Register ICMag Forum Menu Features Search Today's Posts Mark Forums Read
You are viewing our:
in:
Forums > Talk About It! > Cannabis Concentrates > Rotovap questions

Thread Title Search
Post Reply
Rotovap questions Thread Tools Search this Thread
Old 10-13-2017, 06:32 AM #21
WaterFarmFan
Senior Member

WaterFarmFan's Avatar

Join Date: Mar 2008
Posts: 1,794
WaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to all
Quote:
Originally Posted by GNYC View Post
lol with such a large amount we've always just hooked a hose from the fractional to the injection port for the roto and put an extra long injection tube on first inside the ball. then turned on the vac on the fractional and pulled as much as we could via the hose and then rehooked everything back up and went about our jobs. we wouldn't get it all out of the roto and wouldn't worry about it unless we switched strains or parameters of something. then we would do exactly as you listed above.
I have a question about ethanol distillation, but not using a roto. Say that I have a 5 liters to distill using a 2l mantle, which I would do in 3-4 runs. When I start the process and pull vacuum, temps drop in the flask to the high 50s F and as the ethanol evaporates over an hour temps rise to the 90s. I am trying to keep terpenes, so high temps are bad. I found that once I get to ~90% evaporation temps can really shoot up fast (over 100F) if my mantle is too hot, but if I don't push temps than purge is too runny to start.

So my question is this: Is it advantageous to just leave the extract in my boiling flask (at 80-85% etoh evaporation) and then add another liter or so of solution to flask each time temps reach 90s until gone? Logic would be that I only have to push temps higher once and a larger volume of extract mass could reduce the explosive out gassing that splatters the walls of flask towards end.

I appreciate any insight.

WFF
WaterFarmFan is offline Quote



Click to shop for Extractors and Hardware
Old 10-13-2017, 12:25 PM #22
Gray Wolf
A Posse ad Esse. From Possibility to realization.


Gray Wolf's Avatar

Join Date: Apr 2009
Location: River City, USA
Posts: 9,548
Gray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant future
Before rotovape, we distilled off large quantities to the syrupy "bumping" stage and finished off in a vacuum oven using a shallow dish with a sheet of glass over the top to catch the bumps.

If you combine them all for the final finish, you should limit the heat cycling.
__________________
An age is called Dark not because the light fails to shine, but because people refuse to see it.

Believing is seeing and ignorance is bliss until it bites you in the ass!

Fervor is the weapon of the impotent. The harder the sell, the poorer the product.

Alas, my ignorance abounds; the more I've learned, the less I know that I know..........

Thou shalt seek and respect the opinions of operators, even unto the third helper, for theirs is a wisdom unknown to technicrats.

Wise men learn more from fools, than fools from wise men.

In my dotage I finally discovered that the secret to putting on pants both legs at a time is sitting down.
Gray Wolf is offline Quote


1 members found this post helpful.
Old 10-13-2017, 06:46 PM #23
WaterFarmFan
Senior Member

WaterFarmFan's Avatar

Join Date: Mar 2008
Posts: 1,794
WaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to all
Quote:
Originally Posted by Gray Wolf View Post
Before rotovape, we distilled off large quantities to the syrupy "bumping" stage and finished off in a vacuum oven using a shallow dish with a sheet of glass over the top to catch the bumps.

If you combine them all for the final finish, you should limit the heat cycling.
Thanks. Is "combine them all for the final finish" the same as never pouring out extract until very end of distillation? I really don't want to disassemble distillation rig each time to pour out until finished and just use the second neck with 24/40 funnel to add additional etoh solution until gone.
WaterFarmFan is offline Quote


Old 10-14-2017, 11:44 AM #24
Gray Wolf
A Posse ad Esse. From Possibility to realization.


Gray Wolf's Avatar

Join Date: Apr 2009
Location: River City, USA
Posts: 9,548
Gray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant future
Quote:
Originally Posted by WaterFarmFan View Post
Thanks. Is "combine them all for the final finish" the same as never pouring out extract until very end of distillation? I really don't want to disassemble distillation rig each time to pour out until finished and just use the second neck with 24/40 funnel to add additional etoh solution until gone.
I was suggesting pouring off the syrup each time but combining them wouldn't be a disaster.

Some decarboxylation occurs with boiling, but shouldn't be a lot if you're down to -28" Hg, which ostensibly is around 19C/66F.
Gray Wolf is offline Quote


1 members found this post helpful.
Old 10-15-2017, 08:11 PM #25
GNYC
Newbie

Join Date: Oct 2017
Location: SoCal
Posts: 15
GNYC will become famous soon enough
I've only ever used a rotovap so I would definitely take GW's advice his science is solid behind the explanation.

