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Re: The "numbering system" section I was a chemist at the DuPont R&D facility in NJ where the Freons were manufactured. The mathematical system used was to represent the formula as #C, #H, and #F as a three digit number and then subtract 90. So, CCl3F would be represented as 101 which would equate to F-11 after subtracting 90.

(R-11, or CFC-11) 174.96.150.71 (talk) 03:43, 2 November 2011 (UTC)[reply]

The system used in the article with the "plus 1" and "minus 1" results in the same designation, but it seems confusing and would certainly be harder to remember. Dcobranchi (talk) 13:53, 7 May 2010 (UTC)[reply]

CFC vs HCFC[edit]

The introduction states that CFCs contain C, F and Cl. For me it means that they do not contain hydrogen. In this case, however, HCFCs are not a subclass of CFCs (as it is stated in the second sentence), but they are an entirely separate class (without an intersection with CFCs). I do not know which statement is correct, but it should be clarified and the text corrected accordingly. Szaszicska (talk) 17:08, 1 August 2010 (UTC)[reply]

CFCs preceded HCFCs. HCFCs replaced CFCs. HFCs are and will replace HCFCs. it is all due to regulatory phase-outs of these chemicals due to their role in ozone depletion. (Their ODP or Ozone Depletion Potential) CFCs and HCFCs have an ODP or ozone depletion potential, due to their chlorine content, while HFCs contain no chlorine, and have no ODP, or an ODP of 0. — Preceding unsigned comment added by 174.96.150.71 (talk) 03:40, 2 November 2011 (UTC)[reply]
This is an interesting claim as well. If an increase in HFCs has no effect (or zero potential) on ozone depletion, its reduction and its potential effects, then their growth shouldn't be expected to cause any offset in terms of the benefits of reducing ozone-depleting substances. Aside from all government regulations, HFCs are a known super-pollutant and do have a similar effect.

HFCs are super pollutants used in fridges, air conditioners and foam insulation. Thousands of times more potent than carbon dioxide, they could account for 19% of greenhouse gas emissions by 2050 if their manufacture continues unchecked.

— Megan Darby

Unfortunately, in many cases CFCs were replaced by HFCs, which do not damage the ozone layer but are similarly effective at heating up the planet.

— See more at: http://www.rtcc.org/2014/07/15/ozone-layer-treaty-could-tackle-super-polluting-hfcs/#sthash.Ekk0mp1E.dpuf
71.82.112.140 (talk) 15:25, 8 August 2014 (UTC)[reply]

Although Hydrochlorofluorocarbons and HCFC both redirect to the top of the article, one needs to scroll down until Chlorofluorocarbon § Classes of compounds, nomenclature in order to know that it stands for Hydro-chlorofluorocarbons. The lead sentence, however, implicitly excludes Hydro-chlorofluorocarbons from the article. I came to this article from Pentafluoropropane where it says: "Unlike CFC and HCFC...". Because both links point to "Chlorofluorocarbon" it is rather confusing. I think the lead should mention HCFC, as it appears in the article. At least the first instance of HCFC should mention "Hydro-chlorofluorocarbons" (not the case). It would also be helpful to know whether it should be written with a hyphen "Hydro-chlorofluorocarbons" (as in the article) or without a hyphen (as in the redirect Hydrochlorofluorocarbons. Rfassbind – talk 14:45, 17 July 2016 (UTC)[reply]

Seems to me a side effect of the way chemists discuss organic compounds. In diagrams, hydrogens are assumed, and not drawn is. Also, all these compounds are halogenated hydrocarbons, that is, replacing hydrogen atoms with halogen atoms. inside the lab, there is not a big distinction on how many hydrogen atoms are left. But yes, the presence of H helps shorten the atmospheric lifetime, which is important outside the chemistry lab. Gah4 (talk) 22:42, 29 September 2016 (UTC)[reply]

Carbon Dioxide as a coolant?[edit]

