Sciencemadness Discussion Board

Acquiring Toluene from Contact Cement

radiance88 - 19-12-2014 at 10:51

Greetings mad scientists!

I've been interested in acquiring some toluene as use as a solvent for some time now.

Unfortunately since my country has some uber-draconian drug laws, they've actually banned the retail sale of toluene here, and ordering it may possibly cause Big Brother to come knocking on my door. The products that must absolutely contain it have mustard oil added into it as a sniffing deterrent.

Thus, I've found that I must become creative if I wish to obtain this useful solvent.

Doing some investigation, I've found that a certain locally sold contact cement contains toluene - more than half of it percentage wise in composition.

My understanding is that the toluene is a solvent for the adhesive agent and allows it to be spread properly - the toluene will start evaporating almost immediately upon exposure to the air.

My idea for obtaining toluene then is to separate it from the contact cement.



The MSDS for the material reads its composition is as follows:

Toluene - 50-60%
Naphtha(petroleum), hydrotreated light - 20-30%
Mustard Oil - 1%
Non-hazardous Ingredients - Rest



My question is the following: how would one extract the toluene from this contact cement?

I don't think allowing the material to touch glassware would be a very good one.
I'd also think that the toluene fumes would need to be run through some sort of condenser, as it evaporates so readily.


[Edited on 19-12-2014 by radiance88]

gdflp - 19-12-2014 at 12:36

https://www.youtube.com/watch?v=DT35x-2aR6g This might be helpful. It's a different solvent, but the idea should be similar.

Wizzard - 19-12-2014 at 13:23

I wonder why toluene is so hard to get, now - What drug is it used in making? I'm glad I purchased some in bulk a while back. Thaaaaaank you, Ebay!

careysub - 19-12-2014 at 13:26

I would try the distillation-from-the-can as shown in the video, stopping at 110 C, when the toluene should have all come over.

The allyl isothiocyanate (the active compound in mustard oil) boils around 150 C, so this alone may remove that effectively.

Fractional distillation would help separate other naptha hydrocarbons from the toluene, but some may be difficult to remove entirely.

FWIW: allyl isothiocyanate is somewhat soluble in water, and hydrolyzes in alkaline aqueous solution rapidly (half-life 15-20 min at pH 8). An alkaline water wash might be effective in purging any residual compound:
http://ucanr.edu/datastoreFiles/608-513.pdf

radiance88 - 19-12-2014 at 15:03

Quote: Originally posted by Wizzard  
I wonder why toluene is so hard to get, now - What drug is it used in making? I'm glad I purchased some in bulk a while back. Thaaaaaank you, Ebay!

In my particular country the toluene base itself is used as a drug, mostly by the homeless and extremely poor. Supposedly sniffing it staves off hunger, and leads to hallucination. As one would imagine, it's not a very healthy thing to do, and the Wikipedia article on toluene concurs by saying that it also does some very serious nervous system damage.

The toluene itself isn't used as a reactant or catalyst but a solvent for purification/extraction for different drugs. Unfortunately, it's not widely understood here that there are many uses for solvents outside of illicit drug manufacture. Hence the completely insane laws here where virtually all pure forms of solvents have been banned and/or regulated. Some people have been busted here just for selling a measly few liters of acetone.
Quote: Originally posted by gdflp  
https://www.youtube.com/watch?v=DT35x-2aR6g This might be helpful. It's a different solvent, but the idea should be similar.

Thank you for mentioning this, gdflp.
Quote: Originally posted by careysub  
I would try the distillation-from-the-can as shown in the video, stopping at 110 C, when the toluene should have all come over.

The allyl isothiocyanate (the active compound in mustard oil) boils around 150 C, so this alone may remove that effectively.

Fractional distillation would help separate other naptha hydrocarbons from the toluene, but some may be difficult to remove entirely.

FWIW: allyl isothiocyanate is somewhat soluble in water, and hydrolyzes in alkaline aqueous solution rapidly (half-life 15-20 min at pH 8). An alkaline water wash might be effective in purging any residual compound:
http://ucanr.edu/datastoreFiles/608-513.pdf

That distillation-in-the-can method truly is ingenious, I never would have thought of it. I was too busy trying to figure out how the hell should I construct an apparatus to place the contact cement in.

I'm curious if anyone here has already attempted something similar to this though.

Since solvents are much easier to obtain in the US, I would have to assume that this particular experiment would likely have been done by others out of pure curiosity rather than need like myself.

careysub - 19-12-2014 at 15:17

Quote: Originally posted by radiance88  

I'm curious if anyone here has already attempted something similar to this though.



If you a wait a week or two I am going to do a couple of from-the-can distillations of solvents with a rig I already have set-up, a "red neck rig" PVC fractionation column. I'll post pictures and notes when I give it a go.

Pure solvents aren't as readily obtainable in the U.S. as they were even quite recently.

The cheapest organic solvent I can buy at the hardware store here in Southern California is a ethanol/methanol (45/55) mix, which I intend to fractionate into pure ethanol and methanol for a fraction of the cost per liter of purchasing either of them.

