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papaya
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TCCA bleach
How to check if pool bleach tablets I got (there was nothing but ''aquachlor'' written) are made of Trichloroisocyanuric acid or Sodium
dichloroisocyanurate? It doesn't dissolve readily in water, but better in acetone (though a little residue remains undissolved) and when adding water
to acetone solution the whole turns into gel-like state(small needle-like crystals). Also it's not a calcium hypochlorite, because when dissolved in
water (well, very little I guess) it'll not give CaCO3 precipitate if NaHCO3 solution is added, instead CO2 bubbles are evolved .
Then, what will be the reaction product of TCCA with sodium nitrite, could you replace chlorine atoms with .. nitro groups that way (any good
solvent?) ?
[Edited on 23-4-2013 by papaya]
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Vargouille
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Sodium dichloroisocyanurate is much more soluble than trichloroisocyanuric acid in water, while it is much less soluble than trichloroisocyanuric acid
in acetone. Also, large tablets are more likely to be trichloroisocyanuric acid, since sodium dichloroisocyanuric acid is sold as granules as a
chlorine shock, while trichloroisocyanuric acid is used to keep the "chlorine level" up from day to day.
Someone else will have to comment on the reaction part of that.
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papaya
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Thank you for answer, what I have are really big tablets and rather dense, but to be sure what it is I'm looking for some specific property or test..
About reaction with nitrite - well that seems to fit to ''enrgetics'' section, because if what I wrote is possible, the structure of hypothetical
product resembles that of hexogene(replace methylenes with carbonyles in it and see), and no nitric acid needed at all .
Anyway I hope someone knowledgable will answer.
[Edited on 23-4-2013 by papaya]
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Metacelsus
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Watch out when dissolving TCCA in acetone - you could end up making chloroacetone after awhile (the reaction is autocatalytic).
http://www.sciencemadness.org/talk/viewthread.php?tid=18953#...
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papaya
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I dissolved it in acetone only to see if it could be dissolved in any solvent, used small quantities, but didn't notice any reaction that time.
Still hope hope to find out what it is. If it's a TCCA, is there something interesting it can be used for (except bleaching )?.
[Edited on 23-4-2013 by papaya]
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woelen
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If it dissolves in aceton, then it almost certainly is TCCA.
Crunch some of the material so that you get pea-sized particles. Take a few of those particles and add 10% HCl. If a lot of Cl2 is formed (clearly
visible green color of the gas) and the liquid contains a lot of solid white matter, then it is TCCA. If a lot of Cl2 is formed and the liquid becomes
clear, then it most likely is calcium hypochlorite. It never will be a mix of TCCA and hypochlorite, because of the incompatibility of these two
chemicals (mixing them leads to a very violent and really dangerous reaction as soon as the mix becomes wet).
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papaya
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Thanks woelen, I'll try chlorine test with HCL , also as I understand if reacted with H2SO4 it must NOT give much chlorine, right? And as I wrote it
reacts with bicarbonate releasing lots of CO2 and slowly dissolving,there's no CaCO3 formation, certainly it's not Ca salt, but is that specific to
Sodium Dichloroisocyanurate or trichlor or both? When small quantity of it is heated on a plate to red hot in the flame, first it melts and decomposes
giving odd greenish-blue colors to flame, but it then leaves some solid residue looking like molten salt layer on plate, which coldn't be decomposed
further, that's why I suspect it could be sodium salt (otherwise it's not pure).
And what do you think about reaction with nitrite? I guess there must be some solvent capable to dissolve both TCCA and NaNO2, maybe DMSO or
acetonitrile will work? Is the reaction possible even theoretically(as I know it works with alkyl halides to give nitroalkanes or nitrite esters)?
And about other uses - can one convert it to potassium chlorate by boiling with KOH? Couldn't it be used as an oxidizer itself in pyrotechnical
compositions instead of chlorate? Sorry if I ask too many questions, it may be irritating.
[Edited on 24-4-2013 by papaya]
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woelen
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Na-DCCA and TCCA both dissolve in alkaline solutions, but if you have tablets, then you don have Na-DCCA. If the things do not contain calcium, then
the only remaining option is TCCA. Some brands of swimming pool chlorine tablets are said to contain TCCA, mixed with some other chemical, but I only
have seen pure TCCA (at least not anything added intentionally).
TCCA is very reactive. DO NOT USE THIS IN PYROTECHNIC COMPOSITIONS! TCCA reacts with many fuels and can lead to spontaneous ignition!
