Methylene Chloride

[Alchemist]

Hello all,

does anyone know of a good OTC source for Methylene Chloride? Thanks!!!!

[mongo blongo]

It's also called Dichloromethane and is easily found in hardware stores used as a paint remover and cleaning up epoxy resin. It will also be found in paint and varnish stores. It usually contains a small amount of methanol (about 10%) which can be removed by distillation. Are you thinking about HNO3 solvent extraction?

[nbk2000]

The more expensive "pro grade" paint strippers are mostly MC. Also, it's mixed in with toluene and acetone. I don't know the percentages, but an MSDS would tell you. I can by it neat for $20 a gallon here. Though I'd have to pick it up at the factory since they can't ship it. :(

Since it's boils at 40C, and around 30 degrees C lower than the next highest Bp solvent (acetone 70C), and way less than toluene, it'll be easy to distill. You'll need a very cold condenser to collect it though since it's nearly boiling at warm room temperature.

I've been studying the solvent HNO3 extraction process for the DVD. I'd go with freezing out the anhydrous nitric acid if I had access to dry ice (which I do). Though I wouldn't bother with distilling off the dilute nitric in the first place.

Rather, use the NO3/H2SO4 mix, add an excess of acid, and do multiple extractions with MC. Freeze the combined extracts to -60C and collect via filtration the anhydrous crystalline HNO3. Let thaw and you've got it.

How simple is that? :D No distilling required at all, everything available cheaply without suspicion, and it's pure anhydrous to boot.

[spydamonkee]

MC can also be found in spray cans of Belt Grip for softening big conveyor belts to make em grip better. it also contains toluene
dunno how oyu would go about seperating the two since its in a spray can, prolly not the best source :D

[SATANIC]

IIRC, the best source is the cheap brands of paint stripper. it contains only 10% methanol.

look in supermarkets rather than hardware stores,you'll usually find it, otherwise, try a cheapass looking hardware place.

[da man]

I think i remember reading a while ago in the patent for this that the nitric acid with the methylene chloride still present in the acid, can be used for the nitrations without the methylene chloride interfering. Would this work for the prodcution of RDX? All you would need to do is mix the nitric and sulphuric acid, add the methylene chloride, suck off the sulphuric/water layer, and PRESTO! Acid for RDX manufacture!

<small>[ July 25, 2002, 05:39 AM: Message edited by: da man ]</small>

[kingspaz]

just like to point out acetone actually boils at 55.5*C not 70 <img border="0" title="" alt="[Wink]" src="wink.gif" />

<small>[ July 25, 2002, 07:05 AM: Message edited by: kingspaz ]</small>

[nbk2000]

Excuse me for not installing the Merck Index. :rolleyes:

Anyways, the patent says it's a "gentle" oxidizer. You're not going to use it for trinitro-anything synths. Though you could easily use it for making MNT or dinitrophenol for conversion to PA.

I like how you can simply freeze out pure anhydrous acid without all the distilling crap and NOx fumes to hassle with.

[Alchemist]

Hello all,

Thanks a million everyone! This went over so good I should give ya all my entire list of 18 chemicals I am looking for!!!

Again thanks, byeee......

[Microtek]

As it happens, I'm currently trying to establish whether this is a viable method for producing very pure nitric acid.
I have a feeling that the reason I get poor yields from my HMX procedure is too much water or NO2 or both in my distilled HNO3 ( which works fine for making RDX ).
I can buy CH2Cl2 from my supplier, but I wanted to try extracting it from paint remover to avoid the shipping costs. Over here all paint removers contain some sort of colloidal material as a thickening agent for easy of use on vertical surfaces. I don't know what it is, but previous attempts have shown that it is pretty inert.
I found a brand that was reasonably cheap, and contained from 60 to 100% CH2Cl2 ( that's what it said on the label - pretty wide margins ), 1-5 % xylene and then that gelling agent.
I found that simply mixing the product with some xylene ( 20-30% ) and distilling the mix worked fine; much of the CH2Cl2 came over and left a cake of xylene and gelling agent that was easily poured out.
Condensing the vapour was much easier than I had anticipated; I just made sure that the condenser tube ( glass ) extended well into the receiving bottle. The vapours can be seen as a diffraction because they are so much more dense than air and when I looked across the mouth of the receiving bottle, no spill could be seen.

The distilled methylene chloride still contains some kind of aromatic substance, probably xylene which is nitrated when the CH2Cl2 is used to extract HNO3 from mixed acids, causing the solvent to turn red or black. However, the nitroaromatic that is produced is easily separated from the CH2Cl2 by a second distillation.

When I do this, I employ a sandbath and monitor both the temperature of the bath and of the vapour in the distillation flask. I keep the sand bath at 70 C. Surprisingly little CH2Cl2 is lost.

[ALENGOSVIG1]

Methylene chloride can also be found in auto shops and hardware stores as "acrylic solvent". Its usually pure methylene chloride.

Also, i have a procedure fot TNT that uses methylene chloride/nitric acid extracted from KNO3/H2SO4. The only problem is that you need tons of methylene chloride. But you can distill it off so you can reuse it. You could make a makeshift distillation apparatus to distill methylene chloride easier than nitric acid.

[nbk2000]

Well, since acetone and MC Bp's are within 15C of each other, there will be some carrying over of acetone into the distilled MC.

But, fortunately, MC is insoluble in water, while acetone is freely soluble. Thus, a simple washing with cool water (several times) will remove the acetone contaminant.

You could make a spiral condensor from PTFE tubing wrapped around a dowel, and insert it in a straight length of PVC piping with a T fitting at the lower end. The PTFE tube connects to a glass tube that passes through the stopper at the bottom.

The reason for the T fitting is so that the water that results from the melting of the ice chips that you pour in the open top of the condenser can drain out. A small screen keeps the ice in, of course,. :) and a stopper connected to another tube carries off the melt.

Ice is a much more efficient means of condensing the MC than just plain water. Also, your receiver should be ice packed too.

Reason for the PTFE tubing is because you might need to use the condenser (in normal water cooled mode) for distilling the nitric if you run out of MC. Two birds, one stone. <img border="0" title="" alt="[Wink]" src="wink.gif" />

[nbk2000]

(I've moved this to the special project section since it's now mostly about nitric acid purification than about finding MC.)

I'm wondering...would it be OK to add the dry ice directly to the MC/HNO3 mix?

Reason I'm asking is because this would greatly simplify the process since you wouldn't need a seperate cooling bath, just do it all in one pot. :)

I don't think it would react since both CO2 and HNO3 are acidic.

Naturally you'd want to be very careful to add the dry ice in very small pieces till the raffinate is cold, otherwise you'll get acid splattering everywhere. Ouch!

I'll have to see if I can find some straight MC at the auto suppliers since I already have everything else, or can get it within a few minutes. Only thing I don't have is the equipment (or inclination) for a distilling setup.

[Mr Cool]

Dry ice wouldn't react with HNO3 or MeCl2, but you might get clouds of HNO3 and MeCl2 vapour before the liquid was cold, like when you put dry ice in water.

[nbk2000]

I figured that might be the case. If one has a deep freezer, it be advisable to use that to pre-cool the raffinate as much as possible. At -20, that'd only require another 30 degrees of cooling by the dry ice to freeze out the anhydrous nitric, conserving the amount needed.

[megalomania]

The dry ice should actually a freezing mixture with DCM that may get quite cold by simply mixing them. In chloroform at least you can get to –77 C.
In my chemical survey I came across a few brands for painting. Some of these are gelled with crap, and can be quite expensive. The first brand I found is 84% DCM, with the other stuff being isopropanol 6.5%, methanol 3.5%, and other. It was $7.95 a quart, and $20.95 a gallon (3.8 L). The second brand included isopropanol, ethylene glycol monobutyl ether, and methanol. It was $28.50 a gallon with no listed %’s. The third included acetone, toluene, methanol, and other. There were actually two similar brands here (one was gelled I suspect) which cost $17.99 and $16.99 a gallon. The fourth included methanol, toluene, and acetone. It was only $9.99 a gallon.
I suspect there is much data on obtaining pure OTC dichloromethane at The Hive.

[DBSP]

I've made some searches on metylenechloride and found out that it is banned in sweden not even chem companies can buy it without a special permission. To bad, is it the same in other companies?
All chlorinated solvent are banned here.

My chem supplier has is at the prize of about 75$(x1,25=~94$) per 4l(pure).

[Mr Cool]

Mega: I've been playing with "Nitromors" brand paint stripper recently (the only listed ingredients are DCM and methanol), it's very thick and cloudy white. BUT: if you pour it into an equal volume of water and stir it well for a minute, then let it settle, the DCM settles to the bottom (clear and colourless), the methanol mixes with the water at the top, and the thickener pptes and settles between the two liquids. So if all brands contain this thickener, it's very easy to seperate. The DCM layer is roughly 70% (v/v) of the paint stripper that you used.

