In many extractions SWIM used nafta as non-polar solvent, however no it is virtually imposible to get it. The only other solvent SWIM can get is heptane(from gasoline) But here a question rises, what is the ideal temp. to heat the solvent. For nafta is 35-40 celsius. But SWIM has no idea for heptane, help is needed

Have you found out the perfect temp for heptane yet??

Treat it just the same, naphtha or heptane, water bath heating (bain marie style) it to ultra max 40 deg C would be fairly safe.

Just know that it makes gasses and build up pressure in closed containers, sure when shacked then!!!

@Smoker root

When you say "heptane (from gasoline)", do you mean that you are using straight gasoline? Or are you somehow separating heptane from the other contents of gasoline? Pure heptane can be obtained as "Bestine":

https://www.amazon.com/B...er-Cement/dp/B004O7HM38/

If you are using pure heptane, then I've had success treating it just the way I treat VM&P naphtha.

However, depending on what you are trying to do you should in theory be able to heat heptane to a higher upper limit than naphtha, because it's boiling point is higher-- Klean Strip VM&P naphtha is "light naphtha", which is mostly hydrocarbons under 6 carbon atoms, while heptane has 7 (boiling point rises with more carbon atoms).

By the way, why do you say the ideal temperature to heat naphtha to is 35-40 C?

I don't want to answer in SmokerRoots turn but my own take on this is that it is the highest temp without becoming too volatile to handle. A good reference I use is to get it to body temperature at max.

Raising temp is done to max out it dissolving properties. Many people just use room temp and do fine with that.

Using straight gasoline would be a nono, it has a spectrum of components under which potentially additives for performance and storage properties (anti gum).

@Jees

I've successfully heated organic solvents to their near-boiling point in a water bath on a hot plate (with plenty of ventilation of course). I know this creates more fumes, but with adequate ventilation is there a problem? Is there some point at which the risk of ignition spikes, or does it just smoothly increase? For what it's worth, I was just following what's in MIT's recrystallization tutorial.

Regarding solubility properties-- when you mix immiscible liquids (e.g. MHRB tea and heptane), the temperatures of the two liquids will quickly equalize and solutes (e.g. DMT) will end up distributing themselves according to the ratio of the solubilities in the two liquids (this is called the partition coefficient). In general, the solubility of solute X in both water and an organic solvent will go up with increasing temperature. So the effect of raising temperature on partition coefficient, and therefore yield per pull, is not predictable without additional knowledge.

So I'm wondering-- does the heptane/water partition coefficient for DMT generally increase with temperature? This does seem to be the case from my experience (i.e. hot pulls seem to get more DMT but also more impurities), but it would be nice to have some scientific validation.

Assuming the partition coefficient does in fact increase with higher temp for both DMT and impurities, then really there is no one optimal temperature for pulls for any given solvent. You should be able to use any temperature between the freezing point of water and the boiling point of the solvent, depending on how you want to balance three factors:

- DMT yield (goes up with higher temp)
- DMT purity (goes down with higher temp)
- solvent fumes (goes up with higher temp)

Yes there is a threshold dangerous point, the auto ignition point at which the heptane will ignite even without an external igniting source nearby, but is very high and thus not normally obtainable by own actions of heating, so not much of a danger to be that foolish, it's far above boiling point:
Autoignition temperature 223.0 °C (433.4 °F; 496.1 K)
It can however reach that point if spills drop on a halogen stove plate or so, so this intel is not completely void of importance!!

The flash point however is the temp at which vapours will ignite with the help of an external ignition (spark or flame):
Heptane Flash point −4.0 °C (24.8 °F; 269.1 K)
Some literature say -7 deg C

The most practical danger imho is the pressure rise with elevating temp when shaking a closed vessel with heptane or naphtha. Guess how I know
Mind that any spill in that phase likely holds high base pH, no fun splashing with that, the naphtha is least of dangerous if there is no ignition source about to be found, but if there is it potentially ignite the splashes.

When it comes to solubility vs temp, I suppose this is mostly important on a practical scale when doing Re-Crystallizing. For making pulls in a base liquid + non polar solvent imho a room temp vs elevated temp (say 40deg C) will determine how white or yellow your pulled product will be, and accordingly affect the yield. People make their choices freely what they prefer most.
I agree that mixing liquids with different temp (non polar + polar) will equalize temp so fast when shaken that we can wonder if it truly matters to heat the non polar solvent in the expectation to pull more.

On a note, when doing Re-X with a heated heptane or naphtha, I am on a verge to believe that too high heated naphtha might influence the polymorphic states of the deems, that too hot might induce more oily results at the cost of white crystals. I'm not fully sure and would like some feedback if possible.

My 2 cents fwiw

@Jees

Thanks for the info on flash point and autoignition, I was murky on those terms.



Also, depending on the vessel the heat may cause the seal to weaken from thermal expansion. I've never been burned by the pressure increase, but I have had a leak around the stopper in a rather hot (50 C?) Erlenmeyer that I was shaking and inverting. After that experience I now either pipette-mix or use a magnetic stirrer for extractions with hot/solvent solution. Seems just as effective as shaking and much easier and safer for hot vessels. I've used these techniques for performing hot pulls at up to 85 C.

^^^ risk for leakers, good point!

I use 35-40 °C heptane, usually just for the last two pulls or just for the last pull.