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Mailinmypocket
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Phenol from salicylic acid in German but Google Translate does a fairly nice job of converting it to English.
Attachment: phenol.pdf (18kB)
This file has been downloaded 1347 times
CAUTION: Phenol is rapidly absorbed through skin, and from the stomach and lungs. Systemic toxicity can result from ingestion of solutions, or
from inhalation or cutaneous absorption of solutions or vapor. This is characterized by an initial excitatory phase, rapidly progressing to
fulminating CNS depression with coma. Potential symptoms of acute overexposure are steatorous breathing, mucous rales, froth at mouth and nose, frank
pulmonary edema; cyanosis; tremor, convulsions, twitching; death due to respiratory failure. Characteristic odor of phenol on breath. Ingestion may
cause burning of mouth and throat; white necrotic lesions in mouth, esophagus and stomach; abdominal pain. Direct contact may cause irritation of
eyes, nose and throat; skin burns; dermatitis; ochronosis. Chronic exposure may result in vomiting, difficulty swallowing, excess salivation,
diarrhea, anorexia, weight loss; headache, fainting, vertigo, mental disturbances; muscle aches and pain, weakness; damage to liver and kidney, dark
urine. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 248; Clinical Toxicology of Commercial Products, R. E. Gosselin et al.,
Eds. (Williams & Wilkins, Baltimore, 5th ed., 1984) Section III, p344-348; Patty's Industrial Hygiene and Toxicology vol. 2B, G. D. Clayton, F. E.
Clayton, Eds. (Wiley-Interscience, New York, 4th ed., 1994) p 1567-1584.
[Edited on 2-10-2013 by Mailinmypocket]
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DJF90
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@bfesser: Don't be so lazy. I appreciate german may not be your first (or second) language but I don't speak it either and I managed. Theres some
interesting stuff on there so its worth a browse and you'll pick up phrases etc as you go. Either that or you can use google translate like most other
non-german speaking visitors
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bfesser
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Heh. I was under the impression that you were the one being lazy. I can read German fairly easily, and could find the link myself, but that's not
really the point. The point is that you should have provided the link in the first place, rather than sending everyone else on an errand to see what
you're referring to. Personally, few things annoy me more than when members mention the existence of a reference, then fail to provide it.
Since you, apparently, can't be arsed... here's the link [again, apparently]:
http://www.versuchschemie.de/ptopic,287006.html <img src="../scipics/_ext.png" />
[edit] Just saw Mailinmypocket's post...oh well.
[Edited on 2.10.13 by bfesser]
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DJF90
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Ha thats a good one. I don't have time to go searching around for stuff on the behalf of others unless I have the page open in another window. It is
not being lazy, I told you where the reference was and its up to you to go and get it, just like any other literature citation. Sure, "go see VC" is
pretty vague but anyone with half decent searching skills would find the page in question with minimal effort.
And like I said, its worth looking for as theres a bumload of other decent experiments over there in the same subforum, most with decent pictures.
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Fantasma4500
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i recall benzoic acid can be heated and condensed into phenol, chemcamtv told me he did it before, if im not entirely wrong i recall he used copper
salts as catalyst for it..
benzoic acid is relatively easy to make and even easier to seperate..
sodium benzoate shouldnt be too hard to get a hold of, if this has HCl added while in solution benzoic acid will ppt. out as a white mass
its easily dried, but when its a dry powder you might want to pour it into whatever container youre gonna store it in, it stings alot, and is most
likely quite toxic to inhale
basically..
sodium benzoate, add HCl, filter and dry out, heat and condense
im very very sure it was benzoic acid used for this, i could be wrong, but im quite sure it was..
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bfesser
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I could be mistaken (and likely am), but I was under the impression that copper(II) benzoate will decarboxylate to benzene under such conditions. I
think you may be confusing benzoic and salicylic acids.
[edit] <a href="viewthread.php?tid=325">Benzene synthesis</a>
[Edited on 3.10.13 by bfesser]
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mr.crow
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Heating a flask with a torch seems kind of crude so I searched for a better method. I found an interesting Patent.
It uses molten benzoic acid as a solvent plus a benzoate salt as a catalyst.
A good experiment would be to mix benzoic acid, salicylic acid, and nickel carbonate in a distilling flask and heating with a mantle to 200C. The
salicylic acid can also be constantly replenished.