Quote:
Originally Posted by Gray Wolf View Post
Before rotovape, we distilled off large quantities to the syrupy "bumping" stage and finished off in a vacuum oven using a shallow dish with a sheet of glass over the top to catch the bumps.

If you combine them all for the final finish, you should limit the heat cycling.
by syrupy bumping stage you mean when it starts to congeal into the solid mass you'd add to your mantle? Everyone uses different terminology when discussing stages/states of the fluid in the process lol. I'm just trying to make sure I understand that you are purging your ethanol via vac oven? If so the glass plate over top is to reclaim ethanol, or is it to help retain heat?
GNYC is offline Quote


Old 10-16-2017, 11:56 AM #26
Gray Wolf
A Posse ad Esse. From Possibility to realization.


Gray Wolf's Avatar

Join Date: Apr 2009
Location: River City, USA
Posts: 9,548
Gray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant futureGray Wolf has a brilliant future
Quote:
Originally Posted by GNYC View Post
I've only ever used a rotovap so I would definitely take GW's advice his science is solid behind the explanation.



by syrupy bumping stage you mean when it starts to congeal into the solid mass you'd add to your mantle? Everyone uses different terminology when discussing stages/states of the fluid in the process lol. I'm just trying to make sure I understand that you are purging your ethanol via vac oven? If so the glass plate over top is to reclaim ethanol, or is it to help retain heat?
The glass plate is to catch the spatter from the explosive burst (bumping). It is easy to remove from the sheet of glass with a razor blade, but not so easy from all over the inside of the oven.
Gray Wolf is offline Quote


Old 10-16-2017, 06:11 PM #27
Thomas@LRL
Member

Join Date: Oct 2015
Posts: 141
Thomas@LRL has a spectacular aura aboutThomas@LRL has a spectacular aura aboutThomas@LRL has a spectacular aura about
Quote:
Originally Posted by Gray Wolf View Post
Before rotovape, we distilled off large quantities to the syrupy "bumping" stage and finished off in a vacuum oven using a shallow dish with a sheet of glass over the top to catch the bumps.

If you combine them all for the final finish, you should limit the heat cycling.
This is the first time I've seen someone mention covering the dish in the vacuum oven, would using parchment paper work just as well or is it not heavy enough? I have a few Pyrex baking dish that I've been itching to give a shot, we control the boiling enough to prevent it from boiling over, but small splatters are inevitable and a small plate of glass or parchment would save a ton of cleaning.
Thomas@LRL is offline Quote


Old 10-18-2017, 01:37 AM #28
WaterFarmFan
Senior Member

WaterFarmFan's Avatar

Join Date: Mar 2008
Posts: 1,794
WaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to allWaterFarmFan is a name known to all
Quote:
Originally Posted by GNYC View Post
by syrupy bumping stage you mean when it starts to congeal into the solid mass you'd add to your mantle? Everyone uses different terminology when discussing stages/states of the fluid in the process lol. I'm just trying to make sure I understand that you are purging your ethanol via vac oven? If so the glass plate over top is to reclaim ethanol, or is it to help retain heat?
I understand syrupy bumping stage to be somewhere around 90% removal of etoh, and it's where the extract solution goes from a thin liquid to runny syrup, and it can happen quite fast. You know you are there when extract starts occasional explosive splattering that coats the boiling flask in a thin film. Temps can shoot up 20F inside the flask within a few minutes. I try to time the very beginning of this stage (in order to not ramp temps to preserve terpenes) and remove the flask from mantle to pour out extract for purge in a vacuum oven.
WaterFarmFan is offline Quote


Old 10-18-2017, 07:27 PM #29
GNYC
Newbie

Join Date: Oct 2017
Location: SoCal
Posts: 15
GNYC will become famous soon enough
So i've only ever made oil with my crude using a Closed Loop BHO system winterization filtration and then solvent extraction using the 20 L rotovap (pic below). That being said, i've always left it slightly viscous in order to get it to transfer smoothly to the fractional distillation mantle. I would just purge the last remaining small percentage of ethanol there w/ the first fraction of terps (since they are pretty much ruined from the bho/fractional distillation process). I guess I could do what GW suggested and put the syrup in a pyrex in a vac oven and put a glass plate on top and purge completely, but I don't know what the benefits would be comparably in methods to doing this. I don't think i've every brought it down in the roto to the point where it bumps only time I've ever brought it to such a stage would be in the fractional mantle. I am currently looking into CO2 extraction systems so i can do Fractional Separation rather than straight to fractional distillation so i can as you would like to preserve the terps. then go back and refine after combining the different fractions back together w/o terps and put them through fractional distillation and upon completion of that process reintroduce the natural terpene profile back to the end product. Unless I have the whole process confused of how it works? I've only been doing this for a year and ever since finding this treasure trove of a forum I feel so far behind compared to people like GW, Sky, Pangea, and others so I'm always up to hear how anyone else is attaining their desired end result.
Attached Thumbnails
Click image for larger version