Making chlorates with TCCA is not a very economical process. You can make Cl2 (by adding HCl) and then lead that through a concentrated solution of
KOH, but keep in mind that for each mole of KClO3 you make 5 moles of KCl and separating the KClO3 from this may lead to quite some losses. It can be
done though. In the cold, KClO3 is much less soluble than KCl and hence can be separated fairly easily.
I do not believe that TCCA reacts with nitrite to some nitro compound. It simply oxidizes nitrite ion to nitrate.
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papaya
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Thanks again Woelen, the production of chlorate I speculated is not through the route of CL2 synthesis, but directly boiling TCCA with KOH, or with
NaOH, or even with Na2CO3 (NaHCO3) and then react with KCL. I'm aware about being non-economical, but given that many people try to make it with a at
most 10% household bleach, and also TCCA and baking soda are easily obtainable, this may be viable if works.
Also what I tried: few 100 mg-s of substance added to test tube and then few ml of water didn't dissolve it. Then adding few drops of concentrated
H2SO4 also did NOT dissolve it (and no gas evolution), instead test tube became enormously warm (don't think this is reaction just with water, because
it is warmer where crystals are at the bottom). Then after it cooled down I added a little NaCL to test tube (instead of HCL), a gas started to evolve
rapidly, it is most likely chlorine ( the smell spread is not that awful as usually chlorine smells, I may err - didn't sniff enough ). Also tried to dissolve in acetone again - there's lot's of undissolved stuff
remains, looks like NaCL, but then why it didn't give chlorine with just H2SO4?
Any suggestions where the stuff may be useful are welcomed.
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vmelkon
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Quote: Originally posted by papaya ![](images/xpblue/lastpost.gif) |
Also what I tried: few 100 mg-s of substance added to test tube and then few ml of water didn't dissolve it. Then adding few drops of concentrated
H2SO4 also did NOT dissolve it (and no gas evolution), instead test tube became enormously warm (don't think this is reaction just with water, because
it is warmer where crystals are at the bottom).
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Did you add concentrated H2SO4? It would sink to the bottom of your test tube and warm up. Why don't you add low concentration H2SO4, such as 20%?
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woelen
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If you add dilute H2SO4, then you create a solution of HOCl and you get a slurry of cyanuric acid.
Be careful with TCCA when mixing with organics, especially when combined with acids. I once mixed some TCCA, acetone and conc. sulphuric acid. Nothing
seemed to happen. As soon as I added a drop of water, I had a flash of fire and the contents of the test tube was ejected from the test tube!
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papaya
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As I mentioned before the stuff is not completely soluble in acetone, so to find out contaminant in what supposedly is TCCA, I isolated undissolved
residue from acetone solution, washed with excess acetone (didn't dissolve anymore) then dried. Some of this powder I put into gas flame dispersed on
aluminum foil. First it melted and bubbled a little, then sticky melt formed, which didn't decompose anymore even when red hot, so it's not organic. I
noticed that when touching the flame it gives a slight green tint to it. I know that chlorine can color flame if some copper is present (but mine is
Al foil), but suspected more that the thing man be boric acid! I put some of powder into test tube added few drops of 95% ethanol then heated- solid
dissolved and the liquid became somehow oily, also not as volatile as pure alcohol. Then I finally put one drop of liquid on fire and it burns with a
deep green color, so I think I proved it to be boric acid? Why they should add boric to the TCCA in tablets (approx. 1/4 or even 1/3 is boric), what
is the purpose of it? Also, how I can get rid of boric acid, without using acetone (boric acid is only slightly soluble in water, like desired TCCA)?
Also Woelen, about reaction with sulfuric - I didn't notice ANY reaction, it even didn't dissolve (diluted acid) so are you sure on formation of HOCl
in sulfuric? Of course when I added few crystals of NaCl chlorine started to bubble out, but that's another story.
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I can buy pool Cl tablet here in the UK but they contain "Calcium trichloroisocyanurate" as the active ingredient. Can you have a calcium salt of
TCCA? If not what the hell are they selling? I could understand calcium bis(dichloroisocyanurate).
Or is this just manufacturer's "techno-twaddle" to obfusticate the the true, and very simple, composition of the tablets? At 200g each a bit hard to
swollow.
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papaya
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First time I hear about Ca salt of TCCA. But mine contains no Ca and seems to be a mixture of TCCA and boric acid (what for?). I'm looking how can I
purify it, any ideas?
