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condensers

Magpie - 26-8-2004 at 08:15

I'm hoping this thread can be a general discussion of condensers. There are a great many condenser configurations and the inventors must have had something specific in mind when they conjured up their designs.

I have an old condenser given to me over forty years ago. It is in a CENCO box that says "Liegig's condenser." But I don't think it is a Liebig. It has an 8" long shell containing a 1/4" diameter helical inner (vapor) tube. Is this a Graham? What is it specifically designed for? Thanks for any help that you can give.

Organikum - 26-8-2004 at 09:10

Its a spiral condensor, useful for condensing volantile low-boiling compounds, from ethylalcohol to ethylether, DCM, benzene etc. Very effective cooling but rather high back-pressure - not so good for distillations with lots of BUMPING.
Absolutely not useful for reflux.

Magpie - 26-8-2004 at 09:37

Thanks, Organikum. That is helpful information.

The Vigreux and packed columns are used for fractional distillation, right? Which is the best for this, or does that depend on the application? What is the Vigreux specifically designed for?

The reflux condenser and the West condenser are similar but the reflux condenser is the shorter, fatter one, correct?

vulture - 26-8-2004 at 09:44

Vigreux column is fast with high flow rate, but less efficient separation. The boiling ponts should atleast be 20C or more apart for a 30cm one.

A packed column is very efficient but has a very low flow rate.

In theory, you can use any condensor for reflux except the spiral condensor because this one will propell liquid out the top.
However, it's obvious that a liebig cooler is not very well suited for reflux because of laminar flow.

Organikum - 26-8-2004 at 10:00

Colums are something quite different than condensors - please dont mix things up.

A reflux condensor can be anything which represents no or almost no resistance to the gases, say the "free aperture for flow" has to be similar or bigger than the opening to the flask. Or it may be blown out or even destroyed. Happens quite often btw.

For the columns you may have a look into Vogel´s 3rd where this explained in detail, vultures explanaition was basically right though.
The Vigreux is the quick-shot for the lab, no good separation but easy to clean, and cheap. The Hempel - the tube filled with Raschig-rings or similar has a better separation but holds back lots of volume - not good for smaller amounts to distill, but perfect when time is not important and you process quantities of something. Also cheap and easy.
The "spinning band column" is the master, but thats not a cheapo in special when you go for higher temps and need a platinum or tantalum band. Uh.

And as we mixed already columns and condensors I cannot resist to throw in the fine "reactive distillation" - thats a good one!

Or the destructive distillation.
Or....

[Edited on 26-8-2004 by Organikum]

Mendeleev - 26-8-2004 at 13:45

Why would you need a graham condenser for distilling ethanol? I wouldn't use a graham condenser for anything which boils over 40 C, it's just redundant. Thus, out of the common applications I use it for dichloromethane, ether, and acetaldehyde. I have heard a little about using acetone/dry ice mixtures to condense gases such as methylamine and ammonia, but I don't know very much about this. As for reflux condensers, your standard inner coil, outer jacket are pretty nice. There are those with a larger coild for low vapor pressure solvents. Friedrich condensers are pretty nice and there was one on sale on ebay, ground glass, for $48.50. Then there is the king, Go to http://www.chemglass.com/index.htm and search for product number CG-1215-C.

[Edited on 26-8-2004 by Mendeleev]

Graham

MadHatter - 26-8-2004 at 22:42

Magpie, that does sound like a Graham condenser. My Liebigs are
straight tubes. I have both in my collection. Picture enclosed. The
Grahams are on the top, the Liebigs are on the bottom. The Friedrich's
is just below the Graham's. Sorry, I need to get a better snapshot.
Look in the "whimsy" section under "Lab Photos". Can't seem
to find that goddam browse button again.

[Edited on 27-8-2004 by MadHatter]

Picture

MadHatter - 27-8-2004 at 01:30

Magpie, sorry about the color. The condenser is actually clear.
Picture of my Friedrich's condenser:

FRIEDRICH.jpg - 146kB

vulture - 27-8-2004 at 01:32

Isn't that a condensor for a rotavap? (asked the same question in whimsy, but it's more clear here)

Condenser

MadHatter - 27-8-2004 at 01:54

Vulture, mon ami,you have the response time of a bolt of lightning !
The only thing I can tell you is that it's made by LabGlass out of
Vineland, New Jersey with a 24/40 joint on the sideneck. It looks
like a Friedrich's but I could be wrong. Maybe you know more about
it than I do. It really doesn't matter to me - it's another beautiful
piece of glass in my condenser collection ! It appears to be unused
but it sounds as though you know more about it than I do. I'd be
interested in any info you may have on it !

Babylon....

Organikum - 27-8-2004 at 01:59

Due to the wars the english and americans didnt love the germans anymore and started to rename pieces of glassware claiming it being own inventions. Like the siviets claimed that motorcars were invented by a certain "Ivan Automobilowitsch" ....

