• 2 min read
German team speeds PFAS breakdown in water
Researchers at HZDR tested two faster ways to destroy PFAS in water: hydrodynamic cavitation and cold atmospheric plasma.
Image: ITzine
German researchers have demonstrated two methods that speed up the breakdown of PFAS, the persistent synthetic compounds often called “forever chemicals.” In laboratory tests, a team at HZDR decomposed these substances in water using hydrodynamic cavitation and cold atmospheric plasma.
PFAS have drawn intense scrutiny because they accumulate in water and soil and have been linked to health risks ranging from immune system disruption to a possible increase in cancer. The compounds are widely used in nonstick coatings, fire-resistant materials, packaging, and textiles, and they break down very slowly in the environment.
That has made cleanup technology more urgent as regulation tightens. In 2024, the US Environmental Protection Agency set strict limits for several PFAS in drinking water for the first time, while the European Union is discussing a broader ban on producing and using the chemicals.
Recommended reading
Too Much Power Could Make Electricity Prices Go Negative
How the PFAS cleanup methods work
The first approach relies on hydrodynamic cavitation. Contaminated water is pushed through a constriction, creating microbubbles that collapse and generate localized extreme temperatures and chemically reactive particles. Those conditions accelerate the destruction of PFAS molecules, including one of the group’s most persistent members, perfluorooctane sulfonate (PFOS).
The second method uses cold atmospheric plasma. Gas is fed into the water, and the resulting bubbles carry PFAS to the surface, where the compounds are attacked by the plasma. According to the researchers, this approach works faster than cavitation and does not require catalysts or additional reagents.
Both methods still have limitations. Cavitation currently delivers only partial degradation, while plasma treatment requires significantly more energy and can leave behind byproducts that still need separate analysis.
In lab tests, plasma converted about 35% of fluorine atoms from PFAS into fluoride salts and almost completely destroyed both long-chain and short-chain compounds. For cavitation, the team has set tougher goals: destroying more than 80% of PFAS and mineralizing more than 50% of the bound fluorine.
The researchers are now scaling experiments from 50 ml to 5 l and plan to combine both methods in a single system, using plasma for high reactivity and cavitation to intensify pollutant breakdown. Compared with existing PFAS treatment options such as activated carbon sorbents, membranes, and high-temperature incineration, the work stands out because many current methods mainly move contamination from one medium to another instead of fully destroying the molecules.
Frontier Editor
Dan is our resident futurist, covering electric mobility, space exploration, and the smart home. He's interested in atoms just as much as bits. Whether it's a new battery chemistry, a reusable rocket, or a protocol that finally makes IoT devices talk to each other, Dan breaks down the engineering that pushes humanity forward.
via ITzine
