Solvent Recovery Still Recommendations?

So I need to get a better setup than a rotovap for solvent purification/fractionation. Need a still that will let me separate methanol, hexane/heptane, acetone and ethanol. Not sure what to get. Anyone have recommendations?

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scale? budget?

if you need less than 5 gal, you should go with a glass reflux still from a chem glass supplier. I’m sure @Sidco_Cat could point you at one.

if you’re playing with 100’s of gallons, go with an off theshelf beverage unit with a long bubble column with a defleg on it.

In between? I’m using a 26gal conical fermenter with hot water running through the jacket as my recovery still at the moment. I’ve got a 2"x 8’ reflux column I can put on there if I wanted to use it to refine my recovered ethanol (which I might start doing. thanks @Soxhlet).

That same still head will fit on any sanke beer keg (15 or 7.5 gal. smaller available). heat double boiler or bane-marie style.


Solvent to be recycled is best segragated by type. Waste cans should be labeled, solvents then can be distilled separately. large fractional distillations with lots of fractions tend to be cumbersome, and time consuming. Save yourself some effort and “keep it seporated” like that song “come out and play” by the offspring.

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Not an easy possibility with my situation. I have to split the methanol/acetone/hexane/heptane as that is used in the chromatography. Cost is no factor for me.

Is there a ready made fractional solvent recovery still anyone knows of?

I can build you a glass one made from process pipe. How many liters? The biggest oldershaw column I can get is 4" beaded pipe flange. You’ll want a reflux devider too. I can get nice magnetic ones.

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How about BR instrument, spinning band solvent recovery stills?

I could start a new topic, or ask in @TheGratefulPhil’s thread, but think this falls fairly close.

I just asked the manufacturer on my 100gal vac assist still what his guess was for recovery time for 100gal of 190proof ethanol under vac. He said “an hr or two”!!

I’m having a really hard time with that number, but don’t really know where to start to come up with a better guestimate.

100gal EtOH. vac at -26" Hg or so, to give a boil temp of 35C. Driving with 60C hot water in jacketed vessel. Running coolant through the condenser at -25C if I can manage it.

What other information do I need (condenser area?)?

even pointers to the correct maths would be helpful

Edit: seems like heat input is a required parameter. still haven’t found the maths. I’ve been advised to throw 150kBtu worth of water heater at the problem.

Edit: made a new thread and took a stab at the math. looks like the manufacturer might be on target.


I was looking into this for awhile in regards to separation of methanol/water. CBG Biotech Technologies has some recyclers that they claim can get the job done, at least for 2 solvents. They aren’t expensive either. I have no hands on experience. Ive since moved on to the more pushing bottleneck of large ethanol recovery. Thanks and good luck.

Ethanol Recovery
Budget: 100k (half down and half at delivery) Budget significantly increasing if financing is an option.
Solvent ratio: depending on extraction solvent between 5% and 8% (5%oil and 95%ethanol)
Volume per week: approximately 250gal/week
max temp: 60-70C Im not trying to preserve terps. this temp may change as I’m going off rotovap set point which I’m sure doesn’t laterally convert to continuous feed operation systems.
operating hours: 24hrs/day Monday-Friday.

Thanks everyone