"Liebig" mutated to "West"
"Spiral" to "Graham"
etc .......

ORG

Oh, a "Intensiv" aka "high performance" - condensor with an outer water-jacket is a "Friedrichs" .
And the sameone without is a "Dimroth".
I think

And yes the one with the outer jacket are used in Rotovaps.

There are all pics and more, reaction setups etc. on the ftp. Almost every information I have is on the ftp. Just look. You will be astonished although it takes some digging, but its worth the effort as I believe.

[Edited on 27-8-2004 by Organikum]

Organikum - 27-8-2004 at 02:17

here:

kühler.jpg - 25kB

Organikum - 27-8-2004 at 02:24

"Big Reaction" setup:

grosse_reaktion.jpg - 35kB

vulture - 27-8-2004 at 03:24

Well, the cooler madhatter shows here is based on the intensive principle, but the dimensions have a different ratio than the normal lab ones, it's wider or shorter. The very wide ones with several connections (opposed to 2 for a lab one) are usually rotavap coolers.

Although the 24/40 joint doesn't point in that direction. Could you perhaps provide a picture with some sort of scale?

You might want to search on rotavaps, or rotating evaporators. A setup used to distill off solvents under vacuum using a bath wherein the flask rotates. This is a very clean and safe way of evaporating to dryness. Büchi is the leading company in this field.

Organikum - 27-8-2004 at 05:47

Rotovap:

rotovap.jpg - 46kB

neutrino - 27-8-2004 at 05:47

Well, as long as this thread is about condensors, I have a question. What do you use to condense vapors when distilling something with a bp? (Somewhere in the 250*C range.)

Organikum - 27-8-2004 at 06:17

250°C bp ?
A simple tube - aka "air-cooled condensor" suffices, or use a Liebig with warm water.

The temperature of solidification aka melting point (mp)) gets more interesting here. If your condenspr works to well you will clog it.
Then you may resort to "short way distillation"

kurzweg-feststoffdistill.jpg - 33kB

vulture - 27-8-2004 at 07:10

Or the infamous "banana" cooler comes to mind.

This would be a really good piece for madhatters collection.

neutrino - 27-8-2004 at 10:25

I'd heard about the simple air-cooling, but I didn't believe it because it doesn't sound like there would be much cooling going on, just air slowly moving by... Warm water!? Wouldn't that cause bumping in the condenser as it boiled?

Also, doesn't the rule about the inside and outside of a glass vessel being less than 30*C apart also apply here?

Organikum - 27-8-2004 at 11:40

neutrino, you have so many misconceptions that its impossible to clear this up, sorry. Download the Vogel´s 3rd from the ftp or Rhodiums page and read the chapter on distillation please.

vulture, thats a "sabre" no "banana"

neutrino - 27-8-2004 at 16:17

I have actually already read that chapter, there wasn't anything on condensors in it. Just bumping, vapor-pressure calculations, and the different types of distillation. Can you please elaborate on these misconceptions? I think there's some simple big thing I'm missing here...

:edit:
Wait... I think I know what you're thinking... I know that the liquid to be distilled doesn't boil in the condensor!

What I was thinking was that the cooling water would heat up to about 30*C less than the distillate vapor (due to the 30*C rule), which would still be way over the boiling point of water, so the water would boil. Seeing as you probably couldn't pack a condensor with boiling stones, the water would probably boil irregularly in the jacket and thus constitute bumping. Now, judjung by your reply, the inner tube in a condenser can take more than a 30*C difference between the inner and outer walls?

[Edited on 28-8-2004 by neutrino]

Organikum - 28-8-2004 at 02:05

The water in the cooling jacket is - except for air-cooled condensors or Dewar-type condensors - circulated by a pump.
So what I wrote said - understandable to everybody but you, neutrino - that the condensor should be fed with warm water circulated by a pump.
The rule says that the difference between cooling water and the bp of distillate should be AT LEAST 30°C - not max.

That Vogel´s 3rd says nothing about condensors, isnt this embarrassing? Whatta fucker this Vogels idiot must have been to leave this out!
Unbelievable this is.
And not true.
At page 48 of Vogels 3rd are the different types of condensors depicted, on page 47 they are described and their uses named.

neutrino, you are walking thin ice. You are either not able to use the INDEX of a book and to look there for "condensor" what would speak of VERY limited intellectual capabilities, or you are fucking around with me, what I dont like (includes consequences of course). For sure you are EXTREMELY unpolite.

You now may choose: You change your behaviour and we forget this, or you go on and we forget you.
Make your choice!

ORG

neutrino - 28-8-2004 at 05:02

I knew about the circulation and such, I was just misinformed about the temperature gradient. In your first post, I thought you meant the distillation section specifically, and not the condensor section. That section also didn't mention the gradient, so I was lost. Thank you for clearing this up for me.

I say we just forget this little misunderstanding and go on with our lives.
P.S. How was I rude? I certainly wasn't trying to be. I'm sorry if I was.

