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aga
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aga Does Decarboxylation
Appologies for arriving here, however it was inevitable, a bit like the common cold getting to you eventually.
Today 25g of salicylic acid had some fire under it in a distillation rig, following Nile Red's video to produce Phenol :-
https://www.youtube.com/watch?v=A0e0BDEE4Ic
Not having a 'short distillation setup' (which looks pointless) i just did this :-
It worked OK until the boiling flask got low on juice, and no more distillate came over, so i swapped from 250ml to a 50ml boiling flask and 25ml
receiver :-
This didn't work either as the condensation front was having a hard time getting up to the stillhead, so i added some insulation :-
... which works fine !
Tomorrow vac distilling a couple of times to get a few g of Phenol.
Oh the Joy and smell of burnt plastic !
[Edited on 14-9-2015 by aga]
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Little_Ghost_again
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In the first pic isnt the thermometer a bit low?
Dont ask me, I only know enough to be dangerous
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aga
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It would be for Scotland, yes, then i remembered where i was.
[Edited on 14-9-2015 by aga]
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The Volatile Chemist
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HAHAHA  Aga... just in case you actually didn't get what he meant, it's lower
than the branch to your 'condenser', so the crossover vapor temp. wouldn't be accurate. Not that it matters too much.
Awesome synth, by the way. If I ever pick up some Salicylic acid, I'll try it. Where'd you get yours?
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UC235
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Uh, you do know that Nile Red's video is from my writeup in prepub, right? That last bit of liquid might not have been phenol at all, but phenyl
salicylate or xanthone. Did the temperature rise a lot when it passed over?
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aga
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Yes, i did know, which is why it's corrected later. I was concerned that condensate would block the thinner nozzle of the vac adapter (which i thought
was why the short path condenser was full of hot water in the utoob vid) and didn't notice until later.
Ebay !
Quote: Originally posted by UC235  | | Uh, you do know that Nile Red's video is from my writeup in prepub, right? That last bit of liquid might not have been phenol at all, but phenyl
salicylate or xanthone. Did the temperature rise a lot when it passed over? |
I did not know that UC235. I'll have a good read in pre-pub when i've gotten to the point that i can understand some of the writings.
Seems like an excellent & simple synthesis for beginners.
Yes, the temperature shot up to 210 C briefly then fell to just under 100, at which point the distillation was stopped.
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aga
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First ever vac distillation
Sure goes fast !
Certainly won't forget to put boiling chips in the pot again.
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Oscilllator
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Sure. Just like I'll never leave the stopcock open on my sep funnel again...
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aga
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Starting with 25g salicylic acid the result after third distillation was a paltry 4.7g of (presumably) phenol.
Seeing as it forms crystals, would not a simple recrystallisation be easier for purifying the stuff after the salicylic acid is decarboylated to
phenol ?
Oh, for a Beginners experiment this is a terrible one.
Phenol is rather poisonous, carcinogentic, crosses the skin barrier easily and burns the skin.
http://www.atsdr.cdc.gov/mmg/mmg.asp?id=144&tid=27
Naturally i got a drop of the stuff on my leg, and it stings like crazy !
15 mins washing in the shower was recommended, so i did that.
Seems i should have some PEG knocking about in case of skin splashes (should have done that synthesis first i guess).
Symptoms of Phenol induced CNS damage include "nausea ... dizziness ... loss of consciousness, coma".
Thankfully this all home territory.
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The Volatile Chemist
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That's too bad. Have you tested it to see if it is phenol?
It seemed like an easy process... I know the feeling. I thought making some CaCl2 from my reagents would be easy. Nope. Too many fumes, too
many impurities in the HCl (The solution was bright YELLOW...) and the Plaster of Paris (I was going to filter out the Calcium Sulfate).
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PHILOU Zrealone
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Phenol is readily sublimable while salicylic acid is not...no need for distillation and consequent losses!
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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aga
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CaCl2 is relatively easy with the right starting reagents.
Get some white sea shells from the beach (best) or some limestone (more impurities) and dissolve it in HCl.
Avoid chalk. Tends to be Calcium Sulphate and other random crap.
When i did the Limestone version, it stank of sulphates.
CaCl2 will never dry in air - it deliquesces.
I just dumped the solution/paste straight onto the hotplate.
That was the easist way to near anhydrous.
For proper anhydrous you'd have to melt it in a stream of dry argon or something.
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The Volatile Chemist
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"Strait onto the hotplate"??? :/ Sheesh...
I'll try that. (not onto the hotplate though, my hotplate's crappy as it is...)
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IrC
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| Quote: Originally posted by aga | | Seems i should have some PEG knocking about in case of skin splashes (should have done that synthesis first i guess). |
I searched to no avail, why I wish such terms were always defined at least once in any thread. All I got was:
PEG or Peg may refer to:
Devices
Clothes peg, a fastener used to hang up clothes for drying
Tent peg, a spike driven into the ground for holding a tent to the ground
Tuning peg, used to hold a string in the pegbox of a stringed instrument
Piton, a metal spike that is driven into rock to aid climbing
PEG tube, a medical device, that is, a percutaneous endoscopic gastrostomy tube
Foot peg, a place to put one's foot on a vehicle such as a motorcycle
Science and computing
Peg (unit), a measure used in preparing alcohol, from 1 to 2 fluid ounces
Pegasus (constellation), a constellation named after Pegasus
Percutaneous endoscopic gastrostomy, a medical procedure
Polyethylene glycol, a chemical polymer
Parsing expression grammar, a type of formal grammar used in mathematics and computer science
PCI Express Graphics (PEG), a port for computer graphics cards
Recreation
Peg, a rule in the game of backyard cricket
Peg (fishing), an area set aside for an angler
Peg solitaire, a board game for one player
PEG: Pinnacle Entertainment Group, a game company
People
Peg, an abbreviation of Peggy (given name), itself a diminutive of the name Margaret.