... One of the natural refrigerants (along with Ammonia and Carbon Dioxide),...
Can CO2 be used as a refrigerant?! If so how and where has it been done? What are the limitations?
Thanks, פשוט pashute ♫ (talk) 13:56, 24 January 2011 (UTC)[reply]
Found the answer. Co2#Refrigerant פשוט pashute ♫ (talk) 14:15, 24 January 2011 (UTC)[reply]
CO2 is a refrigerant that is in use. It's designation is R-744 174.96.150.71 (talk) 03:33, 2 November 2011 (UTC)— Preceding unsigned comment added by 174.96.150.71 (talk) 03:26, 2 November 2011 (UTC)[reply]
A coolant is not a refrigerant, and a refrigerant is not a coolant 174.96.150.71 (talk) 03:33, 2 November 2011 (UTC)[reply]
I suppose that is right. Coolants are used to transfer heat without a phase change, and only from a warmer place to a cooler one. But yes, CO2 can be used as a refrigerant though phase change, in the way of other refrigerants, from a cool place to a warmer place. Gah4 (talk) 04:54, 15 October 2018 (UTC)[reply]

Ambiguous pronoun[edit]

The opening says " A chlorofluorocarbon (CFC) is an organic compound that contains carbon, chlorine, and fluorine, produced as a volatile derivative of methane and ethane. A common subclass is the hydrochlorofluorocarbons (HCFCs), which contain hydrogen, as well. They are also commonly known by the DuPont trade name Freon." Does the bold 'they' mean that CFC's are also known as Freon, or that HCFC's are? Smash bros master (talk) 01:46, 25 May 2011 (UTC)[reply]

Freon was once a trade name for R-12, or CFC-12. Now, it is used frequently, and incorectly to refer to many refrigerants. The term "freon" is used to refer to refrigerants in the CFC class, But the use of the term"freon" WOULD BE LESS SUITABLE to describe the newer HCFCs or HFCs, although it is often used to describe refrigerants in general, within the trade. this is an incorrect usage of the term FREON 174.96.150.71 (talk) 03:54, 2 November 2011 (UTC) 174.96.150.71 (talk) 03:29, 2 November 2011 (UTC)[reply]
"Freon" is a registered trademark of Dupont.

R-23 replacement? But it is global warming hazard too[edit]

The section with alternative replacements lists replacements for materials that are hazardous for the ozone layer. HFC 23 was listed as such a substitute for bad HCFC refrigerants. However, the article for HCFC 23 lists it as a substantial greenhouse gas contributor. The recommendation is not cited, so I presume the contributor listed it this way due to what I presume to be its negligible effect on the ozone layer. The section following this mentions the global warming hazard. Maybe what is needed in the alternatives section is emphasis on replacement from the POV of ozone dangers, not replacement in view of the totality of environmental risks. I have not researched it, so I don't know the answer. If you are reading this, the listing is still there and a reasonable amount of time has elapsed with no one defending this listing, I recommended modifying or clarifying the section or if an error was made, deleting the entry. J JMesserly (talk) 13:20, 11 May 2012 (UTC)[reply]

Also important is atmospheric lifetime. Some chemicals are oxidized fast enough not to be as big a problem. That said, I don't know specifically about R-23. Gah4 (talk) 04:56, 15 October 2018 (UTC)[reply]

CFCs vs. HFCs[edit]

The article claims that CFCs are being replaced by HFCs, hydrocarbons, and CO2, because CFCs contribute to ozone depletion in the upper atmosphere. This claim implies that HFCs are being used as a solution to the problem of ozone depletion caused by CFCs. However, this is not necessarily the case. It should be noted that:

if HFC growth continues on the current trajectory, the increase in HFC emissions is projected to offset much of the climate benefit achieved by phasing out ozone-depleting substances.

— EPA

71.82.112.140 (talk) 15:03, 8 August 2014 (UTC)[reply]

You say "However, this is not necessarily the case," but your following sentences do not contradict the idea that "HFCs are being used as a solution to the problem of ozone depletion caused by CFCs." Rather, they point out that substituting HFCs for CFCs does not solve the problem of radiative forcing and climate change caused by CFCs. As stated elsewhere on this talk page, maybe this distinction needs to be more clear in the article, but description of the relative effects of CFCs and HFCs on ozone depletion is not wrong.HeyRobbie (talk) 17:23, 28 January 2015 (UTC)[reply]
Ozone depletion is bad for us, but isn't the same as climate change. HCFCs are more reactive, and tend to get taken apart before they get to the ozone layer. Fluorine doesn't cause the same ozone depleting reactions as chlorine and bromine. Gah4 (talk) 23:03, 23 May 2019 (UTC)[reply]