[Edited on 28-8-2004 by neutrino]

Senjoro Nie - 28-8-2004 at 08:55

I looked at the condenser Madhatter posted, and it looks like it goes with a Soxhlet extraction setup. The large bottom joint plugs into the extractor body's upper joint, avoiding the need for an adapter (i.e. if using an all-24/40 condenser with a 45/50 extractor).

Organikum - 28-8-2004 at 10:18

Ok, lets start over. (I never said you were "rude" btw. - "unpolite" is far less strong in my understanding)
Neutrino, what are you want to say with "distillation-section"? We were talking condensors - you and I - nothing else. Do you refer to whats happening in a column so attached? This would be called "rectification".
These two things should not get mixed up as I wrote before as this is a mayor point of confusion.

For your high-boiling substance you may use a short Vigreux-COLUMN (15cm) and then a condensor setup as told above. Any longer column will need good isolation, either a vacuum-jacket (preferred) or glasswool insulation and distillation will get slower.

PS: the "15cm" refers to the ACTIVE part of the column where actually rectification takes place, the grounded joints etc. dont count to the length.

vulture - 28-8-2004 at 10:24

Quote:

I looked at the condenser Madhatter posted, and it looks like it goes with a Soxhlet extraction setup. The large bottom joint plugs into the extractor body's upper joint, avoiding the need for an adapter (i.e. if using an all-24/40 condenser with a 45/50 extractor).

I don't concur. The condensor has too many connections for this. I have such a soxhlet condensor myself and it simply is a jacketed reflux condensor with one larger joint.

EDIT:

Quote:

PS: the "15cm" refers to the ACTIVE part of the column where actually rectification takes place, the grounded joints etc. dont count to the length.

True, but rectification takes place on any vertical surface, just not that efficient because of laminar (or stagnant) flow.

[Edited on 28-8-2004 by vulture]

Organikum - 28-8-2004 at 10:30

If the compound you are thinking on is something with properties like safrole you cannot distill thus without decomposition, you need a strong vacuum-pump for this. This is true for many of the natural oils.
You can "freeze out" safrole though. (and many other natural oils).

Other oily substances like phenyl-2-propanone as an example are better steam-distilled as they are quite well volantile with steam (an external steamsource is preferred). This substance for example can be distilled at STP (standard-pressure, no vac-pump) with only minor decomposition taking place, but I would recommend to steam-distill first and tu use direct distillation if the steam doesnt suffice to produce a clean enough product for further experimentation.

There exist some rules of thumb in distillation and a thousand exceptions in realworld. Its a mess.

Senjoro Nie - 30-8-2004 at 12:35

Quote:

Originally posted by vulture
I don't concur. The condensor has too many connections for this. I have such a soxhlet condensor myself and it simply is a jacketed reflux condensor with one larger joint.

My Soxhlet apparatus came with a Friedrichs-type condenser like the one in Madhatter's picture.

Alas it is now broken, so I use an all-24/40 Friedrichs with a size adapter instead.

Most Soxhlet condensers are what you described, usually an Allihn-type condenser. Madhatter's is a Friedrichs-type -- instead of an outer cooling jacket, there is instead a coolant-filled cold finger surrounded by a glass outer wall. That's why the connections look so odd. The topmost hose barb is the coolant inlet, and the side hose barb is the coolant return. The ST joint on the side mainly serves as the vent, though it can accept a ST drying tube (keeps condensation out) or it can be used as a distillation inlet. The oversize bottom ST joint (34/45?) more or less gives it away as being intended for a Soxhlet apparatus, but certainly it could be used for reflux in a large flask.

Personally, I prefer the Friedrichs-types because the cold finger is protected from the air by the condenser's outer wall, so the coolant absorbs less heat from ambient air. I use an ice bath and pump, so it means I have to use less ice. Plus, the spirals on the cold finger and the narrow space between it and the outer wall gives very good condensing efficiency, useful for those low-boiling solvents.

The downside is that the top hose barb is extremely prone to being broken off by accident. Not good, especially considering that Friedrichs condensers cost a good bit more than the more common Allihn or Liebig types!

EDIT: Here's one from Fisher's website: https://www1.fishersci.com/Coupon?cid=1328&gid=145730&am...

[Edited on 30-8-2004 by Senjoro Nie]

Mendeleev - 29-12-2004 at 22:02

When distilling a low bp liquid like ether or DCM, and using a graham condenser, does the graham condenser have to be in a vertical position? It looks as if the liquid, once condensed, would accumulate in the dips in the spiral if it was held like a standard setup using a liebig condenser at a slight angle.

vulture - 30-12-2004 at 05:07

Yes, it has to be vertical. Also, never use it for reflux, unless you want liquid shooting out at the top.