[megalomania]

Ahh yes, I forgot to mention two things: that DCM is only slightly soluable in water (hence easy to seperate the alcohols and acetone), and that pure DCM is illegal in the US (to the best of my knowledge).

I am unfamiliar with the method of nitric acid purification using DCM, is there a patent or another source I can check this?

[nbk2000]

Damn newbies! Always asking for people to spoon feed them information! Search!

<img border="0" title="" alt="[Wink]" src="wink.gif" />

US#3981975 Preparation of anhydrous nitric acid

It's listed in the "patents" topic by me in the links section, in wantsomfets' post.

<small>[ July 31, 2002, 08:52 AM: Message edited by: nbk2000 ]</small>

[Microtek]

Mr Cool: The Nitromors brand is also sold in Denmark and I used it some time ago as a source for DCM. I settled on the same extraction method that you did, but found that the DCM obtained still contains some sort of dissolved plastic, which can be separated by distillation.

[PrimoPyro]

Megalomania, what exactly do you mean by "pure" DCM being "illegal" in the USA??

Illegal how? To buy? Or to makret in _______ product? Anyone can purchase it from a supplier without scrutiny. I may be unaware of domestic laws in your area however, that may prevent it's usage in certain applications in pure form.

But I know for a fact that it is considered to be a benign chemical in the eyes of the organic chemist. It is my favorite solvent, as is common for many an o-chemist.

For those of you in the USA having troubles finding it OTC, stop looking there altogether. Buy it from a chemical supply company, just call them up and outright ask them, "Hi. I'm interested in purchasing a solvent. Do you do business with individuals, or only companies?"

A)Yes they do business with individuals, then you say, "Ok, I would like to order 2 liters of dichloromethane solvent. I have the CAS Registry Number if that would help. (Have this number ready for every compound you ever wish to order, it makes their job ten times easier and helps them believe you know what you are doing with this solvent.) What am I using it for? I am a general contractor and painter, and its the best solvent for cleaning pigments from brushes and equipment without damaging them.

Bla bla bla.

B)They don't sell to individuals, only businesses, you ask: "Oh really? That's a shame. Do you happen to have the name and number of a company that does sell to individuals? Thank you, have a wonderful day, ma'am." (click)

It's easy as pie. Heh, or you can bee a little nerd funny and tell them you use it as colone because you love the smell, and then ask if they have ether as well. :D

[EDIT] I also forgot to add that dichloromethane forms an azeotrope with water, and other azeotropes with many other solvents. Simple distillation will not fix this.

PrimoPyro

<small>[ August 07, 2002, 05:08 AM: Message edited by: PrimoPyro ]</small>

[nbk2000]

Since the MC would be used for nitric manufacture, a little water wouldn't have any real effect since it'll either be removed by the H2SO4, frozen out, or passed over into the HNO3. You may not get 100% anhydrous HNO3, but 98% ain't nothing to sneeze at. :)

But a dryer like anhydrous magnesium or potassium sulphate would remove combined water after the distillation.

[Mr Cool]

Microtek: Yeah, the specific Nitromors I'm using (they have paint stripper, paint brush cleaner, varnish cleaner, varnish remover, etc etc etc etc etc etc) has some petroleum distillate of some sort, which stays in the DCM. I've found it can be frozen out quite easily.

[megalomania]

In regards to the illegal reference, I meant that to apply only to OTC products for household use. The chemical must be adulterated in some way before it can be sold to the public; this is more of an environmental thing, and certainly may not apply everywhere.

[nbk2000]

Something glaringly obvious (in hindsight) just occured to me.

The reason why the patent specifies methlyene chloride ISN'T because it's the most effective but, rather, the most convenient solvent to use.

By looking at the table listing the extracting power of various chlorinated solvents, we see that the more fully halogenated the solvent, the less effective it is.

Thus, carbon tetrachloride is less effective than chloroform which is less so than methylene chloride.

But I think that, if we continue with this line of thought, that we'd see that methyl chloride would be most effective of all.

Methyl chloride is a gas above (IIRC) 4*C, thus requiring refigeration to keep liquified. This would complicate industrial scale processes which require maximum economy. But, to the HH (Home Hobbiest), maximum EFFICIENCY is the goal.

Methyl chloride is (IIRC <img border="0" title="" alt="[Wink]" src="wink.gif" /> ) easier to make than DCM, requiring simply passing HCl through MeOH, and condensing the gaseous product.

Since the easiest way to seperate out the raffinate in the patent is to freeze it out with CO2, you'd already have CO2 on hand for liquifying the MC gas. And, once seperated, the MC could be allowed to evaporate off, or be recycled.

Feasible?

[PrimoPyro]

It will be contaminated with hydrogen chloride and water vapor that will need to be removed.

[nbk2000]

I'm assuming that a person would have the good sense to purify their solvents prior to use.

The question is, would methyl chloride be more efficient than DCM for extraction of HNO3?

[nbk2000]

The methyl chloride generator consists of a 5-l. flask resting on a sand bath and fitted with a reflux condenser, with a delivery tube running from the top of the condenser to a train of wash bottles, two containing water and two containing concentrated sulfuric acid, with three safety bottles, one at each end of the train, and one between the water and sulfuric acid bottles.

To charge for about 45 moles (theoretical) of methyl chloride:
200 g. of water and 2.2 kg. (1.2 l.) of concentrated sulfuric acid are placed in the flask, and 1.4 kg. (1760 cc.) of methyl alcohol is added, with cooling, at such a rate that the temperature does not rise above 70°.

Then 2.4 kg. of sodium chloride is added, the apparatus is tightly connected, and the flask is heated on the sand bath so that the gas is evolved at a fairly rapid rate.

It has been found in practice that, using materials of the commercial grade, the yield of methyl chloride is about 55 to 65 per cent of the theoretical amount, so that about double the calculated quantities must be used.

[rikkitikkitavi]

Or you can use Lukas- reagense ZnCl2+HCl+MeOH and reflux it.
ZnCl2 acts as the catalyst/nucleophilic agent.

Unfortunately I dont have a link, I just read it in my Organic chemistry book, but it is a standard nucleophilic substitution.

It is also described in Vogels (chapter Alkyd halides, p272 for n-butyl chloride) but with larger carbon-chains and both primary and secondary alcohols. Nevertheless , it is appliable to MeOH.

It also works in reverse (MeCl+ H2O =&gt; MeOH + HCl) but due to the volatility of MeCl yield is probably not so low.

/rickard

[nbk2000]

I just got back from Wal-Mart where I picked up the stuff to try the process.

I got a can of DCM in a product called "Aircraft Remover" (made by Klean-Strip), 18oz (weight), for $4. It's DCM with less than 4% methanol. That's it...straight DCM in a can. :)

It was in the automotive section near the body filler stuff called "Bond-o".

Got the stump remover, the gloves...only thing missing is the acid. That's next week, along with the dry ice to freeze out the raffinate.

Should I bother with washing out the methanol? Or just use it straight? Only side effect I see of not removing the MeOH would be possible methyl nitrate contamination. But that'd be such miniscule amounts...

[Pu239 Stuchtiger]

I must say that the difficulty of building an HNO3 still is being greatly exaggerated. It would take me less than an hour to rebuild mine. It's simply two flasks, a glass tube, a propane burner, and a sheet of fused teflon tape. The yellow HNO3 that is the result of NaNO3/H2SO4 distillation has a density of 1.51g/cm3. NO2 is easily removed with CO(NH2)2; H2O is easily removed by placing a beaker of the HNO3 in a tightly sealed aluminum pot with a beaker of 98% H2SO4 for a few days (keep the pot in a warm, but not hot, area if possible).

Much easier than toying around with dry ice, methylene chloride, etceteras... and a lot cheaper. Each milliliter of 100% HNO3 costs me about $0.02 to prepare.

[nbk2000]

And anyone can make a still from 2 beer bottles. Your point?

This topic isn't "Distilling is better than...", it's about using DCM for preparing anhydrous HNO3. Keep it on topic.

And who needs dry ice? You can simply boil off the DCM, or distill it at low temperatures and recycle it forever.

Here's a (possible) nitric synth so simple it's practically k3\/\/l. <img border="0" title="" alt="[Wink]" src="wink.gif" />

NITRIC ACID...the 3@%Y way

Stump remover, acid, 2 glass jars, can of DCM, and a can opener.

1. Mix stump remover and acid in jar. Let sit while you view your Sailor Moon H collection. :p

2. Turn can of DCM upside down and hold down nozzle till all pressure is released. Open end with churchkey can-opener.

3. Pour 1/4 can of DCM into jar. Put on lid and shake a minute. Let settle. Pour off DCM into other jar.

Repeat #3 till out of DCM.

