NEMO-Chemistry - 13-7-2017 at 17:46
I would like to tit rate the iodine number for various oils, I am aware of tables with approx values, but i would like to do the experiment. We did a
lab at school but not the actual experiment.
What we actually did was watch this video
https://www.youtube.com/watch?v=WQ7WQrJ1A1U
Then we were given a list of values to work out, so no actual hands on work.
Apart from Merk (no chance getting from them!) I cant find two of the chemicals in the video.
One being wijs solution iodine monochloride, and the other Trichloroethane 1,1,1.
The solvent I am assuming could be replaced with something else or made looking at wiki.
i checked Amazon and ebay and no luck for the monochloride, looking at the prep it mentions liquid chlorine and dry ice, this isnt a real option in
the UK.
Does anyone know of a chemical supplier i might be able to get some from in the UK? PM me if you want it kept hush hush .
Merk have it for £55!! But Merk wont sell it to me.
OR is there another way I could do this titration? The oils are the normal suspects plus some used cooking oils and solid fats from various sources.
I would really appreciate some help with this, it seems a really nice analytical experiment and is the kind of thing that interest me.
Thanks in advance.
j_sum1 - 13-7-2017 at 18:13
In years gone by 111 trichloroethane used to be used as a thinner for white-out. You could buy it in little bottles. I don't know if there are any
current OTC products that contain it.
NEMO-Chemistry - 14-7-2017 at 04:24
Tracked down the monochloride, fischer has some they will sell me, but isnt ebay cheap!! they also do wijs solution made up but is alot of money for
added acetic acid!!
No luck with the solvent but apparently all its got to is dissolve everything, so i assume it isnt too critical.
tsathoggua1 - 16-7-2017 at 10:55
I have some ICl, that I'd be willing to trade for and doubtless cheaper than from a chemical company. It is home-made, and originally some ICl3 was
present, although that was removed by allowing the ICl to vaporise in a flask connected to a horizontal column containing solid iodine, between the
ICl (in the column closest to the chlorine generator was where it formed rather than near the receiver)
I don't have any TCE though, it seems like in the UK it is now impossible to find chlorinated hydrocarbon solvents OTC, believe you me, I have looked
everywhere, ended up making some chloroform and buying 10l of DCM online after searching all over the show.
You DON'T need liquid Cl2. Or dry ice. If you want I'd be happy to trade some of mine, to save you the having to deal with making the stuff,
especially if you don't need 100s of grams > (IIRC I've about 50-60g of it, sitting in a bottle in the fridge [no, not next to the eggs and milk
and ergot sclerotia etc., I'd not keep anything that nasty next to my lunch)
But if you want to make it yourself, you can get by, by rigging up a Cl2 generator with whatever reagents you prefer to use for that purpose,
connecting it to a drying tube packed with anhydrous CaCl2, which then leads into two in-line liebig condensers, with a little wire wool between the
Cl2 generator and the back of the dessicant tube, just to stop it falling out into the generator, it'll end up extra-crispy as FeCl3, but this won't
volatilize over into the stream of Cl2 gas, and with the first condenser packed with elemental I2, and the second connected up to a water pump to cool
it and condense the ICl into the receiver. Use a little more than stoichiometric I2, since some ICl3 (a yellowish to orangey solid was noted in small
amounts and not isolated) and leave it to stand in the receiver overnight, so any vapor containing ICl3 traces reacts with the excess I2 forming ICl
again.
Wear good safety gear dealing with this stuff, I've never tested it on a piece of meat, but I've seen enough of what its capable of to know with
absolute certainty that I do not wish to be the piece of meat in question. Had a mask failure (valve working loose, repaired quick) and traces in the
air left me using an inhaler for a few days) so be really. fucking. careful, with this stuff. Cl2, I2, Br2 have nothing on quite how vicious iodine
monochloride is.
How much is the Fischer product for the amount you need? I can probably undercut them.
