Trifluoroiodomethane
Trifluoroiodomethane, also referred to as trifluoromethyl iodide is a halomethane with the formula CF3I. It is an experimental alternative to Halon 1301 (CBrF3) in unoccupied areas.[1] It would be used as a gaseous fire suppression flooding agent for in-flight aircraft and electronic equipment fires. ChemistryIt is used in the rhodium-catalyzed α-trifluoromethylation of α,β-unsaturated ketones.[2] It can be used as a new generation fire extinguishing agent to replace Halon in fire protection systems.[3] The mechanism of extinguishing fires for CF3I is active and primarily based on interruption of the chain reaction in the combustion area of the flame by so-called "negative" catalytic action.[4] It is also used as an eco-friendly insulation gas to replace SF6 in electrical power industry.[5] In the presence of sunlight or at temperatures above 100 °C it can react with water, forming hazardous by-products such as hydrogen fluoride (HF), hydrogen iodide (HI) and carbonyl fluoride (COF2).[citation needed] Environmental effectsTrifluoroiodomethane contains carbon, fluorine, and iodine atoms. Although iodine is several hundred times more efficient at destroying stratospheric ozone than chlorine, experiments have shown that because the weak C-I bond breaks easily under the influence of water (owing to the electron-attracting fluorine atoms), trifluoroiodomethane has an ozone depleting potential less than one-thousandth that of Halon 1301 (0.008-0.01). Its atmospheric lifetime, at less than 1 month, is less than 1 percent that of Halon 1301, and less even than hydrogen chloride formed from volcanoes. There is, however, still the problem of the C-F bonds absorbing in the atmospheric window.[6] However, the IPCC has calculated the 100-year global warming potential of trifluoroiodomethane to be 0.4 (i.e., 40% of that of CO2).[7] References
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