Sciencemadness Discussion Board - Retort vs distiling flask (vertical neck w/y downward angled side arm) - differences?

Retort vs distiling flask (vertical neck w/y downward angled side arm) - differences?

RogueRose - 15-6-2018 at 02:12

So I am wondering if there is much difference between these two items. I was thinking of making an adapter that can fit onto a flask with 1-3 necks and then a vertical shaft that has a narrow downward arm coming off of it, like in the picture of the distilling flask, except that it would be 2 pieces.

retort.jpg - 7kB

LearnedAmateur - 15-6-2018 at 04:30

There are still heads/thermometer adapters that do the same thing, with three joints (one for a condenser or bubbler tube), but I haven’t come across one with just a narrow tube. But anyways, there isn’t really much different, the one on the right is just the modern version of a retort IMO.

hissingnoise - 15-6-2018 at 04:48

RR, I assume you know that neither set-up will distill more than a few cc. without connecting to a condenser...

Texium - 15-6-2018 at 05:11

Both are primative, inferior pieces of glassware compared to modern standard taper equipment.

wg48 - 15-6-2018 at 07:42

The item on the left is a reaction flask and integral air condenser. Typically in the old days used for distilling high temperature boiling or corrosive liquids such as sulphuric acid, nitric acid and mercury because it’s all glass.

The item on the right is a reaction flask with integral take off side arm. Typically in the old days a bung with a thermometer would be inserted in to the top to monitor the temperature of the distillate or the contents of the flask depending on the position of the thermometer bulb. The side arm would be attached to a condenser with an other bung.

I am gobsmacked you have not seen pics similar to the ones below in old books.

retort3.jpg - 6kB

[Edited on 15-6-2018 by wg48]

zed - 19-6-2018 at 18:50

I used to own a decent sized side armed distilling flask. Perhaps a 2000-3000 ml unit.

In days of yore, such items were dirt cheap. Not so nowadays. You can still buy 'em, but they are spendy. To my recollection, within the last year or so, one of our members obtained one constructed of Quartz..... For the purpose of distilling Sulfuric Acid, etc..

On occasion, I heated mine with a Bunson Burner, and thereby steam-distilled benzene/water out of a reaction mix.

I don't know that I would have attempted that, with regular jointed glassware.

Probably not.

Well sealed, it seemed pretty safe for distilling flammable solvents. Though of course, not ether.

DrP - 20-6-2018 at 00:14

For bumpy distillations or high temp ones at reduced pressure where the impurities are of close BP to your target product you can put a fractional column in there too. That way if it does bump then it goes up and down the column and not over to your pure product. You can get more control of it with a column in there too imo.

SWIM - 20-6-2018 at 07:40

Quote: Originally posted by hissingnoise

RR, I assume you know that neither set-up will distill more than a few cc. without connecting to a condenser...

If you've got two of them, you put the thin output tube of the one being heated through a cork in the top of the other one (all the way down to the bulb)and cool it with an air blast, or even water poured over the bulb.

This is very old school, but works if the Boiling point isn't too low.
(Be sure to trim your corks and treat them with collodion if you're trying a vacuum distillation this way, and you might want to grow a handlebar moustache to complete the whole 1890s chemist image)

weilawei - 20-6-2018 at 08:02

Are we sharing terrible improvised distillation equipment now? My favorite was always the pyrex bowl inside a stew pot with its lid upside down with ice on top. Put your thing to be distilled into the stew pot, and let it condense into the bowl. Everyone's got distillation apparatus at home!

This is spectacularly quick and dirty, but does work in practice. Not that I ever want to work that way again...

SWIM - 20-6-2018 at 09:35

Nothing improvised about the double flask thing.

It was a common old practice, and illustrations can be found of this setup pretty easily.

If you're curious, try Fieser and Fieser's lab manual, Organic Experiments.

zed - 20-6-2018 at 12:14

Yup. If I had a couple of 'em now, I'm sure I would find uses for them.

But, as stated before, those sidearm distilling flasks, are no longer easy to locate, and even more troubling..... They are kind of expensive.

Though.... I do know a friendly glassblower. Hmmmm.

hissingnoise - 21-6-2018 at 06:48

Quote: Originally posted by SWIM

An air blast is a piss-poor alternative to circulating water and cooling the receiver with water needs water constantly running onto it from the tap...

coppercone - 21-6-2018 at 08:27

Nah these aee not inferior their just specialized. If you want to torture glassware say for distillation of sulfuric acid you cant beat an air cooled retort that is one piece of glass.. Nothing esle stands up well to high temp distillation because you get seized joints and shit

For h2so4 distillation i would like a pear shaped retort i can do direct flame heating on for the first run. I got super paranoid about glassware cracking when i did it, i used a hempel column as a condesner and a j joint but everything seized up with vacuum grease and i was banging on it with a rubber hammer and a gas torch to seperate it.

