Author Topic: What's Best?  (Read 3360 times)

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Drug_Phreak

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What's Best?
« on: July 20, 2004, 11:10:00 PM »
What's best for a HI/RP/E reflux.... a West condenser or a Liebig? Does it really matter which one a Bee uses? What's the optimal size?


ApprenticeCook

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From what i can see on images from google they
« Reply #1 on: July 21, 2004, 05:03:00 AM »
From what i can see on images from google they look the same...... Except a west condenser has a reduction in outer diameter of the water jacket.... huh? more efficiency with a faster flow of water through the limited space??
West condenser -->

Liebig condenser -->


For reflux you want an efficient condenser, so it just comes down to which one has the greater efficiency....
If what i said about the west condenser is true i would say it would be but the difference could only be a little with the same length condenser...

You want a long one... pref ~30-40cm long.

-AC


Drug_Phreak

  • Guest
Thanks for the info ApprenticeCook.
« Reply #2 on: July 21, 2004, 02:58:00 PM »
Thanks for the info ApprenticeCook. I see a lot of people using a West condenser for reflux, but then someone said that a person should use a Liebig because it has a smaller inner tube and the outer jacket is larger which cools the reactants better so then I started wondering. I think I even remember reading a while back that some king bee here said that a Graham condenser is the best for a reflux.


ApprenticeCook

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Look up the efficiency rate of each type and...
« Reply #3 on: July 21, 2004, 06:30:00 PM »
Look up the efficiency rate of each type and decide what you want, lieg's and west's are probably the elst efficient water cooled condensers... but it depends on what your doing....
For your method as long as you have the length you should be fine...

If you were doing something more volitile you would have like 50-60cm condenser maybe? or a double surface condenser, something with a very high efficiency rating.

-AC


drnasty

  • Guest
Go for the Graham!
« Reply #4 on: July 27, 2004, 09:36:00 PM »
I prefer the Graham over the other two.  Graham condensers are much more efficient because the coolant is pushed through a coiled tube, increasing the cooling surface within the condensing chamber.  However, they also tend to cost about twice as much as a West!  Therefor, I suppose if the West is sufficient for your applications and you're trying to conserve funds, you should go with the West.  I wouldn't even bother with the Liebig.


ApprenticeCook

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more efficient = more money spent...
« Reply #5 on: July 27, 2004, 09:53:00 PM »
more efficient = more money spent...

Cant expect to buy a racecar when you spend $17000 on a daewoo matiz can you?

If you look at the lab supplier info page of the condensers they usually have the cooling surface area listed with it....
Check the different types but no matter how good they are you need to get a decent length, esp for volitile materials as they require not only alot of cooling power, but they may take a long time to cool down (condense) so get a decent efficiency and a decent length suitable to what your doing and you will be fine.

-AC


Rhodium

  • Guest
Graham condensers are easy to overload
« Reply #6 on: July 28, 2004, 05:24:00 AM »
Graham condensers are easy to overload if used as reflux condenser due to the small diameter inner tube, and this causes excess condensate to splatter and pressure might build up.

Also see

Post 281432

(Rhodium: "What Graham condensers are good for", Methods Discourse)



Rhodium

  • Guest
Graham condensers are easy to overload
« Reply #7 on: July 28, 2004, 05:28:00 AM »
Graham condenser are only used for for downwards distillation, see see

Post 281432

(Rhodium: "What Graham condensers are good for", Methods Discourse)
.

If you try to reflux using one of those they will flood directly, as the coil is so thin...


drnasty

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I see ...
« Reply #8 on: July 29, 2004, 04:37:00 AM »
I have done this before.  I broke one of my condensers and I figure it is for this exact reason.  Thanks for the info.


Snakebyte

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A west condensor has more suface area so it...
« Reply #9 on: July 29, 2004, 03:43:00 PM »
A west condensor has more suface area so it would be better for refluxing than a liebig but a liebig would be more efficient for distillation as there would be less waste.  Allihn condensors are far better for refluxing than both.


Drug_Phreak

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I forgot to check this post... lol.
« Reply #10 on: July 31, 2004, 04:11:00 PM »
I forgot to check this post... lol. Too busy being a worker bee.  ;)  Good info here... thanks. It seems best for me to get a 300-400mm Liebig, a 300mm West or Allihn, and a 600mm West or Allihn.


ApprenticeCook

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Get your liebig for distillations....
« Reply #11 on: August 01, 2004, 02:30:00 AM »
Get your liebig for distillations.... a nice 40cm would suffice for nearly everything.

Allihn for distillation would be a pain, the distillation gets trapped in the bulbs... and hence removes the functionality of a fractional distillation.. use the Allihn's for reflux.... 60cm should do it well.

Maybe even instead of a second Allihn, a double surface condenser for more delicate distillations, just so you have that extra edge of cooling capacity... a 40cm one of these should be fine too....

With these three condensers (40cm liebig, 60cm Allihn and 40cm double surface) you would have a nice varied collection for pretty much everything you want to do, reflux's and distillations.....

-AC


Drug_Phreak

  • Guest
OK. SWINM is tired of using ghetto reactors.
« Reply #12 on: August 01, 2004, 05:08:00 PM »
OK. SWINM is tired of using ghetto reactors. Time to go to the next level.