Leave jar of DCM/nitric in sun till all DCM evaporates off. Cap off jar of remaining 98%+ HNO3.

No boiling hot acid splattering everywhere, no fire, no broken glass, no NOx fumes, nada.

Simple or what? :D

Use dry ice and you can get 100% ANHYDROUS CRYSTALLINE nitric. You CAN'T get that by distillation.

Cost? Same as the method you mentioned, only without the added expense of urea to remove the NOx impurities you get by doing it that way.

[Pu239 Stuchtiger]

You wouldn't want to leave HNO3 in the sun, because the concentration will go down as it yellows due to being broken down by light.

Unless CH2Cl2 is free, distilling is cheaper. :-p

42mL of HNO3 would theoretically take $0.27 of H2SO4 and $0.20 of NaNO3 to prepare. Factor in a slight loss of yield, the cost of propane (I get around eight hours of burn time for a $2 canister; it takes about thirty minutes to distill 60mL of HNO3), and the next to nothing cost of a tiny amount of urea - the cost of 100% HNO3 is going to be around $0.02 per milliliter.

I'm saying just because earlier on this thread this CH2Cl2 method of extracting HNO3 was being spoken of as being cheaper, easier, etceteras... which I disagree with.

[vulture]

This might not be entirely on topic..

How about preparing anhydrous HNO3 by adding anhydrous MgSO4 to your nitric acid? The MgSO4 hydrates to MgSO4.12H2O which falls out of the solution if you do not stir it. The HNO3 can then simply be poured off.

Drying nitric acid in a dessicator with 85%+ H3PO4 might also be interesting since conc. H3PO4 is insanely hygroscopic.

<small>[ August 22, 2002, 02:02 PM: Message edited by: vulture ]</small>

[nbk2000]

Well, I got some acid yesterday and was prepared to try the process. After spraying out some of the paint stripper into a jar of cool water (to remove the methanol), I noticed this foamy shit and a lot of off-gassing as the cleaner sank to the bottom.

The stuff burned like acid when it touched my skin and formed a solid cake at the bottome of the jar on cooling in ice water.

Soo....there's obviously more than just DCM and methanol in the cleaner. I'm pissed that the full ingredients weren't listed on the can like they're supposed to be. So I'll have to call the manufacturer monday and get a listing of the ingredients. Maybe I'll just have to distill of the DCM first. *sigh*

Guess I'll just have to occupy myself with an NG synth.

[mongo blongo]

I have just tried that with some more strange results. When I poured the DCM/Methanol into water it settled at the bottom and turned into a jelly like substance with bubbles in it. The DCM I had was very old, possibly 5-6 years. When I have some more cash I will get some more fresh DCM and try again.

[nbk2000]

I called their technical support section and got ahold of someone.

It turns out the ingredients are (In order):

DCM
Ammonia (gas dissolve in DCM)
Paraffin Wax
Methanol

I'll have the exact ratios within the hour since he's e-mailing me the MSDS.

The concentrated ammonia would certainly explain the burning, and the wax the foaming.

So, it seems some work will have to be applied to purify. Distillation to remove the wax, nuetralization to destroy the ammonia, and washing to remove the methanol. Bummer.

If I had a car I could just pick up a gallon of pure DCM from the plant for $25. :( It sucks being broke.

Does DCM or ammonia destroy rubber? I could easily enough make a still from a bottle with a copper tube going...oops...can't use copper with ammmonia gas. SS tubing then, with the spout going into acidified ice water to neutralize the ammonia and condense the DCM.

+++++++++++++++++++++++++++++++++++++++++

Just got the MSDS:

METHYLENE CHLORIDE 75-80
PROPELLANT 15- 20
**
ABOVE INGREDIENT CONSISTS OF THE FOLLOWING:
PROPANE 70- 75
BUTANE 15- 20
ISOBUTANE 10- 15
**
METHANOL 1- 4
NONYLPHENOXYPOLYETHOXYETHANOL 1- 5

No ammonia or wax listed, so either he got the wrong product, or they've changed the formulation since the MSDS was printed. But the 75%+ DCM content is encouraging.

+++++++++++++++++++++++++++++++++++++++++++

I've done some testing on the product.

I added an excess of 10% sulphuric acid to the product to neutralize the ammonia. After the fizzing ceased, I decanted off the water layer, and washed the yellow layer several times with tepid tap water (shaking and letting seperate) to remove excess acid and methanol.

The remaining yellow "blob" form a clear (piss yellow) layer with a foamy layer on top. When cooled in ice water, both sections would solidify into a thick mass that wouldn't pour out. On warming again, it would regain its liquidity.

I sniffed it and it reminded me of chloroform. This explains the "blob" behavior, since chloroform does the same thing in water (except the foam and solidifying part).

I noticed a waxy residue floating on top of the ice water when I poured the blob into it. The yellow blob at the bottom remained fluid, but thick and opaque, while waxy bits floated on top.

Determining the Bp of the "blob" will show if it's DCM or not.

<small>[ August 23, 2002, 03:21 PM: Message edited by: nbk2000 ]</small>

[mongo blongo]

<a href="http://216.239.37.100/search?q=cache:ZnamOjuEhroC:ehis.niehs.nih.gov/roc/ninth/rahc/dichloromethane.pdf+Dichloromethane&hl=en&ie=UTF-8" target="_blank">http://216.239.37.100/search?q=cache:ZnamOjuEhroC:ehis.niehs.nih.gov/roc/ninth/rahc/dichloromethane.pdf+Dichloromethane&hl=en&ie=UTF-8</a>

Under the Properties part it says that is has a sweet chloroform-like odor.

[nbk2000]

I boiled some in a test tube and it did so at 40*C, so it's definitely DCM. After boiling for a bit at 40*C, the residue started to get hotter after it stopped boiling, thus being the wax.

I tried iceing the can down before spraying it out to minimize DCM volatilization but, as expect, the shit wouldn't spray out. Likely because the stuff solidified in the can.

So it seems the way to clean up the product is to wash with acidified water to neutralize the ammonia, wash with water to remove the salt, than distill to seperate the DCM from the wax.

Carbon tetrachloride also has a chloroformish smell. I sniffed it (once) just to know what it smelled like. I guess that series all smells the same.

Now, according to the patent, chloroform will also work, but with only about a quarter of the efficiency. But that may be acceptable since making chloroform requires only a bucket, ice, bleach, and acetone. I know the process works because I've done it. Compared to finding pure DCM, it might be easier to just make mass quantities of chloroform.

[vulture]

If DCM works, how about using trichloroethylene? I don't know in which purity, but it's certainly OTC.

[Rhadon]

But both trichloromethane and trichloroethylene have a significant disadvantage: Their boiling points are higher than that of dichloromethane.

</font><blockquote><font size="1" face="Verdana, Arial, Helvetica">code:</font><hr /><pre style="font-size:x-small; font-family: monospace;"> BP
dichloromethane........40 °C
trichloromethane.......61 °C
trichloroethylene......87 °C</pre><hr /></blockquote><font size="2" face="Verdana, Arial, Helvetica">I think that this could be a reason why trichloromethane works worse than dichloromethane does, because when distilling off solvents with higher boiling points some of the nitric acid will decompose. At least if it is done at atmospheric pressure. If vacuum distillation is applied, this is not the case, obviously, but being able to get pure nitric acid without having to distill under vacuum is the only advantage of the CH2Cl2 method in comparance to the directly distilling H2SO4/HNO3.

[mongo blongo]

Right, I have got some DCM (paint and varnish stripper) from B&Q (UK chain store). It is the B&Q brand which was next to the "Nitromors" brand which was more expensive, hence more lightly to have other shit in it to help remove paint.
This stuff is a thick, colorless,transparent gel which made me think- Fuck!!! WTF is in this shit!!!??? :mad:
I didn't have access to the MSDS data so I don't have a clue!
I sat down and thought that since DCM is quite dense, it may settle down to the bottom when added to water. I think I was right!

I added the thick gel to some cool water and the gel settled to the bottom. I mixed it up with the water with a glass rod very well. The gel started to turn white and congeal. This told me that the DCM was probably being "sucked out" of the gel leaving just the other components of the paint stripper which congealed because of the absence of the solvent (DCM).The DCM(?) settled to the bottom!
I now had three separate layers. The top one was water, the middle was the white congealed shit and the bottom was a transparent/milky liquid of what I believed to be DCM (uncleaned).
I have now filtered out the white shit and I have two distinct layers of water and DCM. There is still a very thin layer of the white shit which got through the filter paper. This shit now seems to be clumping together and should be removed with another filter.

