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garage chemist
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Half an hour ago I've mixed TCCA and NaOH in water while keeping the mixture cool, then I added a few drops of acetone and the mixture became
cloudy.
The I smelled the reaction mix and was greeted with the lovely smell of chloroform!
A new, high- yielding OTC method of making CHCl3!
No large amounts of bleach needed!
TCCA contains LOTS of chlorine and this reaction converts it ALL to chloroform!
I will elaborate a complete synthesis of chloroform from TCCA.
If anyone's interested, I can write it down when I'm ready.
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UhhKaipShaltaBlet
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Excuse me of my ignorace ,but what's "TCCA"?
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neutrino
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Trichloroisocyanuric acid, a common pool chlorinating chemical.
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chloric1
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| Quote: | Originally posted by garage chemist
Half an hour ago I've mixed TCCA and NaOH in water while keeping the mixture cool, then I added a few drops of acetone and the mixture became
cloudy.
The I smelled the reaction mix and was greeted with the lovely smell of chloroform!
A new, high- yielding OTC method of making CHCl3!
No large amounts of bleach needed!
TCCA contains LOTS of chlorine and this reaction converts it ALL to chloroform!
I will elaborate a complete synthesis of chloroform from TCCA.
If anyone's interested, I can write it down when I'm ready. |
That is awesome! I would like to try the TCCA & NaOH mixture on ammonia mixed with acetone or methylethyl ketone. A little gelatin wouldn't
hurt for cautionary measure. I just need to find TCCA in a container small enough to be economical. How well does TCCA dissolve in water and in
alkali anyway?
Fellow molecular manipulator
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garage chemist
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I'm sorry, I wasn't able to produce significant amounts of chloroform from TCCA and, to be honest, I stopped the research because a supplier
started carrying chloroform and I bought 500ml for 10€.
That's more than I will ever use...
But it's still possible to make lots of chloroform from TCCA by adding HCl and bubbling the resulting chlorine gas into ice-cold dilute NaOH.
This produces NaOCl in a concentration depending on the starting concentration of NaOH. Up to 20% NaOCl are possible. Upon reacting this with acetone,
chloroform will be had in high yield.
This method converts ALL chlorine from the TCCA into chloroform.
Making NaOCl from chlorine + NaOH would also be highly advisable for hydrazine production, because my chloroform attempts directly from TCCA failed
and this indicates insufficient NaOCl concentration in the TCCA + NaOH mixture.
Don't try to make hydrazine with that!
Instead, build a fume hood / get a gas mask / work outside when its windy, produce chlorine from TCCA and HCl and bubble it into cold NaOH. The
resulting NaOCl solution is most likely much purer than the storebought pool chlorinator, this can improve yields with hydrazine production
considerably.
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chloric1
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Wait a minute!
Now I know pool suppliers also sell sodium dichloroisocyanurate. Would this be your reagent from TCCA and NaOH? Or maybe its not that simple. Maybe
the alkali hydrolysizes the TCCA to release free NaOCl. I am not familiar with the oxidizing species involved here though. I once tried a Sodium
Dichlor oxidation of sodium bromide and only got a yellow precipitate. No free
bromine. Anyone a pool expert out there? I would like to hear some input on the stabilized chlorinators
Fellow molecular manipulator
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Eclectic
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Electrolytic Chlorination
Is anyone familiar with a method of producing chloroform by electrolysing aqueous CaCl2 and acetone? I saw this a few years ago but I'm having
trouble locating the details.
[Edited on 18-2-2005 by Eclectic]
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frogfot
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GC, what was the yield of chloroform?
Lately I've been in demand of big amounts of cheap chlorine, in synth of things like S2Cl2. Since calcium hypochlorite here is 40$/2 kg, TCCA
even more, KMnO4 is 11$/0,75 kg and MnO2 is 8$/kg..
...therefore I wanna finally try the electrolytical way.. Since I like mspaint here I've drawed the theoretical setup I'll use. It suppose
to work continiously.
http://img.photobucket.com/albums/v113/frogfot/chlorineelapp...
I've tried to keep it as simple as possible and doable with OTC parts.
