If there are two things that are essential to human life, they're water and oxygen – neither of which are easily available on the moon. Thanks to a new technique, though, astronauts may someday be able to harvest those elements from lunar soil.
The two-step process was developed by a consortium of scientists from the Polytechnic University of Milan, the European Space Agency, the Italian Space Agency and space systems corporation OHB. It builds upon an existing technique utilized in terrestrial applications, and takes advantage of the fact that approximately 50 percent of the soil in all areas of the moon is made up of minerals such as silicon dioxide and iron oxide, which are in turn composed largely of oxygen.
In a lab setup, the researchers started by heating simulated lunar soil in a furnace – in the presence of hydrogen and methane – to a temperature of about 1,000 ºC (1,832 ºF). Doing so vaporized the soil, causing the oxygen-containing minerals to transition straight from a solid to gaseous state, bypassing the molten phase.
Those gases and the residual methane were then sent to a catalytic converter and a condenser, the latter of which separated out liquid water from the mixture. That water could then be consumed as is, or oxygen could be extracted from it via electrolysis.
Leftover hydrogen and methane can be recycled within the system. There's also a solid byproduct which is rich in silica and metals, that could conceivably be processed further for other uses on moon colonies. And while the process may sound rather complex, it can apparently run on its own.
"Our experiments show that the rig is scalable and can operate in an almost completely self-sustained closed loop, without the need for human intervention and without getting clogged up," says Prof. Michèle Lavagna of the Polytechnic University of Milan.
The team's research is being presented this week via the online Europlanet Science Congress (EPSC) 2021.
Source: Europlanet Society