Fluorinated gases

The fluorinated gases belong to the category of fluorocarbures (FC) and can be gathered in 5 common categories:

• the chlorofluorocarbons (CFC)

• the hydrochlorofluorocarbures (HCFC)
• the hydrofluorocarbures (HFC)
• the perfluorocarbures (PFC)
• the hexafluoride of sulfur ({{chemical formula|SF|6}})

There exist also certain other categories of fluorinated gases, like bromofluorocarbures, the fluorinated ethers and the nitrogen trifluoride (), these last being less present on the environmental level.

Except for Chloride methyl () of marine origin, all the gases of these 5 categories are of synthetic origin. The latter act like gas with greenhouse effect (GES) and thus take part in the climate warming of planet. Although these gases are emitted only in minor amounts (< 2% of the GES in Canada), they have very good life expectancies in the atmosphere, so that their potential of global warming (PRP - 100 years) is very high. These gases thus have a durable effect in the atmosphere and their accumulation causes much interest near the environmental groups.

The use of CFC and the HCFC was banished at the time of the Protocole of Montreal (1987) because of the fact that the latter had a harmful effect on the reduction of ozone the Couche. The radiation of these gases by the rays Ultraviolet S in the atmosphere releases from the ridicalizing Chlore , this last catalyzing the decomposition of ozone () in dioxygene ().

Since the chlorine atoms present in CFC and the HCFC are responsible for the destroying effect on the layer of ozone, the latter were replaced mainly by HFC, of made up containing only atoms of carbon, fluorine and hydrogen (without chlorine). The HFC were practically not used before the application of the Protocole of Montreal and their use wants to be a good alternative compared to CFC. From the fact that they do not contain a chlorine atom, the PFC and are to it them also nondangerous for the layer of ozone.

A reduction in the emissions of PFC and of was observed a little everywhere in the world between 1990 and 2004 (- 53% in Canada and -47% in France for the PFC; -40% to Canada and -34% in France for). An increase in the emissions of HFC however is observed (not quantified in Canada and estimated at +206% in France). This clear increase is due to the fact that HFC were practically not used before the Protocole of Montreal (1987) and that the majority of the applications using CFC and HCFC turned to HFC like gas of replacements.

The CFC emissions are today prohibited and thus very strongly reduced, but their lifespan in the atmosphere (varying from 60 to 110 years according to the compounds) made so that the latter will continue to act like GES for still a certain time. Lastly, the emissions of HCFC are at present in clear fall and their prohibition is gradually application according to the Protocole of Montreal. In Canada, one estimates that in 2010 the emissions of HCFC will be decreased by 65% compared to those of 1996, decreased by 90% in 2015, of 99.5% in 2020 and finally completely prohibited in 2030.

In addition to the Protocol of Montreal, various solutions were proposed to decrease the emissions of fluorinated gases. The Protocole of Kyoto proposes a reduction of the emissions of GES of 5.2% on a worldwide scale in 2012 compared to the levels recorded in 1990, which implies inter alia reductions of 6% for Canada, of 7% for the United States, 8% for the European Union and 6% for Japan. Although the fluorinated gases belong to the 6 types of gases aimed by the Protocole of Kyoto (it, it, it, HFC, PFC and it), this last does not present any concrete standard as for the regulation of fluorinated gases in particular.

It is important to realize that the fluorinated gases aimed by the Protocole of Kyoto and by the various organizations of environmental protection should not necessarily be managed according to the same standards and quotas only it and others GES emitted in greater quantities. The fluorinated gases are produced for specific uses and the majority of them do not present any alternative or alternative, so that it would not be relevant to force to restrict without reserve their emissions as in fact the case for is produced to him in several vast domains and presents several alternatives. Moreover, the fluorinated gases used in the industry of the cold offer an impressive energy efficiency, at such a point where the emission of the latter in the atmosphere can be very well compensated by the reduction of consumption of energy which they generate.

The European Union as for it emitted a concrete plan of regulation on fluorinated gases. The payment was adopted in May 2006 and can be consulted here. The European Union thus imposes certain standards on it aiming at reducing the emissions of certain fluorinated GES. The adopted measures aim overall at ensuring a better containment of fluorinated gases like banishing certain specific applications of these fluorinated gases. Containment includes inter alia the need for taking all measurements technically and economically possible to prevent or reduce to the maximum the escapes of these gases in the apparatuses using them, to ensure a maximum sealing of these apparatuses, that the systems containing more than 3 kg of fluorinated gases are registers and that those containing more than 300 kg of fluorinated gases are equipped with systems of detection of the escapes. The other measurements brought by this payment include in particular the obligatory labelling of the equipment and the products containing of fluorinated gases, a better staff training handling this equipment, of the standards of recovery when possible thus that the installation of a register supervising the fluorinated gas users. Lastly, certain restrictions of use and marketing are or will be installation for certain applications of fluorinated gases, in particular the prohibition of for the filling of the automobile tires (July 2007) like for die casting of magnesium (January 2008).

Nomenclature

This model of nomenclature can apply for any fluorocarbure (FC) of the type CFC, HCFC, HFC and PFC.

The nomenclature of fluorinated gases follows the model of the XYZ-c0123b4a type, where each figure and letters represent:

XYZ: FC, CFC, HCFC, HFC or PFC.

C: Cyclic compound.

0: Many double linkings (omitted if zero). 1: Many carbon atoms - 1 (omitted if zero).

2: Many atoms of hydrogen + 1. 3: Many fluorine atoms.

b4: Many chlorine atoms replaced by bromine atoms (omitted if zero).

a: Letter added to identify isomers.