What I plan next is to filter and add some water and shake it to wash out any methanol that I suspect is still present in the DCM.
I also know that DCM is slightly soluble in water so there may be some water present in the bottom layer of DCM.
Of course this is BAD for HNO3 solvent extraction!
I have two ideas of removing water.

1) To freeze out the water in my freezer and filter out the crystals.
2) To wash it with H2SO4 to dehydrate it and it should separate into a different layer which can be separated prior to use with HNO3 or XNO3/H2SO4.

In respect to my second idea, the DCM could alternatively be stored under water to prevent any evaporation of the solvent. When you want to use it, you could wash it with H2SO4 to dehydrate it and use both layers for the solvent extraction (extra H2SO4 to concentrate the HNO3).
It depends on which you prefer. <img border="0" title="" alt="[Wink]" src="wink.gif" />
From the amount of gel used I think I have obtained a very generous amount of DCM.(no exact measurements yet sorry)
When I have washed it and dehydrated it, I will do a boiling point experiment to confirm that it is pure DCM (as NBK did).

I also have some problems extracting the HNO3 from the DCM!
I could boil off/distill the DCM from the HNO3 at 40-50 deg C, BUT how will I know when all the DCM is gone?(I ain't going to sniff it) :)
AND the HNO3 will still evaporate off when doing this which could leave you with a more dilute acid than anticipated in the patent!(I don't want to do nitrations with the DCM still present because I can't be sure how much acid I am using)
NBK's idea of freezing out the HNO3 is MUCH better but dry ice is a pain in the ass to get and impossible to store at home(?).
I am very interested in this because I FUCKING HATE DISTILLING HNO3!!! AAARRRHHHH!!! :mad:
Has anyone got any better ideas of extracting the HNO3 from the DCM? :(

Boiling pt experiment coming soon!
HNO3 solvent extraction from XNO3/H2SO4 experiment as soon as I receive some new electronic scales (other scales disposed of in a runaway nitration :( )

So has any got any comments on this?
Any magical solutions to removing HNO3 from DCM? :)

C-Ya

[kingspaz]

to purify the DCM from water add dehydrated calcium sulphate, mix it up then filter out the newly hydrated calcium sulphate.
i beleive a possible problem overlooked so far in extraction is that in CH2Cl2, as opposed to CCl4, the chlorine atoms are open to attack by H2O molecules. thus hyrdrolising, CH2Cl2 + 2H2O &lt;=&gt; CH(OH)2 + 2HCl
HCl is gaseous so removed from the equilibrium and according to la chateliers principle the equilibrium will move to the right therefore hydrolising more DCM :(
at what rate this occurs i am unsure bu i imagine daylight would speed this up somewhat by breaking the C-Cl bond.
mongo, for removing the DCM from the HNO3 read one of NBK's posts above.
also i have bought 500ml of nitromers paint and varnish remover but i got the stuff in the yellow can as it states 'free flowing formula' so i thought i'll get this as it won't have that gel shit in it and therefore volume for volume more DCM :) ....haven't had chance to experiment though.

<small>[ September 05, 2002, 04:35 PM: Message edited by: kingspaz ]</small>

[mongo blongo]

kingspaz-I can't find the post by NBK you are refering to? Which method are you thinking of?

[nbk2000]

The one near the top... :rolleyes:

[andreas]

Has someone tested this nitric extraction method before. As I'll be getting 2 liter of dmc and some destillation equipment.I have a corbondioxide fire extinguisher, could this produce enough dryice to cool 2 liters of prechiled(-30 centigrade) DMC+nitric to -55 or beter -60. And after that what best to use a, sintred glass funel or a saporatory funell?

<small>[ September 06, 2002, 10:26 AM: Message edited by: andreas ]</small>

[nbk2000]

Don't waste the extinguisher making dry ice. Save it for putting out the inevitable lab fire.

Dry Ice is cheap...only a dollar or less per pound (US$), get plenty of it so you don't run out. 20 pounds or so should do nicely.

But don't start out with 2 liters of DCM, use a couple hundred milliliters to start. Then work your way up.

Use the sintered glass to seperate out the crystals. Be sure to precool the filter in the chilled DCM mix, otherwise it'll either shatter, or the crystals will melt and liquify, <img border="0" title="" alt="[Eek!]" src="eek.gif" /> thus defeating the whole point of filtering.

You should also try distilling off the DCM, leaving behind the higher boiling point Nitric in anhydrous condition. All glass or teflon, of course, otherwise (using rubber) you're setup will disintegrate/catch fire.

[Mr Cool]

Kingspaz: I don't think hydrolysis will be a problem; the chlorines are very bulky so there isn't much room for a water molecule to get in and attack the C. I'm sure it happens, but only VERY slowly.

[ALENGOSVIG1]

Alot of aerosol graffiti removers contain Methylene chloride.

Could be a possible source.

<small>[ September 07, 2002, 07:44 PM: Message edited by: ALENGOSVIG1 ]</small>

[Trinitrotoluene]

Thanks for the completely uninformative information. :rolleyes:

I hope (for your sake) that your postings rapidly improve...otherwise I don't see much of a future for you here.

<small>[ September 07, 2002, 09:28 PM: Message edited by: nbk2000 ]</small>

[mongo blongo]

It's taking a while to clean this bastard stuff!! I have extracted about 150ml so far and it's still a bit cloudy. I'm sure that all the methanol is gone now but there is some of that white shit which can't be removed by filtering (that's why it's cloudy). I had it in a jar with a layer of water on top and it was left standing for about 24 hours. After this, the DCM layer was crystal clear and the white shit formed a layer between the DCM and water. I tried filtering it (thinking that the white shit was clumping together) but it still came through!
I now have it in a separatory funnel that is stood upright. I will leave it standing for a day or two for the white shit layer to form again and then I will let the bottom layer (DCM) feed out of the drain tip.
TNT- That was a bit pointless.It's already been said! :)
edit-sp mistake

<small>[ September 07, 2002, 09:41 PM: Message edited by: mongo blongo ]</small>

[Mr Cool]

The cloudiness could be water droplets (like you can get when making NG), which would slowly float up to the water layer and form bubbles of CH2Cl2 around the water droplets at the boundary. If this is the case, you could shake up the CH2Cl2 with a saturated salt solution and leave it to settle, then seperate the two layers. This should clear it up.

[mongo blongo]

Yes I thought of that but I am sure it is due to the white shit in this case because of the other layer forming is a solid white substance. It does however it does turn very cloudy when it is shaken but the water separates very quickly. I will make sure there is no water present by washing it with a dehydrating agent.

[andreas]

I was planning to extract the nitric with severall postions of DMC but I think I'll distill it of anyways becouse the method of freezing it out is quite difficult. This becouse you have to keep the mix cooled even when filtering. As NBK said 98% aint nothing to spit at. It may not be anhydrous but this concentration is good for nearly every nitration you could probably desire. With the exeption of maybe HMX and the like. Furthermore considering the low boiling point of DMC it doesn't take a lot of energy to distill the DMC off and with a bit of ice packing of the condenser and the seceiving flask you get a lot of DMC back. And you can reuse the sulphuric from the first step to boot.

---------------
its DCM standing for dichloromethane NOT DMC - kingspaz

<small>[ September 08, 2002, 05:24 PM: Message edited by: kingspaz ]</small>

[nbk2000]

I don't think you'd have to even filter it.

Simply cool it to freeze out the nitric crystals, let settle, then decant off the excess solvent, all while cold (of course).

When it warms back up, there'll be an excess of nitric...too much for the DCM to dissolve, so a layer of anhydrous nitric will form at the bottom, with the lighter DCM floating on top being sucked off with a turkey baster.

:D

Use the decanted DCM for the next extraction.

[mongo blongo]

Boiling point experiment was a success (it boiled at exactly 40 deg C). Next comes the HNO3 extraction from NaNO3/H2SO4 (when I receive my new scales). Anyone done this before?
I am looking for amounts of DCM to use. Does anyone know the max amount of HNO3 that can be absorbed by DCM and will temp make a big difference? I know that I should use several small DCM extractions to get the best yield.
I have not yet decided how I will separate the HNO3 from the DCM but it looks like I may be freezing it out.
I was going to try and calculate amounts to use from the patent in respect to the moles of HNO3 that should be produced and the moles used of DCM. I can't work out how to convert percentages into moles. Can someone help me out on this or has anyone got any preset amounts?