Hopefully don't need to say so, but better it be pointlessly stated than somebody come to harm because it was left unsaid. This stuff is AGGRESSIVE.
Extremely corrosive, destroys plastics in very, very little time at all in contact with the vapors (as much as came out from a heavily teflon-wrapped
pair of ground glass joints, in the cold of the evening) was enough to disintegrate plastic keck clips so quickly I almost ran out before I could
obtain some stainless ones. Although I'd be very much inclined to use an all-glass syringe in handling it, without a needle, because chances are it
will attack the metal and contaminate the iodine monochloride.
Also it has a weird tendency, just out of interest, although I don't know why, to supercool past its freezing point and remain liquid, this even seems
the case in samples have been left for a long time in the fridge. It has two crystalline polymorphs, with differing MP, but once the crystalline
form/s have been melted its quite difficult to get it to fully freeze again, even after a few months in the fridge at just above 0 'C. Has a tendency
to partially freeze and have a liquid layer remain on the surface.
If you make it, either use teflon tape only on the ground glass joints, or else a fluoroinert type grease (the latter has never been tested
personally, I am making the assumption that a fully perfluorinated hydrocarbon grease would not be attacked. But I'd test that first. Also, don't
leave stoppers in flasks storing it or you'll have nightmares about getting them out again because its a creeper like bromine and iodine, and will
worm its way between the joints and crystallize.
If you don't have any GAA, and don't want to make the ICl, and wish to do a trade, I wouldn't mind throwing in a little GAA, for, if anything, token
compensation and the cost of shipping+something to put it in (I only have a few bottles that will resist the ICl, 3-4 of them at most so I'd need to
get a suitable container for it. The ones I have, were left here by the filth on one of their brutalization campaigns, and not sure what they are made
of, but the plastic cap and inner seal underneath it have managed to remain intact during months of storage. Also, it has not attacked the teflon tape
wrapped round the screw threads.
Stuff fumes something nasty and my bottle of GAA has been opened and a fair bit used, so I'd dry that thoroughly before use because ICl hydrolyzes in
H2O and the fumes, again, aren't something you'd want to breathe in. Would recommend a full face-shield before handling it. Best way to transfer it to
a bottle, short of a glass funnel would be using a short length of perfluoropolymer tubing to mate together a pipette and glass syringe, although
plastic tubing can be used, if you make sure never to let the ICl come into contact with the tubing and use the syringe only to fill the pipette.
Shoot me a PM if your interested.
NEMO-Chemistry - 17-7-2017 at 08:30
I will send you a pm, I got to go out but will be back later cheers
NEMO-Chemistry - 17-7-2017 at 08:42
You cleared up one question I had, i did wonder why we didnt actually do the experiment. I thought it would be a good one to do, hearing your
description of Wijis i can see why my teacher wasnt keen on my class getting near it lol.
I have a great teacher, but the class is unfortunately packed with idiots. We havnt learnt much as playing about seems to be the number one aim of
most in the class.
Like I say i will send you a pm later, I better get the new fume hood sorted first and a few other things done!! GCA I can probably get hold of or
make.
Stock up on sulphuric acid , someone I know and who is in a position to know, says
sulphuric acid is likely to banned before summer break of parliament!! Apparently there is a great deal of support for it, and alot of MP's calling
for its ban......I wont get political but beggars belief they would do it.
You can guess what will quickly follow this, the other stuff used for unblocking drains .
tsathoggua1 - 17-7-2017 at 22:03
It wasn't Wijis' that Tsath' was referring to. It was iodine monochloride itself. The stuff is virulent as hell. And I can see why a beginning (?)
