polar/non-polar extractions question

when making extractions using this basic method, it's come to my attention that using naptha or lighter fluid for the nonpolar solvent can leave a scum of it's own. does anyone know how to obtain an easy alternative to this, either specific naptha types, other petroleum ether products that are purer, or whatever? i just don't want to end up smoking any of that shit, y'know?

 

You can order pure solvents from a chemical supply house, or order them from the 'net. Of course they will be more pricy. I think it's "reagent grade" but i'm not sure, basically its what ppl use in labs (as opposed to industrial grade).

 

Any OTC solvents you use should be tested by evaporating a sample on a glass plate and checking for residue. Ronsonol or Zippo brand lighter fluid, and Bestine brand rubber cement thinner are all good clean NP solvents in my experience.

The only reliable way to purify solvents like this is distillation. But unless you have the required equipment, this probably isn't an option for you.

 

equipment haha

you better believe it.

 

if you have disstillation glassware then just distill, you can check the various boiling points online via msds and probably a few stickys at www.the-hive.ws under newbee forum or www.rhodium.ws, if not you can use various solvents from the hardware store (vm&p naphta ime is usually pretty clean) like dliss said just do a quick evap. test

 

Rhodium recommends using Coleman Fuel, stating that it's the cleanest OTC solvent.

 

Coleman fuel contains a small amount of a greenish oil, presumably as a corrosion inhibitor. I wouldn't suggest using it for extraction purposes without distilling it first.

Of course, distilling highly flammable solvents is horribly dangerous without proper equipment and knowledge.....

 

Don't use coleman fuel.

Ellis ain't kidding about the green.

 

Wow, a post at 4:20. Yay.

 

ok, i went out and got some ronsol lighter fluid, but it's got heptane in it as well as naptha. ellis, you're the expert, is it still usable?

 

Heptane *IS* naphtha.

"Naphtha" is a generic term for mixtures of low-boiling liquid hydrocarbons. It is generally a mixture of pentane, hexane, heptane, octane, etc. Other names for the same thing are "Petroleum Ether" or "Ligroin".

 

interesting, interesting, that's weird then. i wonder why they'd write contains naptha and heptane?

 

Probably because heptane is the majority constituent. Naphthas are classified by boiling point, which depends on exactly what compounds are in them.

 

Naptha is a light petroleum spirit.
Heptane is one type of naphtha.