Fluoroform is the chemical compound with the formula CHF3. It is one of the "haloforms", a class of compounds with the formula CHX3 (X = halogen). Fluoroform is used in diverse niche applications and is produced as a by-product of the manufacture of Teflon. Fluoroform is also generated biologically in small amounts apparently by decarboxylation of trifluoroacetic acid.
|Density (ρ) at -100 °C (liquid)||1.52 g/cm3|
|Density (ρ) at -82.1 °C (liquid)||1.431 g/cm3|
|Density (ρ) at -82.1 °C (gas)||4.57 kg/m3|
|Density (ρ) at 0 °C (gas)||2.86 kg/m3|
|Density (ρ) at 15 °C (gas)||2.99 kg/m3|
|Dipole moment||1.649 D|
|Critical pressure (pc)||4.816 MPa (48.16 bar)|
|Critical temperature (Tc)||25.7 °C (299 K)|
|Critical density (ρc)||7.52 mol/l|
|Compressibility factor (Z)||0.9913|
|Acentric factor (ω)||0.26414|
|Viscosity (η) at 25 °C||14.4 μPa.s (0.0144 cP)|
|Molar specific heat at constant volume (CV)||51.577 J.mol-1.K-1|
|Latent heat of vaporization (lb)||257.91 kJ.kg-1|
As a refrigerant, CHF3 is known as R-23 or HFC-23.
HFC-23 is also used as a replacement for Halon 1301[cfc-13b1] in fire suppression systems as a total flooding gaseous fire suppression agent. It is also used as a low temperature refrigerant (replacement for Chlorotrifluoromethane (cfc-13). It is a byproduct of its manufacture. When used as a fire suppressant, the chemical carries the DuPont trade name, FE-13. CHF3 is recommended for this application because of its low toxicity, its low reactivity, and its high density.
CHF3 is a potent greenhouse gas. The secretariat of the Clean Development Mechanism estimates that a ton of HFC-23 in the atmosphere has the same effect as 11,700 tons of carbon dioxide. The atmospheric lifetime is 260 years. According to researchers, it is the most abundant of hydrofluorocarbons (HFCs). Its usage has been regulated since December 1997 at Kyoto climate conference.
It was first obtained by Meslans in the violent reaction of iodoform with dry silver fluoride in 1894. The reaction was improved by Otto Ruff by substitution of silver fluoride by a mixture of mercury fluoride and calcium fluoride. The exchange reaction works with iodoform and bromoform, and the exchange of the first two halogen atoms by fluorine is vigorous. By changing to a two step process, first forming a bromodifluoro methane in the reaction of antimony trifluoride with bromoform and finishing the reaction with mercury fluoride the first efficient synthesis method was found by Henne.
Two enterprises sign agreement with the World Bank.(NEWSDESK: Trading Conflict)(Jiangsu Meilan Group and Changsu 3F Zhonghao New Chemical Materials Co. Ltd.)(Brief Article)
Jan 06, 2006; Jiangsu Meilan Group and Changsu 3F Zhonghao New Chemical Materials Co., Ltd. signed an agreement on the purchase of carbon...