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woelen
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Boric acid (and also borates) are powerful flame suppressors in fuel/oxidizer mixes. I can imagine that this is added as safety measure in order to
make the TCCA less dangerous in case of fire. TCCA, which is in contact with a fuel, is very dangerous in case of a fire. When there is boric acid in
it, then the fire will be suppressed and will become much less intense.
I would use this TCCA just for making chlorine gas. The presence of the boric acid is not a problem at all in that application. For other experiments
I would try to find other TCCA, which is pure. I purchased chlorine tablets with 92% active chlorine, which translates to appr. 100% TCCA.
TCCA does not seem to react with H2SO4, but when a reductor is added, then you see a violent reaction. Especially pure TCCA with conc. H2SO4 and an
organic is a dangerous combination. It may set off on its own, or after adding just a drop of water.
Calcium trichloroisocyanurate is nonsense. TCCA is a molecule, devoid of protons, which can be split off to make a salt. DCCA can form salts. It has
one H(+) which can be replaced with Na(+), but TCCA has no such hydrogen. Maybe the material contains calcium hydroxide or calcium carbonate? I think
it is just TCCA with some filler added.
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papaya
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I don't want to deal with free chlorine gas, because I don't have proper glass to make a generator, also it's not safe doing it without fumehood and I
don't know where I'll use it except making NaOCl. I prefer to work with solid stuff, unfortunately it's not pure and much precious acetone is needed
to dissolve/filter/recrystallize it. I searched the forum and there were some threads regarding TCCA, especially looked at this one (may we react it
with urotropine?):
http://www.sciencemadness.org/talk/viewthread.php?tid=20296
unfortunately threads die at the most interesting point everywhere and no conclusion can be made about synthesis with starting TCCA.
At last it may be utilized in a way this guy does (with Ca hypochlorite) https://www.youtube.com/watch?v=32kT1_23ICU
Won't it work even with boric acid contamination ?
Or if it can digest copper in acidic solutions use it for PCB etching..
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papaya
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I'm sorry to ask this here, I'm not sure it was not discussed in the long hydrazine related thread, but what if TCCA is boiled in alkaline solution,
wouldn't it generate hydrazine without addition of urea? I mean as cyanuric acid and NaOCl will form in situ if TCCA is reacted with NaOH, and also I
read somewhere that cyanuric acid is attacked by hypochlorite solution (though it was written NCl3 forms, but with ammonia it's also believed that
NCl3 can form, still Raschig process works!). I noted that when TCCA reacts with NaHCO3 solution after reaction is complete the solution has a strong
pungent smell (chloramines?), which I think indicates that cyanuric acid really breaks down and then I wonder why this should not work?
Does a procedure like " to a calculated amount of hot NaOH + gelatine solution TCCA powder is gradually added under stirring, then solution is cooled
down and hydrazine extracted (somehow, with H2SO4 or MEK) " deserve a try, what do you think?
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papaya
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I know you seem to be a little tired of this stuff, still I have some news which may be of interest to individuals who loves generating a lot of
chlorine gas Anyway, I was trying if it is possible so etch away the thin
copper layer on PCBs, for this I decided to make a TCCA+NaCl slurry in water (well not a thick mud, but lot's of undissolved material on the bottom of
test tube half filled with water) then I put a copper sheet in it. I want to mention, that before putting copper in there was no reaction observed for
a long time, and after - slowly some gas startet to evolve, then faster and faster (it smells of chlorine), some copper went into solution and gave a
pink insoluble salt (which looks similar to the complex salt I've seen on woelen's site) crystals of which where floating everywhere. At some monent
liquid in test tube started to boil giving out chlorine gas(I believe) and I started to think - what if the reaction is catalysed be copper ions. I
prepared a similar mix of TCCA+NaCL+water then trew few little crystals of CuSO4 into it. With a time same reaction started lazily and I don't think
this is just because CuSO4 hydrolysis gives some acid, because even with such a little quantity of CuSO4 reaction didn't stop after some time.
However, I was very impatient and added more CuSO4, it accelerated reaction a bit, same pink crystals formed, and it seems (not sure) that gas bubbles
out of surface of these crystals. So if this is truly a catalytic reaction, then chlorine can be made of TCCA with NaCl instead of HCl, but also the
fact this happens is very interesting to me, someone has any information about Me catalized reactions with TCCA ? (if I were woelen(sorry), I would
make a mixture mentioned here, but instead of CuSO4 use the pink salt he made already to see if the same happens )
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macckone
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Copper is a catalyst in a number of reactions, there is no reason to assume that it couldn't act as a catalyst of some sort here. The NaCl may not
even be necessary.
