[img:4a8f30d074]http://img502.imageshack.us/img502/1559/img1488mediumch9.th.jpg[/img:4a8f30d074] [img:4a8f30d074]http://img232.imageshack.us/img232/2135/img1489mediumos6.th.jpg[/img:4a8f30d074] [img:4a8f30d074]http://img514.imageshack.us/img514/7557/img1490mediumvd6.th.jpg[/img:4a8f30d074] the above is the remains of some evaporated naphtha, was evaporated with a fan blowing over it just to speed up the process and see what would be left behind, the specks are dust, but there clearly seems to be some left over film/residue... so is this brand not ideal due to the uncleanliness of evaporation? its in the metal container so i was wondering if there might be some anti rust agent in there, possibly in the residue as well not sure about any of this as im very new, so looking for some information or advice, thanks alot

It's hard to tell from the pictures, but most people would probably say don't use it if there's residue left behind. I'm not real sure what the residue would even be though. I use another hardware store's brand of VM&P, but i've never actually evap'd it to check for residue. Never had any problems though, so i'm wondering what the leftover residue even consists of. Anyone know?

I've got a friend who's used Ace brand VM&P Naptha a few times now with no complications. When he did the evap test upon acquiring the solvent there was no visible residue left over. I wonder if the fan blew some crap into the mix to cause the residue, my buddy let the glass plate air-dry when he did his test. The volume of naptha tested was ~25ML so it evap'd pretty quick.

thanks sippyj, exactly the kind of post was looking for, test will be done again sans fan next time

SWIM uses the same brand with no problems. However he now uses the Naphtha for precipitation only and uses Xylene or Toluene for when he evaps.

is toluene better than naphta? Evaporates quickly?

[quote:a145fa5100]is toluene better than naphta?[/quote:a145fa5100] Not for normal extractions. Toluene will pull the red-colored "dark DMT" as well as the nn-DMT.

And that being said, despite all of the purists, it's very interesting to do an extraction using Toluene or Xylene instead of Naptha for exactly that reason. The effects of spice pulled in this manner are, IMO, second to none. Amazing. Different. But yeah DZ's right... Naptha is more selective and will pull a more pure yield, so to speak.

[quote:392365b41d]the above is the remains of some evaporated naphtha, was evaporated with a fan blowing over it just to speed up the process and see what would be left behind, the specks are dust, but there clearly seems to be some left over film/residue... so is this brand not ideal due to the uncleanliness of evaporation? its in the metal container so i was wondering if there might be some anti rust agent in there, possibly in the residue as well not sure about any of this as im very new, so looking for some information or advice, thanks alot[/quote:392365b41d] As long as you freeze precept the crap will stay in the solvent. If you want to use it for evaporation you will need to distill it before use that will remove any residue that will not evaporate. M.V.