, to fulfill its ultimate goal: a sustained human presence on the Moon and, maybe one day, Mars.