student would not be let near the stuff. Its one of (although not the worst) the most noxious chemicals Toady has ever handled, including things like
distillation of about a liter of chromyl chloride, distillation of white phosphorus. SOCl2, etc. ICl is less friendly still. Short of the speed of
many solvents poured neat onto styrofoam, Toady has never seen such rapid attack and disintegration of plastics than when exposed to traces of ICl
vapor. He managed to make his outside, wearing a mask with a cartridge rated for halogens (since its still a halogen-halogen bond, only asymmetric
with respect to the atomic species, the reactivity is similar enough that a mask can that will protect against bromine, chlorine and iodine vapor will
do it. You don't want to use a mask with rubber straps though or it'll rot them within hours if there are more than traces around whilst your doing it
and turn the polymer flaky and friable, liable to falling apart if rubbed between fingers. Plastic keck clips, cannot be used unless you have enough
you want rid of, to replace them every 10-20 minutes or so (20 is optimistic) and that, is at ambient temperature of an english (NW) evening.
And you bet I'll be stocking up on sulfuric. Don't want to have to start buying it at sigma prices, or having to wait for it to arrive from eastern
europe or from china. You know what its like, I'm sure..those times when you need something and you need it two weeks ago, before you even thought of
the project that makes use of that something
woelen - 17-7-2017 at 23:18
I do not agree that ICl is more noxious than SOCl2, CrO2Cl2 or white P.
ICl certainly is corrosive, but it is not more so than Cl2 or Br2. It must be treated with respect, but you should not exaggerate its properties.
White P is much more risky. It is self-igniting in warm air (summerday heat) and is extremely poisonous (more so than cyanide and in small quantities
it also is very harmful in the long run). CrO2Cl2 also is much more risky than ICl. In contact with organics it can lead to spontaneous ignition and
its vapors are strongly carcinogenic.
I would have no issue with distilling some ICl (I actually did distill Br2, which is appr. as corrosive as ICl), but distilling white P would make me
really nervous.
NEMO-Chemistry - 18-7-2017 at 03:56
I have looked at other methods of finding the iodine number, however most have a significant error factor apparently and wij's seems the best way. It
just seems a really cool tit ration to do.
I have read several papers that say it dosnt store well and two that say it does, one of the ones that say it does was written by Wij.
maybe trying to get hold of Wijis would be better
tsathoggua1 - 18-7-2017 at 09:12
Don't know about Wijis, but do you mean that the solution doesn't store well? or ICl does not. Mine seems to have been stable over months, after maybe
2.5-3 months on the lab shelf. and another few months in the fridge at a couple of degrees tops. There is, at least, no disproportionation to Cl2 and
I2 visible. If it happens, then in a compact sealed bottle the reactivity is high that it must be recombining with any lysed compound and returning to
ICl. There has never, even with a sample left outside in the garden in the sun (through a heatwave as well, one of, although not the hottest on record
for many years, recently and it looks and behaves exactly the same as it did when first synthesized) (took me that long, after being unable to attend
to it for a while, because I had to wait until I could afford to buy fresh tanks for my mask before I even attempted to open the setup.
Also, if you want, and of course are prepared to trade something in return for the ICl (I don't mind throwing in some GAA for nothing, or if you
insist, then just a token something along with it, unmixed, to make up some wijs', I have plenty GAA, last time I bought any I got a 10 liter can and
I've still got something like 5l left so I can spare a bit of GAA for you if you have none or have only a little left) Or could mix up the solution
before sending it.