So the electrolyte in anodic cell will be continiously refilled by KCl soln so it will have slightly higher level of liquid than in cathodic cell.
The membrane will be composed of glass wool (glassfiber blankets). I dunno if some filler/binder will be needed.. probably yes..
Important thing is to keep appropriate current dencity above membrane, so it wouldn't boil from inside (had some bad experience with salt
bridges..).
9V would be probably enough.
Everything seems to be quite easy to make. Anyone see some obvious mistakes in the design?
[Edited on 18-2-2005 by frogfot]
[Edited on 18-2-2005 by frogfot]
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Esplosivo
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Nice method to produce chloroform, nice and cheap. The chloroform though being organic would probably result in the remains of hydrolysis of TCCA, or
excess TCCA being dissolved in it though. Distillation might be enough to seperate them, but the organic products of hydrolysis might be as volatile
or nearly as chloroform and share the same boiling point (although I don't think so). Am I correct in assuming that the chloroform synthesized in
this way will contain a lot of contaminants?
[Edited on 18-2-2005 by Esplosivo]
Theory guides, experiment decides.
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garage chemist
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I only got some white precipitate and no liquid chloroform. Actually, the smell of chloroform disappeared rapidly from the mix...
You can experiment if you want, maybe you've got more luck than me.
However, I would convert the TCCA into NaOCl via chlorine (from TCCA + HCl) and NaOH and then add acetone to this. This reaction is much cleaner, the
produced chlororform doesn't need to be distilled and the yields are much higher, anyway.
@ frogfot:
Your cell looks good. But the chlorine production will be slow. To make S2Cl2, you would have to run it a long time and keep the sulfur molten the
whole time.
Or you could condense the chlorine into a liquid with dry ice. If you can get dry ice, this would be ideal. Then you can let the chlorine boil off at
the required rate.
The MnO2 seems cheap though. Or is it still too expensive for you?
[Edited on 18-2-2005 by garage chemist]
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chloric1
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Boiling point
You are right about liquifying chlorine at dry ice temperatures. Actually -30F should work. But, I should mention that the plain ice will not have
enough contact surfaces with your receiver to chill it. You need to add it to a nonfreezing liquid until the liquids temperature approaches that of
the ice itself. Try a nonflammable solvent like trichloroethylene. Anywho just realized I have no way to measure extreme cold myself so I need to
find me a voltmeter with a thermocouple! Off to Jameco I go!
Fellow molecular manipulator
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frogfot
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Liquifying chlorine is a bit scary. I do smelly things in homemade fume hood that could vent an acccidental leakage from a normal chlorine generator..
but accident with liquid chlorine would be too much for it..
As for speed, at 10A it would give me 1,16 ml Cl2/s (at 100% efficiency) which is suitable in most experiments..
[Edited on 18-2-2005 by frogfot]
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evil_lurker
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Anyone ever tried to build a DeNora cell?
Basically it uses brine as an electrolyte, graphite as the anode, and mercury as the anode.
When electricity is passed thru the cell, Chlorine gas is formed at the anode, and Sodium is evolved at the cathode. The sodium forms an amalgam with
the mercury, which is then drained off and placed into water. The sodium reverts into sodium hydroxide and the mercury is reloaded into the cell.
The reaction is:
Hg
(Cathodic reduction) Na+ + e- ------> Na (Amalgam)
2Na (amalgam) + 2H20 ------> H2^ + 2NaOH
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12AX7
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I've always wondered how you keep the Na from reacting with the electrolyte; or does the voltage tend to keep that "sealed in"?
Aside from a small contaminant of mercury, it makes very high purity lye industrially, so I've read. Seems to me it would take a lot of mercury
and be kind of complicated in a continuous process (not necessary of course, but with only 2% Na (also as read), almost a necessity) though.
Given this thread is about the other product, it might work for that purpose, just loading the mercury with sodium until it starts fizzing or
something.
Tim
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garage chemist
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@ Organikum:
I have been wondering about the exact amount of chlorine which is produced when a given amount of TCCA is reacted with an excess of HCl.
Today I tried to measure the gas volume, but the chlorine layer above the water was shrinking before my eyes as it dissolved to make sterile water.
