A team at Rice University has invented an eco-friendly material that rapidly captures and destroys PFAS, known as forever chemicals, in water sources. The technology outperforms existing methods by capturing pollutants thousands of times more efficiently and regenerating for reuse. Published in Advanced Materials, the breakthrough addresses a persistent global pollution challenge.
Per- and polyfluoroalkyl substances (PFAS), synthetic chemicals introduced in the 1940s, are used in products like Teflon pans, waterproof clothing, and food packaging due to their resistance to heat, grease, and water. However, this durability makes them persistent environmental contaminants, linked to health issues including liver damage, reproductive disorders, immune system disruptions, and certain cancers. Found in water, soil, and air worldwide, PFAS are notoriously difficult to remove and destroy.
Traditional removal methods, such as adsorption using activated carbon or ion-exchange resins, suffer from low efficiency, slow speeds, limited capacity, and the generation of secondary waste. "Current methods for PFAS removal are too slow, inefficient and create secondary waste," said Michael S. Wong, professor at Rice's George R. Brown School of Engineering and Computing.
The new solution centers on a layered double hydroxide (LDH) material composed of copper and aluminum, enhanced with nitrate. Developed by postdoctoral fellow Youngkun Chung under Wong's mentorship, in collaboration with Seoktae Kang from KAIST and Keon-Ham Kim from Pukyung National University, the material adsorbs PFAS over 1,000 times better than alternatives and removes large amounts within minutes—about 100 times faster than commercial carbon filters. Its layered structure with charge imbalances enables rapid and strong binding of PFAS molecules.
Tested effectively in river water, tap water, and wastewater, the LDH performs well in both static and continuous-flow conditions, suggesting applications in municipal and industrial water treatment. To complete the process, the captured PFAS are thermally decomposed using calcium carbonate, destroying more than half without toxic by-products and regenerating the material for reuse. Early tests confirm at least six cycles of capture, destruction, and renewal.
"To my astonishment, this LDH compound captured PFAS more than 1,000 times better than other materials," Chung noted. Wong added, "We are excited by the potential of this one-of-a-kind LDH-based technology to transform how PFAS-contaminated water sources are treated in the near future." The research, supported by funding from Korean and U.S. sources including the National Research Foundation of Korea and Rice institutes, highlights international collaboration in tackling pollution.
This advancement offers a sustainable alternative, combining rapid cleanup with eco-friendly destruction, potentially revolutionizing PFAS remediation efforts globally.
