conducter
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Ketone distillation at atmospheric pressure
at the hive swim found this
Chromic
(Synaptic Self-Mutilator)
11-09-03 14:18
No 469860
MDP2P
"SWIC has seen MDP2P distilled without a vacuum at 283C (made from oxone and from peracetic routes)... but don't expect the teflon on the stir bar to
last for long, ensure everything is very insulated with glasswool (inc. the clamp), and your yields will be down about 10% on the recovery of the
ketone...
So by comparison, 200C is rather light heating... but again, make sure you use glass wool insulating everything, including the clamp. The stir bar
will be discolored... but not destroyed."
Is this really possible, swim is terrible and cannot for the life of him figure out what type of pump/aspirator to get and how to not explode his
distillation setup so he wants to try to distill the ketone at atmospheric pressure.
Would a chaser liquid be a good idea? to keep the mdp2p from charring in the flask to polymerized crap.
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Baphomet
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It would need to be very pure ketone.. and your 'chaser' had better be a high boiling point and pure as well.. otherwise polymerisation is bound to
occur. Why do it this way with all the insulation and ruined stirrers when you could use an aspirator? I've never seen a setup implode when using
aspiration btw.
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Magpie
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Vacuum is vacuum no matter the source. Whether or not your glassware implodes would seem to be a function of 1) glassware design, i.e., whether or
not it is designed for full vacuum, and 2) whether or not it has any defects, i.e., "stars," etc.
I would think it would be just good practice to bring up a vacuum slowly, thereby minimizing any additional stress due to dynamic conditions.
The single most important condition for a successful synthesis is good mixing - Nicodem
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Baphomet
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Sure glassware makes a difference but so does the vacuum source. An aspirator at 20 kPa is less powerful than a vaccum pump at 5 kPa
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Biginelli
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Quite a risky operation IMHO...
I'd use a vacuum distyllation without any question. Basing on theoretical nomogram the bp would be about 120 C if the pressure is , say, about 25
torr (casual water aspirator with all hydrawlic resistances inculded).
At 1 torr it should be about 80 C...
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MargaretThatcher
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| Quote: | Originally posted by Baphomet
Sure glassware makes a difference but so does the vacuum source. An aspirator at 20 kPa is less powerful than a vaccum pump at 5 kPa
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Let's stick to scientific terms. The vacuum pump has a pumping speed and limiting pressure. With a closed distillation set, the pumping speed is not
relevant - even a water-jet pump is capable of reaching its limiting pressure, the vapour pressure of water, with such a small volume.
The stress in the flask depends on the pressure differential, i.e. between atmospheric 100 kPa and the vapour pressure of the ketone at whatever the
distillation temperature is. Whether you are distilling with an aspirator at 1 kPa or a rotary pump at 0.5 kPa, the differential is still close to 100
kPa. The flask stress is the same, and the vacuum source will have no effect on whether the glass implodes, as Magpie says.
The reformative effect of punishment is a belief that dies hard, I think, because it is so satisfying to our sadistic impulses. - Bertrand Russell
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Ephoton
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Mood: trying to figure out why I need a dark room retreat when I live in a forest of wattle.
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steam my friends it works every time and all at just over 100C no polymerisation.
is that who I think it is or are you taken a nick like some one who took quantum.
if so whats goen on many rummors. if not thats realy wrong man especialy that one.
e3500 console login: root
bash-2.05#
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Organikum
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Substituted ketones dont steamdistill easily or at all.
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Ephoton
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Mood: trying to figure out why I need a dark room retreat when I live in a forest of wattle.
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md does  not too easy but hey it dont char just takes time. use a large sep as
your reciver with DCM in it. stir before droping solution out of funnel. having said that probably better to use a floating NP but never tried it.
e3500 console login: root
bash-2.05#
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conducter
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why have dcm in the receiver? was just gonna have a flask in an ice bath as receiver.
Also im wondering,i was inquiring about a Chapman Aspirator and was told it is totally satisfactory for mdp2p distillation.
the only worry is do ALL SINKS fit aspirators? or do you have to modify it, and if so how?
[Edited on 1-1-2007 by conducter]
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MargaretThatcher
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| Quote: | Originally posted by conducter
the only worry is do ALL SINKS fit aspirators? or do you have to modify it, and if so how?
[Edited on 1-1-2007 by conducter] |
You may be lucky in having an aspirator that will screw directly to the tap. More more likely not, in which case you will have to plumb something
together. You will also be flushing hundreds of gallons of drinking water down the drain every hour. Very wasteful. Better to rig up a closed circuit
system with pump. You can add ice to keep the temperature down and so improve performance.
The reformative effect of punishment is a belief that dies hard, I think, because it is so satisfying to our sadistic impulses. - Bertrand Russell
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conducter
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if one was in such a position where they did not have vacuum or aspirator avaiable... and just finished a wacker oxidation.
The ketone collected in DCM washed with saturated sodum bicarbonate solutions, saturated nacl solutions, and 5% naoh solution, then distiling off the
DCM to leave the impure ketone.
If this was used directly in an al/hg amalgam would the ratios go up from say 25g mdp2p to 30g of the impure mdp2p?
i believe that whatever ketone IS there will be reduced and then recovered as mdma while the impurities are broken down in the al/hg or simply washed
out in the workup. Can anyone verify that this could be done in a pinch?
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turd
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| Quote: | if one was in such a position where they did not have vacuum or aspirator avaiable... and just finished a wacker oxidation.