Mendeleev - 30-12-2004 at 09:03

So is there any real necessity in a graham condenser for things such as ether or DCM? I mean if you can get ice water to circulate through a 400 mm liebig or a 300 mm allihn then there shouldn't really be a need for it in these applications. I doubt it will improve efficiency that much.

Organikum - 30-12-2004 at 11:56

If you dont overdo the heating and distill slowly in special with a column an ice-water cooled long Liebig suffices. A copper made Liebig is very good for low-boiling solvents, but one of glass will work too.

/ORG

Quince - 17-2-2005 at 15:09

I've got three questions for this thread.

Why is it a problem if distillate collects in the dips of a tilted Graham condenser? Wouldn't pressure buildup push the liquid plugs through, and any remaining be drained by standing it upright at the end of distillation? This would be even more effective if vacuum is used. I'm asking as I have one on the way, and I'd not be happy to have to get a second condenser (I was trying to go for a minimalistic setup).

My next question: I still don't understand how Dewar condensers work.

Finally, I can't figure out how the solvent recovery condenser at the bottom of http://www.uicoglass.com/condensers.htm works.

Thanks in advance for answers.

neutrino - 17-2-2005 at 20:10

Dewars are simple: the vapor is introduced at the side, condenses on the cool inner part (in which the cooling mix is sitting, but on the outside of the condenser), and drips out the bottom.

HNO3 - 17-2-2005 at 21:58

The solvent recovery condenser is what you put on a RBF after your soxlet extraction is performed. The solvent condenses and runs to the bottom of the condenser, where it is removed through the stopcock controlled opening.

Quince - 17-2-2005 at 23:53

Thanks. So only my tilted Graham condenser question remains. (I only have angled attachments, and no money now for more glassware.)

Quince - 23-2-2005 at 22:59

Anyone? I'm stuck with the Graham for now. I was thinking I could make a U turn with the two angle adapters, and have the Graham vertical over the collecting flask, but the problem is that I only have the two adapters, one of which has the protrusion for attaching the vacuum hose, and that of course has to be on the collecting side. So I guess I'm screwed, unless I find a third straight adapter with a vacuum connector, or maybe I can sort of tilt the whole setup 45* so the condenser's about vertical, and use less liquid volume in the boiling flask so it doesn't reach the throat.

Also, is aquarium air tubing strong enough for vacuum? I ask as I can get it very cheap, and if it were to corrode from HNO3 I wouldn't care as it costs little to replace. What about silicone tubing as used in glow fuel lines for RC models? I also have a bunch of PTFE Teflon tubing but the stupid thing is barely flexible and creases when I try to bend it.

[Edited on 24-2-2005 by Quince]

mick - 24-2-2005 at 12:57

The dewar condenser can also be used with salt + ice mixture etc.
The standard cold temp stuff is dri-ice + actone or iso-propanol at -78oC and then slush baths with liguid nitrogen. Reactions are carried out at -78oC because that is the easy option but they might work at -50oC or some thing. My own home freezer is on the way out, no temp. control and it makes a funny noise when it cuts out but the temp. gauge reads below -40oC and it is cold. I have seen -55oC refidgeration boxes and even -104oC boxes. Polyetheylene is good at low temp. and fairly solvent resistant, polyproylene is good but not as good.

A quick question, what would be the best thing to put in some small sealed containers that could be recycled with freezing down to -40 or 50oC and be able to cool down a cooling bath to that temp (used as low temp recyclable ice cubes??). I have been thinking of a low molecular wt polyethylene glycol.

Back to Quince's question, silcone tubing seems to be very chemical resistant but soft and might collapse under vacuum unless heavy walled, or feed it through a bit of stronger tubing of slightly larger diameter and that should stop it collapsing.

For good filtration under vac. you need to pull the liquid through the filter and collect the solid, low vacuum will do this. If you use high vacuum, the liquid will evaporate in the filter and block it up (the more vacuum, the more blocked up filter you might have). A good way to do vacuum filtration, especially with volatile solvents, is to put the vac. on and then close the vac line and when it stops filtering put a bit more vac on it.
mick

To bend PTFE, if you warm it up to around 200oC you can usually get a long bend in the tubing, cool under water. If the PTFE goes clear then it will probably collapse. If you start smelling anything then you might have HF so be careful.
mick

[Edited on 24-2-2005 by mick]

Quince - 1-3-2005 at 14:51

Can I assume my Graham condenser will withstand vacuum from an aspirator? I'd hate to find out otherwise the hard way...

HNO3

MadHatter - 1-3-2005 at 18:48

Quince, I can't answer your question about vacuum for a graham condenser as I've
never used any of mine in that type of application. I've always used liebigs.

As for plastics that will stand up to HNO3, a quick google revealed that Kel-F, Kynar,
Teflon, and Viton have excellent resistance.

