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A new invention that removes one of the most common perfluoroalkyl and polyfluoroalkyl substances from water looks a lot like a stack of frozen waffles (Interesting Engineering).

What’s going on: “Researchers at the University of Bath [in the U.K.] have created ceramic-infused monoliths capable of effectively removing” PFAS from water. “These 3D-printed structures act like magnets for PFAS, capturing and holding onto [the] molecules. In just a few hours, they can remove up to 75%” of PFAS from water.

• PFAS were used widely in everything from clothing to food beginning in the 1940s for their ability to resist corrosion and grease, as well as fight fire.

Why it’s important: In March, citing health concerns, the U.S. Environmental Protection Agency issued the first federal limits on two PFAS chemicals, known as PFOA and PFOS, including near-zero requirements for PFAS in drinking water. More PFAS regulation is expected in the U.S., while the European Union is considering a bloc-wide ban of PFAS.

• The approximately 4-centimeter monoliths are an “efficient way to remove these chemicals from water without using lots of energy,” a Bath Department of Chemical Engineering research associate said.

How it works: A ceramic ink-like material is made using 3D printers and infused with indium oxide, which bonds with PFAS molecules. Next, the monoliths are soaked in PFAS-containing water.

• When the items are removed, the chemicals are removed with them.
• Following use, each monolith gets a 500-degree-Celsius “regeneration” to remove PFAS and ready the device for another round of chemical removal.

What’s next: The researchers will continue to refine the monoliths for improved efficiency and better understanding of the way the technology might be used in water treatment plants.