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

Printable Version  
Author: Subject: How large amounts are separated?
Fyndium
International Hazard
*****




Posts: 1015
Registered: 12-7-2020
Location: Not in USA
Member Is Offline


[*] posted on 28-2-2021 at 11:03
How large amounts are separated?


How labs do bigger batches of separation and extraction? Bigger than 5L separatory funnels begin to get too heavy to handle, so I suppose they use stationary, stirred separatory funnels like in brewing?

Years ago, I did an improvised separatory funnel from transparent bucket and a valve. It did work great, and cost about 5€ with all the parts.
View user's profile View All Posts By User
itsallgoodjames
National Hazard
****




Posts: 265
Registered: 31-8-2020
Location: America Lite
Member Is Online

Mood: Doing novel energetics chem

[*] posted on 28-2-2021 at 17:59


If you're trying to separate large amounts of liquids, decant as much of the liquid as possible then use a sep funnel on the rest of it



Nuclear physics is neat. It's a shame it's so regulated...

Now that I think about it, that's probably a good thing. Still annoying though.
View user's profile View All Posts By User
Fyndium
International Hazard
*****




Posts: 1015
Registered: 12-7-2020
Location: Not in USA
Member Is Offline


[*] posted on 28-2-2021 at 18:28


During benzaldehyde synthesis I used glass tube and tubing to suction out the BzH settled to the bottom. So yeah, there are other methods too.
View user's profile View All Posts By User
zed
International Hazard
*****




Posts: 2208
Registered: 6-9-2008
Location: Great State of Jefferson, City of Portland
Member Is Offline

Mood: Semi-repentant Sith Lord

[*] posted on 28-2-2021 at 18:49


Use vacuum to siphon.
View user's profile View All Posts By User
draculic acid69
International Hazard
*****




Posts: 1197
Registered: 2-8-2018
Member Is Offline


[*] posted on 1-3-2021 at 04:12


I think once U go past the 5L point U go with buckets/tubs/the/drums with taps on them or go with the vacuum siphon method
View user's profile View All Posts By User
Praxichys
International Hazard
*****




Posts: 1053
Registered: 31-7-2013
Location: Detroit, Michigan, USA
Member Is Offline

Mood: Coprecipitated

[*] posted on 1-3-2021 at 08:14


Here is a 50L example. Coarse extraction is achieved using a bottom tap (in progress, see image). Once the boundary gets close to the drain, the flow is slowed to prevent a vortex which would cause waste.

When the level is as close to the layer as one can best manage, the valve is closed. Rapid stirring commences to dislodge adhering liquid from the reactor walls, followed by more settling time to let it fall to the bottom.

The bucket is meanwhile swapped for a pitcher-like transfer container eventually used to fill a 2L sep funnel. The tap is pulsed open and shut a few times until the amount drawn reaches about 3/4 the volume of the sep funnel. This purges remnants of the heavy layer from the reactor and purges the valve body with product. The sep funnel is used as normal for fine separation and any product is returned to the reactor for the next step.


50L_Sep.png - 598kB


Siphoning with a long glass tube is also an option. This method would be preferable if the next step could not tolerate any waste from the previous step, as there are invariably adhering droplets. In my case they are taken care of during the drying step and are of little consequence.
View user's profile Visit user's homepage View All Posts By User
njl
International Hazard
*****




Posts: 563
Registered: 26-11-2019
Location: under the sycamore tree
Member Is Offline

Mood: ambivalent

[*] posted on 1-3-2021 at 08:27


What solvents are you using here?



Reflux condenser?? I barely know her!
View user's profile View All Posts By User
Praxichys
International Hazard
*****




Posts: 1053
Registered: 31-7-2013
Location: Detroit, Michigan, USA
Member Is Offline

Mood: Coprecipitated

[*] posted on 1-3-2021 at 11:33


Just water. The bottom layer is mostly aqueous sodium sulfate with some sulfuric acid; the top is product. This is just a big acid-catalyzed esterification.
View user's profile Visit user's homepage View All Posts By User

  Go To Top