[Boob Raider]

This is really getting pathetic :( . I can get KNO3 or Ca(NO3)2 and one shot drain opener but I can't even find trace anounts of DCM. Home Depot, wal-mart, revy, local hardware stores ..... no one has Cl HC solvents. This is really shitty :mad: .
Can NaHSO4 be used instead of H2SO4 if trying to dehydrate an acid soln. I can buy shit loads of it from liquidation world dirt cheap .... its some sort of concrete etchant. I am not so interested in making acrolein anyways.
So any other suggestions about DCM fishing ? And also reguarding NaHSO4 to dehydrate HNO3. Oh BTW I saw HNO3 and also H3PO4 in a hydroponics store as a pH down soln. Does anyone have any idea on the concentrations as it doesn't say in the can. I am expecting a shitty concentration.

[nbk2000]

If it's being used with plants, it's likely to be less than 20%. Might be worth it though if it's cheap enough.

[mongo blongo]

Boob Raider-
<a href="http://ntp-server.niehs.nih.gov/htdocs/Chem_H&S/NTP_Chem7/Radian75-09-2.html" target="_blank">http://ntp-server.niehs.nih.gov/htdocs/Chem_H&S/NTP_Chem7/Radian75-09-2.html</a>
It has a "uses" part which may help you on your quest. <img border="0" title="" alt="[Wink]" src="wink.gif" />
It also says DCM is liable to explode when mixed with HNO3! Could this be very dangerous? <img border="0" title="" alt="[Eek!]" src="eek.gif" />
I was also reading this page from Rhodium-
<a href="http://www.rhodium.ws/chemistry/aromatic.nitration.html" target="_blank">http://www.rhodium.ws/chemistry/aromatic.nitration.html</a>
It is using the units "mmol". What is this? Is it something to do with moles? Is it possible to convert it to grams? how? <img border="0" title="" alt="[Frown]" src="frown.gif" />

[vulture]

mmol is millimole IIRC, so 1/1000th of a mole. Convert to moles, multiply with molecular weight and reaction coefficient and you have the needed amounts in grams.

[mongo blongo]

Thanks vulture! I know what to do with it once I have it in moles. :)
I haven't got time right now but when I do, I will calculate the amounts and post them here for reference.

[mongo blongo]

Right I have worked it out. The amounts used in the "aromatic nitration" link I posted didn't look right(not enough acid)!
I have scaled up and changed a few things so this is what I think looks right.

NaNO3-85g or KNO3-101g
H2SO4-100g (2g excess)
DCM-500ml
Yield-63g HNO3 (theory 100% yield)

That is a shit load of DCM! I am not sure if that is right! 500ml to absorb only 63g?
what do you think?

[kingspaz]

not sure if this has been mentioned yet but HNO3 and DCM supposedly form an explosive mixture.

<a href="http://www.biochem.okstate.edu/Safety/SafetyMSDSNitricAcid.html" target="_blank">http://www.biochem.okstate.edu/Safety/SafetyMSDSNitricAcid.html</a>

maybe a new liquid explosive :)

[mongo blongo]

Yes I'm a bit concerned about that! Anyone got any ideas about the sensitivity of the solution?

[nbk2000]

Don't worry about it. Nitric acid forms explosive compounds with practically everything. That's why us pyros love it so much. :D

As long as you don't stick a blasting cap in it, you should be fine.

[Korfaction]

Hello everyone, i recently tried to make conc. nitric acid with that method:

I mixed 64 mL of 58% HNO3 and 47 mL of H2SO4 (about those amounts, not very precise), in total number of moles it is equal to those advised on the us patent. I shaked it with 100 mL DCM for several minutes, cooling the flask because the temperature rised, then i let it sit for one quarte. There was a lower orange layer and a upper clean layer. I seperated them and let it cool not exposed to sun for one week (i'm only here on weekends). From the upper layer which smelt DCM before evaporating, there was only a few mL of clean mix, acid but not too much, with a density of about 1.1 so i'm wondering what happened.
I got a few ideas of what could have been done wrong (cooling..) and stay in the beaker, but anyone exactly knows why that easy manipulation failed ?

Thanks all.

[mongo blongo]

You could try to devide your DCM into several amounts and extract them in several amounts and combine all the extracts. You will get better yields from several extractions than doing it all in one go.
How are you measuring the density?
Maybe you should use a bit more H2SO4?
Another reason could be something like I posted above (about HNO3 evaporating off when letting the DCM evaporate off).

[Korfaction]

I mesure density with that archaic method of taking a few mL then weight it. You divide and you get density. The fact is that is not very precise depending on the way you take the liquid but to measure a density of 1.1 instead of 1.5...

Another fact i don't understand is that there was about 5-6 mL of that liquid left, i assume that it was mostly water. But i should have got 20 mL of 98+ % HNO3 so how could all this water came ? condensation ? that would mean it's not so easy to make, precautions, dry air, are needed.

I used 95+ sulfuric acid, and the total molar quantity is the one told in the us patent. And to prevent questions, i used lab grade 99.9% DCM, the other 0.1% is ethanol to stabilize it.

About the several extractions, allowing the patent, one would use about 700 mL DCM to extract 80% of the nitric acid, in the best case. But then one would try to reuse the DCM.

<small>[ September 22, 2002, 04:39 AM: Message edited by: Korfaction ]</small>

[mongo blongo]

mmmm... I don't know why it's going wrong.
Where did the H2SO4 you were using come from? I would use more H2SO4 if there is still water in your product.
I would also try a different method of removing the DCM from the HNO3. Try freezing the HNO3 out with dry ice if you can.
Also when you measure the density, use more than a few ml. The more the better because it will be more accurate. Even better to use a hydrometer (very cheap).

[Korfaction]

Hello, I was wondering today about the water solubility of DCM. It appears to be about 13-20g.
So will the solubility of water in pure DCM be the same ?
Therefore, it theorically wouldn't be possible of getting more than 98-98.5% HNO3. I know it's enough for most explosives, but i wanted to point it out. (And know if I'm right ?)

[nbk2000]

OK, just gone done trying a little experiment. :)

Firstly, some observations on handling dry ice (frozen CO2) and cold baths.

DON'T use rubbing alcohol. It froze into a slushy muck that I couldn't get below -34F, and took forever to do so. It also "smokes" badly, making it difficult to see what you're doing.

DO use acetone. It got below -52F (the lower limit of my thermometer) within seconds, and with virtually NO "smoke".

Wear rubber gloves over cloth gloves. If you get any of the cold liquid on your hands, without the cloth for insulation, and the rubber to keep it dry, you'll get instant frostbite.

Do this in a room with an open window or outside. You may not be able to see it, but the CO2 will build up if you've got enough of it, and smother you. Plus the acetone fumes aren't healthy either.

Now, on to the experiment.

Using a quart sized thermos soda mug, I cooled down a DCM extract made from 3 extractions of an AN/H2SO4 mix, in a test tube immersed in the acetone/dry ice bath.

After a minute or so, needle-like crystals formed. However, the crystals melted within moments after I removed the test tube from the bath, making seperation impossible. :(

I tried taking pictures of the crystals, but they didn't show, so I won't bother posting them.

I think what I'll have to do in the future is use a fritted glass disk attached to a rod, and have that at the bottom of the tube. When the crystals have formed, I can lift out the crystals and immediately dump them into another flask for collection.

Better yet, have two flasks hooked together with a frit in between. Immerse the raffinate mix in the cooling bath, let crystals form, then invert. All the crystals are filtered out, with the spent extractant being collected in the other flask. The two would then be immediately seperated and the crytals allowed to melt for collection of the anhydrous acid.

When disposing of the cold bath solution DON'T pour it, even in little drips, into the toilet or sink. It instantly boils over and sprays all over the place.

Just set it outside somewhere where it can naturally warm up. Somewhere where people won't see white fumes and think "DOPE LAB!" and call the cops on you. <img border="0" title="" alt="[Wink]" src="wink.gif" />

Cost me a few dollars, and I didn't get any nitric out of it, but I think the failure was just as informative as a success. Next time I'll be prepared and likely to be successful in collecting anhydrous via freezing.

[mongo blongo]

NBK- How long were the HNO3 crystals? I ask this because I have a very fine sieve made out of what I believe to be polypropylene (Al would be another choice) which could be used for very fast filtration of the crystals.
I was thinking of keeping all of the apparatus used in one of those ice boxes so that the surrounding environment and apparatus will be as cold as possible.
Maybe if you make a larger batch it would take longer for the crystals to warm up, giving you some more time to separate the crystals.
I was also thinking of using Ethylene Glycol for the dry ice bath.
I am having trouble finding dry ice at the moment so it may be a while until I can post some of my results.
Sounds good though, nice work. :)

[nbk2000]

1/8"-1/4" and very slender.

A fine metal mesh would probably be good since the metal would retain the cold longer, allowing the crystals to be moved before melting.

Also, a larger quantity would last longer, true. I'll have to try a larger batch next time. Now that I know the process works, I'll aquire more source material to make a decent sized batch of at least a few ounces worth of nitric.

