Dr. Robot Nick Nolte - 7-1-2005 at 08:22
From previous posts in this thread, I have gathered that Spiral/Graham condensers are virtually unfit for reflux work. While out surfing the web I
came across the "reflux condenser," that looks more or less identical to the graham condenser, or at least sharing some of the same
properties. Perhaps, somewhat can shed some light on the specific differences between these two types of condensers, that is "Reflux
Condensers", in comparison to "Spiral/Graham Condensers." Any illumination would be grossly appreciated.
Here's an example of an Reflux condenser:
<a href="http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3864869701&fromMakeTrack=true">Reflux Condenser</a>
vulture - 7-1-2005 at 08:42
In a graham condensor, the gasses and the condensate pass through the spiral, while in this model, the water passes through the spiral. That's
why it is suitable for reflux.
Dr. Robot Nick Nolte - 7-1-2005 at 14:05
OH! Eureka, now it all makes sense. I suppose I should have done a bit more homework, but regardless thank you much!
Mendeleev - 7-1-2005 at 14:44
In this particular model of condenser the water goes through the spiral and the jacket. I like the model where it is a tightly wound coil, around a
long thin cold finger.
Rosco Bodine - 7-1-2005 at 14:57
The preferred design for reflux would be one of the coldfinger types , because then you have no condensate from the outer jacket to drip downward onto
a hot flask . There are different variations of
this design . Some are a sort of coil condenser where the coolant flows through the coil . Other than that , the vacuum jacketed Allihn bulb type
is best , but expensive . For higher boiling solvent reflux a simple length of bare vertical column can be air cooled to provide reflux , and
enhanced by a spiral wrap of moist paper towel . A second flask inverted on the top of the tube can
provide a further cooling chamber to add more heat exchange surface if needed .
[Edited on 7-1-2005 by Rosco Bodine]