Salty water is impossible to drink and so salt removal is obligatory, notably using methods of breaking water into oxygen and hydrogen, the process is extremely complex and costly. The possibility of obtaining oxygen and hydrogen out of briny water would make the process much easier and cheaper.
The Proceedings of the National Academy of Sciences (PNAS), on Monday published research into a new system, developed by the engineers at Washington University in St. Louis, that can directly coerce the elements out of unusable salty water.
The research team, led by Vijay Ramani, Roma B. and Raymond H. Wittcoff, examined the system both in terrestrial conditions and in a simulated Martian atmosphere of -33 ⁰F (-36 ⁰C).
“Our Martian brine electrolyzer radically changes the logistical calculus of missions to Mars and beyond,” said Ramani. “This technology is equally useful on Earth where it opens up the oceans as a viable oxygen and fuel source.”
This technology will provide an additional pathway to help NASA accomplish its mission of landing humans on Mars by 2033. Perchlorate brine electrolyzers are more efficient than the current state-of-the-art alkaline water electrolyzers under terrestrial conditions that provide a route to use suboptimal input to produce ultrapure hydrogen and oxygen, according to PNAS. The approach lays out a unique pathway to life-support and fuel production for future human missions to Mars.
Future astronauts will need to manufacture water to live on the red planet, as well as the fuel necessary for their trip home. The system developed in Ramani's lab can produce both, without the need for heating or purifying a water source.
"Paradoxically, the dissolved perchlorate in the water, so-called impurities, actually help in an environment like that of Mars," said Shrihari Sankarasubramanian, a research scientist in Ramani's group and a joint author of the paper.
The fact that the new system can work with "sub-optimal", or salty, water can significantly lower the cost of electrolysis devices everywhere, including on Earth.
The Ramani team expects to join forces with NASA to further develop the system and also hope that it will be used to help divers explore uncharted environments in the deep sea. 'Having demonstrated these electrolyzers under demanding Martian conditions, we intend to also deploy them under much milder conditions on Earth to utilize brackish or salt water feeds to produce hydrogen and oxygen, for example through seawater electrolysis', said Pralay Gayen, a research team associate.
In 2019 NASA announced that intended to send astronauts to Mars by 2033. NASA administrator Jim Bridenstine told the House Committee on Science, Space and Technology that the Mars landing could be moved up by moving up the moon landing.
"We need to learn how to live and work in another world. The moon is the best place to prove those capabilities and technologies. The sooner we can achieve that objective, the sooner we can move on to Mars", Bridenstine said on April 2, 2019.