I think i put a fan to cool my air condesner but with a boiling point of 337c you probobly want to use a air heater to cool it to maintain some kind of reasonable gradient of temperature. I was paranoid about glass cracking. It should be vacuum distilled but purifying a gallon of drain cleaner is industrial chemistry imo at least for the first pass. I like using a blowtorch with the air holes mostly clogged to make a gentle flame that waves around the glass

[Edited on 21-6-2018 by coppercone]

[Edited on 21-6-2018 by coppercone]

SWIM - 21-6-2018 at 08:29

Air blasts work fine for what they are appropriate for.

Water, however, is a piss poor cooling medium for anything where the water would make for excessive thermal stress on the condenser.

As for cooling the receiver with water, yes exactly like the diagrams I mentioned above.

Glad you were able to interpret that diagram properly, but I would have assumed you were able to do so anyway.

After all, it is just a basic lab manual...

And just out of curiosity, have you figured out yet that your condenser requires water as well?

hissingnoise - 21-6-2018 at 09:19

Quote: Originally posted by coppercone

For h2so4 distillation i would like a pear shaped retort i can do direct flame heating on for the first run. I got super paranoid about glassware cracking when i did it, i used a hempel column as a condesner and a j joint but everything seized up with vacuum grease and i was banging on it with a rubber hammer and a gas torch to seperate it.

The problem with distilling H₂SO₄ is that if the flask cools a tad too quickly from 339° the stresses introduced will likely cause it to fail during subsequent runs ─ If I were to distill sulphuric acid I'd want some way of annealing the glass and to prevent joints seizing I'd lubricate with the conc. acid...

hissingnoise - 21-6-2018 at 09:35

Quote: Originally posted by SWIM

And just out of curiosity, have you figured out yet that your condenser requires water as well?

Just out of curiosity; are you mentally retarded or what ─ if that's not a leading question?

coppercone - 21-6-2018 at 10:42

Quote: Originally posted by hissingnoise

Quote: Originally posted by coppercone

yes which is why I said you should aim a heat blower at it for cooling if you want to repeat my work with less danger

hissingnoise - 21-6-2018 at 11:33

Of course you should use an air-condenser for distilling HB fluids, but in this case, blasting it with air is neither necessary nor desirable...

The only 'danger' is a RBF that's been compromised, obviously...

SWIM - 22-6-2018 at 09:55

Quote: Originally posted by hissingnoise

Quote: Originally posted by SWIM

And just out of curiosity, have you figured out yet that your condenser requires water as well?

Just out of curiosity; are you mentally retarded or what ─ if that's not a leading question?

My, how very, very sad.

Throwing a hissy-fit is a poor way to react when you can't understand the question.

I realize puberty can be a trying time, and these new feelings you're having can be very confusing, but taking your frustrations out on the world around you is not only inappropriate, but a rather tired cliche as well.

You may appreciate this further when you mature somewhat.

Texium - 22-6-2018 at 10:55

Quote: Originally posted by hissingnoise

Quote: Originally posted by SWIM

And just out of curiosity, have you figured out yet that your condenser requires water as well?

Just out of curiosity; are you mentally retarded or what ─ if that's not a leading question?

Please refrain from ad hominem. We're better than this.

hissingnoise - 22-6-2018 at 12:08

Quote: Originally posted by SWIM

I realize puberty can be a trying time, and these new feelings you're having can be very confusing, but taking your frustrations out on the world around you is not only inappropriate, but a rather tired cliche as well.

Oh dearie me! Little closet-boy's got his panties twisted knotwise...

hissingnoise - 22-6-2018 at 12:14

You know me, Texium ─ I can tolerate most anything except wilful ignorance...

JJay - 22-6-2018 at 12:56

I think you could do short path distillation at temperatures below the boiling point of the mixture with a retort. Distillation flasks have more options than retorts, but generally speaking, you probably don't want to buy either for chemistry use unless you can get an exceptionally good deal or have a specific application. (For example, I have a standard taper quartz distillation flask for distilling sulfuric acid.)

ave369 - 22-6-2018 at 13:17

I use both retorts and distillation flasks. The former I use mostly for nitric acid, and also as the first stage condenser for sulfuric acid (injecting hot, not precooled H2SO4 vapor into a water-cooled condenser = bye bye condenser).

j_sum1 - 22-6-2018 at 15:56

Quote: Originally posted by hissingnoise

Just out of curiosity; are you mentally retarded or what ─ if that's not a leading question?

Quote: Originally posted by SWIM

Quote: Originally posted by hissingnoise

Oh dearie me! Little closet-boy's got his panties twisted knotwise...

[moderator hat is on]
SWIM and hissingnoise - cut it out!
We just don't need this. Nor do we need you justifying yourself, hissingnoise.
[/mod hat]

hissingnoise - 23-6-2018 at 11:28

Quote: Originally posted by j_sum1

Nor do we need you justifying yourself, hissingnoise.

You're right as usual, j_sum1!

Normally, I don't even engage these shitforbrains K3WLs in conversation and that "SWIM" moniker should have put me right off.

But I'm sober today, though still, er, somewhat impaired...

Mea culpa.

SWIM - 23-6-2018 at 13:34

Quote: Originally posted by hissingnoise

Quote: Originally posted by j_sum1

Nor do we need you justifying yourself, hissingnoise.

My, how very sad.

hissingnoise - 24-6-2018 at 01:04

Touché!