I have the option of obtaining quite some CH2Cl-CH2Cl. I still am wondering whether I should get this chemical, or not. This depends on what I can do
with it. Storing another liter of not-used toxic chemical is not what I want, I really should have a use for it.
Are there any specific properties, which make this chemical particularly interesting? Does it have specific solvent properties, which are not covered
by other chlorinated solvents like CH2Cl2, CHCl3, CCl4, CHCl=CCl2? I only can find very sparse and scattered information on 1,2-dichloroethane and
most of it is about its toxicity as a chlorinated solvent.
So, if there are interesting syntheses or experiments (especially less known ones) with this chemical or when it has specific solvent properties, then
I would love to read about them.plante1999 - 27-5-2013 at 04:00
If it was me I would take it rigth now. 1,2-dichloroethane is an industrial building block of importance. I have hard time finding it here, as such I
will need to make mine!!
A very nice experiment is to dissolve sulphur in a boilling sol. of NaOH to make polysulphides, and then add the dichloroethane. Continue boiling
until discoloration. You should get polysulphide rubber, aka fuel line rubber.killer_lapin - 27-5-2013 at 11:00
I agree with plant, diversity of chemical is always apreciated at some point. Dichloroethane is stable so you shouldn't worry about decompositon like
ether or THF.
@plant1999 I had an idea few years ago but never tried it since I had the chance to get DCE. So the idea was to reflux ethylene glycol with
hydrochloric acid in presence of PTC to yield a mixture of 2-chloroethanol and DCE.AndersHoveland - 27-5-2013 at 11:12
I believe there was a procedure to make ethylene carbonate with it, by refluxing with zinc carbonate.
Ethylene carbonate is a highly polar solvent that can dissolve both ions and hydrophobic compounds, particularly suited for nucleophilic substitution
on organic halogens.plante1999 - 28-5-2013 at 13:08
So, woelen, will you buy it? If yes, please try the rubber.Nicodem - 29-5-2013 at 07:44
A very nice experiment is to dissolve sulphur in a boilling sol. of NaOH to make polysulphides, and then add the dichloroethane. Continue boiling
until discoloration. You should get polysulphide rubber, aka fuel line rubber.
Quote:
So, woelen, will you buy it? If yes, please try the rubber.
Try how? Without the reference? Please give us the reference.plante1999 - 29-5-2013 at 08:56
The Chemical Process Industries
by Norris R. Shreve
[Edited on 29-5-2013 by plante1999]woelen - 29-5-2013 at 13:43
I ordered a liter of CH2ClCH2Cl and when it arrives I'll try the rubber experiment. Another experiment I'll try is making higher chlorinated versions
of ethane.
Besides this, I also ordered 100 ml of methanesulfonic acid. With NaBH4 this allows preparation of B2H6, another interesting chemical to experiment
with.garage chemist - 31-5-2013 at 12:28
1,2-dichloroethane is also a convenient precursor to vinyl chloride
through thermal dehydrochlorination.
Simply lead pure dichloroethane vapor through a tube heated to 500-550°C with a residence time of 10-20s. Vinyl chloride and HCl are formed, starting
material conversion is around 50%.
The HCl is washed out with water, the vapors condensed through cooling and the vinyl chloride and unreacted dichloroethane separated by fractional
distillation.
I'd like to experiment with vinyl chloride at some point since it is a very reactive monomer which tends to polymerize in a highly exothermic
reaction. Dr.Bob - 5-6-2013 at 05:34
DCE is often used as a replacement for DCM where you need to heat the reaction hotter than 40C or so. It behaves much like it for the purposes of
a higher boiling chlorinated solvent. But I am sure there are interesting things to do with it, and you can never have too many chlorinated
solvents. :-)woelen - 25-6-2013 at 03:26
The 1,2-dichloroethane arrived and I'll first try the rubber experiment. It is an easy one and can be done on a test tube scale.
