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Per
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Ethylchloride preparation
I want to make some C2H5Cl, I know a praparation for it but in this preparation you need ZnCl2, but I haven´t any yet.
My question is, if I can make it also by just introduce HCl gas in C2H5OH with following destillation of the C2H5Cl?
Have anybody any ideas to make the yield higher, for example, is it good to add 98% sulfuric acid to the C2H5OH?
My english is not the best, when I made a big mistake, please tell me
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12AX7
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For sure, you have to be careful about not making ethylene or diethyl ether, two common products of EtOH + H2SO4 + heat.
In terms of esterification it should work, but I think there's a reason why it doesn't.
If you're going to "introduce HCl gas" and need ZnCl2, why not add zinc shavings while adding HCl?
Tim
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Per
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| Quote: | Originally posted by 12AX7
For sure, you have to be careful about not making ethylene or diethyl ether, two common products of EtOH + H2SO4 + heat.
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Yes your right, but preparation of ether needs 140°C and distillation of EtCl needs only 12°C. So I don´t think that EtOh and H2SO4 wuold react.
I don´t even have any Zink here, not the metal and no compound.
[Bearbeitet am 26-1-2007 von Per]
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12AX7
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Say what?
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Per
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I´m new here and I made a little mistake, but I edited already.
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Nicodem
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Unlike the hydrobromic or hydroiodic acids, the hydrochloric acid is not acidic enough to protonate ethanol efficiently enough for the nucleophilic
substitution to occur at a practically useful rate. ZnCl2, which is a strong acid itself, also complexes with HCl to form an even stronger acid.
Additionally ZnCl2 increases the concentration of chloride anions in the reaction mixture. Both effects contribute in a way to increase the rate of
the reaction very much, so ZnCl2 catalyst is necessary.
I can't believe you can not obtain such a common metal as zinc!
The only way to avoid using a Lewis acid catalyst would be to heat a saturated solution of HCl in ethanol to above 100°C in order to increase the
reaction rate. Needles to say that you would need a pressure resistant vessel (10 bar at least).
Also, please use the search engine before posting old questions:
http://sciencemadness.org/talk/viewthread.php?tid=6617#pid75...
…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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Ozone
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I have gotten significant yields of diethyl ether from ethanol catalyzed with H2SO4 sealed and heated to ~105°C for about 4hr. This can significantly
lower ester yields as the ether formation is competitive.
For some real fun, try to store your ethyl chloride in an Al° vessel .
O3
-Anyone who never made a mistake never tried anything new.
--Albert Einstein
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garage chemist
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Even Isopropyl chloride, which is significantly easier to form than ethyl chloride because secondary alcohols are esterified much easier than primary
alcohols, requires ZnCl2 in its preparation (though much less than with ethyl chloride, about 0,1 mol ZnCl2 for 1 mol Isopropanol and 1,5 mol HCl is
enough if distilled very slowly through a column).
So with ethanol, no chance to go without it.
You have to order or make ZnCl2 before you can make ethyl chloride.
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guy
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Is there a reason why zinc chloride is used as opposed to ferric chloride? Is it just more cost efficient?
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garage chemist
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Only the hexahydrate is cheap and available, the necessary anhydrous substance (only this has the required lewis acid activity) is a nasty fuming
solid that reacts vigorously with water, like AlCl3. It can also only be made from the elements or from anhydrous HCl, not from the hydrate. Therefore
it can not be recycled.
Also, I think it gets inactivated in water like AlCl3 due to the formation of the iron(III)hexaaquo complex.
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guy
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You can make anhydrous zinc chloride from the hydrate? I didnt know that, I thought it would form an oxychloride. I guess that is good news then.
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Per
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It´s possible to make dry ZnCl2 when you heat the hydrate and sublimate it following.
But be careful, when you heat it too strong it would envolve HCl gas and the solution would get brown.
I havent any zinc yet because the tubes I can buy have just a small zinc coat.
So I have to buy some ZnO from a chemical shopp.
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Sauron
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As previously reported on this forum (see Search) alkyl chlorides are readily formed from alcohols by the action of cyanuric chloride (CC) also known
as 1,3,5-trichloro-s-triazine (TCT) which is a cheap agrochemical intermediate and totally unregulated.
The journal articles on this have been posted before.
The ethanol should be anhydrous, otherwase you waste some reagent.
You will need very efficient cooling to condense the EtCl. Ice-salt or dry-ice-acetone.
This is a much easier and better prep than mucking around with ZnCl2.
NB do not confuse TCT with TCCA (trichloroisocyanuric acid.) In the former the chlorines are attached to carbon, in the latter, they are attached to
nitrogen.
