Talk:Carbon tetrachloride

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Exposure limits[edit]

I don't want to get in an edit war on this, so I've left the numbers as typical figures.

It seems to me to make more sense to do this than to add the recommended limits for the UK, India, Japan... etc.

The alternative would be to link to a page of national limits for exposure to this, but I don't think it's worth the effort, especially as the same argument would apply to any dangerous chemical.

Perhaps another approach would be to leave the "typical" figures as per my edit, and put the sources as links at the end? jimfbleak 15:56 13 Jun 2003 (UTC)

Article title[edit]

Reasons for name change: Tetrachloromethane is the IUPAC name, but aside from IUPAC zealots, no one seems to call it that. Google statistics:

carbon tetrachloride: 63,000 tetrachloromethane: 4,310

Additionally, carbon tetrachloride is the primary entry in the Merck index and just about every chemical catalog.

Melting Point[edit]

Just a notice, there are 2 physical properties sections on the page to the left, everything is the same except the melting point. (BTW This is my first comment so please pardon me if this wasnt an error)

Hepatitis?[edit]

Why is this article under the "Hepatitis" Category? I see no relationship. If no one objects, I am going to remove it. Bonus Onus 00:41, Mar 9, 2005 (UTC)

I expect they were confused with "hepatotoxic". -- Securiger 16:08, 16 May 2005 (UTC)

Aerosol propellant?[edit]

Under "Uses", we have:

Carbon tetrachloride persisted as an aerosol propellant and...

Huh? The boiling point at 1 atm is 77ºC. Aerosol propellants need to have a bp lower than STP. Clearly it can't be a propellant, but what was meant here? -- Securiger 16:08, 16 May 2005 (UTC)

I have removed the claim that it was used as an aerosol propellant. It is physically impossible for carbon tetrachloride to serve as an aerosol propellant at STP, and I have found no references hinting at what might have been meant here. I suspect confusion arose from the fact carbon tetrachloride was used in the production of CFCs (some of which were used as aerosol propellants), a fact which is already mentioned in the next paragraph. -- Securiger 05:38, 22 May 2005 (UTC)

Antidepressant? Invented words! Article vandalized?[edit]

I am removing the entire text

Noted MIT researcher Dr. Makhlook Singh has noted that carbon tetrachloride has been observed to create psychedelic behavior in rats exposed to it in low concentrations for a long period of time. Dr. Singh pointed out that it may have useful medical properties if it could be refined and blended with other anti-depressant drugs, such as asycomycotacol or indiamycotacolis. He noted the latter, when blended with carbon tetrachloride, reversed noticeable brain synapse damage through, as he calls it, the Bombay effect. As he says, much research is needed to determine if any long term risks are present in the medical use, but it may radically change the process of treating such disabilities from simple depression to previously-irreversible neurological synapse damage. There is much promise in this research for those affected by neurological disorders.

Upon first reading it seemed to be absurd - but it captured my attention nonetheless because it was so full of improbability Psychedlic carbon tetrachloride! That brings a whole new meaning to disolving mental boundaries! Unfortunately, this proved to be mere vandaliasm, and I have done the following with Google to confirm: Verified that asycomycotacol appears to be a made up word. Verified that indiamycotacolis also appears to be a made up word. Verified that if there even is a Makhlook Singh at MIT or anywhere else, he sure is NOT noted, as claimed. The Bombay Effect also sounds like something out of a hollywood script rather than a researcher.

While the prospect of some college kid getting totally busted turning in a report mentioning any of the text in the vandalism, the prospect of some overinteligent and underwise junior high kid trying it out Zaphraud 22:54, 15 January 2007 (UTC)

Note about name change[edit]

An anon changed the name in the article, and not very elegantly. The edits were before those of User:Carbonferum, who also seems to have copied a picture from the japanese wikipedia in another article. Dunno i Carbonferum and the anon are the same people. I'll fix this later if i remember, and no-one else does :-D. Tristanb 06:00, 25 May 2005 (UTC)

I've reverted. This seems to me to be a clear case of an common name that isn't going anywhere anytime soon.
From the preamble to IUPAC's 1993 nomenclature recommendations:
In contrast to such systematic names, there are traditional names, semisystematic or trivial, which are widely used for a core group of common compounds. Examples are "acetic acid", "benzene", "cholesterol", "styrene", "formaldehyde", "water", "iron". Many of these names are also part of general nonscientific language and are thus not confined to use within the science of chemistry. They are useful, and in many cases indispensable (consider the alternative systematic name for cholesterol, for example). Little is to be gained, and certainly much to be lost, by replacing such names. Therefore, where they meet the requirements of utility and precision, and can be expected to continue to be widely used by chemists and others, they are retained and, for the most part, preferred in this Guide.
When the governing body that recommends a system of nomenclature acknowledges that for some compounds, their systematic name has failed to displace, and insofar as the future is forseeable will continue to fail to displace, the traditional name, and is OK with that, it seems foolish to promote that system of nomenclature more zealously than the governing body itself. Shimmin 11:26, May 25, 2005 (UTC)

Question[edit]

If carbon tetrachloride (CCl4) dissolved in benzene (C6H6) [and it can], would they both still be toxic? Random the Scrambled 12:17, 1 May 2006 (UTC)

Flammability[edit]

At any temperature, Carbon Tet is not flammable at all. So is Chloroform and Dichloromethane.