The experiment of making vinyl chloride also sounds very interesting, but heating vapor at 500 C in a suitable tube is something beyond the
capabilities of my equipment. I have no equipment for such high temperature chemistry. I would love to do that, but I consider it too dangerous,
because I have my lab inside the house at the attic and I'm not willing to take the risk of a fire. For me, chemistry is limited to temperatures of
150 C, maybe 200 C and occasionally a test tube scale experiment at somewhat higher temperature (e.g. boiling hot H2SO4).
[Edited on 25-6-13 by woelen]AndersHoveland - 25-6-2013 at 14:41
Here is the preparation of ethylene carbonate: http://www.bromicacid.com/carbonate.htm
I suspect the reaction would proceed even more readily with ethylene chloride, especially since the transient ZnCl2 that would form would have a
catalytic effect.woelen - 1-7-2013 at 22:56
I tried the experiment of making rubber. I took a very concentrated solution of NaOH and added some solid sulphur. This mix I heated, until all
sulphur is dissolved. This gives a deep yellow solution, with a tinge of brown/green. I allowed this very hot solution to cool down a little bit (but
still quite hot, near boiling temperature of water) and then I carefully dripped in some C2H4Cl2. The first drops lead to violent boiling, but after
these, the liquid has cooled down sufficiently. A thin layer of C2H4Cl2 remained on top of the yellow aqueous layer (the aqueous layer is more dense,
due to the high concentration of NaOH). The C2H4Cl2 slowly turns yellow, it appears that sulphur dissolves in it.
Next, I stoppered the test tube and shook violently for quite some time, in the meantime heating it such that it remained quite hot (but not so hot
that the C2H4Cl2 started boiling). After several minutes, a white flocculent material appeared, which forms a dirly-looking layer of foamy material on
top of the aqueous layer. Most of the C2H4Cl2 is gone at that time.
Finally, I diluted the liquid with 20 times its own volume of tap water and allowed the precipitate to settle. The material is only slightly more
dense than the aqueous solution, even after several days still quite some flocculent solid is floating around in the liquid. Most of it, however, has
settled at the bottom.
The material is off-white. It has a funny smell, somewhat sulphurous, but very different from the smell of hot sulphur. I now allow some of the
material to dry and will try what happens if I heat the material. More will follow...plante1999 - 13-7-2013 at 04:04
maybe try to melt in in one piece with an oil bath.
very interesting woelen, continue!mr.crow - 13-7-2013 at 10:56
Here is the preparation of ethylene carbonate: http://www.bromicacid.com/carbonate.htm
I suspect the reaction would proceed even more readily with ethylene chloride, especially since the transient ZnCl2 that would form would have a
catalytic effect.
Thanks for the link, ethylene carbonate sounds very useful! Can prepare dimethyl carbonate, a safe methylating reagent, from it.
I'm just guessing but if you used 1,2-dichloroethane then ammonium chloride would form instead of driving off ammonia gas and this would ruin the
equilibriumpapaya - 13-7-2013 at 11:57
I wanted to ask if that rubber("thiokol"?) obtained by woelen is soluble in anything?plante1999 - 13-7-2013 at 12:00
Nope, thats the point of using it as fuel line rubber.bfesser - 13-7-2013 at 17:11
[Edited on 7/14/13 by bfesser]papaya - 15-7-2013 at 10:44
As I may try this particular synthesis what is the ratio/concentrations of components for the highest yield ? Also reaction of sulphur with lye seems
to be not as simple as it looks like, there can be many different products (I searched and found different results from different sources: some state
that thiosulfate and [poly]sulfides are formed, others that sulfite and polys). Look into this www.iapws.jp/Proceedings/Symposium05/365Lin.pdf
as it is what I could find for free. At the end if you look you'll see that if overdone you get no polysulfides at all.woelen - 17-7-2013 at 12:03
The reaction between sulphur and NaOH in solution is somewhat comparable to the reaction between chlorine and NaOH. The element disproportionates.
