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Trifluoromethane is one of the most potent and stable greenhouse gases with global warming potential of 14,800 times higher than CO2 (100-year time horizon). At present, it is destroyed by incineration or plasma at temperatures above 1200 K. For the first time, this work report that CHF3 can be reverted to HCFC-22 via the intermolecular Cl/F exchange reaction of CHF3 with CHCl3 over AlF3 catalyst under moderate conditions. As CHF3 is produced during the manufacture of HCFC-22 via the fluorination of CHCl3 in liquid phase, no additional feedstock and products are involved for the treatment of CHF3 in this proposed process. At 593 K and atmospheric pressure, CHF3 conversion levels of about 18%-20% are achieved and no significant deactivation is observed following time on stream of 100 h. In addition, the catalytic reaction mechanism is proposed. According to the experiments and DFT calculation, the intermolecular Cl/F exchange reaction of CHF3 with CHCl3 is mainly initiated by the breakage of C-Cl. The present work provides a potential resource utilization route for the treatment of CHF3 and other hydrofluorocarbons (HFCs).