Using a Mechanical Cold Trap with Vacuum Ovens

Hi All,

So, I’ve always used dry-ice cold traps between my vacuum ovens and vacuum pumps, but I’ve never had the opportunity to use mechanical cold traps in this situation.

Does anyone have some anecdotal experience with this?

I’m a little concerned about condensing too many flammable volatiles at -105C (not quite condensing oxygen but pretty damn close). The pumps are scroll pumps if that makes a difference.

Just looking to see what people have to say about their experiences w this type of setup.

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I use this same set up but only -40 deg C for vacuum ovens. I only use the -80 or lower pumps on short path setups. My pump is a edwards 6ic dry scroll explosion proof ran through an across international -40 cold vapor trap with a kf25 inlet/outlet. I found that the first gen across internationals are very close to the current shscientific (korea) type vapor traps, and that the current generation are not as hardy. I had two AIs die on me before warranty. The night the trap died my scroll pump took a sip of what was inside and pretty much forced a rebuild within a month of that event. No fire though so the systems worked as they should. After the rebuild the pump is extremely loud and annoying while it pulls down.

I think they’re great. Definitely extends the time between rebuilds. Used for shatter, ethanol and butane crude decarb, drying powders and drying glassware.

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They’re great, let me sell you one at 10% off!

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I already have three, but I respect the hustle!

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Oh, then I’d imagine trial and error is going to fair better than the forum

Agreed, I’m a big proponent of offgassing thoroughly in the room so maybe I’ll just end up with some interesting terps.

Was thinking one day it might be a good idea to backfill with N2 so they don’t oxidize

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Back fill but also n2 sweep is expert level status. N2 sweep will speed things up.

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They also work great for other things…

Scored this haake-110 for $800. It only got down to -30 until I replaced the condenser fan. Now it freezes my hexane without hesitation. I also get no detectable vapors from my dry scroll pump.

It was kind of to good of a deal to pass up otherwise I would have picked a different temp, but I use with with my vacuum oven and rotary dryer.

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Whats the green thing

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A tumbler vacuum dryer it looks like.

https://www.cphi-online.com/rotacone-vacuum-dryer-prod905043.html

Edit: kinda figured it was something like that because he mentioned a rotary dryer

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I’ve got one of these still in the crate waiting to be played with… soon https://shopbvv.com/collections/cold-traps/products/ct40-40-f-300ml-x-3-cold-trap

Can you distill terps in the oven as efficiently as an spd?

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That’s correct. It’s a double cone rotary dryer. It’ jacketed and rated for full vac. It slowly rotates and agitates your powder while removing residual solvents. I can dry 30-40kg of isolate at a time.

It’s a classic made in 1984. Carbon steel outer jackets and all stainless contact surfaces.
The unit was cheap due to having a leaking jacket, about 30 hours of work my time and labor and it was working as it should. total cost, under $4000.

First video is me pressue testing and making sure its sealed while rotating.

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I like when I guessed right!

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How does this guy work for you?

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Works great, I wouldnt use it for distillation due to the way it seals but for anything that doesnt require a perfect seal or super deep vacuum its great. Especiialy for less than 1k

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Yeah man talk about a steal. Looks really promising for large scale isolate drying.

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No. Your terps will bounce out of that. It will take then apart and you’ll smell then in that room.