UhhKaipShaltaBlet - 17-3-2005 at 03:30

OK, I have question. Is Graham condenser suitable for HNO3 distillation ? I think Condensed(Sp?) HNO3 Vapour will drip into lowest "ring" point. Or it will be pushed by another gas portion coming ? I think if vacuum used it will suck that distillate wich can get up. Or I Should use Liebig condenser ? Here is the pics of Graham.
http://img.photobucket.com/albums/v281/formyfaFire2/PICT0023...
http://img.photobucket.com/albums/v281/formyfaFire2/PICT0022...
http://img.photobucket.com/albums/v281/formyfaFire2/PICT0021...

Dave Angel - 27-3-2005 at 18:33

Just a few remarks on nomenclature here:

Is the Graham type condenser not that which has the coil carrying the coolant? A google image search gives mixed results in that both coolant coil and vapour coil are given as Graham types. My glassware catalogue would seem to indicate that the latter (or a very similar condenser with a vapour-coil anyway) is actually known as an Inland Revenue (!) condenser; must be a UK thing.

As for your situation UKSB; I'd go with the Liebig and vacuum - that should be fine. In fact, you'd be okay without the vacuum for HNO3, though you may find you'll need to purge it of nitrogen oxides if you want white nitric. My thinking about the vapour-coil pattern condenser is that if one did not have it vertical, there would be welling of condensate in each dip.

neutrino - 28-3-2005 at 03:28

I’ve always seen a graham as the kind with vapor going through the coil. If you save coolant going through the coil, you have a reflux condenser.

Dave Angel - 28-3-2005 at 07:38

Perhaps it is a UK thing, and Grahams over here are coolant-coil, whilst yours are vapour-coil:

UK

USA

Coil condensers

MadHatter - 28-3-2005 at 08:55

I have both types of condensers in my collection. The condensate does form in the
coils of a Graham. My Dimroth condenser, as identified by Vulture, has the coolant
flowing through the coils and is a reflux condenser.

Dave Angel - 28-3-2005 at 10:03

Sō-nano? ^^

Equally, I could state that it is coolant that flows through the coils of a Graham as I own a Graham as per catalogue and quickfit code - but that does not make either of us internationally correct!

If I write about using one in any procedure I will be sure to make my description suitably... descriptive.

Coils

MadHatter - 14-4-2005 at 18:18

Good point ! I look at it from what is probably standard lab method of use but there's
nothing saying it couldn't be adapted to work differently based on the application.
I've used inverted flasks to act as reflux condensers to make booze. This is of course
before I got my stills.

Quince - 14-4-2005 at 20:27

Someone mentioned Liebig vs West condensers above. This is not just a regional naming difference, they are actually different. As opposed to the Liebig, the West has a wide inner channel and narrowed outer jacket, forcing a high flow rate and surface area of the coolant.

BTW, does using a Vigreux column help separation when distilling ethanol from say, wine? How do I figure out the proper amount of insulation to put around a Vigreux, i.e., what's the correct temperature distribution along the column?

The_Davster - 5-7-2005 at 19:48

Many of you have mentioned in other threads that you use pond pumps to run cold water through your condenser. I bought a 68 GPH fountain pump and it does not put nearly enough water through my 20cm 19/22 leibig. What would everyone recomend in terms of GPH or LPH that would work well for my condensor?

S.C. Wack - 5-7-2005 at 21:07

Don't know what to say. Mine is a 60 gph Beckett rated for a foot of lift, 40 gph @ 2'. Works fine on 400 mm Liebigs, with the pump at the same level as the receiver, the receiver is usually in the recirculating tank. Works the same with ice or steaming hot water. They don't come any cheaper than this one, AFAIK.

It has never liked being taken out of water after being shut off, though. It has to be smacked or vacuum applied to the other end of the condenser to get the air out, but then runs fine after the air in the pump gets out. So I keep it in a glass of water when off to prevent this, if I remember to do so.

bio2 - 23-7-2005 at 21:57

Not sure of the GPM but I use one of those bathtub pumps with the suction cups for water massage as a condenser circulator from a beer cooler tank.

Lifts the water about 5 feet and still produces adequate flow. At 2 foot lift it needs throttling a little.

ADP - 2-10-2005 at 07:19

Sorry to bump an old thread but what is the difference in performance of a west condenser and a liebig condenser. Which one would be more useful for let's say nitric acid distillation or something like that. Would there be a noticeble difference in performance?

Quince - 2-10-2005 at 15:50

The West condenser has a larger heat exchange area due to the large diameter inner tube. It's what I use, and I like it better than the Liebig.

This has already been mentioned a couple of times on the forum.

[Edited on 2-10-2005 by Quince]

chochu3 - 6-3-2006 at 20:54

To ADP:

The west condenser inner tube is thinner than a liebeg's inner tube and is the western standard of the distillation column which was to be improved over what the liebeg was and is used for. In other words the west condenser is supposed to be more effecient at cooling the distillate because of the thinner tube inside.