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papaya
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Continuing tests with different metal salts this time I went with MnSO4,KMnO4, CoSO4 and FeCl3. When added a tiny MnSO4 to TCCA/water no apparent
reaction took place, and it dissolved fully, no any color change was observed. Then adding NaCl also didn't cause any significant chlorine generation,
but color of solution slowly turned to yellow-brown, I suspect due to microscopic MnO2 particles formed in solution. Next I tried with addition of
KMnO4 to TCCA/NaCl/H2O and it readily turns into MnO2 flakes in solution, also it destroyed most of ''organic'', because undissolved TCCA at the
bottom decreased in volume, gas evolved for a short time, and test tube was totally contaminated with MnO2 sticked to it (needed oxalic acid wash).
With cobalt I had no luck at all, it dissolved making nice pink solution otherwise not interfering with anything, so no reaction observed. With FeCl3
it gave some gas, solution turning into rust color (but there's no precipitation so far), most of TCCA disappeared, perhaps was destroyed with Fe3+. I
was too lazy to test Ni2+, perhaps next time or someone of you interested will do. So the Cu2+ case (works best with copper metal) seems unique, but
I'm starting to think that this is not a catalytic action, but rather copper forming insoluble complex and thus shifting equilibrium. If I had some
CuO or copper cyanurate I could check this, but I don't.
[Edited on 28-4-2013 by papaya]
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papaya
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Though with FeCl3 I was too fast to make conclusions, now I looked at the test tube and the gas generation still continues - slow but steady.
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woelen
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I tried the experiment of papaya with TCCA, NaCl and copper.
TCCA + NaCl gives the smell of chlorine, but nothing more. No bubbles, no reaction.
TCCA + NaCl + copper powder gives a little bit more of chlorine, first the liquid turns blue/green, lateron it becomes purple. No bubbles, but fairly
strong smell of Cl2.
Heating of TCCA + NaCl + copper does not lead to much changes. Some of the copper dissolves, but no strong reaction.
Finally, I added some boric acid. When this is done, then I obtain production of chlorine gas. The reaction is not violent, but enough Cl2 is formed,
such that the green color of the gas can easily be observed. The liquid becomes darker purple, more copper dissolves.
I personally think that the boric acid is essential for the reaction. Boric acid is a very weak acid, but apparently it is sufficiently acidic to
allow production of Cl2, the boric acid itself being converted to borate.
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papaya
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Wow, thanks for the test, it turns out boric acid contamination in my TCCA played a key role. I can't imagine how it will convert to borate (copper
borate?) if purple complex forms, or if it'll form borax with Na, then why copper is needed for the reaction? Could you please test adding some of
purple copper complex that you previosly made from cyanuric acid (must be relatively pure) to TCCA+NaCl solution (must be saturated, most of solids
undissolved). What I want to see - if the effect is catalytic, if yes, then this is definitely interesting!
Did you wait long enough before adding boric acid btw? What I saw the reaction is self accelerating in the beginning (copper buildup?).
[Edited on 28-4-2013 by papaya]
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woelen
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I did two tests on a small scale (test tubes with a few 100's of mg of TCCA and similar amounts of other chemicals).
Test 1 is TCCA + NaCl + tiny pinch of purple copper complex
Test 2 is TCCA + NaCl + boric acid + tiny pinch of purple copper complex
The TCCA was crunched, such that a fine powder was obtained. It was mixed with the other solid (powdered) chemicals. Finally some water was added.
The mix with boric acid was more active than the other mix, but both were fairly tame. I had no violent reaction. The mix with boric acid at a certain
point in time developed chlorine gas and was foaming slowly, but I had no violent reaction.
Finally, I added both mixes to each other and started heating. When this is done, then production of chlorine becomes faster and the liquid starts
foaming more. The liquid becomes bright purple.
After the experiment I decided to clean up the stuff by adding some ammonia (appr. 10% NH3). I poured the stuff on a piece of glass and then poured on
the ammonia. I had a very loud BANG, and after that a whistling sound in my ears for a few minutes Most of the liquid was gone after the explosion. The remaining liquid first was deep blue, then it turned lime green
and then a lot of gas was produced.
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Bot0nist
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What do you think was responsible for this explosion? NCl3? Where the liquids hot and a reaction in the gas phase happen? (I have seen this reported
when a member was dissolving TCCA in hot sulfuric or acetone. Cant remember which.)
Sorry, just postulating here.
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
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