Double, double toil and trouble; Fire burn, and caldron bubble
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MichiganMadScientist
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So here's the deal. I completed the process suggested by the OP. Everything went very smoothly......and I feel I got a very good yield of the crude
salicylic acid as a result of hydrolysis of aspirin. I then took the crude salicylic acid, and heated it in a beaker which was being covered by a
watch glass. The white crude melted at a relatively low temp (my hotplate was only set on 2/9), and very nice large crystals then condensed near the
top of the beaker.
My question is: is this phenol? Or did I just collect sublimmed salicylic acid crystals? The crystals don't have a super strong odor, and I'm still
trying to think of other simple analytic tests I can perform. Any suggestions? Thanks.
[Edited on 4-10-2013 by MichiganMadScientist]
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confused
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if you have some phalic anhydride handy, you could convert it to phenolphalein and look for a colour change under acidic or basic conditions.
http://www.youtube.com/watch?v=lBIxBJMZD9Y
and it should react with sodium bicarbonate to form carbon dioxide gas
10 C6H5OH + 10 NaHCO3 = 10 C5H5Na + H20 + 20 CO2
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MichiganMadScientist
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I have no phalic anhydride available, so that test is a no go. I'll try the sodium bicarb test though....thanks for that. 
I just tried comparing the solubility of my white crude (salicylic acid) with my mystery crystals. The mystery crystals seem to dissolve appreciably
better in water than my crude salicylic acid......and this seems consistent with the fact that Phenol is significantly more water soluble than
salicylic acid....
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Magpie
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Quote: Originally posted by MichiganMadScientist  |
My question is: is this phenol? Or did I just collect sublimmed salicylic acid crystals? The crystals don't have a super strong odor, and I'm still
trying to think of other simple analytic tests I can perform. Any suggestions? Thanks.
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Phenol has a strong and distinctive smell. But to answer your question there is a color test with FeCl3:
http://en.wikipedia.org/wiki/Ferric_chloride_test
The single most important condition for a successful synthesis is good mixing - Nicodem
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MichiganMadScientist
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Well, my mystery crystals don't have a very distinctive smell, so that's not encouraging. Also, I tried sodium bicarb test, and both my white crude
and my mystery crystals produced outgassing upon the addition of sodium bicarb in the presence of water.....
And regrettably, I don't have any ferric chloride sitting around, so that test won't be possible for me...
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confused
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you can get ferric chloride as an etchent for printed circuit boards
also, you can make phthalic anhydride, but its kind of impractical if you're just making some to test for phenol
[Edited on 4-10-2013 by confused]
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DJF90
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Sodium bicarbonate will not react with phenol, it is not a strong enough base. The fact your sublimate reacts with sodium bicarbonate indicates it is
the acid, although there may be some phenol present. Ferric chloride test for phenols probably won't distinguish the two either as salicylic acid is
also a phenol! Though you may have some luck if different coloured complexes are produced for the two compounds.
The easiest analytical work you could do is a melting point determination. That should give you a pretty good indication.
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hames
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hi guys,I've had about 3l of dirty 88% phenol solution lying around for a while and wish to purify it,its from the bottom of an old corroded 205l drum
I found at work so its almost black. It absolutely reaks of phenol so I'm guessing its still quite potent,Im going to try a liquid/liquid extraction,I
have a few solvents I can try with such as dichloromethane,ethyl acetate,methyl isobutyl ketone,methyl amyl ketone,D-40-D80 solvents,ethylene glycol
monobutyl ether the ethylene glycol monomethyl ether,ethylene glycol monomethyl acetate and diethyl ether plus a few more hardware store types.I want
to avoid distilling but if I have to I will if so what should I use to neutralise phenol vapours coming from the vacuum takeoff.
any general tips would be appreciated by those in the know.
jim
[Edited on 4-10-2013 by hames]
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macckone
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| Quote: Originally posted by DJF90 | @Macckone: Where did you get that data from? Its way off according to Sigma:
HCl (gas) LD50 Oral (Rabbit) 900 mg/kg
Phenol LD50 Oral (Rat) 410-650 mg/kg, LD50 Dermal (Rabbit) 630 mg/kg
Phenol is pretty nasty stuff. Its hepatotoxic (liver) and sufficiently volatile to cause concern. I've seen a bottle where half the contents were in
the upper part of the bottle due to sublimation.