[Edited on 7-3-2006 by chochu3]

Quince - 6-3-2006 at 21:37

What the...
Yes, the glass is somewhat thinner, but the larger diameter of the inner tube is the main factor, increasing heat exchange area. Which is, what I posted, and has been said a bunch of times over the forum. Why the hell did you wake such an ancient thread?

chochu3 - 7-3-2006 at 16:48

WTF because its a old thread I can't put my own input or what. Do you think you own where, when, or how I can post. In that case then your a punk bitch and your just another punk in my book. I didn't say you were wrong but it also depends on the inner surface being thinner too. Or maybe your upset cause you assume I think the west condenser is more effecient than liebeg's condenser and you assume I'm being bias. In that case I'm sorry I made western created things look better than the old stuff made in the old world. Now you can reply to this message and say whatever you want or must but I could care less cause your not my mother or father to tell me what I can and can't do and another thing you'll just contribute another useless post which doesn't help in the spread of information. I rest my case.

As I said to somebody who wasn't you, it also helps with the tube being more thinner and also whatever somebody who is you said also holds true.

I apoligize if I have offended anybody; I've been here since the summer of 2003 and being visisting this board since. This is a great forum and this will be the last time I ever post a reply as the one above.

[Edited on 8-3-2006 by chochu3]

Quince - 9-3-2006 at 14:41

Use an aquarium pump. You can get a 200 GPH powerhead for under $20.

Endimion17 - 27-6-2012 at 10:30

Has anyone of you ever encountered a Femel condenser? Stupid Google won't even let me search for it because it constantly thinks I'm looking for a "female" one and thinks it's knows what I want better than myself.

Here's a sketch from one catalogue.

I've seen it in one old teacher's laboratory manual where it's used for just about anything, instead of a Liebig condenser. It doesn't seem to be very effficient and it looks kind of stupid to me.

(BTW, I've been reading the posts here and I agree with Organikum about the so called "West condenser". It's nothing but a slightly modified Liebig condenser. The name "West" is unknown outside English speaking countries, that's one of the clues. The whole world calls it a Liebig condenser.)

Diablo - 27-6-2012 at 11:04

Google will let you search for it if you click "search instead for femel condenser"
It looks a lot like a modified version of a retort.

Endimion17 - 27-6-2012 at 11:15

No, it doesn't let me do anything. It probably has something to do with our different locations.
Showing results for "female condenser"
No results found for "femel condenser"

Oh, silly Google.

I wouldn't say this is similar to a retort. The pear-shaped part is the condensing vessel, not the evaporating part.
It's like a double walled pear, pierced at one spot, connected to the right tube. The space between the walls is where the coolant flows.

The leftmost part is the connector for the receiving flask, and I assume it's connected to it with a wide rubber band, as it appeared in that old manual... A weird setup, indeed.

watson.fawkes - 28-6-2012 at 05:06

Quote: Originally posted by Endimion17

Has anyone of you ever encountered a Femel condenser?

Likely named for Jean Fernel, the 16th c. polymath who coined the terms "physiology" and "pathology", and the author of the first serious treatment of physiology (in the West) after Galen.

The shape of the condenser fits Fernel's chronology. It's shaped like a traditional still head known as a "pelican", whence images of pelicans in contemporaneous alchemical-allegorical images. The difference between this condenser and the pelican is the water-jacket sheath. If this is right, then Fernel would be the inventor of water-jacketed cooling, in addition to his other achievements.

Endimion17 - 28-6-2012 at 07:49

Could it be that m in "Femel" is actually rn? I can totally see how such an error could've be generated because of a bad printing job. I have no idea where to look for such obscure information. Old book section in a huge university library?

One thing I don't understand. Why the hell would this condenser be used in a laboratory manual printed after the WW2? If it's really Fernel's condenser, it's totally absolete. Liebig condensers were already common even during the 19th century...
I'll scan it as soon as I can.

The plot thickens.

99chemicals - 28-6-2012 at 08:06

This is kind of irreverent but could you use a Graham condenser horizontally? Would the gasses push the condensate up the bends? and kind of start a siphon?

Hexavalent - 28-6-2012 at 08:11

I'm certain that this has been discussed somewhere before, 99chemicals....and the answer is 'it depends'.

Funkerman23 - 28-6-2012 at 08:32

This is just my opinion..so I may well be another noise source. But with all the questions regarding what condenser if best for what, why not have a sticky posted on the subject? or at least a sticky with a thread directory for these kinds of FAQ's? I know I have asked questions more than a fair few times looking for a proper"ether Condenser". Vogel's is a great reference but it does sometimes fall short.The Site's search engine isn't stellar either but I digress.

99chemicals - 28-6-2012 at 08:48

Quote: Originally posted by Hexavalent

I'm certain that this has been discussed somewhere before, 99chemicals....and the answer is 'it depends'.

Can someone elaborate?

Endimion17 - 28-6-2012 at 10:37

Liquid inside a spiral cooler increases pressure inside the distillation flask, leading to increased temperature. That might pose a problem if the thing inside it is prone to thermal decomposition at elevated temperature.

