Trichlorofluoromethane

Trichlorofluoromethane, also called freon-11, CFC-11, or R-11, is a chlorofluorocarbon. It is a colorless, faint ethereal, and sweetish-smelling liquid that boils around room temperature.Hemispheric and Global mean concentrations of CFC-11 (NOAA/ESRL)Time-series of atmospheric concentrations of CFC-11 (Walker et al., 2000)'Present day' (1990s) sea surface CFC-11 concentration'Present day' (1990s) CFC-11 oceanic vertical inventory Trichlorofluoromethane, also called freon-11, CFC-11, or R-11, is a chlorofluorocarbon. It is a colorless, faint ethereal, and sweetish-smelling liquid that boils around room temperature. It was the first widely used refrigerant. Because of its high boiling point (compared to most refrigerants), it can be used in systems with a low operating pressure, making the mechanical design of such systems less demanding than that of higher-pressure refrigerants R-12 or R-22. R-11 is assigned an ozone depletion potential of 1.0, and U.S. production was ended on January 1, 1996. Trichlorofluoromethane is used as a reference compound for fluorine-19 NMR studies. Prior to the knowledge of the ozone depletion potential of chlorine in refrigerants and other possible harmful effects on the environment, trichlorofluoromethane was sometimes used as a cleaning/rinsing agent for low-pressure systems. Trichlorofluoromethane was formerly used in the drinking bird novelty, largely because it has a boiling point of 23.77℃ (74.79℉). The replacement, dichloromethane, boiling point 39.6℃ (103.3℉), requires a higher ambient temperature to work. The substance was included in the production moratorium agreed in the Montreal Protocol of 1987. However, in 2018, its atmospheric concentration was noted to be declining more slowly than expected, and it subsequently emerged that it remains in widespread use as a blowing agent for polyurethane foam insulation in the construction industry of China.