R22 Refrigerant Gas Difluoromethane, also known as difluoromethane, freon-22, abbreviated as HCFC-22, chemical formula CHClF2, is a hydrochlorofluorocarbon containing hydrogen, colorless gas with a slight sweet smell. Freon is a general term for halogenated derivatives of saturated hydrocarbons (hydrocarbons). It is a class of refrigerants that emerged with the development of the chemical industry in the 1930s. It is mainly used as raw material for preparation of tetrafluoroethylene and refrigerant, spray, pesticide production materials, etc. Difluoro-chloromethane is one of the gases that have a damaging effect on the ozone layer (ODP) and a greenhouse effect (GWP). (The ODP of R22 refrigerant is 0.034, GWP is 1760, and ASHRAE safety level is A1.) According to the Montreal Protocol, it has ceased to be used and produced in developed countries, and can still be produced in developing countries, but its production and use deadline is 2030. Main environmental alternatives :R404A, R410A, R290,…