Catalytic pyrolysis mechanism of waste R134a/R32 refrigerant mixture over Cu(1 1 1) surface: Density functional theory study

Abstract

The development of degradation treatment technology for waste hydrofluorocarbons (HFCs) was urgent. Copper, a commonly used catalyst, can be used to efficiently catalyze the pyrolysis of pure HFCs, but the catalytic pyrolysis study of HFC mixtures was lacking. In this work, the catalytic pyrolysis of R134a/R32 refrigerant mixture over Cu(1 1 1) surface was studied by using density functional theory method. Four initial catalytic pyrolysis reactions of R134a in adsorbed R134a/R32 mixture and adsorbed R134a, two initial catalytic pyrolysis reactions of R32 in adsorbed R134a/R32 mixture and adsorbed R32 were investigated. The results showed that copper had a better catalytic effect on the pyrolysis of adsorbed R134a/R32 mixture, adsorbed R134a and adsorbed R32. On the Cu(1 1 1) surface, the pyrolysis of R134a was inhibited and the pyrolysis of R32 was improved by the mixture of R134a and R32.