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Fluoroform, or trifluoromethane, is the chemical compound with the formula . It is a hydrofluorocarbon as well as being a part of the , a class of compounds with the formula (X = ) with C3v . Fluoroform is used in diverse applications in organic synthesis. It is not an but is a .


Synthesis
About 20 million kg per year are produced industrially as both a by-product of and precursor to the manufacture of . It is produced by reaction of with HF:

It is also generated biologically in small amounts apparently by of trifluoroacetic acid.Kirschner, E., Chemical and Engineering News 1994, 8.


Historical
Fluoroform was first obtained by in the violent reaction of with dry in 1894. The reaction was improved by by substitution of silver fluoride by a mixture of mercury fluoride and . The exchange reaction works with iodoform and , and the exchange of the first two atoms by fluorine is vigorous. By changing to a two step process, first forming a bromodifluoromethane in the reaction of antimony trifluoride with bromoform and finishing the reaction with mercury fluoride the first efficient synthesis method was found by Henne.


Industrial applications
is used in the [[semiconductor]] industry in [[plasma etching]] of [[silicon oxide]] and [[silicon nitride]]. Known as R-23 or HFC-23, it was also a useful [[refrigerant]], sometimes as a replacement for chlorotrifluoromethane (CFC-13) and is a byproduct of its manufacture.
     

When used as a fire suppressant, the fluoroform carries the trade name, FE-13. is recommended for this application because of its low toxicity, its low reactivity, and its high density. HFC-23 has been used in the past as a replacement for Halon 1301(CFC-13B1) in fire suppression systems as a total flooding gaseous fire suppression agent.


Organic chemistry
Fluoroform is weakly acidic with a pK a = 25–28 and quite inert. Attempted deprotonation results in defluorination to generate and (). Some organocopper and organocadmium compounds have been developed as trifluoromethylation reagents.

Fluoroform is a precursor of the Ruppert-Prakash reagent , which is a source of the nucleophilic anion.Rozen, S.; Hagooly, A. "Fluoroform" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York.


Greenhouse gas
is a potent [[greenhouse gas]]. A ton of HFC-23 in the atmosphere has the same effect as 11,700 tons of carbon dioxide. This equivalency, also called a 100-yr global warming potential, is slightly larger at 14,800 for HFC-23.
     
The atmospheric lifetime is 270 years.

HFC-23 was the most abundant HFC in the global atmosphere until around 2001, when the global mean concentration of HFC-134a (1,1,1,2-tetrafluoroethane), the chemical now used extensively in automobile air conditioners, surpassed those of HFC-23. Global emissions of HFC-23 have in the past been dominated by the inadvertent production and release during the manufacture of the refrigerant HCFC-22 (chlorodifluoromethane).

Substantial decreases in HFC-23 emissions by developed countries were reported from the 1990s to the 2000s: from 6-8 Gg/yr in the 1990s to 2.8 Gg/yr in 2007.

However, research in 2024 strongly indicates that the HFC-23 emission decrease is much less than has been reported and does not meet the internationaly agreed of 2020.

The UNFCCC Clean Development Mechanism provided funding and facilitated the destruction of HFC-23.

Developing countries have become the largest producers of HCFC-23 in recent years according to data compiled by the Ozone Secretariat of the World Meteorological Organization. Profits on Carbon Credits Drive Output of a Harmful Gas August 8, 2012 New York Times Subsidies for a Global Warming Gas Emissions of all HFCs are included in the UNFCCCs Kyoto Protocol. To mitigate its impact, can be destroyed with electric plasma arc technologies or by high temperature incineration.


Additional physical properties
(ρ) at -100 °C (liquid)1.52 g/cm3
(ρ) at -82.1 °C (liquid)1.431 g/cm3
(ρ) at -82.1 °C (gas)4.57 kg/m3
(ρ) at 0 °C (gas)2.86 kg/m3
(ρ) at 15 °C (gas)2.99 kg/m3
Dipole moment1.649 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
(ω)0.26414
(η) at 25 °C14.4 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


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