SAM4CH - 10-6-2006 at 12:00
Can I prepare hexachloroethane from tetra chloro ethylene (C2Cl4) by bubbling Cl2 gas and hexachloroethane will precipitate?
12AX7 - 10-6-2006 at 12:14
Hmm, I would suspect it would remain in solution for quite a while, but other than that, I see no reason why not. Since you're adding to a double
bond it should be faster than a plain chlorination and not need UV excitation (or else, need a lot more since the reaction doesn't produce Cl
radicals?).
Tim
The_Davster - 10-6-2006 at 12:33
Why would it remain in solution? If you bubble dry Cl2 into tetrachloroethylene, eventually the entire thing will solidify. Use of a solvent like
carbontetrachloride would help, which could then be allowed to evaporate leaving you with the hexachloroethane.
12AX7 - 10-6-2006 at 13:37
Consider that, when you start Cl2, it's 100% C2Cl4 and 0% C2Cl6. Say C2Cl6 is about equally soluble in C2Cl4 (100g/100ml). Then you won't have
anything crystallizing until you're half done, when it becomes supersaturated at 50% C2Cl4, C2Cl6. Past this point, you will have large yields of
crystallization due to the solvent being used up: 25% C2Cl4 only holds a third of the 75% C2Cl6 that is present. If you remove product as it is
produced, your reaction volume drops for the same reason.
CCl4 sounds like a good idea. An excess of C2Cl4 could be used, so the precursor is its own solvent. (What is the solubility of C2Cl6 in C2Cl4
anyway?) Might crystallize by cooling or evaporation (pref. distillation) if it's too soluble as in my example above. Speaking of vapor phase, could
it be done in vapor phase? I'm going to guess it would need a catalyst, or maybe just UV. Could be an interesting route to make it though.
Tim
JohnWW - 10-6-2006 at 16:07
What do you want it for? It would be a good dry-cleaning fluid (for which 1,1,1-trichloroethylene, CCl3CH3, is used commonly), or good for thinning
correcting fluid, and would be less volatile than CCl4.
BromicAcid - 10-6-2006 at 16:24
I bubbled Cl<sub>2</sub> into C<sub>2</sub>Cl<sub>4</sub> and wrote my results in one of the threads here. I used
UV light although its effects and necessity are debatable. The result... A precipitate of crystalline
C<sub>2</sub>Cl6<sub>2</sub> after a night of standing and allowing the C<sub>2</sub>Cl<sub>4</sub> to
evaporate some.
BromicAcid - 12-6-2006 at 09:39
I was watching television the other day and they were talking about water purification methods. One of the methods they covered specifically for the
destruction of bacteria was a UV treatment. They showed the device and I about flipped.
It was like a liebig. Looked exactly like one except it was made of metal. The light slipped into the middle where the product would normally travel
and the water went in the side and out a side arm distant from it just like a normal water jacket. The person on the show said you should never look
at the light because it is extremely powerful UV and the apparatus looked like something straight out of a lab. I believe the inside jacket was some
type of glass, not metal as the tube slid into it. If it were all glass on the inside it would be the perfect at home photochlorinator.
vulture - 16-6-2006 at 12:50
They make UV encasings for pond water treatment...
You'd probably have to reverse engineer the apparatus though to make it solvent resistant.
SAM4CH - 16-6-2006 at 13:36
I read some helpful information but it is not clear, it talk about using ferric chloride
"Hexachloroethane is usually produced commercially by the chlorination of tetrachloroethylene in the
presence of ferric chloride at l00-140°C."
So, what is the best conditions for this, and I bought UV lamp 15W how can I use it in my reactor!!?
SAM4CH - 20-6-2006 at 08:09
Is hexachloroethane high sublimation? I left few grams of this material "from bubble Cl2 into C2Cl4 and let solution to evaporate at room temperature"
for few hours but then I did not find any of that solid material!!!???