Biochemscientist - 18-8-2011 at 21:57
Is it okay to perform a reflux with a Graham condenser? Are there any advantages of other condenser types over Graham condensers?
hkparker - 18-8-2011 at 22:14
I don't think its recommended, as a reflux condenser will be more efficient and capable of handing large amounts of a liquid, while a graham condenser
might become dangerously clogged, but I have used one before for smaller scale reactions and with a lot of cooling it worked quite well.
starman - 18-8-2011 at 23:11
UTFSE this has been discussed at length.First of all there is often confusion over what constitutes a graham.In a graham the vapour passes through the
coil and water through the jacket.If you have one of these it is generally not suitable for reflux as it tends to flood and spit.Better an
ahlin,freidrichs or plain old leibig.
Bot0nist - 19-8-2011 at 03:10
I prefer an ahlin for reflux. The graham can't handle enough condensate and spews it our of the top. An ahlin is efficient at condensing vapor and has
enough diameter to allow the liquid to drain back down without pushing it out the top.
Arthur Dent - 19-8-2011 at 03:41
As stated above, some condensers are better suited for reflux, your Graham condenser is unfortunately the worst choice for refluxing.
Among the best choices would be of course a Vigreux column, depending on the temperature and quantity of the solution you want to reflux, it's
basically its only purpose. The Allihn is an excellent choice, and can be used with or without water running through it, depending on what you're
refluxing.
My personal choice is the Friedrichs condenser, because of its particular shape, it's very well suited for refluxing, I actually use that type of
condenser on top of my soxhlet apparatus. Again, it could be used with or without water running through it, and it makes for a really cool looking
setup in a geeky sort of way.
Robert
[Edited on 19-8-2011 by Arthur Dent]