True, but carbon tetrachloride does decompose on contact with hot surfaces or flames to give, among other products, phosgene: see the ICSC. Physchim62 (talk) 06:57, 18 May 2006 (UTC)

Chloroform and DCM will actually burn when mixed with flammable material, and yes, they produce phosgene and dioxins 134.147.247.12 (talk) 11:36, 5 January 2009 (UTC)

Unverified Claim[edit]

I think it is highly unlikely that Carbon tetrachloride to form phosgene. It would have to be reacted with a phosphorus bearing compound, it would not spontaneously form phosgene as the article and your comment claim. Iepeulas 20:09, 12 September 2007 (UTC)

My bad, I thought phosgene contained phosphorus, it does not. I removed the unverified template. Iepeulas 20:12, 12 September 2007 (UTC)

Carbon tetrachloride does form phosgen at higher temperatures.--Xenofonos 17:26, 1 November 2007 (UTC)
And your reason for saying this is ....?--Smokefoot 23:59, 1 November 2007 (UTC)
Carbon tetrachloride was formerly used in fire extinguishers, and could be exposed to high temperatures when the extinguisher was used. ABehrens (talk) 18:50, 11 June 2010 (UTC)

Ref[edit]

The Involvement of Kupffer Cells in Carbon Tetrachloride Toxicity Edwards M. J., Keller B. J., Kauffman F. C. and Thurman R. G. Toxicology and Applied Pharmacology Volume 119, Issue 2 , April 1993, Pages 275-279 , doi:10.1006/taap.1993.1069 --Stone 10:42, 8 October 2006 (UTC)

The solubility of CT in water appears to be wrong.[edit]

I have found 2 other sources that list the solubility in water as 785 - 800 mg/L and not the 8 mg/L shown in the article. See www.inchem.org/documents/ehc/ehc/ehc208.htm and www.atsdr.cdc.gov/toxprofiles/tp30-p.pdf. Also I work with the Department of Toxic Substances Contol/Cal EPA and one of the carbon tetrachloride contaminated groundwater plumes would have concentrations far in excess of the solubility if 8 mg/L were correct.

John Muegge

205.225.207.186 (talk) 19:46, 9 January 2008 (UTC)

Organic or Inorganic?[edit]

I find the article belongs to the category of Inorganic carbon compounds. As this compound is also a haloalkane, I doubt whether it is organic or inorganic compound. -Quest for Truth (talk) 19:20, 17 February 2008 (UTC)

The decision what compound is organic or inorganic is less hard than it sounds and it is done more of historic reasons and looks at the context. CHCl3 organic and CCl4 inorganic is OK for tha hard criteria of C-H bonds but does not make sense., The compound O=C(NH2)2, O=C(OH)2 are both more inorganic, but the first is counted organic (urea). In the context CCl4 should stay organic!--Stone (talk) 06:46, 18 February 2008 (UTC)
Thank you for Stone's quick reply! So you also think that CCl4 should get out from the list of inorganic compound and we should amend the definition of organic compound? --Quest for Truth (talk) 12:44, 19 February 2008 (UTC)
I don't think the category hurts. Some people consider it organic, some inorganic, because the exact division is a bit fuzzy and arbitrary. It can be in both categories. --Itub (talk) 13:27, 21 February 2008 (UTC)

Production banned?[edit]

Hey, just thought you might want to throw this in the article but I'm having trouble with verification and hoped someone else might have better luck. According to Organic Chemistry 4th Edition by G. Marc Loudon, page 318, production of CCl4 was banned in 1996. I can't find much on it, and Loudon doesn't provide a source, but I'm loathe to believe that verification is impossible. EagleFalconn (talk) 15:49, 18 July 2008 (UTC)

its production appears to be widespread, possibly unavoidable mainly as a byproduct in chlorinolyses. It is not banned so far as I can tell in Ullmann's Encyclopedia of Industrial Chemistry.--Smokefoot (talk) 17:16, 18 July 2008 (UTC)
So then did Loudon perhaps mean that its direct production is banned? It still seems odd as its such a commonly used substance. EagleFalconn (talk) 22:38, 20 July 2008 (UTC)
A good description of the rules in the UK is available at here. CCl4 is regulated under the Montreal Protocol: details here.
Ben (talk) 22:52, 20 July 2008 (UTC)