Table sort order[edit]

What order are the entries in the table? I could expect alphabetically, or in increasing boiling point, but it doesn't seem one of those. Gah4 (talk) 22:43, 29 September 2016 (UTC)[reply]

External links modified[edit]

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Concentration in atmosphere[edit]

I recall that approximately twenty years ago the concentration of chlorofuorocarbons in the 'ozone layer' was 3-4 parts per billion, that is 3 to 4 cubic millimetres per thousand cubic kilometres. What is the concentration now? — Preceding unsigned comment added by 1.129.96.19 (talk) 20:22, 2 January 2017 (UTC)[reply]

Your math is out by a factor of 109. Try again. Plantsurfer 20:30, 2 January 2017 (UTC)[reply]

Yeas, thanks for the correction. I have just viewed www.theozonehole.com/cfc.htm that indicates that the chlorofluorocarbon concentration peaked at 500 parts per trillion, that is 5 parts per 10,000,000,000. Hope my maths is good and that I have correctly converted the figure to 5cu.mm per 10,000 cu. Klms. — Preceding unsigned comment added by 1.129.96.19 (talk) 20:49, 2 January 2017 (UTC)[reply]

External links modified[edit]

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The most common representative is dichlorodifluoromethane (R-12 or Freon-12).[edit]

The article says: The most common representative is dichlorodifluoromethane (R-12 or Freon-12). I wonder if this is still true? I am not sure that it ever was, as R-11 and some others are more common in industrial settings. (That is, if weighted by actual weight.) But R134a has been common for many years now, such that, at least for consumer use, it should be more common. Gah4 (talk) 04:59, 15 October 2018 (UTC)[reply]

HCFC[edit]

It seems that HCFC redirects here. I suppose that isn't bad, but I might have thought they deserved their own article. I was about to revert the recent change, but with the redirect, they are needed. Gah4 (talk) 23:06, 23 May 2019 (UTC)[reply]

Unsaturated chlorofluorocarbon[edit]

How about unsaturated chlorofluorocarbons which most are derivatives of alkenes (e.g. ethylene), alkynes (e.g. acetylene), or dienes (e.g. butadiene)? If found, they are often highly toxic as hydrogen cyanide! 2405:9800:BA31:F6:1135:D0BB:5A4E:577 (talk) 02:36, 10 September 2021 (UTC)[reply]

The example would be C3Cl5F (a derivative of propene). That's highly toxic! 2405:9800:BA31:F6:1135:D0BB:5A4E:577 (talk) 02:38, 10 September 2021 (UTC)[reply]
Following the transition to HFCs, Hydrofluoroolefins are the fluorinated alkenes, trademark Opteons, starting to be used as refrigerants, and are non-toxic similar to the fluorinated alkanes. Gah4 (talk) 05:33, 10 September 2021 (UTC)[reply]
That's not true! However, some of the aromatic CFCs are somewhat toxic and carcinogenic, not mentioned here in certain articles like organotin chemistry. Possible that the toxicity of some organotin compounds are comparale to that cyanide. 2405:9800:BA31:F6:1135:D0BB:5A4E:577 (talk) 05:54, 10 September 2021 (UTC)[reply]
2,3,3,3-tetrafluoropropene is being sold as a refrigerant, and should have been well tested for toxicity. It is slightly flammable, and that can be a problem when used in cars. And I suspect that the results of burning it might be toxic. But unburned it seems to be safe. Gah4 (talk) 06:08, 10 September 2021 (UTC)[reply]

Combined?[edit]

Why are CFC and HCFC molecules both described in the same article? 137.59.221.36 (talk)\\~~\\\137.59.221.36 (talk) 10:08, 30 December 2021 (UTC)[reply]

I realize this comment is old, but to answer the question for the person posting or anyone else wondering, the articles are combined because having separate articles for CFCs and HCFCs would result in a lot of repeated information spread between both articles which defeats the purpose of having 2 separate articles. North747 (talk) 13:12, 27 October 2023 (UTC)[reply]
source: https://en.wikipedia.org/wiki/Talk:Chlorofluorocarbon

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