I've seen ICl set things on fire woelen, and your right about the carcinogenicity of CrO2Cl2. I should have remembered its hydrolysis into Cr (VI). As
for SOCl2, acute toxicity wise I'd definitely say ICl is the worse of the two by a long shot. I've got enough whiffs of SOCl2 in the past without
coming to harm, but after a mask fuckup where the one way mouthpiece valve worked loose, due to working in the sun, hot and sweaty in there over
hours, a single, SMALL breath of ICl, after underestimating the distance taken in scarpering from the scene long enough to take the mask off and slip
the seal on, there can't have been much around to begin with, left me needing an inhaler for several days, and I am not asthmatic. Made it really hard
to breathe. I'd take working with SOCl2 over being exposed to ICl any day, having experienced both. And once, as a kid, after finding some large SOCl2
cells in a unit that at one point, must have been the power source for a security alarm in a demolished site of some kind, but when I got to it, there
were just piles of bricks, and the small piece of smashed up wall, plus the batteries. Hoping for lithium cells, given their long life/low
self-discharge rate and that being ideal for security alarms given their at most periodic, low rate of power requirements, of course I lifted the lot
for my lab. Didn't realize it they had SOCl2 in them and the first one I opened ended up with SOCl2 pouring over my hand, eating through the
steel-spiked leather glove I was wearing on that hand and corroding the metal spikes as it did, before carrying on to chew into my hand, and releasing
a great cloud of noxious fumes as I plunged it into water. I got burnt down to the muscle and could see bits of tendon. And unsurprisingly it hurt
like all fuck when it was attacking my hand, still got the scar from that (plus a later encounter, accidentally coming into contact with some HClO4)
Was about 8-11 at the time, and my hand still looks like this. Looked (and felt) a lot worse than it does now, looked like a slab of raw steak, if it
had a non-dehydrating strong acid poured all over it and left to pickle in it but I wasn't wearing any breathing gear, only eye protection and gloves,
not expecting there to be anything but at the most dangerous, lithium inside, since I hadn't even heard of thionyl chloride cells at the time, and of
course Li isn't what you could call volatile, just reactive and flammable, and besides can be picked up with dry hands if not handled carelessly, and
handled quickly, if it really has to be done.
Despite the lack of any gas mask, I didn't suffer any breathing issues, only severe burns at the point of contact with my hand. From an inhalational
point of view, I definitely view ICl as the nastier of the two, by quite a long way. Just one little whiff and on the bronchodilator inhaler for 3-4
days after.
Of course I was an awful lot more careful with the rest of the fair haul of pretty decent sized batteries I'd scavenged once my hand healed enough to
take another crack at opening them up to recover the SOCl2, with thankfully, no further incident aside from its nasty ass smell. I hate to even
imagine what would have happened had I spilled the same amount of ICl without a mask in my workspace, even if it hadn't touched my skin whatsoever.
Agree about distillation of WP making you nervous though, I don't blame you. If it didn't, then you probably wouldn't have much of a survival
instinct its the sort of task one better HAD be alert and aware when
undertaking. Although I have to admit, after obtaining my first WP, again in my youth, after spending gods only know how much time cutting off
matchbox strikers and stewing them in acetone, etc. before evaporating the solvent off and doing a distillation to remove the ground glass and convert
the red to white..the glowing eerie green cold fire, coupled with its pyrophoric nature..thats the sort of thing that held me fascinated for months of
reading up more about P chemistry and its allotropes. Its been my favourite element of the lot ever since because of the fascinating diversity of its
allotropy, and the really useful and broad spectrum of the reagents and reactions its capable of being made to perform, the phosphine ligands that can
stem from the element and its vital nature to human life and genetic structure, getting to stand on the shoulders of Hennig Brandt and peer out at
what he must have felt and seen when first he discovered WP after his labours (albeit without boiling down 'hogsheads of urine, left to putrefy until
it breed worms'...
.for some strange reason I do not believe for a moment that my parents would have looked too kindly about my either collecting, or worse, boiling
down bathtubs-worth of putrescent, insect-larvae-infested stagnant piss. They probably thought, if they'd have known the history before I started and
finished the experiment and coming to show off my latest prize that scraping and stewing a whole load of matchbox striker pads and distilling a
pyrophoric poison was quite a blessing compared to the alternative way of going about it. To say nothing of wondering why A-there was a scavenged
bath-tub filled with stagnating rancid human piss in the garden and B-why a large apparatus that could plainly only have been intended for lighting a
fire in the garden under said tank full of rancid human piss, was being constructed, had that approach been taken. Or for that matter, C-why their son
was repeatedly seen ferrying milk bottles full of piss out of the house)
They were tolerant enough of my experimenting, inasmuch as they had any idea quite what I was up to, or quite how far my chemistry experiments and
supplies had evolved from the little plastic test tubes and tiny bottles of mostly boring utilitarian padding in modern-day suck-arse kid's early
chemistry sets, but I think that would have been a step TOO far
With respect to corrosive nature of ICl...I don't have a great deal of experience with elemental bromine, but I'd say ICl greatly exceeds the
corrosive nature of gaseous Cl2. Being a liquid probably contributes quite a lot, in cases of direct exposure to a susceptible substrate. But
considering I had the same identical keck clips on both the Cl2 generator and the regions where the ICl was coming out, it was only the ones, of those
used in the experiment, exposed to Cl2 only, and at a higher concentration probably, that survived in one piece without cracking or disintegrating.
