化学: 永遠の化学物質の分解

A method for breaking down perfluoroalkyl and polyfluoroalkyl substances (PFASs), environmental contaminants known as ‘forever chemicals’, while recycling the fluoride contained within them is presented in a Nature paper. The process could help address environmental contamination while recovering the fluorine for manufacturing.

PFASs are human-made chemicals that have been frequently used in textiles, firefighting, cookware and medical applications since the 1940s. These chemicals are difficult to break down and have accumulated in the environment, earning them the name forever chemicals. While some methods to break down PFASs do exist, they typically result in the production of smaller PFASs and volatile fluoride-containing compounds that are lost. Recovering fluoride from PFASs could help close the gap in securing this element from critical minerals.

Véronique Gouverneur and colleagues present a method for breaking down PFASs into fluoride compounds using potassium phosphate salts. The authors found that combining Teflon (a common PFAS) with these salts in a steel jar and shaking the mixture at a frequency of 35 cycles per second for 3 hours led to the breakdown of the PFAS. Through further testing, the authors observed that these reactions can break down different types of PFAS used in consumer items. The phosphate salts used in the process can be recovered and reused in subsequent reactions.

The authors note that this method of breaking down PFASs could help to address environmental issues and gaps in certain manufacturing sectors, which may struggle with a lack of fluoride, as well as contribute to a circular economy.