Is it OK to reflux in a coil condenser?

aaa · Mon Jun 06, 2005 8:51 am

If so, are there any situations where a normal condenser is superior to a coil condenser?

The_Dude · Mon Jun 06, 2005 8:53 am

1. No

2. Refluxing

bio · Working Bee

mk-1 · Mon Jun 06, 2005 12:31 pm

I love my coil condenser, and i use it for all my refluxes. not even thinking about moving to a straight one.

aaa · Mon Jun 06, 2005 2:38 pm

please review this instruction set:

https://www.synthetikal.com/Rhodiums_pdfs/chemistry/----.rp.html

as you can see placebo recommends a coil condenser..

ApprenticeCook · DILLIGAF

Coil condensers are excellent for reflux, thats primarily what they are designed for.
The coils make a large surface area for the condensation of the material to occur.

Leibigs are however better for distillation in my mind over standard coil condensers (single surface) as the vapours on a slope as they are in distillation follow a outer most surface (the walls) which in leibigs is cooled where as in a single surface coil condenser the walls are not...
However if you happen to stumble across a double surface coil condenser you may aswell throw all the other condensers away as this one is far superior, there is 2 seperate cooling systems which are connected in series to still only need the inlet and outlet pipes be connected by the user. Think of these as a leibig and single surface coil condenser mushed into one piece of glass with the coolant flowing in series from the walls to then through the coil (or reversed depending on the manufacturer) then to the outlet.
These double surface jobs have uses in reflux and distillation.

-AC

loki · guinea pig

part of the problem with using coil and graham etc condensers for distillation has to do with the fact that only liebigs are able to be used in anything other than a vertical orientation, it is possible to get a U-bend joint that is suitable, but the apparatus becomes a lot taller, which may or may not be a problem. I don't think a coil or alihn or graham is suitable for vacuum distillation either, and not sure about double surface but there could be problems there too. i wouldn't want to test it out cos those other funny condensers are usually more expensive (cos they are harder to make).

slacker · Wed Jun 08, 2005 9:56 am

hey apprentice, is there anywhere online i could order one of those fancy condensers you mentioned? i never saw one of those around here and now you made me wanna go buy one.

slacker · Wed Jun 08, 2005 9:59 am

ApprenticeCook · DILLIGAF

whoops sorry... they are actually called jacketed coil condensers... ah depending on your country they are pretty expensive, around here they can go for $150-$200 for a 200mm long 19/26 socket and cone. But most glassware suppliers could get one / make one if you asked. Heres a pic... there is an external jacket connected in series to a coil for heavy cooling efficiency...

Coils are meant for reflux, loki is right, but as for the coil breaking under vacuum, mine works fine, you either applied the vacuum to quick or the coil had a small crack in the first place, they are very fragile so extreem care is required no matter where your using them... Use coils for verticle orientation (ie reflux) and use the liebigs for slope distillation. Ie use the right condenser for the use it was designed for...

-AC

loki · guinea pig

jacketed coil condensers (like, a combo of liebig and graham really) are probably more tough in the vacuum than the ones which the coil is on the inside, simply because the vacuum is sucking against the outer surface of the coil, which would produce less stress than the inside, because the inconsistencies in the circularity of the coil are more dangerous when the vacuum is inside it than outside it. the flat parts are where they break. vacuum on the outside is different, although the flat parts are still weaker, the amount of pressure pulling at them is much less, due to the outer surface having a larger surface area than the inside.

slacker · Thu Jun 09, 2005 8:07 am

The_Dude · Fri Jun 10, 2005 11:34 am

Graham condensers are SPECIFICALLY for high purity distillations.

THEORETICALLY, a bowl with ice in it can be utilised for refluxing.

Under heavy reflux a coil condenser can choke.

Bushroot · Thu Jul 07, 2005 4:43 pm

I reflux only using coil condenser and never expirienced any problems.
It gives the best cooling.
The temperature should be incredible (more than 350C) to choke that thing.

Ephoton · Thu Jul 07, 2005 5:20 pm

ive vac distilled with coils before many times actuall never had a problem
my vac is not that strong though.
never thought about the possibility of a coil condenser braking under hard
vacuum might have to try it one day (when I can aford it)