GENOA, Italy, Sept. 21 (UPI) -- Coffee-infused foam sounds like the brainchild of a chef or barista, but it's actually the work of a team of materials scientists and chemical engineers. The foam doesn't go on top of a drink, but it can make water safe to drink -- that is if the water is contaminated with lead.
Previous experiments have shown powder made from spent coffee grounds can extract heavy metal ions from water. But removing the toxic powder from the water isn't easy.
A team of researchers at the Italian Institute of Technology, led by Despina Fragouli, set out to simplify the decontamination process. The scientists created a filter, a combination of spent coffee grounds and bioelastomeric foam.
In initial tests, the foam successfully removed 99 percent of lead and mercury ions from contaminated still water in 30 hours. In flowing water, the foam extracted 67 percent of the lead ions.
"The incorporation of the spent coffee powder in a solid porous support, without compromising its functionality, facilitates the handling and allows the accumulation of the pollutants into the foams enabling their safe disposal," researchers concluded in their paper on the subject, published this week in the journal Sustainable Chemistry and Engineering.
Billions of pounds of spent coffee grounds are generated every year. Some of that waste is recycled as fertilizer, but most finds its way into landfills. The latest technology could help clean contaminated water and lighten the load on trash collectors.