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Hydrofluorocarbon (HFC) working fluid with high global warming potential are step out of the stage of history due to the intensifying global greenhouse effect. Supercritical water gasification (SCWG), an effective and clean waste disposal method, may have better potential for the conversion of waste HFCs working fluid. ReaxFF reactive molecular dynamic and density functional theory method are used in this work to investigate the SCWG mechanism of HFC-245fa. The results indicate that the main products of HFC-245fa SCWG are high value-added chemicals and fuels such as CO, CO 2 , H 2 , and HF. During the gasification process, almost 100 % of the F atoms in HFC-245fa have the potential to become HF, which means that the SCWG method has a strong defluorination effect. The generation of H 2 molecules is promoted and the formation of CO molecule is inhibited in the presence of H 2 O molecules. More importantly, hydrogen bonds are formed between HFC-245fa and H 2 O molecules, which results in the dissociation of HFC-245fa is improved by the SCWG environment. This work provides an available and environmentally friendly route for the efficient conversion of waste HFCs to fuels. [Display omitted] • Supercritical water gasification method has a better defluorination effect. • Almost 100 % of the F atoms in HFC-245fa have the potential to become HF. • Hydrogen bonds promote the decomposition of HFC-245fa and H 2 O molecules. • HF, H 2 and CO rich products could be selectively produced. [ABSTRACT FROM AUTHOR]

• Supercritical water gasification mechanism of R410A is studied. • Gasification process of R410A in supercritical water is described. • Hydrogen bonds are formed between R125 and H 2 O, and between R125 and R32 molecules. • Hydrogen bonds promote the decomposition of R32 and inhibit the decomposition of R125. • HF, H 2 and CO rich products could be selectively obtained. Harmless treatment and resource utilization of the waste HFC refrigerants have gradually become the focus of attention. As a clean waste resource utilization technology, supercritical water gasification has good potential in converting waste refrigerant into high value-added chemicals and fuels. In this study, the supercritical water gasification mechanism of R410A, and the interaction mechanism between R125 and R32, and between H 2 O and R410A during the gasification process are investigated by using ReaxFF reactive molecular dynamic simulation and density functional theory calculation study. The results show that the main products obtained from the supercritical water gasification of R410A are HF, H 2 , CO and CO 2. More than 90 % of F atoms in R410A can be mineralized to form HF molecules. H 2 and CO are two important syngas products during the supercritical water gasification process. Hydrogen bonds are generated between R125 and H 2 O molecules and between R125 and R32 molecules, which leads to the decomposition of R125 molecules more easily, and the decomposition of R32 molecules more difficult. This work provides a possible way to convert waste HFC refrigerant mixture into high value-added chemicals and syngas. [ABSTRACT FROM AUTHOR]