Also, it might lead to more bumping. The condensed liquid squirts out, making the pressure inside the flask go up and down, which leads to violent boiling. You don't want that with things like ether.

Spiral coolers are meant to be positioned vertically or at a steep angle. They're not suitable for refluxing because they choke easily. I don't see why would anyone want to buy a spiral cooler unless they're doing something special. Yeah, it looks cool, but it's expensive and when you get it, it isn't that awesome. Liebig is enough for the majority of applications.

Liebig cooler, Vigreux column, air cooler (empty Liebig can be used instead). That's pretty much all you need.

bahamuth - 28-6-2012 at 11:43

Quote: Originally posted by Endimion17

Has anyone of you ever encountered a Femel condenser? Stupid Google won't even let me search for it because it constantly thinks I'm looking for a "female" one and thinks it's knows what I want better than myself.

Here's a sketch from one catalogue.

Search phrase "Alambique de FEMEL" gives many hits.

One site mentioned that the distillation of Tetra (Carbon tetrachloride) as it's main purpose, and why so I have no idea..

Endimion17 - 28-6-2012 at 13:40

Holy crap, that's it. I think this is the first time I'm seeing a real photograph of it. Thanks, bahamuth.

Yes, alembic was one of the first things that came up my mind while looking at the manual years ago... They're very similar. Now why would someone want to use this thing? It's so old and doesn't look very efficient.

Once again, thanks. Great find.

[Edited on 28-6-2012 by Endimion17]

watson.fawkes - 29-6-2012 at 06:20

Quote: Originally posted by bahamuth

Search phrase "Alambique de FEMEL" gives many hits.

Indeed it does, and they seem to be all in Portuguese. Proper names that are as old as this one is to my eye did not have canonical spelling until more recent times. This one, in particular, as Portuguese, strikes me as deriving from the era of Moorish Spain, when Arab science flourished.

In any case, my other hypothesis is that the name is Nicholas Flamel, a more likely candidate, since he had quite the reputation as an alchemist. Searching for "Flamel's alembic", amusingly comes up with a ton of reference's to Hugo's The Hunchback of Notre Dame. I don't know if it would have been invented by him or merely named after him later; modern practices of authorship assignment were not present in Flamel's time.

Mildronate - 30-6-2012 at 05:15

Quote: Originally posted by watson.fawkes

Quote: Originally posted by bahamuth

Search phrase "Alambique de FEMEL" gives many hits.

If Flamel invented this cooler, it was before Liebig cooler

Endimion17 - 5-7-2012 at 13:56

I don't own an air condenser with a ground glass joint, so I was thinking of using Liebig condenser instead, without the water. The problem is that its jacket makes it useless, as the heat accumulates inside. Air is an excelent thermal insulator. The condensing ring would soon leave the condenser and fumes would start exiting the distillation apparatus.

What if I blow air through it, using an electric pump or just a large baloon with a stopcock? That seems like a fairly safe and efficient alternative, but hey, everyone can make mistakes. Or I could just fill the jacket with water and plug the lower part.
Does anyone have any experience with such non-conventional setups?

[Edited on 5-7-2012 by Endimion17]

Pyro - 5-7-2012 at 15:08

how about water at room temp?

Endimion17 - 6-7-2012 at 02:54

You mean circulating the room temperature water? I don't have a pump. I could buy it, but then I could buy an air condenser, too.

watson.fawkes - 6-7-2012 at 05:40

Quote: Originally posted by Endimion17

What if I blow air through it, using an electric pump or just a large baloon with a stopcock?

It should work just fine. Just beware that air isn't a particularly good heat transfer medium, so the condensation rate won't be all that high. Water is much better for transferring heat. If you've already got an aquarium air pump, try it. I doubt a balloon will do much; there's not enough air mass to move much heat.

You might want to make a shakedown run. If you've got a variable heat source (say, variac + mantle), put a solvent of interest (say, water) and put it under reflux using the air condenser. Above the open top, put a watch glass with some ice; this acts as a vapor detector. Now turn up the heat under your boiling flask until you get vapor condensing on the watch glass. That heat setting has now overtaxed your condenser. Run your reaction of interest with this capacity limit in mind.

Endimion17 - 6-7-2012 at 06:35

Well, air condensers do serve a purpose. They're used for condensing liquids with a boiling point above ~150 °C because Liebig condenser with flowing water jacket (10-20 °C water, depending on the season) might burst. Funny enough, Keck clips have the very same limit.

I'll try to test it like you said and report the results. One of the problems is that I don't have a variable heating equipment. I resort to water and oil baths, and constantly monitoring the temperature, turning the hotplate on and off. I can never leave a reflux alone, which sometimes means hours of sitting down. I might try to modify my hotplate but I really don't like messing with electrical equipment.

watson.fawkes - 6-7-2012 at 07:27

Quote: Originally posted by Endimion17

Well, air condensers do serve a purpose. They're used for condensing liquids with a boiling point above ~150 °C because Liebig condenser with flowing water jacket (10-20 °C water, depending on the season) might burst.
[...]
I resort to water and oil baths, and constantly monitoring the temperature, turning the hotplate on and off. [...] I might try to modify my hotplate but I really don't like messing with electrical equipment.

