Sciencemadness Discussion Board

Distillation adapter choices

6.022x10^23 - 14-6-2010 at 09:28

SWIM finds himself needing to collect a few fractions under vacuum. Understanding a distillation is what is required the search was on.
Two different types have presented themselves and a consensus on what is the preferred model would be appreciated.

There seem to be two distinct types of cow’s.

A two piece unit


And a single piece unit


There has to be more of a difference than three and four arms.
Please advise which is your favorite and why.

Thanks,

The new guy.


[Edited on 14-6-2010 by 6.022x10^23]

DJF90 - 14-6-2010 at 09:29

SWIY should give up this whole cherade!



[Edited on 14-6-2010 by DJF90]

not_important - 14-6-2010 at 09:31

Perhaps SWIY could trouble themselves to post in person, then we'd have _two_ new guys.

While swimming is a summer activity, little is done around here due to the oil leakage.


Magpie - 14-6-2010 at 09:48

I can only see 3 receivers on each cow. Perhaps SWIY could explain which cow has 4 teats.

rrkss - 14-6-2010 at 11:02

SWIY obviously does not have any training or knowledge on this matter and definately should not be trying something advanced like fractional distillation under vacuum. Don't want the unit to implode causing lots of cuts and possibly severe burns + fire do you?

mfilip62 - 14-6-2010 at 11:18

It depends on what you want to do,but it looks like you are not pro,su just go with something with less parts.
Keep it simple.

6.022x10^23 - 14-6-2010 at 13:20

Wow, I know it was the first post but that wasn't the warm reception I had in mind.

nothing pertinent in TFSE for "etiquette" "new guy" or "first+post"

The pics were just some generic images I grabbed. Perhaps it appears in the first picture that the flasks are 120° apart, but the one I was looking at had them 90°.

Basically I am asking what are the different types used for so that I may make a more educated decision. I respect some of the above posters so I will take my new-guy lashing. As pointed out I am not a professional and I will acknowledge that I am still learning. Just asking a question here as I have read all previous posts that I could find on this subject.

Magpie - 14-6-2010 at 13:28

Has SWIY ever performed a vacuum distillation, or any distillation, for that matter?

A cow is used for collecting 3 or 4 cuts without having to break vacuum to change receivers. The one SWIY chooses depends on how important collecting 4 cuts vs 3 is to the distillation he has in mind.

It's not so much your question that lit us off as your use of SWIM terminology. We're trying to get away from that as it is heavily used by cooks. Cookery and terrorism have almost destroyed home chemistry.

[Edited on 14-6-2010 by Magpie]

6.022x10^23 - 14-6-2010 at 13:42

Yes, I have successfully performed many distillations at both normal and reduced pressures. I understand the qualification questions.
I know nothing compared to some, but to others I am competent.

I also understand the forethought in selecting a three or four udder-ed cow. I am just at a loss at to the two different designs.
There must be a reason one would chose a single unit that rotates in one plane versus an two piece unit that appears to rotate about a different plane. Do they have different names?

Here is a better pic from one of the posts I have read:

Quote: Originally posted by chemrox  
the whole cow setup

[img]http://www.sciencemadness.org/talk/files.php?pid=146257&aid=7173[/img]





[Edited on 14-6-2010 by 6.022x10^23]

Lambda-Eyde - 14-6-2010 at 14:29

The setup shown in Chemrox' picture allows it to be used in conjuction with a vertical Graham or Friedrich condenser. Simply adding a 105 degree adapter allows it to be used with a normal liebig condenser as well.

rrkss - 16-6-2010 at 09:57

I personally use a two piece unit because then the vacuum line does not interfere with rotation of the cow.

altech6983 - 16-6-2010 at 14:57

If I had to buy one it would be the two piece. No vacuum line interference and it looks easier to use overall.

zed - 17-6-2010 at 01:02

Mole-Man, the moderators here, hate the SWIM (someone who is me) lingo. Makes it seem like you are possibly a criminal type....A degenerate Hive-nik.

Around here, the archaic designation "I" is preferred. Folks just assume that in the province where you reside, you possess all required permits, and your activities are thus completely legal.

Welcome to Science Madness. Thanks for the pictures.

[Edited on 17-6-2010 by zed]

6.022x10^23 - 18-6-2010 at 12:06

Thank-you for the replies. This is just what I was looking for. I didn't know about the lingo.

**standing corrected**

rrkss - 18-6-2010 at 20:52

Just don't forget to grease your joints before you use vacuum. Otherwise you will have vacuum jumping all over the place and risk fusing your joints together

Panache - 22-6-2010 at 00:30

i am aware of the second one being called a 'pig', because it looks like a few piglets taking a drink from mum.

devongrrl - 22-6-2010 at 00:35

I agree with Zed, the only time I SWIM is when I put my cossie on and go to the pool.

When I used to collect different fractions I used a receiver pig onto which several miniature rb flasks could be attached and clipped using keck clips.
The "pig" could then be rotated when required to selected the different collecting flasks.

Contrabasso - 22-6-2010 at 09:22

Realistically there are always at least two ways round each problem. In some parts of the world these adaptors are called pigs in other places cows, but whatever the shape the function is the same and the type that you use may depend on your supplier's sources.