Kinetic Modeling of the Thermal Destruction of Perfluorinated Sulfonamides

This study investigates the thermal decomposition of perfluorinated sulfonamides, specifically FMSA and FESA, providing key insights into their reaction mechanisms and kinetics under combustion conditions. A detailed reaction scheme is proposed, outlining the primary decomposition pathways, including HF elimination and SO₂ release, along with the formation of reactive intermediate species such as fluorinated three-membered ring compounds. The lowest-energy pathways for FMSA favor the formation of c-CF₂NHSO₂ and c-CF₂OSONH, while FESA predominantly undergoes SO₂ elimination to form C₂F₅NH₂. The kinetic modeling reveals that complete decomposition of both compounds occurs near 1100 K, with FESA requiring higher temperatures due to greater activation barriers. At moderate temperatures, various fluorinated by-products such as HF, CF₃CFO, CF₂O, CFN, and CF₃CN are formed, whereas HF becomes the sole fluorinated product at elevated temperatures. These findings enhance the understanding of the thermal behavior of fluorinated sulfonamides and support the development of effective thermal treatment strategies for their safe disposal.