Also if you are concerned about the shelf life of ICl, then I could make some up fresh for you, I've got the iodine, and a dirty great big drum of
strong hypochlorite from which to generate the Cl2, dry argon with which to sweep the Cl2 through the system, CaCl2 to dry the Cl2 etc. and any
leftover I can use to get around to fully chlorinating some ICl without having to use up what I have bottled up in the fridge in order to make some
ICl3. I just need an excuse to go and do it really
[Edited on 18-7-2017 by tsathoggua1]
woelen - 18-7-2017 at 10:34
ICl has indefinite shelf life, but only so when it is stored in a very well sealed container. Best would be to put it in a glass ampoule and seal
that.
ICl does not decompose on storage. The affinity between Cl2 and I2 is quite large and once you have ICl they do not easily separate again. ICl3 is
another story. ICl3 is labile, it easily loses a molecule of Cl2 and in fact exists in equilibrium ICl + Cl2 <---> ICl3. ICl3 is best stored
under an atmosphere of Cl2.
I noted another interesting property of ICl3. It is insoluble in non-polar solvents. If you take some I2 and dissolve that in e.g. CCl4 (or CHCl3 or
CH2Cl2 or pentane), then you get a clear deep purple solution. If you bubble Cl2 through this, then you get a brown solution. ICl is a covalent
molecule which dissolves easily in apolar solvents. If you bubble more Cl2 through the solution, then the liquid becomes turbid. First turbid brown,
with impure ICl3, contaminated with ICl. When more Cl2 is bubbled through then the liquid becomes turbid and yellow. I think that ICl3 in the solid
state is not simply ICl3, but ICl2(+)/ICl4(-).
tsathoggua1 - 18-7-2017 at 12:15
Does cooling down make for a good way to precipitate it (either relying on Cl2 stabilization in solution phase, or assisted by continual passage of a
stream of Cl2, or Cl2 diluted in a carrier gas?
I noticed, during my first synthesis of ICl that some of an bicolored material, some regions orange and some yellow formed, in the region of the
iodine-packed column closest to the Cl2 generator (a dessicant tube packed with freshly baked out anhydrous CaCl2 was interposed between generator and
the liebig stuffed with I2, and a small tuft of iron/steel wool stuffed up the backside of the the drying tube, as a sacrificial 'mount' of sorts, to
secure the dessicant from falling back into the generator but I can't really picture the resultat FeCl3 easily vaporising and passing through 3-4.5
inch or so of CaCl2 at RT, and if it had, I would have definitely expected some coloration.introduced by deposition of the halide in the earliest
portion of dessicant, that nearest to the Cl2 generator and to the Fe.
The material seemed to be present in distinct zones and patches, some a pure yellow color some an orange, not quite as vivid as fr.ex. the pumpkin
color of 2,5-dimetboxy-4-methyl-beta-nitrostyrene before its being cleaned, duller and not so refringent but of a quite similar hue. Appearance was of
a finely grained powder deposited in layers, although whether the packing was loose and easily dislocated or tough and adherent and tightly packed as
polycrystalline material which would separate in plates or flakes I don't know, since there was an excess of I2 present. I assume that co-deposition
of ICl3 and this being then saturated or otherwise bathed in and having absorbed some ICl during primarily the vapor phase, may have been the reason.
