This is done in a large static column similar to a CLS material column.
That’s a good way to do it. Buddy of mine run a similar set up but he’s always had an issue with solvent loss and Hexane soaked biomass. I always had an idea about running a jacketed column that I could heat and pull vac on through a giant cold trap to recover the residual solvent in the biomass.
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Its an alright set up, loading and unloading sucks though. They hold 50kgs of biomass each so its a lot of wet mass to deal with, we actually pull vacuum on the column to get it a little dryer but its far from ideal. a jacketed column would surely help.
Have you thought about pushing water through the column into a separate holding tank and then letting it separate. Drain off the water and recover the Hexane. My thought would be that the water would act as a battering ram in the column pushing out the Hexane.
We have tried water as well but the water just soaks the biomass, it expands, then gets trapped in the column never making it to the bottom.
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ye me too jed 
I think its due to the breakdown of the plant material creating methane
When you say agitation do you mean overhead stirring or being turned in a rotovap?
I got some hexane extractied oil in my rotovap I’m trying to get to pass residual solvents so I’ve been rotovaping @140c and hoping a few hours will be enough to pull it off.
I’ve found the best method in the roto for purging with heavy alkanes is to turn the ball 1/4 rotation every 5 minutes or so. It’s basically like flipping a slab in the vac oven every 5 minutes only with better heat transfer.
Edit for funny anecdote: I had a lab tech that was very upset with me when I put a repeat cycle timer on one of our rotovaps to do this after making him tend 3 of them doing this for like a week lol. Took like 10 minutes to rig up. Builds character
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You have to run acetone at -80, it acts similar to etho
I use over head agitation with two 5” props at 1750 RPM.
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…2010? and the iphones come from china (or at least use to) so if anything they’re the ones poisoning us lol.
more like americans move big company to china so they dont have to give a shit about the
health of the people making the products.
so in a way its the otherway round we are poisoning them.
it was just more a means to show that hexane can be poisonous if inhaled.
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I figured i would come back to this and update a few more experiments I tried with this.
I tried doing a lighter packed column and pushing the water from the bottom (think LLE water will normally settle on the bottom) and pushing the hexane out the top, it worked to a point but the water still eventually expanded the biomass so much you couldnt force the water all the way to the top of the column.
It pushed some hexane out but not enough to be worth it.
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If you wanted the boiling point/vapor pressure benefits of hexane over butane, I would just go for heptane. Heptane is superior to hexane from a toxicity standpoint alone, but hexanes are also bad for the ozone layer.
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I agree Heptane to be a better choice over hexane for just about everything except the energy it takes to recover. its not a huge difference though.
If it was up to me i would have used heptane from the start and now im just looking for my time to scrap all the hexane and go to heptane.
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if it was a refinery you could just send it to flare!
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I bet if i just checked the progress with a lighter i could make it flare in place.
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lol @ Flare in Place (FIP) instead of CIP.
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clean it with fire
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My exact thoughts when i said that were FIP
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