The ketone collected in DCM washed with saturated sodum bicarbonate solutions, saturated nacl solutions, and 5% naoh solution, then distiling off the
DCM to leave the impure ketone. |
Ok, my opinion on the matter: If you don't have the equipment then you don't make materials intended for human consumption. Poisoning yourself is
stupid, poisoning others makes you a big asshole. The fact that the material you want to make is commercially available makes it even worse. You don't
save money at the expense of other people's health. Period.
The wacker oxidation does not only give MDP2P, but also the propanal and probably other ketones. You have to remove them by
distillation (or chromatography).
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MargaretThatcher
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If you don't have a vacuum pump, make one. I think frogfot has a post here somewhere on how to make a water-jet pump. I made one with a 1" threaded
t-piece, some screw-in reducers, epoxy and some brass tubing from a model shop to see whether it would work, and by god it did! Just as well as a
commercial one.
[Edited on 2-1-2007 by MargaretThatcher]
[Edited on 2-1-2007 by MargaretThatcher]
The reformative effect of punishment is a belief that dies hard, I think, because it is so satisfying to our sadistic impulses. - Bertrand Russell
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conducter
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id like to see the writeup, is that picture of an aspirator? i have no problem getting an aspirator but just finding a sink that actually will connect
to it is hard. Some will say make the ghetto condenser in a bucket and hot tub pump to retun water to the bucket, but isnt that a little expensive?
not to mention that the part about the "baffle" confuses the hell out of me.
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Magpie
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What you need is a faucet that will connect to the aspirator. Most convenient is a faucet with a threaded spigot. From there you can get adaptors
that will connect you to the threads on your aspirator. If the faucet you presently have is not threaded then get a new one. You also want to be
sure that your sink is deep enough for the aspirator as installed.
The single most important condition for a successful synthesis is good mixing - Nicodem
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pantone159
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I found a 'faucet-to-garden hose' adaptor, as well as a 'garden hose-to-3/8 in ID' connector at my local brew supply store.
The bottom part of my faucet unscrews (I didn't realize this at first), then I can screw the adaptors on. I then connect 3/8 in ID tubing to these,
and this fits my aspirator.
Until I figured out that I can remove part of the normal faucet, I was lost.
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conducter
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finally, pantone, someone who knows the trouble im going through.
i have an aspirator let me describe to u...
The body is a nickel plated white metal and the baffle tube is manufactured from aluminum. The water inlet connection thread is a standard 3/8" NPT
taper.
Specifications:
Vacuum Inlet:
10 mm / .385"
Water Outlet:
10 mm / .385"
Length:
137 mm / 5 3/8"
Vacuum generated @ 30 psi
29.5" Hg
At a water pressure of 30 psi this aspirator will reduce atmospheric pressure by 29.5" Hg.
Standard pressure 29.92" Hg = 1 atm
- 29.50" Hg
Net pressure = 0.42" Hg = 0.014 atm
This is from the manufacturer, im not sure what it all means but is it good enough to distill high boiling ketones that would normally come over at
280C at atmospheric pressure?
I think i know what i have to do, find the sink which i will distilling next too, setup shop there. Then unscrew the faucet aerator, take it to the
hardware store and ask them for a thread adapter and give him the aspirator to hook up for me.
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gsd
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There is a bid thread running into 4 pages on homebrew aspirator
http://www.sciencemadness.org/talk/viewthread.php?tid=437#pi...
Tacho and several other members have made very useful contributions there. Why not refer to it ?
gsd
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conducter
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the aspirator isnt the problem, its figuring out if its strong enough and how to hook it up to the sink
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Magpie
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I think your aspirator is fine. Remember, 30"Hg is a perfect vacuum and you can't do better than that. Even if you had the most perfectly designed
aspirator money can buy you cannot get an absolute pressure less than the vapor pressure of your motive fluid, in your case water. In the winter my
aspirator gets me near 27"Hg. That is plenty to get the boiling point down to where you need it for most organics IMHO. For example, it will boil
water at room temperature.
Your plan to take the aereator and the aspirator to the hardware store is perfect. I believe my aspirator required 2 adaptors, hard piped, no tubing.
If you find the right guy at the hardware store (one that knows plumbing) he'll fix you up.
The single most important condition for a successful synthesis is good mixing - Nicodem
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conducter
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And always run the coldest water i can through the aspirator right? Also what kind of tubing would be best for this if vacuum tubing isnt able to be
ordred? I think i remember the guy saying something abut a plumbing store selling black vacuum tubing but im not sure.
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Magpie
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Yes, cold water as it has a lower vapor pressure. I ordered vacuum tubing out of a scientific supply house but any thick walled tubing that won't
collapse on you will do. If the hardware stores don't have it check an industrial supply place selling hose. Automotive parts places may have it
also.
[Edited on 4-1-2007 by Magpie]
The single most important condition for a successful synthesis is good mixing - Nicodem
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conducter
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How do i secure the vacuum hose to the distillation adapter and aspirator? Those little plastic ring ties? or tape or what
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MargaretThatcher
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Standard thick walled rubber vacuum tubing should push fit both ends OK without leaking. You'll have to improvise based on circumstances. Yes, you
want cold water for best limiting vacuum. If you build a recirculating system, you can freeze bags of water and float ice blocks to cool it all down.
Abolt on The Hive used to do that.
The reformative effect of punishment is a belief that dies hard, I think, because it is so satisfying to our sadistic impulses. - Bertrand Russell
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