Synergy of Nonthermal Plasma and Catalysts in the Decomposition of Hydrofluorocarbons

Abstract

This chapter presents the synergy of nonthermal plasma and the different types of catalysts in the decomposition of Hydrofluorocarbons (HFCs)—such as, HFC-23, HFC-32, HFC-134a, and HFC-125. The action mechanisms of the catalysts relevant to the synergy of nonthermal plasma and catalysts are discussed. HFCs have been widely used as the substitutes of perfluorocarbons and hydrochlorofluorocarbons for refrigerants, and foaming agents. Highly efficient technologies for a decomposition of these compounds are urgently required because of their large global warming potentials. Nonthermal plasma has been applied to the decomposition of fluorinated hydrocarbons because it can be facilely operated at ambient temperature. The performances of dielectric-barrier discharge plasma reactors—such as, silent discharge, surface discharge, and ferroelectric packed-bed reactors—are evaluated. In the decomposition of hydrofluorocarbons—such as, HFC-32 and HFC-23—with silent discharge plasma or surface discharge plasma, MnO2, TiO2-SiO2, and A1PO4 show catalytic effects. MnO2 and TiO2-SiO2 promote the oxidative decomposition of hydrofluorocarbons in the presence of gaseous oxygen, while A1PO4 in nonthermal plasma promotes the cleavage of C-F bonds in them.