https://phys.org/news/2025-11-simple-destroy-pfas-carbon.html
Researchers at Clarkson University have discovered a new way to destroy "forever chemicals," known as PFAS, using only stainless steel ball milling equipment. The method does not need added chemicals, heat, or solvents.
PFAS, or per- and polyfluoroalkyl substances, are a group of man-made chemicals used in products like nonstick pans, firefighting foam and water-resistant clothing. They are called "forever chemicals" because they do not break down easily in the environment and can build up in people, animals and water supplies.
The study, published in Environmental Science & Technology Letters, demonstrates that PFAS adsorbed on granular activated carbon can be completely destroyed by milling the material in a stainless steel ball mill.
"Granular activated carbon is widely used to remove PFAS from water," said Yang Yang, an associate professor of civil and environmental engineering at Clarkson University. "But dealing with used carbon filled with PFAS has become a big problem. Our new process offers a clean and simple way to get rid of these chemicals at room temperature."
Graduate students Jinyuan Zhu, Xiaotian Xu, and Nanyang Yang worked on the project with Yang. The team found that the collision of steel balls during the milling process generates triboelectrons, which facilitate the breakdown of PFAS through reactions with carbon.
The method worked on many types of PFAS found in both lab-made and real-world carbon samples. After treatment, no PFAS release was detected when the samples were tested under conditions similar to a landfill. This suggests the treated carbon may now be safe for disposal, which has been a long-standing challenge.
More information: Jinyuan Zhu et al, Additive-Free Ball Milling in Stainless Steel Mills Enables Destruction of PFAS on Granular Activated Carbon, Environmental Science & Technology Letters (2025). DOI: 10.1021/acs.estlett.5c00976
(Score: 1, Interesting) by Anonymous Coward on Tuesday November 25, @04:24AM (3 children)
Rather than landfill, I wonder if this carbon (with PFAS decomposed) could be useful for another product? For example in carbon filled engineering plastics (often used for bearings), or even as the carbon black used in rubber manufacture to improve physical properties (why rubber tires are black). Lots of people looking at things like this, in hopes of improving the "circular economy" of various materials.
(Score: 1) by khallow on Tuesday November 25, @11:12AM (2 children)
(Score: 3, Informative) by Anonymous Coward on Tuesday November 25, @02:59PM (1 child)
Um, according to tfa, "PFAS adsorbed on granular activated carbon can be completely destroyed by milling the material in a stainless steel ball mill." If true, then there should be no PFAS left.
I guess the next question has to be, what are the decomposition products, are there there still Florine compounds that are nasty, or are they simple salts (for example) that are not so nasty?
(Score: 1) by khallow on Wednesday November 26, @02:48AM
Glancing at your earlier post, I see that you discuss manufacturing processes that would use already ground PFAS-containing carbon. So the captured PFAS would already be broken down before use of the material. I was thinking more that the material was inserted into a product (say some sort of consumer product) and ground there.
(Score: 2) by Beryllium Sphere (r) on Tuesday November 25, @11:15PM (1 child)
Do you get other fluorine compounds, or loose fluoride ions? There could definitely be a toxicity and disposal problem.
(Score: 1, Touché) by Anonymous Coward on Wednesday November 26, @02:07AM
Ha, coming from "Beryllium Sphere", I'd think you know all about toxicity!
Ref: https://fluoridealert.org/studies/beryllium/ [fluoridealert.org]
"Of all beryllium compounds, beryllium fluoride complexes (including beryllium fluoride and beryllium oxyfluoride) appear to be the most toxic."