Sciencemadness Discussion Board

Vigreux Column w/ side arm vs without - does it effect performance?

RogueRose - 13-6-2017 at 20:17

I'm wondering if there is any difference in performance between a vigreux column with a side arm and one without. Would the extra rise of about 50-80mm when adding the 3 way thermometer adapter effect the distillation performance at all?

I was looking at some setups and the ones with a vig column supply a vig column with a side arm where plain setups offer the 3 way thermometer adapter alone. I was considering the setup w/o the vig colum and ordering that seperately (straight column alone) or the setup with the vig column and ordering a seperate 3 way thermometer adapter.

If one piece needs to be ordered separately, is there any "extras" or beneficial qualities that should be looked for like PTFE thermometer holder or anything else that could make it more versatile or better?

Is there a benefit to a vig colum with a side arm or benefit to not having the side arm?



With side arm
vig 2.jpg - 457kB

With 3 way adapter only
vig w-out column.jpg - 543kB

Vig colum w/o side arm.
vig colum.jpg - 316kB

j_sum1 - 13-6-2017 at 20:43

Take my thoughts with a grain of salt since I have no experience with the side-arm version.

I think the one without will be more versatile.
* The overall column length will be greater.
* You likely already have a three way head adapter
* It enables different kinds of configurations more easily -- doubling condensers, mounting horizontally for use as an air condenser, or even packing if you so desired. Not sure if all of these are necessarily recommended but after a bad glassware day you might want to improvise.

My feeling is the the integrated unit is to save money for a separate adapter. This is false economy if it restricts you.

alking - 14-6-2017 at 08:00

Besides the potential for joint leakage and the slight increase in column length w/the adapter I don't see why there would be a difference. I second all the points j_sum1 said.

PirateDocBrown - 14-6-2017 at 16:43

This is what I got:

The flasks are 1000 and 500. Can't have too many flasks!

The column is 200mm.

I already had a Leibig, but can't hurt to have a spare.

No sidearm, just a regular distillation head and thermo adapter, both of which I had, but my old thermo adapter had the rubber fitment, this one had an O ring. Again, spares are good.



51g1HbRsBLL._SX342_.jpg - 30kB

Sulaiman - 14-6-2017 at 18:33

looks like a useful kit, nice.

"I already had a Leibig, but can't hurt to have a spare."

it is not difficult to use two condensers instead of one.
even if most of the condensation occurs in the first 1/3rd of the first condenser,
occasional mild 'bumping' is usually mostly 'caught' by the second condenser.
(based on limited experience)

P.s. your separate vigreaux and head is the choice that I would have made, more adaptable to other configurations.

the rubber tubing looks like the stuff that came with my kit ...
I threw mine away as it collapses and/or balloons easily
... imagine water spraying around and loss of cooling mid-distillation :o


[Edited on 15-6-2017 by Sulaiman]

PirateDocBrown - 14-6-2017 at 20:42

I use clear vinyl tubing for condenser feed.

One nice thing about the new condenser, is that my old condenser has tines, and can easily take packing to become a different kind of column, yet I still have the new condenser to be a condenser.

I also have a coldfinger condenser, which is handy for many things.

What I lack is condensers for special purposes, I have no Allyn, Graham or coil condensers. I also need better heating solutions, like a proper stirring heating mantle for ~1000ml RBFs. I have several working hotplates, but the stirrers are burnt out. I have one with a good stirrer, but weak heating. I also have a mantle, but it's only 250ml, and lacks stirring.

A few more things on my wish list: A Dean-Stark trap, a Claisen head, and some smaller 3-necks, around 250.

But I'm able to do many things!

Then, I have a huge wish list for chemicals. I'm trying to keep this hobby as cheap as I can.