But I also found out that the reaction indeed goes to completion, as I used 3,5mol of HCl on 1mol of TCCA and boiled to expell all chlorine, and on
further addition of HCl, no more chlorine was produced on boiling.
In your "Practical production of chlorine" thread, you said that 6mol of Cl2 are produced from 2 mol of TCCA (I saw that you took in account
that the commercial material is only 92% TCCA and therefore the "molar mass" of this product is 250 g/mol).
But in your downloadable calculations on TCCA, you stated that only 2mol of Cl2 are produced from 1mol of TCCA!
What is true now? Am I missing something?
[Edited on 19-5-2005 by garage chemist]
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chloric1
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Preliminary workup
Recently purhcased two 8 oz giant 3 inch TCCA tablets and ground them up with my high tech granulator(ball ping hammer+ziplock freezer bag) . Anywho, I took about 2 or 3 grams in a small beaker and added 50 ml of 31.45%
HCl all at once. It definately made chlorine but the reagents bubbled to a surprising volume. Two thoughts I have; First dilute my muratic acid to
exactly one half with water,Secondly slowly drip the HCl on the solid with extremely low heat. I wanted to see if it was possible to generate a
gentle yet consistant flow of chlorine. Any creative thoughts welcome. Maybe a Kipp generator setup?
Fellow molecular manipulator
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garage chemist
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The concentration of the HCl is very important.
Someone found out that the reaction of TCCA with concentrated HCl does not go to completion. Reaction with dilute HCl gives much more chlorine and the
reaction almost goes to completion.
The TCCA needs lots of water to be able to dissociate into HOCl and cyanuric acid.
The HCl must not be stronger than 15- 20%.
For making chlorine, I use a two- neck 500ml rbf with a pressure- equalized dropping funnel on the middle neck and a hose adapter on the side neck
where the chlorine can be withdrawn.
All joints must be greased and secured with wire, otherwise they may get loose without you noticing until the chlorine gets into your nose.
The TCCA is coarsely granulated, not powdered (to prevent excessive foaming) and wetted with a little water.
When all HCl has been added, the mix must be heated to complete the reaction.
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chloric1
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Thank you
I admit I have been out of the loop as far as practical hands on chemistry goes for awhile. I have a three month old daughter and am going through a
career hiccup. But, Everything now will find its place I am going to stop being
an armchair chemist and get going soon.
Buy the way, if I add water to my TCCA will it help to coalulate it again and give me a satisfactory Cl2 stream or is it too late for my powder? I do
have a few larger particles but 80% is probably 50 or 60 mesh or finer. Ahh, I will play around a little more with it today and tomorrow.
By the way, a little off topic but still chlorine related. I have a pickel jar I will to use as an electrolytic cell/battery and I am sterilzing with
sodium hypochlorite. This morning while doing the TCCA workup, I also added conc HCl to my very dilute hypochlorite(less tahn 1%) to destroy more
organics and left it in the sun. I fugured that would be interesting as we are approaching record heat today. I wanted to see with how fast oxygen
would be liberated from water in sunlight. What I found was that the gases evolved only when a foriegn object introduced. This is of absolutely of
no value except in its academic realizations. But its cool
[Edited on 6/5/2005 by chloric1]
[Edited on 6/5/2005 by chloric1]
Fellow molecular manipulator
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chloric1
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Here is a photo that demostrates the photodissocation of chlorine and water
<!-- bfesser_edit_tag -->[<a href="u2u.php?action=send&username=bfesser">bfesser</a>: reduced
image size(s); attached]
[Edited on 9.8.13 by bfesser]
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Analytiker
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Chlorine gas/liquid color
I worked with liquified chlorine with a headspace quite a while back. I had a sight glass installed at the liquid/gas interface.
Green gas, red liquid. Very Christmas-like.
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kickflip_333
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festive AND fun.
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Mason_Grand_ANNdrews
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I have any useful stuff to the chlorine source. If anyone interested, i will make a samll HTML to the subject.
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Magpie
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I've been wanting to try some chlorination reactions using UV light to generate free radicals for some time. I had read through this thread some time
ago and decided to try the TCCA + HCl method for generating chlorine. My goal was to produce a steady stream of relatively pure, dry chlorine, with
good control. Good control included being able to stop the reaction quickly should something go wrong.
