12AX7 - 14-1-2006 at 09:40
I'm sure this is covered elsewhere, but my particular situation doesn't seem like it would fit very well. I have a solution of, I susupect,
chromium[III], sodium, chloride, sulfate, and possibly cupric ions. Might as well toss ferric on the list for good measure. I have been evaporating
it to crystals, and had a moist brown mat of crystals (argh, damn acicular habit!). (The brown color makes me suspect something coppery, but on
dilution it turns green, not blue.) After passing a post by Woelen I thought I would try washing it with acetone to seperate the aqueous and solid
materials for drying. I diluted it about half with acetone. It made a complete brown solution with some crystals in the bottom; clearly, a lot
dissolved in the acetone. I drained and dried these crystals and obtained some blue to green acicular crystals, which make a blue solution on
dilution. Alright, seems like CuCl2.2H2O to me. The remainder had no solids, so I put it, water, acetone and all, back on the warm spot overnight.
This morning, I picked up the jar and noticed a distinctive spiciness. No odor, but definetly irritating. I worked on a few other items for a few
minutes, then finished, and decided to move the acetone-ized solution to a cool resting place for the moment while I get some responses. Ten minutes
later, and my eyes are at last comfortable again.
My question, what possible reactions are going on here? I'm guessing a chlorination of some sort? What are the main lachyrmatory molecules made from
acetone? What would the transition metals have to do with it?
Tim
sylla - 14-1-2006 at 10:09
If I remember well, polychlorinated acetone is a lacrymator. Can be done by flowing Cl2 through hot acetone and so is a byproduct of TATP done with no
care (H2O2 + HCl + heat -> Cl2)
I have read on rhodium that monochloroacetone (free from polychlorinated acetone) could be done by boiling acetone with LiCl and CuCl2.
Probably monochloroacetone is also a lacrymator or maybe the longer exposure gave you polychlorinated acetone... You should check the boiling point
with distillation.
[Edited on 14-1-2006 by sylla]
12AX7 - 14-1-2006 at 11:25
Don't have any distillation hardware. 
Lotek_ - 14-1-2006 at 13:00
what about the method used by brain?
http://www.geocities.com/brainfevert/hno3.html
The_Davster - 14-1-2006 at 13:45
That could work, however you would need a thermometer hole in there somehow.
Could you start at the very beginnng of your experiment? Like what you dissolved in what to get the origional solution.
EDIT: Bromic, I think brainfevers baggie distillation method keeps a pretty good isolation between what is being distilled and the outside
environment. However whatever is in there is likely not in a huge concentration so a large ammount of acetone would have to be distilled first, and
Brainfevers method does not lend itself well to large volumes.
[Edited on 14-1-2006 by rogue chemist]
BromicAcid - 14-1-2006 at 13:49
Ummm... need I remind everyone this is a lachyrmator, something I don't think 12AX7 wants to try and distill, expecially with some rigged up impromptu
distillation apparatus. I'd also say it is some chlorinated derivative of acetone, I've had enough experience with burning eyes to know acetone is
readily chlorinated and the products burn terribly. I'm sure there are other tests for the chlorinated product besides a distillation but the
chloride in solution would likely give a positive test for them as well.
woelen - 14-1-2006 at 14:12
On long standing of a solution of CuCl2 in acetone I also noticed a reaction. The smell of the acetone changed. It became more pungent and more
irritating. The solution became turbid, so definitely there was a reaction (copper (II) being reduced to copper (I) ????). I did not investigate it
further, I just concluded that if I do experiments with CuCl2 in acetone, that I should do these experiments quickly.
I'm not sure if this is the same as what you observed. If I use acetone for rinsing and drying purposes, then I usually dry it quickly. I put the
crystalline mass on a tissue, such that most acetone is sucked out into the tissue, then I put the mass in a petri dish and I use a hair dryer for
blowing off the last amount of acetone (be careful, not to blow all the solid around the room, I once had that 
). I do not store a solid with large amounts of acetone overnight.
12AX7 - 15-1-2006 at 16:19
Checked the solution this evening. It still has some acetone in it, but the irritating compounds have gone away. The color is a nice even green,
either chromic or chloro-cupric. I found a fine greenish precipitate in the bottom, along with small (approx. 1mm, 1/16") transparent, colorless
octahedral crystals (quite remarkable really, I don't see octahedrons very much 
). I seperated these and tested with water and acetone; neither appeared to dissolve them much. Acetone caused the remaining (green) solution to
become yellow to orange (a color somewhat darker than orange dichromate solution) and precipitated a whitish salt (perhaps more of the octahedral
salt?). I have the crystals drying now. As the acetone dried, the color inbetween crystals (presumably, green to yellow solution trapped in the much
finer crystals) turned from yellow to light green, interestingly.
Any thoughts on what salts form colorless, octahedral crystals?
Tim
Endo - 16-1-2006 at 06:52
This looks interesting,
I am trying to get to CuCl Cu(I) for some organic chem reactions...
Any way to tell for sure that you ended up with the Cu(I) complex?
Thanks
12AX7 - 16-1-2006 at 07:23
Well right now it's green, not brown, but copper chloride solutions certainly do turn brown when reduced. There is an organic chemical present (how
much reducing power does acetone have, anyway?), but it must not be strong enough, if there is enough copper present.
Tim