NASA
Researchers from The Chinese Universities of Hong Kong, Shenzhen and others have developed a technology for producing water, oxygen and fuel from the lunar soil using only sunlight.
One day, this technology will allow astronauts to stay and travel in space, eliminating their dependence on supplies from Earth. It will also make space missions cheaper and likely create a permanent a station on the Moon.
«We never fully realized what «magic» the lunar soil has. The biggest surprise for us was the tangible success of this integrated approach», — says Lu Wang, senior author of the study.
Astronauts in space need water not only to survive and maintain their water balance. It can also be broken down into hydrogen and oxygen. However, water weighs a lot. According to research, sending just 3.7 liters of water into space costs $83,000. This is a significant expense, given that each astronaut drinks several liters of water every day. For long-duration space missions, delivering water from Earth does not seem feasible at all.
As part of a space mission «Chang’e-5» chinese scientists have confirmed that the lunar regolith contains water hidden in minerals and glass formed as a result of our satellite’s collision with meteorites and other bodies. One of these minerals is ilmenite — a dark, heavy compound of iron, titanium, and oxygen. It not only stores water-related chemicals, but also promotes beneficial chemical reactions when heated.
Previous methods of extracting water from lunar regolith were complicated and required significant energy consumption. The new technology simplifies the process and uses only sunlight. The efficiency is achieved through a photothermal catalysis process.
Researchers use sunlight to heat lunar soil and release water from it in the form of steam. In the same system, the steam mixes with carbon dioxide and converts it into oxygen, hydrogen, and carbon monoxide, which is also used as a component for fuel production.
The experiments were carried out using real lunar soil samples obtained within the framework of the mission «Chang’e-5». In addition, a substance similar to lunar regolith was used. The soil was placed in a sealed chamber with CO2. Using sunlight, the gas and lunar soil were heated to a temperature of 250°C.
«Our results showed that this can be done without additional steps or chemicals. All you need is sunlight, CO2 and moon dust», — Lu Wang emphasized.
According to scientists, CO2, exhaled by astronauts, will be collected at night, when the temperature is so low that the gas freezes. The next day, the trapped CO2 will be used in a sunlight reactor together with lunar soil.
Although laboratory tests look promising, the practical implementation of such a system on the Moon will be a challenge. The composition of lunar regolith varies from place to place, with temperature fluctuations ranging from -173°C at night to 121°C during the day.
In addition, it is unlikely that astronauts will exhale a sufficient amount of CO2. Therefore, additional sources, such as dry ice, will be needed. The efficiency of chemical reactions in laboratory conditions has so far proved to be too low for practical life support of astronauts in space.
Lu Wang and his colleagues note that they need to improve catalyst efficiency, improve heat dissipation, and develop more reliable reactors that can withstand lunar conditions. If successful, this simple solar-powered system could help transform the moon from a dead rock to a supplier for the next era of space exploration.
The results of the study are presented in the journal Joule
Source: ZMEScience