The main reaction is as follows: S8 + 12 OH(-) ---> 4 S(2-) + 2 S2O3(2-) + 6 H2O
Once some sulfide is in solution, you get further reaction of S8 with S(2-), giving polysulfides. This reaction competes with the reaction with
hydroxide. So, once you have some S(2-) in solution, it is very hard to obtain a clean reaction. The net effect is that you get a solution with
hydroxide, thiosulfate, sulfide and polysulfides. The solution is deep yellow. You get a mix, hard to obtain a clean product.
You need to heat quite strongly (nearly boiling temperature of water), sulfur and hydroxide do not react that easily. Once you have some sulfide in
solution though, the reactions becomes more and more easy.
papaya - 17-7-2013 at 12:58
Thank you woelen, and what is recomemded ratio of NaOH to S to take (to get more polys, rather than thiosulphate). Also isn't it possible to perform
reaction by melting them together rather than do it in solution, because I want to start with bicarbonate+sulfur instead of NaOH and think this way
they'll react better, is there any difference ? Also, how much dichloroethane do you need and is it possible to perform in an open vessel or you must
cap it (actually pressurize when heated) ?woelen - 17-7-2013 at 13:30
Bicarbonate plus sulphur most lkely does not work. You need highly alkaline conditions for the reaction. If you want a lot of polysulfides, then use
excess amounts of sulphur. Just add sulphur till no more sulphur dissolves and you get a deep yellow liquid with solid material remaining (which is
unreacted sulphur).
In my experiment I added the C2H4Cl2 to the deep yellow solution and heated the mix such that the C2H4Cl2 was just on the edge of boiling. I did not
cap the test tube. I was shaking frequently and quite violently. It may take some practice to shake a lot without spilling the liquid out of the test
tube The reaction with the C2H4Cl2 is not fast, but after several minutes you
already have some off-white solid.papaya - 17-7-2013 at 13:42
I meant to melt sulfur and bicarbonate together, won't that work ? (I've heard ''liver of sulfur'' was made ancient times that way).
Also if sulfur soluble in dichloroethane,it may be worth to add that solution to NaOH for example (who knows how this affects polyS length and
properties) as a possible alchemical modification..
[Edited on 17-7-2013 by papaya]ScienceSquirrel - 17-7-2013 at 14:03
This is a recipe for sulphur rubber from the Royal Society of Chemistry;
My apologies if it has been posted before.papaya - 17-7-2013 at 14:24
Thanks, from that I learned that NaOH used was only about 5%, rather small, I expected more.. papaya - 19-7-2013 at 13:48
Few more questions regarding dichloroethane uses - how easy it will be to generate acetylene (with NaOH) and also can one obtain ethylene glycol by
hydrolysis of it with NaHCO3 ? In both cases - will solids react with it or is it possible only in water solutions ? Especially glycol is interesting,
because if dry NaHCO3 will react then one can prepare completely water free glycol this way.
Also what else it can be used for?bbartlog - 20-7-2013 at 09:07
2NaHCO<sub>3</sub> -> Na<sub>2</sub>CO<sub>3</sub> + H<sub>2</sub>O + CO<sub>2</sub>
You want anhydrous, don't use sodium bicarbonate. I don't think it's basic enough anyway. Ca(OH)<sub>2</sub> wouldn't be a bad choice I
think. papaya - 20-7-2013 at 12:56
but all these I believe need high temp/pressures and won't work on a lab scale.
Btw, I did my first thiokol synthesis experiment today, first boiled 20g NaOH with12g S in about 100 ml of water, even after half an hour not the
whole sulfur was dissolved and there started to appear strong H2S smell so I finished boiling and filtered it to obtain clear dark red solution (I
have some serious spills during that, so yields are bad). While still warm I gradually added dichloroethane 15ml of total. Since it was about 50 °C
and nothing appeared to take place I put it on a plate to heat a little bit.
