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Anyone know where I can get a LARGE soxhlet extractor?


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What are you extracting and what's your solvent?

There is nothing magical about the soxhlet apparatus.  It's really cool to watch, but realistically, it's just maceration with a solvent and a fun toilet bowl flush.  There is no difference between manually doing this with large glass beakers and filter paper, other than the manual labor.  Heck, you could fig up a pump to eliminate the need to make vapor and reflux,  and automate most of the process.

Alternatives might be a Coffee Percolator, Ultrasonic bath, water bath, rotovap, vacuum distillation, etc etc etc.

Seeing the 2-4 weeks, it sounds like we're talking about very hard, thick botanicals (barks, roots, etc) - I'd say ultrasonic bath is going to be far more interesting to speed things up than soxhlet.  I'm not a huge fan of high temperature extractions like soxhlet, you are cooking your extract for a long duration.  Anything thermally sensitive doesn't stand a chance.  Using a warm ultrasonic bath gets you speed, efficiency, volume, with far less thermal degradation.

Grinding to powder than vacuum filtration to remove particulate also an option to speed things up - not possible in a soxhlet, you'd just clog it all up.


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2 hours ago, Silk City Distillers said:

What are you extracting and what's your solvent?

GNS, a mix of various things - from fresh citrus and herbs to dried stuff.

My goal is to speed up the maceration process. I would ideally like to get it done in a few hours.   I figured a soxhlet would do that best. You're right that a pump would do the same, but would it do it at the same speed cold? I don't want to heat up the fresh botanicals. The dried ones I don't care about as much. 

I probably should have titled the thread "How do I do extractions faster". 

I'll check out the ultrasonic baths. If you have a link to one you think that would work that would be appreciated. 

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i can throw a jar in the ultrasonic, give me a rough recipe to try out.

A good use case for soxhlet is determining the oil content of a botanical prior to large scale gin distillation to establish high batch to batch consistency, especially if you have multiple botanical suppliers or if there are seasonal impacts.

Test a small sample, verify the oil %, if it’s in range, run, otherwise adjust botanical weights to account for the oil content differences.

You generally don’t see soxhlet being used for pilot development, and seeing that same approach being scaled upwards.

I’ve seen some large glass soxhlet units, but they cost a fortune, and are probably incredibly fragile.  Even the one I’m thinking of was only a 2 liter flask on the bottom.  


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I just listened to an episode of Distillers Talk with Alan Bishop where he had Jeff from Still Dragon on and they actually talked about this exact thing. Jeff states he has made them before and can make them with off the shelf parts, so I'd give him a call.  Jeff Rasmussen 954-638-6626

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On 2/22/2024 at 10:11 AM, Foreshot said:

Thanks - Try mint/basil/rosemary/dill in equal amounts if you can. How do you measure oil content? That would be key for me for consistency. This is a new area for me. 

Assuming fresh, not dry, yeah?  I'll have to make a trip to the grocery, but I can fire it up later.

Let me see if I can find a good video on the soxhlet measurement.  You'll be using a different solvent than ethanol (usually hexane), and the measurement is based on before and after weights.

Steps would be along the lines of:

Dry botanicals, weigh, load the soxhlet, run the soxhlet, remove the botanicals, dry again to remove the solvent, and weigh again.  Compare the weights.  Rotovap or vacuum distill off the hexane to separate the solvent from the extract, weigh that product, which should correspond with the botanicals weight difference.   You can't really weigh the solvent, because you are going to lose some during the soxhlet process, and in the wet botanicals.

Alternatively, you can use the "Clevenger Method"  - https://faculty.uobasrah.edu.iq/uploads/teaching/1652045269.pdf - this is safer, it's just using steam distillation and takes advantage of the oils separating from water.  Downside though, this needs to be babysat.  

Oldie but goodie from 1937 - https://www.stilldragon.org/uploads/FileUpload/13/97075c1c9998a51c7bcf39564a78e0.pdf

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