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MUNICH, Germany — Imagine a chemical so persistent that it can remain in the environment for centuries, silently accumulating in our bodies and potentially causing serious health problems. These are PFAS — synthetic chemicals found in everything from raincoats to food packaging — and researchers at the Technical University of Munich (TUM) may have discovered a groundbreaking way to remove them from our drinking water for good.
PFAS, or per- and polyfluoroalkyl substances, have long been a hidden environmental threat. Used to make products water-resistant and non-stick, these “forever chemicals” don’t naturally break down and can build up in human and animal bodies over time, raising significant health concerns.
A multidisciplinary team of TUM researchers has developed an innovative filter material that could revolutionize how we purify water. By creating a special class of metal-organic framework compounds made from zirconium carboxylate, they’ve designed a filter that is not only water-resistant but also highly effective at trapping these stubborn chemicals.
“PFAS pose a constant threat to public health,” says Professor Jörg Drewes, who leads the Urban Water Systems Engineering department, in a media release. “For too long, the negative effects of the chemicals, which, among other things, ensure that rain jackets are waterproof and breathable, have been underestimated. The industry has now started to rethink this, but the legacy of PFAS will continue to affect us for several generations to come.”
What makes this new filter material unique is its adaptable pore sizes and electrostatically charged surface. By carefully designing the molecular structure and combining it with polymers, the researchers significantly improved the filter’s capacity compared to current methods like activated carbon and specialized resins.
The breakthrough published in Advanced Materials wasn’t the work of a single researcher, but a collaborative effort across multiple disciplines. Experts from TUM’s Schools of Natural Sciences, Engineering and Design, and Computation worked together to develop and test the new filters.
“When solving such major challenges, experts from a wide range of disciplines have to work together,” explains Professor Roland Fischer. “You simply can’t get anywhere on your own.”
However, the researchers caution that widespread implementation is still years away. Before the filter can be used in water treatment facilities, further research is needed to develop materials that are not only effective but also sustainable, affordable, and completely safe.
Despite the challenges ahead, this research represents a promising step toward addressing one of our most persistent environmental health challenges. As we continue to uncover the long-term impacts of “forever chemicals,” innovations like this offer hope for cleaner, safer water in the future.
Paper Summary
Methodology
The study developed and tested a new material for removing PFAS (toxic chemicals found in water) using metal-organic frameworks (MOFs). The researchers synthesized a specific MOF called UiO-66 and its modified versions with different coatings to enhance water purification efficiency.
They conducted five types of experiments, including testing how well the materials could remove PFAS at different concentrations, how quickly the process worked, and whether the materials could be reused multiple times. Advanced techniques like spectroscopy and electron microscopy were used to observe the chemical behavior of PFAS during the process.
Key Results
The study found that some MOFs worked much better than others at removing PFAS from water. One type, UiO-66-(F)4, was particularly good at grabbing onto PFAS, especially the most dangerous types, like PFOA and PFOS. This material was effective even at very low PFAS concentrations, which are common in real-world water sources. Another important result was that these materials acted fast — capturing most PFAS within a few minutes. The materials could also be cleaned and reused several times without losing much efficiency.
Study Limitations
While the MOFs showed promise, there were some challenges. Not all types of PFAS were removed equally well; shorter-chain PFAS were harder to capture. The materials also became less effective over time in some cases, especially if they weren’t cleaned properly. Additionally, the process of making and modifying MOFs could be expensive and time-consuming, which might make large-scale use difficult. The study was conducted in a controlled lab setting, so real-world water conditions, like the presence of other contaminants, might affect performance.
Discussion & Takeaways
This study highlights a big step forward in cleaning up PFAS from water using MOFs. The researchers discovered that the surface design of the MOFs is key — how the material interacts with water and PFAS molecules on its surface is more important than its internal structure.
This finding could lead to cheaper and more efficient solutions in the future. By tweaking the surface coatings, they created a reusable system that performed better than current methods like activated carbon. However, scaling this technology up for widespread use will require further research and cost reduction.
Funding & Disclosures
This work was supported by the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement (MSCA-ITN-2018, EJD Nowelties, Grant No. 812880), the Alexander von Humboldt Foundation, Science Foundation Ireland (21/PATH-S/9454), the Deutsche Forschungsgemeinschaft (DFG Priority Program 1928, Project No. 273920491), the TUM Innovation Network ARTEMIS, and the U.S. Department of Energy’s Office of Science (Award No. DE-SC0019902). The Titan Themis TEM experiments were supported by SFI (Grant No. 12/RI/2345/SOF) and the Royal Society of Chemistry (Grant No. R21-1260380525).
The authors thank collaborators and contributors, including Dr. Oliver Knoop, Dr. Ignacio Sottorff Neculhueque, and others for their valuable input. Open access was enabled by Projekt DEAL. The authors declare no conflicts of interest.
