By Jamie Martin
Researchers funded by the U.S. National Science Foundation have developed a reusable sponge that helps clean stormwater by trapping valuable minerals like zinc, copper, and phosphate.
This innovation provides a low-cost and efficient way to both reduce pollution and recover non-renewable resources often lost through agricultural and industrial runoff.
The sponge is made with iron oxide nanoparticles, allowing it to capture specific pollutants from water. Once full, it can release the collected materials when the water's pH changes.
Zinc and copper are flushed out by lowering the pH, while phosphates are released by raising it. This controlled release system makes the sponge reusable over multiple cycles without losing effectiveness.
The research, led by Northwestern University and published in Environmental Science and Technology Water, shows the sponge still works well after five uses. It removes pollutants to untraceable levels, making it ideal for sustainable water treatment.
"The technology can be used as a universal sorbent or 'catch-all,' or it can be tailored to certain groups of contaminants like metals, plastics or nutrients," said Vinayak Dravid, professor and co-author.
Lead researcher Kelly Matuszewski added, “We can't just keep flushing these minerals down the toilet. We need to understand how they interact and find ways to actually utilize them.”
The research team has also launched a startup to commercialize the sponge, supported by NSF's Small Business Innovation Research program. Future plans include studying the impact of biofilms, clogging, and water flow.
This innovation presents a promising future for cleaner water and better resource use in farming and industry.
Photo Credit: usda
Categories: National