The technical objective of this project is to establish and implement state-of-the-art methods for the real-time analysis of products of incomplete destruction (PID) during the thermal treatment of per- and polyfluoroalkyl substances (PFAS). This will in turn be used to elucidate the destruction mechanisms and identify potential surrogates that can be used to track the destruction efficiency of PFAS.

In this project, the project team will use advanced analytical techniques to detect and quantify PID and elucidate the thermal decomposition mechanisms of PFAS, including chemical ionization time-of-flight mass spectrometry (CI-TOF-MS) and real-time Fourier transform infrared spectroscopy. The specific research tasks of this project are as follows:

1. Establish the use of CI-TOF-MS and FTIR for the real-time analysis of PID from the thermal treatment of PFAS.
2. Develop mechanistic pathways for the thermal destruction of PFAS and formation of PID under various conditions, and identify surrogate species that can be used to identify incomplete PFAS combustion.
3. Quantify PID from the thermal treatment of PFAS in a bench-scale, two-stage rotary incinerator under varying conditions.

In Task 1, the project team will establish the use of CI-TOF-MS and FTIR for the real-time detection and quantification of PID (and PFAS) resulting from the thermal treatment of PFAS. In Task 2, the project team will apply these methods to elucidate the mechanisms of thermal destruction for a wide range of PFAS, and the project team will identify potential surrogate compounds to track the destruction efficiency. In Task 3, the project team will apply the real-time analytical methods to quantify PIDs from the thermal treatment of PFAS under varying operating and matrix conditions.

A primary reason for knowledge gaps associated with thermal processes associated with PFAS destruction is the limited sampling and analytical techniques for identifying and quantifying PID. A major deliverable of this project will be the development of methods that can detect PID in real time, which will confirm the quantifiable presence or absence of PID generated during PFAS treatment. Successful implementation of this research holds profound implications for improving the DoD's management of PFAS, directly addressing mission readiness by safeguarding the health of the warfighter and communities. (Anticipated Project Completion - 2028)