I'd go with glycol next time. You'd want something for a bath that isn't going to be giving off any fumes or flammable vapors.

I'm off to try freezing out H2O2 now, before all my dry ice disappears.

[zeocrash]

the other week i Purified DCM from nitromors paint stripper.
the process was as follows:
250ml of nitromors was added to a 1L flask. 750 ml of water was then added to this.
The mixture seperated out into 3 layers, the top aqueous phase, the middle white crap phase, and the bottom oily phase (DCM).
The DCM was removed from the beaker using a turkey baster and placed in a 500ml beaker. Concentrated sulphuric acid was added until all the water was removed from the DCM (untill the mixture stopped boiling and bubbling). the DCM, this time forming the top layer was again removed using a turkey baster and bottled.

[mongo blongo]

It still won't be pure mate. :) Try putting it in the freezer and you will see what I mean. I have found that if you freeze and filter a few times then distill and then mix it with conc H2SO4 (carbonizes the more hard to remove petrolium distillates) and filter ,then freeze and filter again, you will then quite pure DCM. Well that's the best method I could come up with and it's a lot of work. I would wlcome any quicker methods. ;)

[senjoronie]

I purify DCM from paint remover by fractional distillation. It's still a somewhat involved process, but it's easier and safer than the ones mentioned above, since it doesn't have anything to add or any water or acid mess to deal with. It's helpful if you have a glassware set capable of it, but if not then build yourself a distiller (search for that info).

I use Zar brand paint and varnish remover, which is 91% DCM by weight. The first step is to distill quickly through a Vigreux or other simple column (a hollow, unpacked tube is fine) to remove all the thickener junk and most of the toluene. There will be a lot of bumping as the thickener deposits on the bottom of the boiling pot and traps superheated DCM gas pockets, so don't use too much heat. The column really only serves to prevent the thickener from being blown past the still head and getting into the distillate. Your setup should allow access to the boiler so that you can dislodge the buildup periodically. Collect the crude distillate, but don't process it until you've distilled all the paint remover you were planning on, since the later distillations require an equipment change. Monitor the vapor temperature throughout the distillation; when it reaches 45°C you're finished.

The second and any subsequent steps should be done through a packed fractionating column or a Snyder column, and run fairly slowly. Allow about 6 hours to distill 500mL. Collect the distillate and evaporate a small sample of it; if there is any residual odor of toluene then you need to distill again. This will result in very pure DCM.

[mongo blongo]

It's quicker to leave out the first distillation, if you mix it with water, that will separate the DCM from the thickener and remove the methanol. Fractional distillation would be a good way to go after that but most people don't have the equipment or time to run it for that long. I see there are a few different formulas for DCM paint stripper, one I have experimented with did not contain toluene.

[vulture]

BTW, use as less grease on your glass joints as possible, because DCM leaches the grease straight of the joint and vaseline seems to be volatile when mixed with DCM... :(

To make a long story short: I had a nice layer of vaselin floating on top of my DCM. :mad:

[nbk2000]

When dealing with solvents that can dissolve joint grease, don't use it.

Instead, take a small strip of teflon tape and place it in the joint (leaving a little bit overhanging), assemble your pieces, then wrap the shit out of the joint with more teflon tape. The joints are able to bee seperated, no nasty fumes escape, and nothing contaminates your honey. ;)

Learned this trick the hard way. :(

[vulture]

Trouble is, I bought a pot of something that's supposed to be Teflon grease, turns out it's already attacked by dilute HNO3! :mad:

I was expecting it to happen, therefore I only used a tiny little bit, but to no avail.

I can't seem to find a decent source for pure Teflon tape in Belgium. Either way it's Teflon with 50% other crap or it's bloody expensive.

[zeocrash]

doent plumbing shops sell teflon/PTFE tape. i know the DIY stor i work in does.

[FrankRizzo]

I've found a solution that's not really OTC, but not incredibly hard to procure either. Google a source for "Glindemann Sealing Rings." They're a thin, little PTFE ring that slides onto the male portion of your ground-glass joint and seals it VERY well. They're much cheaper than those Teflon sleeves, and seem to work just as good or even better. I got mine from UGT; 50 rings for about $40-shipped.

EDIT: They also let you use keck clamps, whereas the telfon sleeves make the joint too big.

[nbk2000]

You can find pure PTFE plumbing tape in hardware stores. Used to seal pipe joints. If it's not snow shite, it's not pure PTFE.

Zeo...the I/i capitalization rule applies to you too. ;) You might want to start capitalizing the beginning of your sentences too, while you're at it.

"Teflon" grease is just teflon powder suspended in a petroleum-based carrier. Not at all immune to chemical attack. :(

[jimmyboy]

I have looked at the patent and it looks like a reasonable extraction - has anyone gotten a good yield out of this method yet?

[Dave Angel]

I have finally gotten sick of NOx from standard distillations of nitric acid, so I decided to look into the DCM method.

I can get hold of some lab supply DCM but I'd rather get it OTC if possible, so I bought some Nitromors, the yellow one to be exact. I chose this as it was cheaper than the green one and sounded and felt much less viscous when shaken.

It turned out to be colourless and of low viscosity. I mixed 100mL of it with 300mL of water in a separatory funnel and shook them. The result was a suspension of small fluffy white blobs (dia. 1 - 2mm) which would not separate into 2 or 3 layers as some have reported. Some kind of wax had precipitated and was containing the DCM. Adding water first is obviously not an option with this type of Nitromors.

Instead, I gently distilled some straight paint stripper into a flask equipped with a reflux condenser as the only opening to the atmosphere. The residue, left to cool, congeals into a soft waxy goo (for want of a more scientific term). The distillate was washed in portions with two lots of double its volume in water, and the DCM layer was run off into a flask and stored in the freezer at -20C. No volumes or percentage contents of DCM as yet, this was just a qualitative experiment.

I've just checked the flask and noticed that something has precipitated out of the DCM, possibly some light fractions similar to the wax left in the heating flask. Mr. Cool reported something like this I see, though what I'm concerned about is that some may still remain in solution. I shall check the density after filtration tomorrow and if it indicates other than fairly pure DCM then a final fractional distillation before drying with MgSO4 may remove it.

Any other suggestions as to how to remove this final impurity if any of it remains?

[Edit] It doesn't look like the impurity is going to be a problem. After filtration at -20C the precipitate was removed. It's important to remove the filter paper and scrape off the precipitate before running more crude DCM through though, as it melts very quickly and can get carried through.

A calculated density of 300mL gave 1.31(4)g/cm3 with the literature value being 1.316g/cm3. This was however whilst the DCM was still cold. A weighing of an amount in a volumetric flask at 298K would give a more accurate idea of the density as I have no hydrometer in the correct range.

It seems pure enough for me though. I'm going to extract the rest of the DCM from the paintstripper and dry it with anhydrous MgSO4, at which point it should be good enough to make some of the elusive white anhydrous nitric acid.

[nbk2000]

OT:

Zip-strip, a DCM based paint remover, will apparently remove the dye used in dye-bombs by banks, from the money that's been contaminated with it. :) :D

[Dave Angel]

That being the case, I wonder if DCM can be used to remove the dyes used in those foam/dye defense sprays. Washing my face with DCM doesn't sound too appealing so perhaps a solution of DCM in alcohol would be less aggressive towards the skin and still remove the dye. Still, if it was a choice between being identified by the dye and subsequently locked up, or walking around with a bit of a sore, red face for a while I think I'd choose the latter.

[nbk2000]

Makeup hides many sins. ;) seriously, you'd NOT want to put DCM in any concentration on your face. It'll pull all the oils and fats out of your skin, making it crack and blister something fierce.

Besides, if you're not out trying to "catch" a date ;) on saturday night, you'll not have green dye on your face, right? :D

Reminds me of a joke:

Q: Why do niggers cry after sex?

A: Because of the mace! :p

[Dave Angel]

Tell me about it... I've managed to get a splash on my hands now and again and it chaps them like acetone but worse. I hope I won't be getting any of that foam on my skin anytime soon, if I was going out to "catch" a date I think I'd profit from a trip to The Hive first. :D

Anyway, I finished the processing of my Nitromors and got 3300mL of DCM (out of 5L). This indicates a 66% v/v content, but as some of it was lost in attempting earlier processing (though some of that was recovered) it's more likely to be closer to 70%. This is like Mr Cool's Nitromors, so it's likely that it's a standard 70% DCM with other ingredients to give it different properties for different jobs.

I had something like 800mL of a 50/50 by volume mix of nitric and sulphuric acid that I gave up on distilling normally. I shook this in 8 equal portions with 100 - 150mL of DCM each time in a separating funnel (frequent venting was needed!), and recovered the left over sulphuric acid which, according to the patent, should have plenty of nitric acid left in it.