Name:	22563669_10101209216263118_1210767761_o.jpg
Views:	23
Size:	55.1 KB
ID:	432555
GNYC is offline Quote


1 members found this post helpful.
Old 07-30-2018, 06:35 PM #30
SkyHighLer
Got me a stone bad Mana

SkyHighLer's Avatar

Join Date: Jul 2013
Location: Southern California
Posts: 2,384
SkyHighLer is a splendid one to beholdSkyHighLer is a splendid one to beholdSkyHighLer is a splendid one to beholdSkyHighLer is a splendid one to beholdSkyHighLer is a splendid one to beholdSkyHighLer is a splendid one to beholdSkyHighLer is a splendid one to beholdSkyHighLer is a splendid one to beholdSkyHighLer is a splendid one to beholdSkyHighLer is a splendid one to beholdSkyHighLer is a splendid one to behold
Quote:
Originally Posted by whatthe215 View Post
Both. My recommendation for flasks with a large enough opening (China 20L and 50L flasks) is this:

- Buy arm gloves, the kind for inseminating cows and some rubber bands to hold it at shoulder. Have silicone spatulas.

a) Finish rotovaping @ ~60c, kill vac, stop rotation, insert stopping key (so it doesn't rotate when you unscrew,) then let sit for 10-15min so oil can collect from walls and get to temperature 60c.

b) Remove evap flask and pour out as much oil as you can. Let sit upside down for 5-10min dripping into collection container. Use heat gun carefully if desired.

c) Turn evap flask so that you can reach in with arm glove and spatula and scrape out as much as you can. After the first time you'll probably dial in the method. I scrape the top first so I can see inside. Scrape upwards and then pull the oil covered spatula out and deposit into collection container.

** You'll dial in time to wait before starting spatula scraping depending on oil consistency/type. Too early = too hot for your arm and oil will fall right off spatula, too late = very difficult to scrape, more left behind. There's a perfect 5 or 10 min window. **

d) Use minimum amount of ethanol/solvent required to dissolve left over oil in flask. Save it for rainy day, put it in your ultrasonic solvent bath, whatever. Rotovap once you've got enough and need the solvent back. Squirt bottles help. Using arm gloved hand to swish solvent around and rub sides helps tremendously.

Done properly and with fresh arm gloves, I can't imagine a cGMP inspector or whatever having much of an issue with this method, although it may seem a bit ghetto.


Alternatively, throw away the rotovap and get an industrial solvent recycling machine.
Quote:
Originally Posted by SkyHighLer View Post
"Alternatively, throw away the rotovap and get an industrial solvent recycling machine."


There is no reason to use a rotovac to rip solvent when the oil is going to be fractionated.

Rotovacs are extremely dangerous, and extremely expensive, and are invaluable in the lab, where they belong, these are not generally meant for production situations when viable alternatives exist.

Rather than step all the way up to industrial solvent recovery systems, there is a line of common commercial solvent recovery systems that should do nicely, they are referred to as solvent recyclers.

The smallest, 3-5 gallon units are used for such things as automobile paint shop in-house solvent recovery, machine shops, etc.

Much larger sizes, and various options, including vacuum/feed/removal are available.

The smaller units use nylon or Teflon bags, remove the bag, cut a corner, and let it drain, squeegee all but the very the last out.

These units have advanced controls to allow the use of solvents with various boiling points. (The new controllers with both power and temperature control would be better yet, recently I've proven to myself that floating the temperature at the boiling point, and adjusting the boiling level by regulating the power available to the heater is far smoother than trying to control the boiling with PID temperature control alone. This goes for your Buchi and Heidolph rotovapes too, lol.)


BECCA SS17.5 (17.5 Gal) Solvent Distillation Recycler - Features

https://www.youtube.com/watch?v=m8jgVCHO-Gw


BECCA HC (6 Gal) & SC (3 Gal) Solvent Distillation Recycler - Features

https://www.youtube.com/watch?v=_NDX8GghGrk


Sidewinder Model M2 Presentation

https://youtu.be/q-bM74dCZ4k?t=33s

I've been try to stoke up interest in commercial/industrial solvent recovery machines for a couple of years here at ICMAG Concentrate Forums...

https://labsociety.com/lab-equipment/solvent-recovery/


Automated Solvent Recovery System (ASRS)
from: $57,190.00

– Lab Society

Solvent Recycle

Recover more solvents than you ever thought possible.