As I read in the paper posted here
"Classic Chemical Demonstrations
THE ROYAL
SOCIETY OF
CHEMISTRY
95. Making polysulphide rubber
"
which says to not heat above 83°C otherwise it'll start to boil I was feeling comfortable, however at about 71°C solution boiled instantly and
some solution spatter out of the flask. Later I found that there's an azeotrope with water with b.p about 70 C (from wiki). Also in that paper ratios
look very weird (8g sulfur to 5 g NaOH and 20 ml(!) of dichloroethane) so I found hard way that the information presented there is at least
questionable. Also if I remember correctly woelen mentioned that the reaction is slightly exothermic, well in my case (ratios) it was stronger and
when taken from the heater the temperature didn't fall below 70C for a long time while some yellow lumps started to appear and grow so once started I
could take it off and watch what happens. however that way too much dichloroethane boiled away and I thing some kind of reflux is necessary for better
results.
Now what I need is a good procedure for the highest yields(ratios I took I somehow calculated myself which maybe not ideal), as I think that rubber
itself is interesting and deserves further experimentation (also for pyro guys here - it must be an ideal fuel, as there's sulfur and carbon ''blend''
on molecular level, just add some K nitrate and get "B.P. polymer version", lift up rockets, etc., only obstacle I see is the lack of some solvent for
it which I hope exist). papaya - 21-7-2013 at 12:25
Btw. I didn't throw away the liquid remained after synthesis and separation of rubber that was really stinky and from curiosity I decided to see what
happens if I add some TCCA to it. A vigorous but controllable reaction started with heating and nearly transparent solution turned into ''milk''
quickly. I was pondering what happened to it and as far as I can guess that must bree free sulfur generated by oxidation of remaining polysulfanes and
maybe also thiosulfate in the solution. I didn't separate it yet but I'm nearly sure it's sulfur, so if true there's a good way to recover sulfur from
spent solution (I believe it will work also with common bleach instead of TCCA), what do you think?woelen - 22-7-2013 at 00:19
TCCA itself also may lead to formation of solid material. It produces cyanuric acid and this is only sparingly soluble in water. At high pH, however,
this is more soluble, giving cyanurates.
What is the color of the precipitate? Is it white like milk, or yellow. If it is really white, then I have severe doubts that it is sulphur.papaya - 22-7-2013 at 12:00
Yes I'm aware of cyanuric acid, now when I look into container there's a yellow-white precipitation which is I think a sulfur. Another interesting
thing here that the solution now smells acidic (unlike previous worse-than-rotten-egg smell, which is also the smell of polymer, what is it?) much
more like HCL and when I dropped a bit onto concrete floor it started to fizzle like acids do giving off CO2, very weird given that the solution is
prepared from lye!
[Edited on 22-7-2013 by papaya]woelen - 22-7-2013 at 22:42
If you use TCCA, then formation of acid is not strange at all. Much of the chlorine in the TCCA may end up as HCl in a redox reaction. I once
witnessed this myself, when I added TCCA to ammonia. After the reaction the solution was strongly acidic!
[Edited on 23-7-13 by woelen]papaya - 22-7-2013 at 23:38
Then one must think in chlorine generator setup like yours one doesn't need to use HCl since it can form from the reaction.. Is it possible that
sulfuric acid formed from oxidation of sulfur with TCCA ?
Anyway in this case it's even better, as acidic solution will also convert thiosulfate into sulfur after polysulfides. But TCCA is not economical,
hopefully bleach also works, and to be sure if really sulfur forms a cleaner test is needed like dissolving S into NaOH and then add bleach to check
what happens.Hexavalent - 23-7-2013 at 09:09
Not to advertise, but currently on eBay there is 2 kg of Alfa Aesar 1,2-dibromoethane...
In my book, preparative method of polymer chemistry, I found two procedure that are not lab demonstration, but practical synthesis. the first one is
to make particles of polymer suitable for analysis (It use a polysulphide sol. made with sulphur and sodium sulphide), but the second preparation is
used to make dust of the polymer coated with magnesium hydroxide, the interest? When put into shape, HCl is added and a plain piece of the rubber is
made.
When I will have more time i will transcribe the text here.
The reaction with the C2H4Cl2 is not fast, but after several minutes you
already have some off-white solid.
