A fluorine-centered framework for energy-normalized evaluation of PFAS destruction technologies

Destructive treatment is increasingly recognized as an important long-term strategy for managing per- and polyfluoroalkyl substances (PFAS) because it targets irreversible carbon-fluorine (C-F) bond cleavage rather than contaminant transfer or parent-compound disappearance alone. However, comparison of destructive processes remains challenging because defluorination performance and energy demand are not consistently integrated within a common evaluation framework. To address this gap, this study develops an energy-normalized, fluorine-centered framework based on energy-normalized defluorination extent (ENDE) and energy-normalized fluoride production (EFP), which represent fractional defluorination and absolute fluoride production per unit energy input, respectively. Application of the framework to a curated multi-technology dataset of laboratory-scale aqueous PFAS destruction systems revealed substantial variability in energy-normalized defluorination performance. In photocatalytic systems, parent-compound degradation exceeded a median of 99% for several catalyst families, yet ENDE and EFP varied widely. Across technology classes represented in the dataset and at a common 50% defluorination endpoint, electrochemical systems and UV-based advanced reduction processes exhibited higher median ENDE₅₀ and EFP₅₀ values under the reported operating and energy boundaries. Overall, the framework provides a descriptive and diagnostic basis for evaluating energy-normalized C-F bond cleavage across reported PFAS destruction systems and identifying opportunities to improve defluorination performance.