Our top-of-the-line Automated Solvent Recovery System (ASRS) was designed to meet the needs of even the most demanding of industrial laboratories. Instead of letting valuable solvents go to waste, you can now easily recover them on a larger scale than ever before.

High volume lab? Not to worry.

Early real-world tests show that these units perform well beyond specifications, letting you recover more of your solvent per hour than by any other method on the market.

Finally, a plug-and-play solution for top-of-the-line labs.

Thanks to a variety of sensors and automations at the heart of these machines, all of our (ASRS) units are able to run safely with minimal operator intervention. For busy lab owners, this product is a game changer. In most cases, it’s a simple matter of plug and play.

Features:

set it and forget it – Just put the used solvent in, and watch the clean solvent come out.
multiple, large-scale sizes – (32, 50, 75, 110 Gallon options available)
process insane amounts of solvent per hour – (5.5, 9.1, 16.6, 18.2 gallons per hour, respectively)
vacuum-assisted – Allows for a reduced atmosphere, which lowers boiling points and increases evaporation speed!
remotely accessible via ethernet or cellular data
electric heating (with thermal oil)
collection container sensors prevent overflow and spills
includes free lifetime service and support (including remote access)
480 volts – make sure you have the proper power available
automatic hydraulic tilt lift available upgrade
Shop Solvent Extraction Products Online

Vacuum assisted.

These powerful machines use a vacuum in the boiling chamber to lower the temperature needed to boil high-boiling-point solvents. Each premium unit uses a Liquid Ring Vacuum System for maximum efficiency.

Remotely accessible via ethernet or cellular data.

The system PLC is accessible remotely through an Ethernet or cellular data connection. Settings can be viewed and changed as if the touch screen was being used.

Electric heating (with thermal oil).

Uses a thermal oil jacket electric heater to quickly and evenly heat the boiling vessel.

Collection container sensors prevent overflow and spills.

The last thing you want is a massive solvent leak in your laboratory, or worse, volatile chemicals and vapors everywhere. That’s why we’ve integrated intelligent sensors to prevent spills and to stop these machines from overflowing.

Not only that, our automated premium solvent recovery units are:

Recycling Alcohol, Ethanol

Safe – Class 1, Div 1, Group D, explosion-proof, METLAB Certified
Strong – High quality 304 stainless steel construction
Simple – Automated operations, tilted base for easy residual product removal and access
Smart – Highly automated, with touch-screen PLC and remote cellular access
Note: The ASRS requires the use of a 480V standalone chiller.



Compare to the solvent recyclers that can be found at the Sidewinder and Becca sites,

https://solvent-recycler.com

https://www.beccainc.com/solvent-dis...ing-equipment/


I mentioned in the quote there are better controllers with both power and temperature controls now available that would provide smoother distillation. Shouldn't take an electrical genius to figure out how to swap out the controller, here's a post explaining the new controllers,

https://www.icmag.com/ic/showpost.ph...4&postcount=22

The Auber controller referred to (either the DSPR220, or DSPR440 with relay output) drives a solid state relay, or two, or three, it can drive up to 5 or 6. The solid state relays are available in 3-Phase configuration, here's an 80A per Phase device from Auberins,

https://www.auberins.com/index.php?m...roducts_id=105
Attached Thumbnails
Click image for larger version

Name:	solvent-recovery-system-asrs.jpg
Views:	7
Size:	40.7 KB
ID:	464648 Click image for larger version

Name:	ASRS-automated-solvent-recovery-system.jpg
Views:	7
Size:	45.0 KB
ID:	464649
__________________
Link won't open?
1. Click on the link.
2. Click in the address bar, and use backspace to remove the s in https.
3. Click on the 'reload this page' icon, or hit the return key.

Best to Worst Canned Butane List
https://www.icmag.com/ic/showpost.ph...6&postcount=28

Cannabis Alchemy by D. Gold
https://calgarycmmc.com/E-books/E%20B...0D.%20Gold.pdf

Hash oil techniques and solvents for non BHO hash oil?
https://www.icmag.com/ic/showthread.php?t=338633

Solvents listed as to polarity
https://www.icmag.com/ic/showpost.ph...&postcount=162

The Truth Machine by James L. Halperin (free read provided by the author)
https://coins.ha.com/information/ttm.s

Last edited by SkyHighLer; 07-30-2018 at 11:41 PM..
SkyHighLer is offline Quote


1 members found this post helpful.

Post Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT +2. The time now is 11:05 PM.




This site is for educational and entertainment purposes only.
You must be of legal age to view ICmag and participate here.
All postings are the responsibility of their authors.
Powered by: vBulletin Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.