A refrigerant is a substance used to cause or provide cooling. A CFC (chlorofluorocarbon) refrigerant is a colorless, odorless gas that contains chlorine, fluorine and carbon. In use since the late 1920s, scientists discovered that CFCs were damaging the ozone layer of Earth's atmosphere, and their usage as propellants in aerosol sprays and coolants in refrigerators began to be phased out in the 1980s. All types of CFCs will be completely phased out of industrial use by 2030.
Trichlorofluoromethane, known as CFC-11 or the DuPont trade name Freon-11, is a CFC that was once widely used in the refrigeration industry but was phased out by the Environmental Protection Agency. The EPA classifies CFC-11 as a Class I Ozone-depleting Substance.
Molecular formula CCl2F2 produces dichlorodifluoromethane or CFC-12 (DuPont's brand Freon-12). The most widely used CFC both in aerosol dispensers, such as spray cans and fire extinguishers, and in refrigeration devices, CFC-12 is also set to be completely phased out. Known in the automobile industry as R-12 (Refrigerant-12), this chlorofluorocarbon was used extensively in automobile air conditioning systems prior to 1994. CFC-12 has a lifetime of approximately 100 years.
Trichlorotrifluoroethane or CFC-113 has a lifetime of approximately 85 years. CFC-113, another banned pollutant, was used as a coolant in refrigeration units and air conditioners. The chemical molecular formula for trichlorotrifluoroethane is C2Cl3F3.
Dichlorotetrafluoroethane, or CFC-114 (molecular formula C2Cl2F4), is a pollutant with refrigerant properties. The EPA lists CFC-114 as a Class I Ozone-depleting Substance. It was once used as a coolant in refrigeration units and known as Refrigerant 114 or R-114 in industry terms. CFC-114 has a lifetime of approximately 300 years.
According to the EPA, of all the most common chlorofluorocarbons, monochloropentafluoroethane, or CFC-115, takes the longest amount of time to disappear from the atmosphere. CFC-115 has a lifetime of approximately 1,700 years. Once used as a refrigerant, new usage is banned and existing usage is being replaced. CFC-115 is produced using the chemical molecular formula C2ClF5.
In addition to chlorine, fluorine and carbon, hydro-chlorofluorocarbon (HCFC) contains hydrogen. A number of HCFCs are used in both domestic and industrial refrigeration systems that once used CFCs. Scientists believe HCFCs do less damage to Earth’s atmospheric ozone layer. However, due to the harmful effects, hydro-chlorofluorocarbons are also in the process of being completely phased out.
- "Science 101 Weather"; Trudy E. Bell; 2007
- Environmental Protection Agency: Class I Ozone-depleting Substances
- University of Denver: Fundamental Refrigerant Management
- Photo Credit Planets in the atmosphere Earth image by Photoeyes from Fotolia.com
Types of Home Freon AC
Homes and offices around the world use air conditioning to remove the heat of indoor air. Air conditioners even out the air...