Engineers have developed a system that allows the release of oxygen and hydrogen from salty cold water on Mars. Their research is published in the journal Proceedings of the National Academy of Sciences.
Mars is an icy planet, and the water is full of salt. It is not drinkable, but electrolysis breaks it down into oxygen (for breathing) and hydrogen (for fuel). Removing salt on Mars, however, is cumbersome and costly in harsh and dangerous environments.
But if oxygen and hydrogen are directly extracted from saltwater, the electrolysis process becomes less complicated and expensive. Engineers from the University of Washington in St. Louis have developed a system that will be useful to future colonizers of Mars.
The research team tested their brine electrolysis system in typical Earth conditions and a simulated Martian atmosphere at –36°C.
In the summer of 2008, NASA’s Phoenix Mars “touched and tasted” Martian water. Since then, the Mars Express of the European Space Agency (ESA) has discovered several underground bodies of water. They remain in a liquid state due to magnesium perchlorate’s presence – the magnesium salt of perchloric acid.
To live – even temporarily – on Mars and return to Earth, astronauts will have to produce some of the essentials themselves, on-site, including water and fuel. NASA’s Perseverance rover is equipped with instruments that will use high-temperature electrolysis to transform saltwater. However, this Mars In-Place Oxygen Experiment (MOXIE) can only produce oxygen from carbon dioxide in the air.
The system, developed by engineers at the University of Washington, can produce 25 times more oxygen than MOXIE using the same amount of energy. It also produces hydrogen that can be used as fuel.
The unique design and use of an anode allow the system to operate without heating or cleaning the water source.