Researchers Clean Up Contaminated Groundwater
“A site treated with ferrate, will go from toxic to less toxic, and from less toxic to non-toxic.” – Yang Deng.
Nearly half of the drinking water flowing from taps in the United States comes from wells so what’s in it is vitally important to the health of those who drink it. Yet groundwater supplies have been contaminated by chemicals, heavy metals and other toxins, primarily through the improper storage or disposal of industrial chemical waste.
Researchers at Montclair State have received a grant from DuPont for a 2 ½-year study to develop a new groundwater remediation method
Developing new, innovative and environmentally sustainable, “green” solutions to contamination problems is a specialty for Dibyendu Sarkar, professor of earth and environmental studies and director of the doctoral program in environmental management, and fellow researchers Yang Deng, a professor with the Department of Earth and Environmental Studies, and post-doctoral fellow, Sudipta Rakshit.
Together, the three proposed a study to use ferrate(VI), a form of iron, to treat groundwater contaminated with Freon®. Ferrate is used to treat drinking and wastewater but applying it to groundwater remediation is new. “We knew that there were many other oxidants that people were using quite frequently but no one was using ferrate,” says Sarkar.
Ferrate is a powerful oxidizer that breaks down toxic compounds and eventually becomes harmless rust. “A site treated with ferrate, will go from toxic to less toxic, and from less toxic to non-toxic,” explains Deng. “After oxidation, it becomes iron rust and rust is an excellent adsorbent to adsorb heavy metals such as arsenic or mercury, effectively removing them from the groundwater.”
Ferrate is also environmentally friendly, sustainable and fast acting. “Iron is the fourth most common element in the earth’s crust,” notes Deng. “It’s non-toxic so we can use it anytime, anywhere.” And thanks to a ten-fold reduction in the price of ferrate(VI) in recent years, the team’s proposal is cost effective compared with traditional remediation methods. “That’s when we decided that it could be a suitable candidate for industrial-scale use,” says Sarkar. “We’ve done preliminary studies, and we are confident that this is going to work.”