mikeg123
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Tetrachloroethane to trichloroethylene
Hello,
I'm new here(glad to be here!).
Here's a question for you chemistry experts out there. Is it possible to convert Tetrachloroethylene (aka. Perchloroethylene, perc or dry cleaning
solvent) to trichloroethylene?
I'm thinking maybe a reducing agent such as zinc powder could be used with the Tetrachloroethylene in a boiling flask . The reaction would be cooled
(to prevent a runaway reaction) and the tri-chlor vapor can be taken off and condensed as soon as possible.
Any ideas?
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Dr.Bob
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It might be possible to convert Tetrachloroethane to trichloroethylene via a dehydrohalogenation/dechlorination. But it is not the same question as
converting Tetrachloroethylene (aka. Perchloroethylene, perc or dry cleaning solvent) to trichloroethylene, which is a chlorine to hydrogen swap on an
alkene, which is not as easy. The two have both been used for similar uses as solvents.
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Nicodem
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Thread Moved
22-9-2012 at 02:01 |
mikeg123
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Quote: Originally posted by Dr.Bob  | | It might be possible to convert Tetrachloroethane to trichloroethylene via a dehydrohalogenation/dechlorination. But it is not the same question as
converting Tetrachloroethylene (aka. Perchloroethylene, perc or dry cleaning solvent) to trichloroethylene, which is a chlorine to hydrogen swap on an
alkene, which is not as easy. The two have both been used for similar uses as solvents. |
One Hydrogen is needed, I should have looked at that closer.
The reason I am interest in this is Trichloroethylene is hard to come since it was banned by the Montreal Protocol. I wanted to see if there was a way
to produce a small amount (it was a great solvent) and just see if it can be done.
-Thanks
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kristofvagyok
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| Quote: Originally posted by mikeg123 |
I'm thinking maybe a reducing agent such as zinc powder could be used with the Tetrachloroethylene in a boiling flask . The reaction would be cooled
(to prevent a runaway reaction) and the tri-chlor vapor can be taken off and condensed as soon as possible.
Any ideas? |
Zinc will make first a metalloorganic compound similar to Grignard reagents (here C-Zn-Cl) and it will immediately stole a chlorine from the next
carbon, this is called Beta elimination, so a ZnCl2 will come out and dichloroacetylene will be produced what is khm. highly sensitive and
explosive... So I would not recommend using zinc for this reaction.
Trichloroethylene is toxic as hell (It is a good solvent, it perfectly solves sulfur), it is carcinogen ect. So it is not the best to work with. For
the production of it from terachoroethylene, I would recommend a Pd catalysis reduction where the Pd(0) would coordinate to one of the chlorines and
to the double bond, some hydrogen what is bubbled through would get off the Cl and reduce back the Pd to 0 and if thi would go on 90Celsis, then the
trichloroethylene would distill out.
The problem is: no reference, and this would be just my idea a LOT side reaction could happen. It is not an accident that they didn't produce
trichloroethylene from tetrachloroethylene....
I have a blog where I post my pictures from my work: http://labphoto.tumblr.com/
-Pictures from chemistry, check it out(:
"You can’t become a chemist and expect to live forever." |
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Nicodem
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Trichloroethylene is produced industrially from tetrachloroethylene by HCl elimination, so I don't really understand what the problem in finding the
reference is. Kirk-Othmer certainly has a review on it, and a patent search would also give plenty of processes.
As for adapting the industrial process to the amateur friendly process, well, that is something else altogether.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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mikeg123
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Thanks everyone for their response!
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