Sciencemadness Discussion Board
Not logged in [Login - Register]
Go To Bottom

Printable Version  
Author: Subject: What is the advantage of short path distillation over normal?
FireLion3
Hazard to Others
***




Posts: 218
Registered: 11-1-2014
Member Is Offline

Mood: No Mood

[*] posted on 28-2-2017 at 21:25
What is the advantage of short path distillation over normal?


I've never heard of short path distillation until recently coming across youtube videos of people distilling cannabis oil. Upon further research it seems that cannabis enthusiast almost exclusively use these. I'm not in the Cannabis industry myself, but it seems that many of the components of cannabis oil are very easily able to be distilled in a normal vacuum distillation apparatus.

Reading the wikipedia page for Short Path Distillation, the only advantage I can glean from there is that it mentions Short Path is useful for temperature sensitive compounds, because a vacuum is usually used... I fail to see how this is any different from a normal vacuum distillation.

There is the obvious advantage in that a short path apparatus is smaller and more convenient to handle. Wikipedia states that it is useful for purifying small quantities of materials, however, I've seen many videos on youtube of people distilling relatively large amounts of cannabis oil with these.

Does anyone have any knowledge about these?
View user's profile View All Posts By User
j_sum1
Administrator
********




Posts: 4670
Registered: 4-10-2014
Location: Oz
Member Is Online

Mood: Metastable, and that's good enough.

[*] posted on 28-2-2017 at 22:15


https://www.sciencemadness.org/whisper/viewthread.php?tid=71...

and if my word is anything to go by, https://www.sciencemadness.org/whisper/viewthread.php?tid=71...

I think one of the attractions recently is availability and simplicity. If all you are doing is concentrating your hooch then something that is one-piece and is currently flooding eBay is obviously an attractive option.
View user's profile View All Posts By User
macckone
International Hazard
*****




Posts: 1383
Registered: 1-3-2013
Location: Over a mile high
Member Is Offline

Mood: Electrical

[*] posted on 28-2-2017 at 22:26


Short path works well for high boiling point temperature sensitive compounds that are distilled under vacuum. It reduces the length of time the compound is at an elevated temperature. There is also less surface area to retain the compound which makes it good for small quantities.
View user's profile View All Posts By User
FireLion3
Hazard to Others
***




Posts: 218
Registered: 11-1-2014
Member Is Offline

Mood: No Mood

[*] posted on 28-2-2017 at 22:30


Are they basically just for the sake of convenience/compactness at the cost of separation/fraction efficiency?

I can definitely see how using one would take a lot of the hassle out of setting up a vacuum distillation, but beyond that I am at a loss.
View user's profile View All Posts By User
Geocachmaster
Hazard to Others
***




Posts: 145
Registered: 5-3-2016
Location: Maine, USA
Member Is Offline

Mood: Corroded, just like my spatulas

[*] posted on 1-3-2017 at 05:04


I use short path distillation when:

The boiling point is pretty high (160+)
There is a small amount to distill and I want to minimize losses
I am feeling too lazy; it is very easy to set up

I don't use it when what I'm distilling is quite volatile, i.e. Acetone, methanol, diethyl ether and DCM (when I finally get some).
Edit: I also wouldn't use it for liquids with close boiling points, but then again you should be using fractional distillation if the boiling points are close. The surface area between the boiling flask and stillhead isn't much less than for simple distillation, so separation shouldn't be too much worse.

A short path condenser is very useful, and it's nice to have around if you can spare the money. It's not necisarry though, and I got by without one for a while.

[Edited on 3/1/2017 by Geocachmaster]
View user's profile View All Posts By User
Rhodanide
National Hazard
****




Posts: 334
Registered: 23-7-2015
Location: VHS Land
Member Is Offline

Mood: That retro aesthetic

[*] posted on 1-3-2017 at 05:47


Quote: Originally posted by FireLion3  
I've never heard of short path distillation until recently coming across youtube videos of people distilling cannabis oil. Upon further research it seems that cannabis enthusiast almost exclusively use these. I'm not in the Cannabis industry myself, but it seems that many of the components of cannabis oil are very easily able to be distilled in a normal vacuum distillation apparatus.

Reading the wikipedia page for Short Path Distillation, the only advantage I can glean from there is that it mentions Short Path is useful for temperature sensitive compounds, because a vacuum is usually used... I fail to see how this is any different from a normal vacuum distillation.

There is the obvious advantage in that a short path apparatus is smaller and more convenient to handle. Wikipedia states that it is useful for purifying small quantities of materials, however, I've seen many videos on youtube of people distilling relatively large amounts of cannabis oil with these.

Does anyone have any knowledge about these?

Ahhh, the chemistry of "Weed" :]
View user's profile View All Posts By User
FireLion3
Hazard to Others
***




Posts: 218
Registered: 11-1-2014
Member Is Offline

Mood: No Mood

[*] posted on 1-3-2017 at 17:55


Quote: Originally posted by Tetra  

Ahhh, the chemistry of "Weed" :]



It's interesting because out of the many lab stores I've been to around the country, the ones in medical states always seem to very vocally advertise their cannabis refining equipment, with whole sections of the store dedicated to glassware most commonly used by cannabis enthusiast. An interesting yet unanticipated effect of medical marijuana... significantly more business for lab stores. Prior to the last 5-10 years, I have never heard of anyone using laboratory equipment to refine their cannabis products, even in the early medical states.

[Edited on 2-3-2017 by FireLion3]
View user's profile View All Posts By User

  Go To Top