Electron beam method converts Teflon waste into reusable gases

Researchers at the National Institutes for Quantum Science and Technology (QST) have developed a method to convert polytetrafluoroethylene (PTFE), better known as Teflon, into gas using electron beam (EB) irradiation. This process promises a lower-energy alternative to traditional PTFE recycling, which typically requires extremely high temperatures.

The team, led by Senior Principal Researcher Dr. Akira Idesaki, found that heating PTFE while irradiating it with an electron beam reduced the energy required for decomposition by half. "By applying heat during irradiation, we were able to reduce the energy required to decompose PTFE by 50% compared to traditional methods," said Dr. Idesaki. "This makes large-scale recycling of fluoropolymers much more viable."

PTFE is a heat-resistant, chemically stable plastic used across industries from electronics to cookware. Its molecular stability also categorizes it as a PFAS, or "forever chemical," making disposal a significant challenge. Standard pyrolysis methods require temperatures between 600 and 1000 degrees Celsius. In contrast, the QST team achieved complete gasification at just 370 degrees Celsius using EB irradiation.

At lower temperatures and radiation doses, decomposition was limited-only 10% of PTFE broke down at 30 degrees Celsius with 5 MGy of radiation. Increasing the temperature to 270 degrees Celsius raised this to 86%, with full decomposition occurring at 370 degrees. The process produced oxidized fluorocarbons and perfluoroalkanes, identified using gas chromatography and mass spectrometry. These gases could be captured and reused in chemical manufacturing.

Infrared and X-ray analysis revealed that the internal crystalline structure of PTFE changed significantly under high-temperature EB treatment, supporting more efficient decomposition. "High-temperature irradiation not only enhances decomposition but also changes the internal structure of PTFE," explained Dr. Hao Yu, first author of the study.

The researchers project that this method could cut recycling energy costs for PTFE by approximately 50%, reducing the current 2.8-4 MWh per ton demand typical of pyrolysis. "We hope this technology will contribute to the safer, cleaner, and more cost-effective recycling of high-performance plastics," added project lead Dr. Yasunari Maekawa.

Research Report:Effects of temperature on the decomposition of PTFE induced by electron beam irradiation