The first question that popped into my mind when I read this section heading was "where?". It makes no sense to talk of a chemical being banned without specifying where. Some chemicals may be banned in the U.S. but not in China, or they may be banned only for certain uses. CCl4 certainly seems to be "deprecated", but is still available for some uses. --Itub (talk) 16:14, 21 July 2008 (UTC)

Thats the other thing. Loudon doesn't specify where either. It simply says, and I'm quoting, "Production banned in 1996." in a footnote talking about acid base chemistry in different solvents. No details. Loudon is a pretty authoritative organic textbook, it seems odd that something like that would be spuriously introduced. Which is another reason I came to the talk page to see if anyone knew anything about it. EagleFalconn (talk) 13:48, 25 July 2008 (UTC)
It's an introductory textbook, so it is understandable that the author didn't want to get lost in the details about the ban. Now I'm curious too. Here's an indirect clue: Sigma-Aldrich sells carbon tetrachloride [1], but it says "not available in EU". Maybe that means that it is really banned in the EU? --Itub (talk) 14:02, 25 July 2008 (UTC)
This article (doi:10.1006/enfo.2000.0010) has some detail about the bans of CCl4 in the U.S. for various uses, as well as under the Montreal protocol. --Itub (talk) 14:11, 25 July 2008 (UTC)w
Another interesting article, but a bit old: doi:10.1016/0165-9936(95)91368-3. This has the analytical chemistry perspective from 1995. It mentions that the Montreal Protocol has a few exceptions for "essential uses", which includes some laboratory applications. However, the article says that the terms might change in a few years (after 1996), so I don't know what the situation is now. The current Wikipedia article on the Montreal Protocol also mentions the existence of exceptions. --Itub (talk) 14:22, 25 July 2008 (UTC)
Ok, I found the real thing, the actual text of the Montreal Protocol (emphasis added).
Each Party shall ensure that for the twelve-month period commencing on 1 January 1996, and in each twelve-month period thereafter, its calculated level of consumption of the controlled substance in Group II of Annex B does not exceed zero. Each Party producing the substance shall, for the same periods, ensure that its calculated level of production of the substance does not exceed zero. However, in order to satisfy the basic domestic needs of the Parties operating under paragraph 1 of Article 5, its calculated level of production may exceed that limit by up to fifteen per cent of its calculated level of production in 1989. This paragraph will apply save to the extent that the Parties decide to permit the level of production or consumption that is necessary to satisfy uses agreed by them to be essential.
If I read this right, CCl4 is really banned by the protocol, but essential exceptions apply, which is probably why you can still buy small (and expensive!) amounts from Aldrich. --Itub (talk) 14:33, 25 July 2008 (UTC)

'Chlorinolysis'?[edit]

Section 'History and Synthesis', eighth line. The correct prefix for chlorine is chlor(o)-. So it should spell 'chlorolysis'. Besides, to me it's simply combustion (oxidation by chlorine to highest oxidation state), not 'chlorolysis'. Burning ethane breaks it into carbon dioxide(oxidation to highest oxide) and water, is it 'oxolysis' then? Zhieaanm (talk) 01:09, 15 January 2009 (UTC)

Google reveals about 6000 uses of the term. One of which describes "A process termed chlorinolysis (exhaustive chlorination) was applied to..." Merriam-Webster also has a definition but you have to pay to reach it. Rmhermen (talk) 18:04, 13 May 2009 (UTC)

I was a metal machinist in the 1980s. Until it was banned, carbon tetrachloride was applied to the cutting tool while cutting grooves that required very smooth finishes, with a small groove radius. The machine spindle had to be operated at very high RPM to achieve the radial velocity for cutting. The grooves were "plunged", it was an art to do this on a manual machine because the cutting tool could not "rub" at the end of the plunge, else "chatter" would occur marring the groove finish. In effect you had to be fast enough to pull back at the end of the plunge before the spindle made another revolution. Carbon tetrachloride was applied to the cutting surface during the cutting plunge. I do not know the physics behind it, but it produced very good finishes on the metal, and was sorely missed by the machine operators after the ban. 173.25.223.151 (talk) 01:31, 7 August 2011 (UTC)


If you can dig up a written source for this, you should add a bried account of the application to the article.Catsmeat (talk) 10:41, 7 August 2011 (UTC)
Although the story is intriguing, I urge caution about including such info. Many thousands of uses for many common chemicals have been devised over the centuries, and while such apps are often interesting and charming, their notability is debatable and the inclusion of such anecdotes potentially can interfere with readability ("my pappy used xyz to kill ants" type stuff). --Smokefoot (talk) 13:32, 7 August 2011 (UTC)