Cloudy heptane plus heptane loss while lle

So, I’ve been out of the loop for some time. I now went back to degum and clean up some old red material.

Started with heating up 2200g oil to 90c. Used 2.5g degum powder stirred for 10 min. Then put 220g t41 in and mixed for 20 min more.

Poured 2.5 gal etho in and filtered through a 2-3 micron paper. Rotovaped out the etho.

Didn’t know how much heptane I had so I measured it in a 5l beaker. It was 3l, but it looked cloudy. Since I needed to do a water wash went ahead and mixed in the heptane with the oil in the roto. Had a meeting, so I let it mix with no heat or vac for an hour. Then poured into my 3 gal sep funnel. Poured a gal of brine in and noticed that the heptane/oil layer only was 4l from having been 5. There was no emulsion layer to speak of. Water came out red.

Washed another 1.5 gal brine and into into the roto.

It looks dirty as fuck. It was clean when just with the etho. I’m a bit pissed off at myself for doing it, but I’ve used this heptane before without it being cloudy. It’s literally been in its container for days without use until now. Has anyone encountered this before?

are you dehydrating it over magnesium sulfate before rotovaping it?

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No, I don’t have that. I have magnesol xl. Would that work?

No. You need a drying agent.

I would think the salty water would dry it no?

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Salt water prevents the dissolution of water into the heptane but it’s not exact, some water is going to dissolve. And if you used any distilled water before salt water, the salt water will help to pull it out but not entirely.

I’m gonna try filtering through bentonite to see if that removes the cloudiness if I can’t find magnesium sulfate.

@CannaChemistry

Mol sieve should work then?

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Yes 3a should work

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Just order some drying salts off amazon, they’re cheap.

I would if I had time. I’m trying to relocate next week and have a couple of last liters I wanted to clean up before. This could be a blessing in disguise. I got some 3a for $80. Way more than I need, but I think I’m gonna need them for the new endeavor anyway, so I’m gonna see how well they work

Well, pull me behind a wagon and call me the village idiot, but after rotoing the oil looks clean af. Now the only question is how I ended up with 1.7 liters heptane from 3 liters.

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Do you have a cold trap on your Rotovap? If not you are breathing it.

I’ve got a five gal bucket full of 4a sieves if you want something to dry your heptane lmk I can weigh out a few pounds for ya

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This seems like kind of the right thread to ask, does anyone have good values for solubility of MeOH in Heptane and vice versa?

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Does heptane need to be in gas form when it passes through the sieve also like tane?

I would think the reason to run it through as a gas would be that you’d only need to strip any water that codistills with the solvent. Adding the liquid directly to it should work still but more water means more adsorbent needed

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When this was done I was in a very well ventilated area and I never smelled the heptane. I also always use a full mask when dealing with alkanes. But there was a small extra cold trap (not submerged) between the pump and roto.

I have 10lbs of 3a mol sieve now. But I think I need more, cause I’m all of a sudden facing alot of issues due to changed solvent. I started at a new location and it’s been one headache after the other.