In addition to air and water, there are other working fluids you can run through a condenser. The most obvious is automotive radiator fluid, called antifreeze but really "antiboil" to avoid vapor in the cooling loop, fully of ethylene and propylene glycol with higher boiling points. In general, you need to run such alternatives in a closed cycle, which means a radiator and a fluid pump. Such small radiators are available at the auto parts store as heater cores, small radiators used to transfer heat from the engine cooling loop to the passenger compartment. While this isn't a huge investment, it's not cheaper than seeing if air is an adequate working fluid for you.

Insofar as temperature regulation goes, there's a relatively easy electronics project to control heating mantles. It's a pulse-width modulation (PWM) for mains power. Heating doesn't require fast PWM; pulses on the order of seconds are just fine. And it will work for any heater. The circuit requires three semiconductors: a 555 timer chip, a ZC phototriac (zero crossing), and a power triac, you can make a PWM regulator for your mains power; total cost for these is less than 5 USD. Using a ZC phototriac driver gets rid of the bulk of line noise that you can hear in other triac circuits like lamp dimmers. The power triac can easily be rated at 15A or 20A, so it would work for any lab scale heater, or even the space heater in a garage. I've never seen this in a product, because most people need more sophisticated temperature control if they need any at all. And it doesn't regulate non-heater loads well. But it's just right for a lot of amateur science.

Texium - 12-7-2014 at 20:23

Sorry to bump an old thread, but I felt like I might have a some useful information to add regarding unconventional condenser setups.

Since I don't have a water pump, I just set up a ring stand supporting an upside down milk jug ( with the bottom cut open) with ice water in it that flows into the condenser, and then a little spigot that pours into a bucket on the other side. You simply pour off the water occasionally, and it will refill itself. If you use enough ice, you can even reuse the water. I usually keep a plastic pitcher full of water in the freezer so I always have a nice block of ice to use and it doesn't waste any water. It takes a little while to set up, but it's worked very well for me!

HgDinis25 - 6-4-2015 at 16:24

I'm sorry to bring up an old topic but I wanted to show you this:
https://hobbychemistry.wordpress.com/2015/04/03/types-of-con...

It is a general guide, made by me, discussing the most common types of condensers.

Zombie - 6-4-2015 at 17:36

Very nice article HgDinis25. I sort of focus on distillations, and I enjoyed the read.

Actually I am surprised there is not a "sticky" thread explaining most of the hardware available.

Thanks for sharing this.

Bert - 6-4-2015 at 19:06

FYI:

Ryobi 120 VAC pump. At Home Depot, less than $18.00. 40 gallons/hour at a moderate but useful pressure- Sold as a universal replacement pump for wet tile saws, but we might have other applications.

http://m.homedepot.com/p/Ryobi-Universal-Water-Pump-A113UWP/...

Amos - 7-4-2015 at 04:37

Quote: Originally posted by Bert

FYI:

Ryobi 120 VAC pump. At Home Depot, less than $18.00. 40 gallons/hour at a moderate but useful pressure- Sold as a universal replacement pump for wet tile saws, but we might have other applications.

http://m.homedepot.com/p/Ryobi-Universal-Water-Pump-A113UWP/...

Bert, have you ever used or known someone to use this product? And how is it powered?

[Edited on 4-7-2015 by Amos]

HgDinis25 - 7-4-2015 at 13:24

Quote: Originally posted by Zombie

Very nice article HgDinis25. I sort of focus on distillations, and I enjoyed the read.

Actually I am surprised there is not a "sticky" thread explaining most of the hardware available.

Thanks for sharing this.

Thanks and I'm glad you enjoyed it! The sticky thing would be very interesting. Covering all range of glassware and apparatus would be quite interesting.

Zombie - 7-4-2015 at 14:26

Quote: Originally posted by Amos

Quote: Originally posted by Bert

Bert, have you ever used or known someone to use this product? And how is it powered?

[Edited on 4-7-2015 by Amos]

Amos,

120VAC wall power in the US

aga - 7-4-2015 at 14:33

For the Paranoid out there, not all of the walls in the US are permanently charged up with 120VAC.

It's OK to touch US walls, or rest objects against them.

Best use rubber boots, gloves and a shower cap if you're not sure.

Zombie - 7-4-2015 at 14:45

Quote: Originally posted by aga

For the Paranoid out there, not all of the walls in the US are permanently charged up with 120VAC.

It's OK to touch US walls, or rest objects against them.

Best use rubber boots, gloves and a shower cap if you're not sure.

Mine are 120vac. I wired them myself

Rubber boots are a must...