Heptan question

[downwardsfromzero]

Well no need to make joke from me.I couldn't understood because it says 4 pulls weiting each pull three times to separate. Anyway big problem with the extraction heppend and I starting new threed for it.

Have you ever visited Britain? That could help you to understand. Maybe I should have expressed my frustration a little more gently. It's good to know that you are sincere.

There has been quite a lot of hand-holding going on, so we would once again urge you to understand the principles thoroughly. This is of course no mean feat in a non-native language, as I have pointed out before to other forum members.

Coincidentally, I have tried repeated 25mL pulls and at 55°C they evaporate down to about 23.5mL over the course of the 10 minute pull time. After gathering about 160mL total of naphtha pulls I was definitely at the "fall over" stage of proceedings. (Ventilation was good, I was not being overcome with fumes!)

I used an experimental dual-basing method on an acetic acid MHRB tea so it'll be interesting to see how that turns out. More on that elsewhere.

Meanwhile I'll go take a look to see what your problems were...

 

[the_Architect]

It shouldn't be that difficult to find this stuff:

Disolvente de pintura - Bricotex

Disolvente de pintura o diluyentes para todo tipo de pinturas, esmaltes, barnices, etc. Disolvente universal, disolventes de cloro-caucho, decapante, aguarrás, etc.

www.bricotex.pro

http://www.leroymerlin.es/fp/164649...litro?idCatPadre=8441&pathFamilaFicha=010605#

I would really appreciate any information on good solvents at affordable prices in the country of the black bull:thumb_up: .

I´m tired of scavenging small cans of zippo lighter fluid (found a cheaper one at a chinese bazar, did a evaporation test and works well, but the label doesn´t provide you any info).

Getting lab grade products it´s pricy (specially transportation).

Another option I was considering is amazon, you can get imported "VM&P naphtha", "Bestine" (heptane), or other first brand products from the paint-construction industry, that are known and confirmed to work for extraction and re-chrystallization, in other countries.

 

[antares]

Look at automotive paint suppliers for fast drying panel wipe. It is used to degrease panels before spray paining. It is usually excellent quality naptha. I buy the U-POL brand off ebay. Make sure you order the fast drying type.

 

[the_Architect]

Look at automotive paint suppliers for fast drying panel wipe. It is used to degrease panels before spray paining. It is usually excellent quality naptha. I buy the U-POL brand off ebay. Make sure you order the fast drying type.

Thank you for the intel, it seems quite affordable, about five eur per liter.
I guess this is hexane, and you can use it for re-chrystallization.

But can you use it for the pulls and freeze-precipitation?
Also, does it smell? I care about neighbors (perhaps I should pretend to be painting, like in BBad).

 

[antares]

I use it for everything. It smells a lot less than petrol or kerosine (paraffin). The smell disappears quickly with ventilation. Worst case scenario is that the neighbours will think you are painting or gluing something.

 

[bionecrosis]

Downwardsforzero,
U gave me very bad advice to pull with 23 ml NPS was it a joke or I didnt get the point?

 

[the_Architect]

antares: thank you very much for the info.

bionecrosis: you can do 23 ml NPS pulls, 30 ml can pull 1 gr of spice (theoretically), I´ve done it before, specially if you ran out of naphtha...
The problem is to take it away with the pippete-syringe, whether your container (jar, bottle, flask, etc) has a conic shape or not.
I do 30-50 ml pulls because there´s always a thin layer that stays in the container.

downwardsfromzero has given you good advice.

 

[downwardsfromzero]

Downwardsforzero,
U gave me very bad advice to pull with 23 ml NPS was it a joke or I didnt get the point?

I was reporting, rather than advising. The 5.23mL was (as you clearly noticed) something of a joke.

8x25mL pulls at 55°C to yield 160mL of recovered solvent for a 48h freeze precipitation at -27°C which gave 410mg of light sulfur-yellow crystals with a small smear of yellow-orange oil, was no joke. Pics in the "Post your yields" thread, soon to follow.

In all these weeks and months of you prevaricating I've recovered twice your yield using a somewhat unconventional spin-off technique and I haven't even processed all the bark soup yet.

This was three (5% acetic) acid PC cooks on 50g MHRB, settled in the fridge for a week to precipitate tannins, filtered free of the tannins, and bas-i-fied at nominal concentration using first lime then sodium carbonate.

Pulls were done with light naphtha (Waschbenzin) - stirred, not shaken (screw James Bond!) I may perform a final pull with heavier naphtha, or maybe octanol just for giggles. And there's clearly some goodies left in the Waschbenzin because that's a laaarge volume I've used.

Vessels used were straight-sided preserving jars. Pulls were retrieved using a glass syringe. I also used three teaspoons, a pressure cooker, some aluminium foil and some kitchen roll. And a damn good freezer.

That's more than anyone should need to know. Do, or don't do. The choice is yours.

 

[bionecrosis]

I don't mean for the 5.23 nl pull.I mean the 4x23 ml pull with heptane and didn't rend a lot... People say heptan pulslls should br larget anf for more time.

 

[downwardsfromzero]

As stated before, you want to do the pulls warm, and stir them vigorously for ten minutes apiece.

And that was eight of them for me - which, incidentally, went through the base soup effectively twice as I had separated a lower sludgy layer from an upper clear liquid layer. That makes for 16x10mins plus an extra 5mins for separating the pulls each time, essentially adding up to make 4 hours of work for the pulls alone. The cooks had already taken about 6 hours because of filtering cooling and settling (tannin solubility drops rapidly below 100°C, making a hard-to-filter mess for the impatient...) to which we add a further two days for additional settling before the clear liquid could be decanted off prior to basing.

Then we have the two days in the freezer and an hour or more for warming up and drying off once the crystals are obtained.

Back to the solvent volume, my rationale (and that of most chemists) is that lots of small pulls are better than one big one and thereby one pulls a greater overall proportion of the goods. This means the solvent is more saturated when it's time for the freeze precip.

These are principles that you need to take the time to learn and understand and I know that can be difficult in a non-native language. Patience, however, appears to be a translingual skill (correct me if I'm wrong here.)

 

[bionecrosis]

Is nafta with cas number 64742-95-6 range C8-C10 good for pull?

 

[downwardsfromzero]

That naphtha should pull very nicely but you might want to recrystallise with your heptane as the higher MW components will be quite slow to evaporate.

 

[bionecrosis]

That naphtha should pull very nicely but you might want to recrystallise with your heptane as the higher MW components will be quite slow to evaporate.

I understand this,but my STB didnt work fine pulling with heptane.i did 4 pulls each pull 3x10 min with hot solvent and basic solutuion and the result was oily brown liquid,I doubt I sucked something from the based solution and after 3 re still this substance rest and nothing was disolving in the heptane.Probably I will buy tghis nafta pull backsalt and after that pull with the finest heptan

 

[downwardsfromzero]

Ahem. As I said:
That naphtha should pull very nicely but you might want to recrystallise the resulting freeze precipitation product with your heptane as the higher MW components of the C8-C10 naphtha will be quite slow to evaporate.