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Abstract: The destruction of hexafluoroethane (C₂F₆), also known as R-116, was investigated in a nonthermal plasma reactor packed with dielectric pellets. The effects of the feed gas composition and the input power on the destruction of C₂F₆ were examined. The feed gas composition was varied by changing the oxygen content, the argon content and the initial C₂F₆ concentration. An increased input power led to increased C₂F₆ destruction as a result of promoting the electron-molecule collisions to dissociate C₂F₆ molecules. The addition of argon to the feed gas greatly improved the C₂F₆ destruction by reducing the energy losses due to vibrational excitation and dissociation of N₂ molecules, while the increases in the oxygen content and the initial C₂F₆ concentration decreased the destruction efficiency. The byproducts including CO₂, CO, COF₂, CF₄, SiF₄, NO₂, and N₂O were identified, and the destruction mechanisms were elucidated, referring to these compounds. The most abundant byproduct was found to be carbonyl fluoride (COF₂), indicating that it serves as an important medium to convert C₂F₆ into CO₂. The energy requirement for the C₂F₆ destruction was in the range of 8.2–45.3 MJ/g, depending on the initial concentration.

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