I was wonder if you had an Hexane ethanol mix. Say 70% ethanol 30% hexane. Hexane having a lower boiling point. If you were to distill 35% of the amount you have. Would it pull all the hexane out of the ethanol?
I’m just curious why you would want to mix Hexane with Ethanol? Anything with a lower boiling point with evaporate before the substance with a higher boiling point in my experience.
You can also add water and they’ll separate… I think. Works with methanol anyway.
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In the case that the ethanol already has it in it and one would want to purify the ethanol
interesting. Did you buy this to avoid the tax on 200 proof ETOH or was this from doing some post processing?
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Now that reflux still head your still builder thinks you need is beginning to look useful.
It’s not about distilling 30% by volume.
It’s about watching the temp at the still head, and the flow from the condenser.
Best way to know for sure is to try. But only if you’ve got a reflux still and a thermometer in your head.
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PSA: In the US you would need an ATF license to buy SDA formulas for this blend. If you have said license you can order a c6/EtOH blend…but acquiring any other way is risky biz.
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So basically staying around 160f
Your better off throwing the mixture in Sep funnel and adding distilled water. The etoh will create an azetrope with the water and the two will quickly separate due to polarity differential. Once you remove all the etoh/water from the hexane, you can throw it into roto under deep vac at low temps to purify the etoh from the water.
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How much water would I have to add? Wouldn’t that take longer than just distilling the hex out in the first place? Seems like you are doing two things instead of one imho
You can definitely separate hex and etoh by rotovap, the question is how pure? Imho if I was trying to purify my etoh of all hexane, I would do it in a way that guarantees no nasty ass hexane in my etoh. Anitherwards full separation. Simple distillation will result in hexy etoh and that’s not acceptable.
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It sounds like it would be a hell of a lot easier to cleanly distill the ethanol from the water (to 190 proof) than trying to distill the hexane from the ethanol. Hexane also forms an azeotrope with etoh if I’m not mistaken (I could be totally wrong there). Water would break that azeotrope, as it breaks the methanol/pentane azeotrope in a LLE.
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What if it was like 5% hexane. Would it boil off first? And not have to add water to separate? Or does the ethanol and hexane form a bond? Like once the hexane is in it you can’t simply distill the % of present hexane and that would remove it? Because of the hexane having a lower boiling point?
Forgive me if I’m not as knowledgeable in this as I should be and thank you for the knowledge:)
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From my experience (pretty sure it’s universal), the lower the concentration of the compound with the lower boiling point, the higher your temp has to get to boil it off, which subsequently carries the compound with the higher bp with it. You would want to do fractional distillation if you wanted to cleanly distill the hexane from the ethanol. If you try to do so with simple distillation, you’re going to have to redistill it several times. And even then, you probably won’t get as clean a separation as with a fractional column. If there is an azeotrope between etoh and hexane, then you’re wasting your time trying to separate with distillation and need to use water anyway.
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If it’s 5% hex, all the more reason to add water.
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What ratio of water to alcohol?
If you know for sure that it’s 5% hexane, I would load a known amount into a sep funnel (let’s say 1 liter for example), then flush with water (recording how much water you’re adding) until you end up with 5% of the original volume left over on the top layer. Once you add the water, you’ll see two distinct layers form. So if you load one liter into the funnel, you should flush with water until you have 50ml left over as the top layer in the sep funnel. It’s probably going to take some time to mess with it, especially since most sep funnels aren’t graduated. But if you carefully record what you’re doing, you’ll pretty easily figure out exactly what ratio of water to etoh/hexane mix to add in order to achieve full separation without over-diluting the ethanol unnecessarily, and then the process becomes pretty fast.
Start low and work your way up with the water addition. The less you water you have to use, the easier it’s going to be to distill the etoh off the water.
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