hippo
Harmless
Posts: 26
Registered: 24-8-2016
Member Is Offline
Mood: No Mood
|
|
carbon tetrachloride from NaClO and (?)Surfactants
While reading about carbon tetrachloride on Wikipedia, I stumbled across this:
| Quote: |
In 2008, a study of common cleaning products found the presence of carbon tetrachloride in "very high concentrations" (up to 101 mg/m3) as a result of
manufacturers' mixing of surfactants or soap with sodium hypochlorite (bleach).
|
Now, put me on detritus for saying this or whatever, but if we found out what the surfactants in question were, could we use this to our advantage to
develop a more OTC way of producing carbon tet?
|
|
|
wg48
National Hazard
Posts: 821
Registered: 21-11-2015
Member Is Offline
Mood: No Mood
|
|
"very high concentrations" (up to 101 mg/m3) or about 0.1 ppm Thats a meaning of very high concentrations I have not encountered before LOL You would
get more radium from precessing a metric ton of uranium ore.
|
|
|
hippo
Harmless
Posts: 26
Registered: 24-8-2016
Member Is Offline
Mood: No Mood
|
|
I mean to say if the reactants were in large quantities
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
Apart from what wg48 said, it's very unlikely. Hypochlorite is one of the strongest oxydants known but it's a very poor chlorinating agent.
The carbon tet must have been present in one of the product's raw materials.
|
|
|
byko3y
National Hazard
Posts: 721
Registered: 16-3-2015
Member Is Offline
Mood: dooM
|
|
First of all, CCl4 is not the most pleasant thing to work with, thus its value for amateur chemist is not high.
Second, CCl4 can be made from CHCl3 or CH2Cl2 by any free radical chlorination. For this reason chloroform can be used for free radical chlorination -
you will end up with CCl4 anyway, just harder to control the stechiometry.
|
|
|
wg48
National Hazard
Posts: 821
Registered: 21-11-2015
Member Is Offline
Mood: No Mood
|
|
Assuming its not an impurity increasing the concentration of the reactants may well increase the yield, but you would need to increase the yield
by a million fold to only reach just 10%. Even if the yield was proportional product of two concentrations thats still an increase of each of 1000
and the manufactures are unlikely to be using ingredients that have significant reactions with each other because it wastes the ingredients. Of cause
you may hope to find more productive conditions or a suitable catalyst. Not very OTC yet if ever I think.
|
|
|
Texium
|
Thread Moved
3-9-2016 at 15:01 |
AJKOER
Radically Dubious
Posts: 3026
Registered: 7-5-2011
Member Is Offline
Mood: No Mood
|
|
The exposure of the NaOCl to air/CO2, assuming not a lot of NaOH added to slow down decomposiition (cheaper brands of chlorine bleach more likely),
makes HOCl. The latter produces a smell of Cl2O.
I noticed in the last few years a trend to add fragrances and less-splash compounds to chlorine bleach.
I would not expect HOCl/Cl2O to mix well with such organics with aging producing a range of cancerous/toxic products in very small amounts.
I am shocked that possible concerns are now being voiced and not waiting for a fossil record to prove to be statistically significant.
Or is it the chlorine-free bleach industry blowing the whistle to mute the popularity of these newer products? That is more likely.
[Edit] As to the precise chemical origins of CCl4, the HOCl can form an organic chloride in the presence of hydroxyl radicals via the sequence:
·OH + RH → R· + H2O
R· + HOCl → RCl + ·OH
HOCl + uv → ·OH + ·Cl (see https://www.researchgate.net/publication/233272746_Advanced_... )
where sunlight or trace amounts of transition metal impurities in the presence of HOCl could have produced the hydroxyl radicals. The latter can
eventually extract all hydrogen leaving CCl4.
With respect to the transition metal path, per one of my prior comment on SM at https://www.sciencemadness.org/whisper/viewthread.php?tid=63... ) a particularly interesting path is based on a Fenton-type reaction where H2O2
is supplanted, for example, by HOCl, which occurs in biological systems. As a source, see "Fenton chemistry in biology and medicine*" by Josef
Prousek, reaction [15] on page 2,330, to quote:
"For Fe(II) and Cu(I), this situation can be generally depicted as follows [20,39],
Fe2+/Cu+ + HOX → Fe3+/Cu2+ + HO• + X- (15)
where X = Cl, ONO, and SCN. "
[Edited on 7-9-2016 by AJKOER]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