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http://kni.caltech.edu/facilities/msds/HCl.pdf for LD50 man oral
I would trust actual LD50 oral man for liquid vs LD50 oral rabbit of gas for a practical. I am guessing they intubated a rabbit and pumped the gas
straight into the rabbits stomach where HCl is less toxic. While the LD50 man was probably from medical records of people actually swallowing it and
destroying their esophagus.
My figures for Phenol were more toxic than yours so not really in question there. But the reality is that phenol is not that toxic. A 100kg man
(using my weight) would have to ingest 25g of the stuff to have a 50/50 chance of dying. I wouldn't do that but certainly quantities up to a gram are
not going to kill a healthy adult although it may make you very very sick. People have swallowed a whole bottle of Chloraseptic (2.4g of phenol)
without dying although I am sure there was lots of vomiting and an emergency room visit and maybe even an extended hospital stay.
For comparison purposes phenol is an order of magnitude more toxic than sodium chloride while sodium cyanide is two orders of magnitude more toxic
than phenol. And tantalum chloride is an order of magnitude more toxic than phenol. So although it is toxic, it is not what one would think of as
deadly toxic, nor is it a cumulative poison like tantalum or other heavy metals.
I really wish LD1 was commonly published for compounds because that is a base minimum of what can kill a person vs 50/50 chance of killing a person.
Keeping in mind I don't advocate skipping safety precautions but the common perception of phenol as 'deadly toxic' is not really accurate. It is
certainly toxic and it isn't a good idea to get it on your skin or breath the vapors, a small amount of exposure should not send you screaming to the
hospital.
ORM-D is a very stringent definition of toxic and phenol just barely makes it using my figures and Using your figures it doesn't make it for oral
ingestion.
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Magpie
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Why all the fuss about phenol toxicity - you are not planning on sticking your snoot in it are you?
In the old days phenol was commonly called carbolic acid and was widely used as a disinfectant in hospitals.
The single most important condition for a successful synthesis is good mixing - Nicodem
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macckone
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My point exactly, the stuff isn't good to ingest or get on your skin but taking reasonable precautions it is unlikely to kill you.
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testimento
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Has anyone researched this method:
http://www.greener-industry.org.uk/pages/phenol/8PhenolProdM...
Essentially benzoic acid can be made in liquid phase catalytic oxidation of toluene.
After that, benzoic acid would be catalytically decarboxylated at 240-249C(BP) to phenol and carbon dioxide over copper catalyst. I'm not perfectly
sure is this at gas phase or liquid phase, but if it were the latter, it'd simply consist by mixing catalytic copper with benzoic acid and heating it
up to that.
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blogfast25
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| Quote: Originally posted by Magpie | Why all the fuss about phenol toxicity - you are not planning on sticking your snoot in it are you?
In the old days phenol was commonly called carbolic acid and was widely used as a disinfectant in hospitals. |
Thank G-d for a bit of common sense!
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DraconicAcid
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| Quote: Originally posted by testimento | | After that, benzoic acid would be catalytically decarboxylated at 240-249C(BP) to phenol and carbon dioxide over copper catalyst.
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Er, you mean C6H5CO2H -> C6H5OH + CO2? There's an oxygen appearing from nowhere,
there...
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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testimento
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Sorry, forgot the N2O. 
So the process would essentially go like this on a tabletop:
In first, one makes a distillation apparatus with dropper funnel filled with conc. ammonium nitrate solution. This drops onto the reactor heated
strongly to instantly vaporize the water and cause the AN to turn into N2O. AN would cause mass detonation risk if heated in bulk and the gas
generation speed would be very difficult to control. Gas and water steam are led through condenser and water is accumulated into the receiver. The N2O
is led with pipe out of the receiver and it goes through desiccant trap to remove moisture, and is then lead through pipe. To this pipe is connected
another reactor fitted with dropper funnel filled with anhydrous toluene. Toluene is dropped into the highly heated reactor to vaporize it, and both
gases mix in the tubing and are then led into the main reactor. Metal tube reactor filled with ZnO impregnated silica gel is heated up to 450C, in
where phenol is supposed to form in 35% yield at 99% selectivity. The outcome is lead into condenser column and is accumulated into flask and can be
purified by fractional distillation to yield high purity phenol.
Should be a lot cheaper method than to mess up with salicylic acid. 
[Edited on 14-2-2014 by testimento]
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