I also have DCM paint stripper to distill, like the video.

And I plan on stripping a low boiling fraction from the winter-blend gasoline on sale cheap right now for petroleum ether.

[Edited on 19-12-2014 by careysub]

palladium8 - 24-12-2014 at 13:32

What country do you live in that has laws like this that you can't buy toluene? Singapore? Middle East?

macckone - 24-12-2014 at 22:51

If you are going to distill something with light naptha
to get toluene, I would suggest gasoline.
It is going to be much more cost effective than
contact cement.

Oscilllator - 25-12-2014 at 00:29

Quote: Originally posted by radiance88  

I'm curious if anyone here has already attempted something similar to this though.

I have distilled dichloromethane paint stripper directly from the can with success. I have one very important piece of advice for you:

Make sure you tip 1/2 of the cement out first into a jar, distill, then add the rest

If you don't do this then it's liable to foam up the distillation apparatus, up the stillhead, down the condensor and get everywhere. I found this out the hard way.

confused - 25-12-2014 at 01:08

Quote: Originally posted by palladium8  
What country do you live in that has laws like this that you can't buy toluene? Singapore? Middle East?


If you're in Singapore, you can get tolulene and other industrial solvents from Horme hardware store. :)

the best i can come up with for acids like HCl would be distiling it from some household drain cleaners that contain 8.8% HCl along with other additives. :(

dermolotov - 26-12-2014 at 22:02

Quote: Originally posted by confused  

the best i can come up with for acids like HCl would be distiling it from some household drain cleaners that contain 8.8% HCl along with other additives. :(

Pool suppliers is the #1 go to place for HCl. Muriatic acid is approximately 31% HCl used to de-lime pools and comes in 4l jugs.

confused - 26-12-2014 at 22:19

im in singapore, all the common mineral acids as well as common bases are restricted to licensed personnel only :(

[Edited on 27-12-2014 by confused]

Muzz1969 - 1-1-2015 at 06:23

If you get universal thinners from the automotive paint section , you will find it is made up of at least 40% toluene and the rest is various ketones. Simple distilation or fraction distilation will give you your toluene.

subsecret - 1-1-2015 at 09:15

Quote: Originally posted by careysub  

...
The cheapest organic solvent I can buy at the hardware store here in Southern California is a ethanol/methanol (45/55) mix, which I intend to fractionate into pure ethanol and methanol for a fraction of the cost per liter of purchasing either of them.
...


This might be a little off topic, but what does your setup look like? How long is the column?

[Edited on 1-1-2015 by Awesomeness]

Dr.Bob - 2-1-2015 at 06:28

Quote: Originally posted by careysub  

If you a wait a week or two I am going to do a couple of from-the-can distillations of solvents with a rig I already have set-up, a "red neck rig" PVC fractionation column. I'll post pictures and notes when I give it a go.


You might be able to distill alcohols in PVC, if they don't contain any other chemicals (which seems doubtful), but most every other chemical will dissolve it, so I would try either glass or copper, those will handle most organics. But PVC being used for handling any chemicals is an accident waiting to happen.

subsecret - 2-1-2015 at 07:44

If you build a copper still, build interchangeable parts like in a glassware set. This way, if you're distilling something with a low boiling point, swapping the condenser is no problem.

radiance88 - 2-1-2015 at 10:21

Quote: Originally posted by Muzz1969  
If you get universal thinners from the automotive paint section , you will find it is made up of at least 40% toluene and the rest is various ketones. Simple distilation or fraction distilation will give you your toluene.


I know that contact cement might be an unusual material for solvent extraction, but my reason for selecting this material is my knowing of what it is made of. The MSDS provided by the manufacturer shows the chemicals that comprise it (or at least a rough estimate).

I've examined pretty much all paint thinner product and brands at my local hardware store, and they never list their contents, while I also cannot find this list online.

So, I should look for a "universal" thinner? Is there any difference between that and acrylic thinner, and any other generic thinner I can find? Or is being a thinner the main thing here?

One concern is - how can we be sure that toluene is the primary solvent?

What also concerns me is that since I am aiming for pure toluene, how will I know it's toluene, when I get it? When I do distillation, for all I know, I may have gotten two or more similar compounds that distilled over with similar color and properties etc.

How would I know that it's toluene that I've gotten and nothing else? If I assume on one hand that I've gotten pure toluene by the first distill, for all I know there might be a decent amount of impurity. On the other hand, I might be distilling and redistilling my product over and over and might have pure toluene already, and be wasting my time.

In doing this extraction (or set of them) aiming for pure toluene, what would I be looking for, and when do I get there, considering that I don't know exactly what the product is made of?

gdflp - 2-1-2015 at 19:21

If you don't have a ground glass distillation apparatus this will be difficult. If you do, then you can redistill it using that, and get a reasonable assurance that you have toluene based on stillhead temperature. You could try putting it in a beaker, then boiling it and measuring the temperature. If it is close to that of toluene's boiling point, that would be reasonable assurance.