Transportation
PEG, the National Rail code for Pegswood railway station
PEG, the IATA airport code for San Egidio Airport
Other uses
PEG or PEGA channels, public, educational, and government access cable TV channels in the United States
Peg (currency), or Fixed exchange-rate system, a system to value currencies
PEG ratio, price/earnings to growth ratio, a stock price analysis tool
"Peg" (song), a song by Steely Dan
Mnemonic peg system, a memory aid
Program for the Exceptionally Gifted, a program at Mary Baldwin College
Winnipeg, Manitoba, Canada, nicknamed "The Peg"
Treenails used in woodworking joints such as timber framing, holds joints together, particularly the mortise and tenon joint. Also called a peg,
pin or dowel.
Somehow I get the feeling none of this wiki page covers what you meant except possibly 'Polyethylene glycol, a chemical polymer'. Even so I'm not sure
what use this would be for Phenol skin poisoning. A common wire enamel stripper called Strip-X I used daily years ago was IIRC nearly pure Phenol and
I had many problems from it, not the least of which were blinding headaches that made one wish a safe would land on it to put an end to the suffering.
Damn near no information of the danger of working with Phenol was provided with the bottle so putting it on a towel and cavalierly running a wire
through it for stripping was commonly done. Later study online of the danger of working with Phenol reminded me of the old 1800's books I read where
untrained people toyed with HF, Ammonium Bifluoride, HCN and many other chemicals at home.
"Science is the belief in the ignorance of the experts" Richard Feynman
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aga
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As per the reference given in my 5th post in this topic, PEG refers to polyethylene glycol.
I assume you decided to Type a lot of crap rather than bother to read the rather important reference to the medical handling procedures where phenol
poisoning is suspected.
Please, do not repeat this synthesis right now.
You might not survive, and despite this particular gigantic inbicilliosity, you're one of the good guys, and i'd rather that you live, and do some
amazing chemistry one day.
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IrC
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I didn't type a lot of crap I copied and pasted it. I also did not read the very long link you posted as I have no need to do this experiment and
decades ago learned the value of not accumulating chemicals I do not have an actual use for. Too many troublesome experiences in years past trying to
safely dispose of hazardous chemicals I collected but never really needed taught me that. My complaint was merely directed towards using an
abbreviation in a thread without at least defining it once. If I ever do any more amazing things in science this late in life I doubt it will involve
chemistry. Most likely it will revolve around some combination of mega-volts, mega-amps, plasma, radiation and/or electro-gravitic UFO's. What
chemistry I do now is related to such endeavors as it is required.
"Science is the belief in the ignorance of the experts" Richard Feynman
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aga
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Very wise words IrC.
I'll dispose of ~50ml of chloroform today seeing as it has sat in a drawer for about a year.
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aga
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Chloroform all safely wafted away on the wind.
Now for the Phenol. Anyone any ideas of what to do to render it safe for disposal ?
Googling has returned hundreds of 'label it and put in the chem waste bin' which seems Lame considering that many of those papers were from academic
labs.
Also, what was the brown tarry goo left over in the boiling flask ?
Has a post been deleted ? I feel sure there was some mention of using a 0.2mm orifice made from a glass pipe instead of boiling chips in vac
distillations.
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PHILOU Zrealone
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Bis repetita:
Sublimation of warmed reaction mixture on a cold glass surface will deposit only the sublimated phenol and not the salicylic or biphenyl or tarry
material.
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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aga
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Noted the first time.
Quam ob causam dixisti repetere? Ego experiri.
After that, how to destroy it, as in render safe for disposal ?
NaOH ?
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IrC
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| Quote: Originally posted by aga | Noted the first time.
Quam ob causam dixisti repetere? Ego experiri.
After that, how to destroy it, as in render safe for disposal ?
NaOH ? |
https://en.wikipedia.org/wiki/Phenol
"Phenol is easily neutralized by sodium hydroxide forming sodium phenate or phenolate, but it being weaker than carbonic acid cannot be neutralized by
sodium bicarbonate or sodium carbonate to liberate carbon dioxide
C6H5OH + NaOH → C6H5ONa + H2O"
"Science is the belief in the ignorance of the experts" Richard Feynman
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aga
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Couldn't face the cleanup again, so just destroyed the phenol instead.
The IrC approach to making & keeping nasty stuff you don't immediately need is really very sensible.
Also saves space.
I'll remember the sublimation tip PHILOU Z, thanks.
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The Volatile Chemist
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The brown tarry goo was: tar.
In o-chem, from what little I've done and seen, tar forms because of decomposition when working at high heat all the time. One synth on versuchschemie
for making angelase from fructose and HCl made what looked to be 100 grams of tar from the sugar's decomposition. I guess it's just commonlace, and
why distillation is necessary a lot of the time.
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HeYBrO
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could of made phenolphthalein instead of wasting it...
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aga
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Waiting on some DCM to arrive to try to make pthalic anhydride from some gloves.
Will make the required phenol after i've got the other reagents for phenolpthalein.
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