Rotovap solvent recovery time?

Yea, running as hot as I have been I’m thinking -22" is about as low as I want to go. I know there is a point of diminishing returns once you start cranking the heat and vac higher, and some say it counterintuitively actually slows you down. That’s pretty damn good for a 3L.

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Are you running the Chinese 20L version of the RE-501? I’m looking at picking one up in the near future. How is the price on the secondary condenser? All the secondary condensers I’ve found for a 20L roto are the AI upgrade (not sure if it would fit a Chinese model). Though admittedly I haven’t put all that much time into searching and it seems AI is on point with their marketing for their upgrade.

Nope I’ve got the same 5L from USA Lab. I meant I have a cold trap attached to the vacuum line, nothing fancy, just a $100 dewar. The rate I gave you is kinda confusing, i have it attached to a keg, with a scale under it. I have a 2L reciever flask under the cold trap. When the scale hits 40L/KG the 2L reciever flask is usually full

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Ahh, my damn lack of reading comprehension got me again. I saw 20L and for some reason assumed a 20L roto. Did you have to use some kind of special tri-clamp/keg seal for the keg? Years ago I had a seal that was flat on one side but ridged on the other for the tri-clamp fitting that I was using on my still (keg as a boiler) but that seal is long gone and I can’t seem to find one like it now. I know the double ridged standard gasket on the flat top keg neck was giving me leaking issues on my moonshine still, so I was worried about having that issue under vacuum.

$270 for all u need
$168

$90

$13
https://www.amazon.com/Dernord-Teflon-Tri-Clamp-Gasket-Ring/dp/B07CHB8X5M/ref=mp_s_a_1_4?keywords=4+inch+ptfe+gasket&qid=1557531707&s=gateway&sr=8-4

I live like 20 minutes away from them, so I’ve been picking up kegs from them, I dont think shipping is too much. I’ve gotten two with the 1.5" port at the bottom. Havent used the 1.5" ports yet, so I would just get the regular ones. I’m kinda short/small, so my arm fits in there, 4" was perfect for me. I can get all the way to the bottom, but if u prefilter well, u never have to stick ur arm in. The topping straws only leave 100ml left in the keg, its sweet. Just flush that out to clean it. Using two portions of 500ml was enough to flush the liquid and make it look clear at the bottom(the 100ml left) u can flip the keg upside down too, and it drains really well if u have a funnel to catch it
I’ll probably pick up 4 more soon. And just swap caps for topping straws. But I recommend getting two, so u can use one keg for ur extract, and the other for ur clean alcohol.

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Dude, this is a fucking SWEET find! Thanks for the links, I’ll have to put an order in very soon. :grin:

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Your 20mins from usalabs? I’m about 40. Shoot me a dm.

Sorry i meant 20 minutes from tcw in Santa rosa

I use an auxiliary condenser and get 2gph out of my 5 liter. It’s maxed out adding more kw does nothing.

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i hit 2litres / hr on the re501 @ 70C 25hg constant maybe around -20 in my saline d/i bath for my water pump. i go all the way up on my rpm , was going 68 for a bit but wasnt getting great results

if you’re at 20+ Hg at 70C that sounds odd that you’re only getting 2L

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I’m curious what rates people are getting from the 20L rotos with dual condensers like this one I found. It’s spec’d at 12L/h, but that’s the same rate as what is advertised with the single condenser rotos I’ve seen.
https://www.ebay.com/itm/Toolots-WTRE-20dual-5-3-Gallon-20L-Rotary-Evaporator-with-Dual-Condensers/223509974551?hash=item340a3b8e17:g:VUAAAOSw4Jlc1HPR

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I have an AI 20L. Nothing special it’s only single condenser and receiving flask with a Welch 2502 diaphragm pump.

Right now I’ve been pulling ~10L/hr with pretty basic settings. No idea what it would do if I pushed it hard but I don’t wanna risk breaking glass.

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running a china 20L single condenser with small aux condersor,and as hot as I could comfortably go, and also as cool as I could get
I got to 30 gallons in an 8 hour shift… for whatever that’s worth…

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I just realized I’m at 5,000 feet above sea level. So I guess I’m actually pulling somewhere along the lines of -27”hg?

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No more glass for me, I’m getting 20l an hour @ 38c vac wide open.

Here’s the condenser.

https://future4200.com/t/tri-clamp-condenser/18750![image|666x500](upload://2nUkeLd4dRImcTUR6Eo6vUq6Sce.jpeg)

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I’m noticing vapor go straight up past the top coil into my vacuum pump at 23”hg 50C water bath

Chiller is set at 0C, has anyone had a problem like this where the chiller seems to be okay temperature wise but the coil is not condensing?

How fast does the chiller push the liquid around?

The only times I’ve seen that are when I’ve had a vacuum leak or not using a cold trap, is the coil not condensing at all?