My chlorine generator is a 1 liter suction flask. 18% HCL was to be dropped as required onto coarsely ground TCCA using a 250 mL separatory funnel.
This assembly was sitting on a stirrer-hotplate for heating/agitation, if required.
For a drying train I set up two wash bottles in series partly filled with Rooto sulfuric acid (~96%). The inlet dip tube in each bottle was about
4cm below the acid surface. The glass tubing was 6mm OD and was connected together with 6mm ID Tygon (soft PVC) tubing. Following this is a 250mL
Erlenmeyer flask as safety bottle in case of suckback. Finally, the Tygon tubing was connected to a 7mm OD gas dispersion tube having a fritted end
to produce fine bubbles. This dispersion tube was placed in the chlorination vessel which is a large test tube. In the test tube I had placed some
DCM.
Everything seemed tight so I turned on the 500w halogen lamp and the hood fan, and started dropping in HCl, just a few drops at a time. A
yellow/green gas could be seen in the generator flask right away. But also right away a fatal flaw in my setup was apparent. Due to downstream
resistance an adequate Cl2 pressure had to be built up and maintained in the generator flask. But when this pressure began to build it would vent Cl2
up through the stopcock of the dropping funnel. This can be easily understood when the backpressure is estimated: (2)(4cm)(1.85) = 14.8cm H2O back
pressure just to overcome the sulfuric acid heads alone. Then add in the glass frit resistance and the DCM head of about 8cm and I come up with ~23cm
H2O of backpressure. This was just about right to overcome the head of HCl in my dropping funnel. So now I see why addition funnels with pressure
equalization are useful!
Actually, after reviewing this thread again, it seems like a another absorbant might even be advised. That is, shouldn't the first bottle contain an
absorbant to take out the HCl gas that will surely be a contaminant in the Cl2?
It seems to me that the every gas delivery situation can be different. That is, some will require contaminant removal via solid absorbants (ie,
CaCl2, mol sieves, etc), some will require absorption through a liquid (ie, H2SO4, NaOH, etc), and some may require some of each. In all cases some
amount of driving pressure head will be required. This seems like an important and generic problem that may be encountered by the home chemist. But
I find little or no information, guidelines, etc, in any of my books or on the internet.
This is a long story. But I wanted to get it out as an example of problems that can be encountered in gas generation, cleanup, and delivery. I think
chlorine generation is a good example of typical problems that must be overome.
Below is a picture of rev1 of my chlorinator. Critique, suggestions, and discussion are welcome.
[Edited on by Magpie]
The single most important condition for a successful synthesis is good mixing - Nicodem
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The_Davster
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I use acid filled syringes, with the tubing to the generating vessel secured well, to add the acid to the generator vessel. No issues with the
pressure anoyances here.
Also just realized I have not worked with chlorine for around a year and a half...weird.
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garage chemist
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There is no need to remove HCl gas from the chlorine stream, as your reaction (chlorination of DCM) produces HCl anyway, like most organic
chlorinations do.
Only removal of H2O vapor is necessary (but this is important). Conc. H2SO4 can be used, CaCl2 too.
CaCl2 may be a better choice for you, since it creates far less pressure drop than H2SO4.
While your method of chlorine production sounds good (apart from the issue with the dropping funnel), your method of chlorination has to be improved.
For instance, a reflux condenser is absolutely vital if you are chlorinating anything. Those reactions either have to be done at the boiling point of
the substance, or they produce a lot of heat. Cooling slows down the reaction too much, so refluxing is necessary.
Or did you just want to create a solution of chlorine in DCM? Then you would have to cool with ice.
I doubt that you will be able to get more than one chlorine attached to the DCM, since I have done chlorinations of things like red P in boiling
chloroform and upon recycling of the solvent, no noticeable CCl4 was present.
One last thing: granulated TCCA does not react completely with HCl, since it gets coated with cyanuric acid. You either have to finely powder the
TCCA, or you have to heat the gas generator to boiling after all HCl has been added.
[Edited on 19-5-2007 by garage chemist]
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