UC Riverside scientists have developed a new catalyst to remove perchlorate from water on Earth, and make Martian soil suitable for agriculture.
Perchlorate is a negative ion consisting of one chlorine atom bonded to four oxygen atoms that occurs naturally in some soils on Earth, and is especially abundant in Martian soil. It also happens to be a byproduct in some disinfectants and herbicides.
Due to its oxidizing nature, perchlorate is used in solid rocket fuel, fireworks, munitions, airbag initiators for vehicles, matches and signal flares.
And that’s where the goodness ends: On account of its ubiquity in both soil and industrial goods, perchlorate is a common water contaminant that causes certain thyroid disorders.
On Mars, it limits the potential for human settlement as Martian soil is abundant in this ion and that means no agriculture or oxygen-producing plants to sustain human life.
UC Riverside’s Changxu Ren and assistant professor Jinyong Liu have now proposed a simple step to reduce perchlorate in water at ambient pressure and temperature using anaerobic microbes.
Anaerobic microbes use molybdenum in their enzymes to reduce perchlorate and harvest energy in oxygen-starved environments.
“This catalyst is much more active than any other chemical catalyst reported to date and reduces more than 99.99% of the perchlorate into chloride regardless of the initial perchlorate concentration,” says Ren.
Ren and Liu found that by simply mixing a common fertilizer called sodium molybdate, a common organic ligand called bipyridine to bind the molybdenum, and a common hydrogen-activating catalyst called palladium on carbon, they could produce a powerful catalyst that quickly and efficiently breaks down the perchlorate in water using hydrogen gas at room temperature with no combustion involved.
According to the scientists, the new catalyst has proven to reduce perchlorate in a wide concentration range – right from less than 1 milligram per liter to 10 grams per liter.
This makes it suitable for remediating contaminated groundwater, treating heavily contaminated wastewater from explosives manufacturing, and even making the Red Planet open to human life.
Image and content: Naturalpedia/University of California, Riverside