The DCM/nitric acid is sat in my still now, with a water bath at 50C providing the heat. For the first hour or so there was plenty of NOx around in solution which worried me slightly, but it's now cleared up and the DCM is just a bit yellow. It should take a while to remove all the DCM but the results (I hope) will be worth it.

As a side note, I have quite a lot of soft wax left over from processing all that paint stripper which should be usable in ANWax.

[Mumble]

I've been experimenting with this method too. I can definatly vouch for the burning from DCM on the skin. Made the mistake of using shitty gloves, and they didn't hold up well.

The MSDS (http://www.starbronze.com/pdfs/720.pdf) I got from my paint remover, Zip-strip coincidentally, claimed 80% DCM. From 1 pint(453mL) I got 150mL after purification, a little more that 225mL before purification. I found a purification proceedure in a chemistry book I have. Wash with concentrated Sulfuric Acid, wash with concentrated (bi)carbonate solution, and dry over CaCl2. The acid removed all traces of waxy solid. I think the waxy solid may be the mineral spirits. As with most things, I expect the yield to increase if I used more product. From 1 gallon, I would hope to get 2.5L. Having a separatory funnel would increase the yield too.

I have a slightly yellow DCM solution right now, after attempting to extract .5 mol of nitric acid from Sulfuric and KNO3. I added urea to attempt to destroy the NOx, but instead ended up with Urea Nitrate and the same yellow. Once it stops raining I will distill the DCM off. During a test, I noticed that as the DCM was boiled off, two layers formed. I took a small sample and placed it in a test tube in warm water. I'm going to see about finding the solublility of nitric acid in DCM, so a more accurate amount of DCM can be used.

[Dave Angel]

It doesn't even matter if you have nitriles, DCM seems to eat through them in pretty short order, good for splash protection only really. It doesn't help matters when you have nitric acid in the DCM at times either.

Even at 50C, in my limited experience with it so far, you start to get a definite reddening of the DCM/HNO3 as you have almost removed all of the DCM. Perhaps lowering the temperature even further could prevent this as the last of the DCM is distilled off, but then you might just end up with the remaining DCM refluxing in the heating flask. Gentle heating of this in an open pan would be the solution to this, with the disadvantage of lost DCM.

I've decided to go half and half on this, if you like. I'm collecting all of the DCM/HNO3 I have reduced down and once I have enough to make it economical I plan to buy dry ice and extract the nitric acid that way. I've no idea how long it'll store in an insulated box or how much it costs as yet.

Mumble, I've made a couple of useful observations whilst doing this which may help you.

Firstly the DCM will easily distill over without boiling (ie. no bubbling in the flask) which should limit decompostion and nitric acid carried over. I use a hotplate to heat my water bath and it holds quite well at around 48-50C w/o thermostatic control via a probe (which I do not have).

Secondly, with the first distillation I did, I noticed a second small layer at the bottom of the heated flask quite early on. I'm pretty sure this is sulphuric acid (it's quite viscous) which did not separate properly (ie. I didnt leave it long enough). Now, once I have all my extracted HNO3 in DCM I put the whole lot back into the separating funnel (certainly a useful piece of kit) and give it a good 15-20 mins so that the remaining H2SO4 can separate out. Was your sample of the other layer miscible with the warm water though?

Good luck with your experiments.

[Bugger]

Dichloromethane, like other volatile chloro- and bromocarbons, is a dangerous liver toxin in large doses. "Glue-sniffers" who inhale it (or paint-stripper) and similar substances are also in danger of brain damage through its getting into the bloodstream through the lungs.

It is also very corrosive to practically all plastics.

John W.

[Dimroth]

Doesn't glue usually contain methylacetate as a solvent? According to my references you'd need serious exposure to suffer from any effects.

I

[Mendeleev]

In the USA, Jasco's paint and epoxy remover is around 82% methylene chloride, and can be bought at either Lowes or ACE.

http://www.jasco-help.com/products/prod_rem.htm

They have msds's for all their products, and the graffiti remover has ammonium hydroxide, so it's likely that other brands like the aircraft remove that nbk got use it as well. Do not buy any strippers by Crown, they are orange. I attempted to wash the crown shit straight out of the can, and it separated into the three legendary layers, but the bottom layer was still orange. I suppose you have to distill first, then wash to get rid of the methanol, then dry with CaCl2, filter, and redistill to get a relatively pure product. Also, the crown stuff conatians toluene and acetone in addition to methanol.

[bobo]

Twice I made con. HNO3 this way. The first time, I used distillation until slightly red color appeared to get rid of the DCM. Apparently, the boiling temperature rises quite a bit even at moderate DCM concentrations, as the product contained a respectable bit of DCM.

The screwthread stopper I used, by the way, was no inhibitation at all for the DCM to happily evaporate from the bottle, in a few months of disuse.

Similarly, using no distillation at all, at 20 degrees, it takes about a week for the DCM to leave the mixture if there is no stopper present. Although the red gases appear of their own in concentrated solution, so I do not suggest storing this mixture for long. Vacuum distillation would be best, though a cold trap (liquid nitrogen is safe) is required if you want to use a membrane pump.

Using nitrogen cooling, I made the nitric acid freeze out and was slightly disappointed at the resulting crystals. The density of this acid was about the same as the acid obtained through low temperature distillation.

However, in all cases, the acid did not heat to the touch when adding an equal amount of concd sulfuric acid (indicating near anhydrous acid), although a double layer may appear if there is a lot of DCM still left. This is no problem at all for me, since DCM does not harm most nitrations one bit, and in fact is a good addition for the more sensitive nitrations.

One thing about paint stripper: there is now a green type of paint stripper as well, containing NO DCM, in the european hardware stores. This may or may not always be written on the can, but if it is an environmentally friendly paint stripper, you probably won't find any DCM.

[The_Rsert]

My local paint store sells anything I need from it.
Waterfree isopropyl alcohol, acetone, 24% hydrochlroric acid, 25% liquid ammonia ethanol and ether, styrene and methanol if you will ask for it but no DCM.
When I asked a clerk of the store for DCM, she told me that chlorinated hydrocarbons are principle forbidden to sell in Germany.
Is that true?
Does it give some law-vacancies/law-openings or any legal reasons to get the DCM?

[FUTI]

About CH2Cl2 toxicity discussed here I can add only that it is considered cancerogenic in such extent that it is removed from decaffeine coffee production where it was used for caffeine extraction. Only chlorinated compound that can be found OTC is trichloroethylene AFAIK.

[Mumble]

No, you can get a handful of chlorinated solvents OTC. I can't speak for Germany specifically, but often times it is not in a pure state. In the US DCM can be retrieved from "Zip Strip". It supposedly contains something like 80% DCM, but I don't believe it. Extraction of the DCM is fairly easy. A simple distillation and wash with water will remove everything leaving you with nearly pure DCM(I dry it of course). I've heard of Tetrachloromethane being available in starting fluids. It's also in some hobby glues(very low percentage though). There is chlorobenzene in a certain type of herbicide(Monsanto Lasso Herbicide).

Basically it's just a matter of looking, and willingness to extract. Where there is a will to get it, there is a way.

[Centimeter]

I mixed 150ml 70% HNO3 and 150ml H2SO4 then added about 300ml MC in 3 portions. I obtained about 50ml of acid. Near the end of the distillation the HNO3 decomposed A LOT. I kept the distillation between 40 and 43*C. Why did it decompose at such low temps? There was some sort of solid that formed in the HNO3. I put it in a separatory funnel and got out all of the solid. Upon titrating the acid, I found the concentration to be ~71%. What the fuck is up with that? Granted the MC was contaminated with something. Or perhaps there was an impurity in the H2SO4 drain cleaner, that was nitrated? BUt 71% from 70%. Any thoughts on what's going on?

[zambozan]

Hallo to all,

I've found a solvent in a home-market which is composed 50% of trichloroethylene and 50% methylene chloride.
It costs € 2 for 2 L. This seem to me not that expensive.
How about using this as a OTC source for methylene chloride?
Can be distillation for separe methylene chloride from trichloroethylene?

Hope that I've helped.

[nbk2000]

What's it called? :rolleyes:

[Pb1]

I don’t think the trichloroethylene would be a major problem, as it would just boil off with the methylene chloride after extraction.

[FUTI]

It will be a problem with trichloroethylene...but I'm not sure of its size. NOx if(or better said almost allways) present can make number of side reactions if that CH2Cl2 is contaminated...I didn't read the papers attached to better then chlorpicrin thread but this can lead to something similar if my guess is right. Conditions of extraction or reaction (if that is what you want) are still blurred to me, but I will try to find something to report.

