Researchers from the Universities of Birmingham and Newcastle have developed a simple, mechanochemical method for processing polytetrafluorethylene (PTFE) - most likely to be encountered as Teflon®.
PTFE has a number of useful properties due to the strength of the carbon-flourine bond. However, its durability and chemical resistance make it difficult to process at end of life, leading to an increase in harmful waste, such as PFAS ‘forever chemicals’, and the loss of potentially valuable fluorine. A number of approaches have been proposed for the breakdown of PTFE and reclamation of fluorine, often using harsh chemicals, high temperatures, and large volumes of solvents.
The novel mechanochemical process, in contrast, occurs at room temperature and without solvent, simply milling the PTFE with commercially available sodium metal to produce a mixture of amorphous carbon and sodium fluoride, used in toothpastes.
The process produces sodium fluoride in a high yield and the researchers also demonstrated that the crude material obtained can be used directly in the synthesis of organofluorines.
The open-access publication of this research is available here.
“Our approach is simple, fast, and uses inexpensive materials,” said Dr Lu. “We hope it will inspire further work on reusing other kinds of fluorinated waste and help make the production of vital fluorine-containing compounds more sustainable.”
