Sciencemadness Discussion Board

Ideas for my Naphtha

Takron - 24-9-2011 at 09:35

I have a gallon of naphtha I recently got and I'm trying to think of anything fun, cool, or super useful I can do with it. I'm open to pretty much anything so lets get those ideas flowing.

Bot0nist - 24-9-2011 at 09:56

If it's clean and relatively dry it can be a useful np solvent. This question really belongs in the 'beginnings' section or even the 'short questions thread.'

Do you know if it's paraffinic or heavy? If your down for some hydrocarbon crackin' you can get some useful olefins.

simba - 24-9-2011 at 10:08

Naphtha isn't fun, depending on what you call fun ofc...extracting fun things with it is probably the most 'fun' it can be.

Bad results with naphta

xwinorb - 25-9-2011 at 04:06

I just would like to add to this thread that naphta seems not to work well as a nonpolar solvent.

I have recently tried to use naphta instead of toluene as a nonpolar solvent. I was extracting something from a water + methanol mixture.

Well, toluene extracts this very well, the toluene plus the extracted oil goes to the top.

When I tried to use naphta, it formed 3 layers : naphta on top, watery layer on middle, and one oily layer on bottom, it crashed out and sunk instead of going up with the naphta.

I separated the layers, titrated the bottom oily layer with HCl till neutral and dried it. It formed the HCl salt.

I extracted more from the middle layer with DCM, titrated also, and got a few more grams of the HCl salt.

I did not tried to extract from the top toluene layer, I had the impression most of it recovered already.

I think what has happened is, the methanol left the watery layer and went to the top mixed with most of the naphta. Then the oil crashed to the bottom.

Also tried to add toluene to the separated bottom oily layer, it DID NOT MIXED, stayed as two layers.

The reason I tried naphta is, I can no longer find toluene at my local hardware store. I have just bought 4 pints of toluene at my local chemistry store, paid in cash, a bit more expensive than the hardware kind but OK.

It was surprinsing to me to see an organic substance that is so easily soluble in DCM and toluene to be so insoluble in naphta.

I am in the USA, west coast.

Takron - 25-9-2011 at 06:08

Quote: Originally posted by xwinorb  

The reason I tried naphta is, I can no longer find toluene at my local hardware store. I have just bought 4 pints of toluene at my local chemistry store, paid in cash, a bit more expensive than the hardware kind but OK.



Try the local paint store. They have a mirriad of chemicals and solvents you can get. Usually by the gallon or even 5 gallon bucket. MEK, Acetone, Toluene, even alcohols and other things. If you have a sherwin-williams close I would try there first.

P.S. I guess Naphtha isn't as interesting as I thought it would be. Guess I move on to the Naphthalene then maybe Hexamine. :D

Nicodem - 25-9-2011 at 06:25

Quote: Originally posted by xwinorb  
I just would like to add to this thread that naphta seems not to work well as a nonpolar solvent.

I have recently tried to use naphta instead of toluene as a nonpolar solvent. I was extracting something from a water + methanol mixture.

You can not substitute naphtha for toluene if what you are extracting is a relatively polar compound. Naphtha is in the range of polarity of n-hexane and other alkanes, so it is way less polar than toluene. Compounds that efficiently partition in water/toluene might not partition as well in naphtha unless their logP is quite high (e.g., more than 3). Furthermore, only very nonpolar solid compounds or moderately nonpolar liquid compounds are soluble in naphtha and alkanes. Consequently, you get a triphasic system when trying to extract such compounds from aqueous solutions.

The rules of thumb about extraction solvents and logP have already been discussed in another thread.

Takron - 27-9-2011 at 12:46

My knowledge of organic chemistry is somewhat limited. I guess naphtha isn't as cool as I thought it was.

xwinorb - 27-9-2011 at 13:31

A bried follow up :

Naphta can be used to extract one very known tryptamine, tons of info about it.

Toluene indeed is a much better nonpolar solvent. I have looked for it in a local automotive supply store, they are supposed to have it but my local store don't, and I checked for availability in other stores, same thing. Looks like it is still possible to order it online. I have not tried a paint store yet.

Also, thanks to Nicodem for his post.