[Elucifer]

me, i go down to "-------- Plastics" and ask for a 4 litre container which is used for sealing/fusing lexan, they hand it to me, i hand them $20 and i go back to work! it is remarkably pure, it is used where ever plastic retail displays are made.


E-Lucifer

[Sworn]

I think the solvents are slight volatile and difficult to separate when distilled only one time. A useful separation will work on the melting points.

trichloroethylene, melting point around -86 °C
methylenen chloride, melting point around -95 °C

Might that work, trichloroehylene decompose at around 110 °C and methylene chloride at around 120 °C.

First distill the solvent above the boiling points to clean them from residues and decompose the trichloroehylene. Reflux the destillate between 110 and 120 °C for an hour and distill again. The distillate should be useful.

It`s a pity for the trichloroehylene.

Any thoughts ?

++++++++++++++++

Yeah...in the future, use more paragraph breaks in your posts. NBK

[rayman]

Nbk How did your experiments with this go ?

[Sworn]

In my opinion, methylene chloride is difficult to make. Maight a decomposition of a small quantity of nitromethane combined with a chlorination gives various results of a solution of methylene chloride and chloroform.

Such a technique is used to produce ammonium nitrite.

However, anyone may find something more to cool the distillate below -63 °C to separate the chloroform.

[Nitric-producer]

After reading the above about ease of concentration of Nitric acid, I decided to get myself some paint stripper. Mixed with water and seperated out the DCM. I bought the cheapest stuff available and didnt get that much DCM. Next time will try a brand name. Anyway does anyone have any more progress on calculating how much Nitric will dissolve in this? Need to find some dry ice...!

[plutobound]

Has anyone actually been successful at extracting useful quantities of Nitric acid from Dichloromethane (DCM) using the freezing method?

I mixed 527g of 70% HNO3 with 821g of 96% H2SO4 (I need a significant amount of anhydrous HNO3). Thoroughly agitated the mixture with 4 liters of DCM (in one liter portions), separated the raffinate from the hydrated acid using a separatory funnel.

I then cooled the mixture to -70C.

There were a few small crystals in the flask, but even without loss from transferring, the yield was so low as to be useless.

I titrated the raffinate with KOH to verify that there was a significant quantity of HNO3 present (there was).

So now I am distilling the DCM/HNO3 mixture and recovering the DCM for reuse, but the freezing method sure would be simpler.

[PapaMuffin]

Long-time browser of the forum and roguesci.org, first time poster. I know that as a n00blet, I shouldn't be starting my own thread, but I happened upon this the other day and thought that it would look quite nice in this particular forum.

http://www.freepatentsonline.com/3981975.html

In effect, the guy posits that you can get a yield of around 50-60% anhydrous HNO3 by making a 47:53 solution of 95-98% H2SO4 and 70% HNO3, respectively, then performing either a series of 100mL extractions using methylene chloride, or one big extraction (which will, as is generally the case in liquid extractions, produce a lower yield). Anyway, it seems like a less cumbersome method than distilling it to ~90%, then bubbling air and urea through it. You just have to be willing to shell out the cash for the additional reagent (methylene chloride), which seems comparably inexpensive.

Has anyone tried this, or has the equipment and time to try it?

+++++++++++++++++++

We don't encourage noobs to start new threads because they usually shit the bed... They rarely have the common dog fuck to search the forum properly for existing threads...

Merged...

[stupid939]

OK, there has been a discussion on the subject of concentrating nitric acid using DCM for quite some time now, and there have been successful results. What I want to know is if anyone here has actually used the anhydrous nitric acid in DCM solution to nitrate any substance, particularly hexamine. I would assume you would cool the solution, add hexamine (and possibly ammonium nitrate for better yields), heat the solution (possibly driving some of the DCM off, and then cooling and collecting the RDX (if it is not soluble in DCM).

I know some have discussed this, but from my searches (for hours) I have not found any claims. I believe nbk mentioned it awhile ago, and from what I gather, the DCM will not affect the nitration of a substance.

Maybe I will have to be the guinea pig on this one when I find the time.

[Alexires]

stupid939 - Do you know what the reaction method is? If it involves the nitronium ion, you might not be able to do it without an acid in there to form the nitronium ion. I don't have a copy of urbanski here, so I can't look for you, but just have a look and see how the reaction method looks.

[stupid939]

My original question came from this:
I think i remember reading a while ago in the patent for this that the nitric acid with the methylene chloride still present in the acid, can be used for the nitrations without the methylene chloride interfering. Would this work for the prodcution of RDX? All you would need to do is mix the nitric and sulphuric acid, add the methylene chloride, suck off the sulphuric/water layer, and PRESTO! Acid for RDX manufacture!
I have also read this in some of the nitric acid extraction technique patents. Anyways, to re-state my idea:

The AN could be left out, and the synthesis proceed as if only using nitric acid and hexamine. So, you would have a solution of nitric acid and DCM. Hexamine would be added to the solution, keeping it at a low temperature. This would then follow the basic procedure and the temperature would be held at 55°C for several minutes (and the solution would likely boil). Then it could cool, and the RDX would precipitate. It could then be filtered, and the DCM possibly re-used.

This is all of course if RDX in insoluble in DCM (which I could not find any data on).

[Alexires]

Solubility: One gram in 25 ml acetone; slightly soluble in acetonitrile, methanol, ether, ethyl acetate, glacial acetic acid; practically insoluble in water: carbon tetrachloride, carbon disul-
fide

If this is correct, I would assume that the solubility of RDX is maximum around a dielectric constant of k=20.7 (that of acetone). Hence, something like dichloromethane (aka dyke) which has a k=9.1 would be less than 1g/25ml, but more than slightly soluble, I would say.

This is due to dichloromethane having a k lower than acetone, but above things like ethyl acetate (k=6), carbon tetrachloride (2.2) and carbon disulfide (2.2). The other side of the spectrum are things like water, methanol and acetonitrile which have a k value significantly above that of acetone. I would expect glacial acetic acid to have a solubility similar to that of acetone, but that isn't give in the above and has been considered "slightly soluble".

Hence, I would say that using DCM would decrease yield slightly. Then again, if that is all you have, then that is all you have. I'm sure that by lowering the temperature of the DCM when you are done, you would be able to get the extra RDX out. If you are planning to reuse the DCM (I don't see why not) then your second batch should have an expected yield.

[fluoroantimonic]

A problem that I can with this scheme is that hexamine may precipitate as insoluble hexamine nitrate as soon as it contacts the DCM-HNO3 solution. This may inhibit further nitration, I don't know. You'd just have to try it and find out.

It sure would take a lot of DCM, about 4 liters of it to dissolve the 500g HNO3 needed to nitrate 50g hexamine at a high yield (according to COPAE). That is unless having the DCM present would reduce the needed amount of excess HNO3. Again, just have to try it and find out.. With 4 liters of DCM you might end up dissolving a pretty good portion of the RDX.

"For RDX, though, extraction of a 400-mL sample (of RDX dissolved in water) with 20-mL of methylene chloride resulted in only a 60% recovery of RDX (Leggett et al., 1990). Using salting out extraction with acetonitrile, however, recovery was 96%..."

This tells me the solubility of of RDX in DCM is probably low. Hard to say how low, but I would bet lower than 1g/100ml. To decrease it much further you could add something low boiling like erthylene glycol to precipitate it from the DCM, then distill off the DCM.

[stupid939]

Thank you for that information Alexires. Like fluoroantimonic said, the only way we will really know is if someone tries it, but the information you both provided gives me a little hope that it may work. When I have the time, I will test this procedure and report my findings. This would make for a much simpler way of making RDX in my opinion.

[FUTI]

If 20 ml DCM extracts 60% RDX out of 400 ml water solution then I would say DCM is good solvent for RDX. Also watch out how do you perform acetonitrile version of that experiment...AFAIR acetonitrile is prone to acid induced explosive polymerization . SWIM (no not me) was doing some nitration experiment which involved acetonitrile as solvent and that went wrong... yellow T-shirt kind of wrong stuff ;-). Reference he was doing experiment was reliable, other components I eliminated as the one I can't imagine to do something funny under those conditions, I'm certain that experimenter is more reliable then myself and didn't made some error so only thing that was left was that he used acetonitrile that made problem. I'm kind of surprised that reference didn't noted that problem...I bet it doesn't occur often only when acetonitrile is contaminated with other stuff like acrylonitrile etc., so if you don't purify your solvent you play Russian roulette ... which batch did I get today?

[fluoroantimonic]

Heh... well considering there might have been a whole 5 or 10 milligrams of RDX in that water, I don't believe DCM would be that great of a solvent. Hell acetonitrile only dissolves about 1g per 20ml IIRC.

And nobody is recommending acetonitrile as a nitration solvent, I doubt it would be near stable enough, and besides you wouldn't want it to be a good solvent for your product anyway.