Oddly it occurred in two distinct regions. One being the place of interface between the Cl2 stream (diluted in Ar as a carrier gas, as I did not at
the time know how vigorous or violent the reaction would be, and didn't want a sudden, violent reaction that either might have damaged the glassware
if such had taken place, chewed me up, or worse, both.) as it was, the reaction, when using Ar to push the evolved Cl2 stream through the apparatus
and after reaction and condensation using a second condenser running H2O through the jacket (a liebig) exiting out through the receiver into a line
connected to a two-part trap, jerry-rigged from glass bottles known to have caps at least to a degree, resistant to chemical attack
(amber glass bottles received from a pharmacy, and built up for use in storing various chemicals, given out in dispensing my prescription for
chlormethiazole, a drug which is known to like eating plastics) although I didn't expect them to resist being attacked by something quite so
aggressive as ICl, at least not for very long. They didn't have to really, since these were in order, an empty bottle running two lines, one in, one
out, the inlet connected to the receiver flask and, interspersed with a 1-way gas valve (wasn't sure how it would respond to fluids, or if it would
simply have the insides burnt to a crisp) from an aquaculture store, and then to a short line connecting it to the second bottle, secured first with
cyanoacrylate, and then with epoxy at the interface between the holes for the lines, put in with a hot piece of metal to give a tight fit, just to
help further retard any escape of the vapor, into a wash bottle containing saturated sodium carbonate solution in order to both hydrolyse any escaping
ICl3 and convert it, ideally, into iodate.
although it has not yet been checked to see if I2 can be liberated and recovered from it, since the setup is going to be re-used in order to consume
the remaining I2 since it is of course now only fit for this purpose, and not to be returned to the tub of I2 chunks I have in the fridge (one
dedicated to chemical storage, not food, unless food for thought counts ) since
its been exposed to the ICl.
I just need to find the time to be inclined to don my mask and face shield, gloves etc. and go fire up the Cl2 generator flask when the weather isn't
uncomfortably hot (especially remembering the mishap with the mask before, definitely don't want a repeat of that, and now that its summer, there is
more light available so I can work later which for me is ideal (since I am really not a morning person unless it means I've been awake all night and
am just about heading to curl up on the sofa for the day and sleep. Some people need their coffee or other stimulant in the early morning and start to
eat and go to work. For me, that is about midnight-2am and I'm ready for my pre-sleep-cycle pain medication and seizure prophylaxis, adrenolytics and
the like and to not wake up until at least 6-7PM ideally once it begins to get light again (and I don't like being in sunlight much either, since
after the filth tampered with something in an attack directed at my lab (no, not a raid, there is a difference) and as a result I've been left with
one of my eyes extremely sensitive to bright light. I was somewhat photosensitive, in a sensory manner to begin with, but after getting my eye burnt
badly and near blinded in one of them it can hurt like hell just laid eggs in there)
The bicoloration of the ICl3 which formed transiently, before reformation of ICl on contact in the vapor phase with excess I2 was not unexpected at
the interface between Cl2 and I2, but more surprising afterwards when with considerable iodine still packed in the bore of the first liebig there was
the same afterwards at the exit point of the vapor stream from the I2. There I expected it to be either ICl or I2, or both. Or if any ICl3 was present
for it to be the same color.
Is there any known reaction between ICl and ICl3? Never noted a brown color, other than the vapor phase of ICl.
Also, is I2 soluble in ICl in the liquid phase? if so, to what extent? or if unknown then how readily does what is soluble dissolve? (and in what
state of the I2, finely divided, or in this case more applicably, larger pieces (from say 2.5-4mm lower range to a the size that will, with a little
persuasion, just about fit into the inner bore of a 24/40 liebig) since the I2 I have is not the usual flakes, fine resublimed 'flowers of iodine' or
small prills, but large, irregular lumps, some almost the size of my thumbs end joint at first receipt of the container of I2 before any vaporization
had chance to take place.