[Edited on 27-1-2007 by Sauron]
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garage chemist
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Unfortunately Cyanuric chloride is labeled as "Very toxic" (T+) in europe, which makes it damn hard to get and also expensive because one has to buy
from the overpriced chemical suppliers through e.g. pharmacies.
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Per
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[img]For some real fun, try to store your ethyl chloride in an Al° vessel.[img]
I don´t know what happened then but I can imagine
Follows should also be fun:
NaNO3 + C2H5Cl > NaCl + C2H5NO3
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Sauron
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@GC, how unfortunate.
The CC i buy comes from Europe but fortunately in Thailand it is not at all restricted. What about in Switzerland?
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Ozone
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3 Me-Cl + Al° --> AlCl3 + Me3Al.
A supplier screwed up and sent us 3 10kg tanks of MeCl. The problem was that the tanks were Al, rather than stainless as prescribed. This was
determined when a tank was opened and immediately became a flame-thrower. Fortunately, at the time, I was given the option of disposing of the
material. It was around new years, and a pigtail was affixed (to the tank) with
*amazing* results.
TCCA is OTC here as pool chlorinating tablets; it seems like they work fine as-is, but are rather difficult/noxious to powder.
-Anyone who never made a mistake never tried anything new.
--Albert Einstein
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12AX7
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Odd, I've used zinc chloride as flux before. It seems to boil a lot (being a fully liquid solution), then fuse to a sort of glassy material, which I
suppose is zinc chloride plus oxides and impurities (especially iron oxide, being what I was soldering).
Tim
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Nicodem
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| Quote: | Originally posted by Per
Follows should also be fun:
NaNO3 + C2H5Cl > NaCl + C2H5NO3 |
You can not obtain ethyl nitrate this way. The nitrate anions are not nucleophilic enough for such an reaction to occur in practice. If it is ethyl
nitrate that you want than just esterify ethanol with nitric acid. I'm quite sure there are a lot of posts about such esterifications on this forum,
especially in the "Energetic Materials" section (just UTFSE).
…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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chemrox
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Can the Lewis acid, ZnCl2, be made in situ with the metal and acid? I think he asked that earlier?
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garage chemist
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Does anhydrous aluminium chloride react with alcohols?
I read in the thread on methyl iodide preparation that MeI has been successfully prepared from iodine, Al and methanol. That means that AlI3 reacts
with alcohols to produce the alkyl iodides, which would be really convenient if AlCl3 does the same thing.
AlCl3 is not too expensive and reasonably easy to obtain.
(is this the case in Bangkok too?)
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Per
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I don´t remember if I asked that, but you can made it in this way, just drying should be a Problem.
NaNO3 + C2H5Cl > NaCl + C2H5NO3
I thought that this preparation should work because NaCl is a very strong compound and because this works well:
NaNO3 + HCl > NaCl + HNO3
I wanted the Ethylchloride for something else than just C2H5NO3.
I think destillation of C2H5NO3 is to dangerous for me, so I thought I could get it also with Ethylchloride.
I don´t understand the thing with the TCCA, I can also buy it as pool chlorinating tablets, it is possible to make Ethylchloride with TCCA?
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Nicodem
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| Quote: | Originally posted by Per
NaNO3 + C2H5Cl > NaCl + C2H5NO3
I thought that this preparation should work because NaCl is a very strong compound and because this works well:
NaNO3 + HCl > NaCl + HNO3
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Actually the two equations you wrote have absolutely nothing in common. The first one is supposed to be a SN2 reaction, while the second is a ionic
equilibrium (thus you should write it according to the proper conventions).
| Quote: | | I don´t understand the thing with the TCCA, I can also buy it as pool chlorinating tablets, it is possible to make Ethylchloride with TCCA?
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Not directly. Trichloroisocyanuric acid is a powerful oxidant. I don't know how its mention came into this thread but someone probably confused it
with cyanuric acid chloride, an acid chloride that can be used for preparing other acid chlorides and alkyl chlorides from alcohols. The two compounds
are often confused though being of completely different chemistry.
| Quote: | Originally posted by garage chemist
Does anhydrous aluminium chloride react with alcohols? |
Following the link I gave in my previous reply, you will get to a paper discussing a related issue about the efficiency of several Lewis acids in the
chloride substitution of the alcohols. As far as I can remember the authors concluded that of FeCl3, ZnCl3 and AlCl3 the ZnCl2 is the best catalyst
with the use of HCl. I do know ZnCl2 itself does not solvolize in primary alcohols, but AlCl3 certainly should as it is a way stronger acid. But
probably the conversion would not be quantitative like in the case of AlI3, and side products like ethene might be an issue to consider. I guess it is
worth trying if you have AlCl3 to waste or if you wish to form it in situ.
…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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Per
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I heared that it should also possible to prepare C2H5Cl with AlCl3*6H2O.
Can that be possible?
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Nicodem
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No.
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