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Picric-A
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Yes that reminds me of making picric acid, and that must be the reason you can start with SA... becuase it changegs to phenol during the reaction...
as for the benzene synthesis- that seems a very simple process to make benzene- the holy grail of aromatic compounds! :p thanks! 
Picric-A
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kclo4
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Your welcome, and good luck to you!
Well hey, if your interested in making benzene check out this; http://www.sciencemadness.org/member_publications/benzene_pr...
Also there is a lot of information about it on this forum.
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Ritter
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$12/pound on eBay, item # 270259620322. U.S.P. grade.
Ritter
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\"The production of too many useful things results in too many useless people.\"
Karl Marx
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kclo4
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Ritter is referring to Salicylic acid, not the many other chemicals that were mentioned.
http://cgi.ebay.com/Salicylic--Acid-U.S.P.-Grade-1-lb._W0QQi...
there is the link that goes with his description I believe.
+ $7.50 for shipping.
So, for a single pound of salicylic acid, its about $20.
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Ritter
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| Quote: | Originally posted by kclo4
Ritter is referring to Salicylic acid, not the many other chemicals that were mentioned.
http://cgi.ebay.com/Salicylic--Acid-U.S.P.-Grade-1-lb._W0QQi...
there is the link that goes with his description I believe.
+ $7.50 for shipping.
So, for a single pound of salicylic acid, its about $20. |
Given the cost of materials & your time, that is a cheap price to pay for buying something that's pretty basic rather than trying to make it.
Ritter
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\"The production of too many useful things results in too many useless people.\"
Karl Marx
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kclo4
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Well, not if you only need an ounce or so I would just make it personally.
Besides we are likely to already have some of the chemicals and glassware needed to make it.
I'd bet most of us here could make it with out buying any additional chemicals.
But I agree, if you need a large quantity of it, just buy it.
I think for what he is doing with it however you wouldn't need very much.
Plus, making chemicals is what its all about, right?
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Ritter
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| Quote: | Originally posted by kclo4
Plus, making chemicals is what its all about, right? |
At a certain point common sense (and your pocket book) will decide the question.
I'd rather have that extra USP sal acid in stock as a source of inspiration for future projects then spend a week boiling aspirin.
[Edited on 28-7-2008 by Ritter]
Ritter
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\"The production of too many useful things results in too many useless people.\"
Karl Marx
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pantone159
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I'm usually in the camp of buying reagents instead of making them, many more of my collection are purchased rather than synthesized, but there is
something appealing in making something interesting from a substance as ubiquitous as aspirin.
It does depend on how much you need, I doubt I would try and synthesize a kilo, but for a few tens of grams, why not make it?
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Picric-A
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I am with Kclo4 on this one, i try to make all most of my chemicals, the only ones i dont make are very basic chemicals like sulphuhric acid, sodium
sulphate anyhrous and solvents ect...
Yes i am sure you can buy salicylic acid fairly cheap, i can buy it 250g for £3.50 but this thread was about making it and some of its uses,
properties ect....
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S.C. Wack
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Walgreens aspirin is $4/162.5 g. ASA, which is 125 g. SA. So for $16, you get 500 g. SA instead of 454 g. for $17.50, if no one bids it up. Though
isolating all 500 g. in pure form will be a little more of a venture. The corresponding amounts of H2SO4 and NaOH for this are pretty cheap.
I must disagree about the
Horrible!
Chore!
of dissolving aspirin tablets, filtering, and boiling with NaOH for an hour or two in a teflon-coated saucepan on the stove. Maybe checking in once in
a while to add water.
And then adding acid.
Though some brands have some pretty goopy binder.
Apparently Ritter's time is better spent posting, instead of making salicylic acid.
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Ritter
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| Quote: | Originally posted by S.C. Wack
Walgreens aspirin is $4/162.5 g. ASA, which is 125 g. SA. So for $16, you get 500 g. SA instead of 454 g. for $17.50, if no one bids it up. Though
isolating all 500 g. in pure form will be a little more of a venture. The corresponding amounts of H2SO4 and NaOH for this are pretty cheap.
I must disagree about the
Horrible!
Chore!
of dissolving aspirin tablets, filtering, and boiling with NaOH for an hour or two in a teflon-coated saucepan on the stove. Maybe checking in once in
a while to add water.
And then adding acid.
Though some brands have some pretty goopy binder.
Apparently Ritter's time is better spent posting, instead of making salicylic acid. |
I would never waste time making what I could buy at a reasonable price. Since few amateur experimentalists have the necessary analytical equipment to
determine the purity of their produced materials, they may wind up defeating themselves by screwing up the downstream chemistry.
And Wack, please feel free to share your personal concerns via U2Us. You're starting to get needlessly repetitive.
[Edited on 29-7-2008 by Ritter]
Ritter
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\"The production of too many useful things results in too many useless people.\"
Karl Marx
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Picric-A
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I buy my asprin for 39p for a pack of 16. Personally this is an extremly cheap source of SA if i can master the hdyrolosis aspect of it.
I know this is silghtly paranoid but dont you think making things is etter than buying them because the more chems you buy the more the DEA take
notice of you?
i mean SA is probably not used to make drugs (not that i know of anyway) but just generally.
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Picric-A
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I buy my asprin for 39p for a pack of 16. Personally this is an extremly cheap source of SA if i can master the hdyrolosis aspect of it.
I know this is silghtly paranoid but dont you think making things is etter than buying them because the more chems you buy the more the DEA take
notice of you?
i mean SA is probably not used to make drugs (not that i know of anyway) but just generally.
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ScienceSquirrel
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The hydrolysis should be quite straight forward, this is for the methyl ester;
http://www2.truman.edu/~jobrien/Org%20I%20Labs/SalicylicAcid...
I would extract the tablets with sodium hydroxide, boil the solution and then acidify and recrystallise the acid.
If you get a good melting point then I would take it as being fairly pure.
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Picric-A
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yea that is the way i do it, how long should i boil it for?
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Ritter
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In real organic chemistry the U.S.P. grade is specified: http://www.orgsyn.org/orgsyn/pdfs/CV2P0341.pdf
Aspirin tablets contain binders & excipients that a crystallization will not guarantee to remove. For instance, what final wash solvent will you
use? Do you know the nature of these binders & excipients & therefore be able to successfully wash them out?
Ritter
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\"The production of too many useful things results in too many useless people.\"
Karl Marx
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ScienceSquirrel
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Most of the filler material in the tablet is insoluble in water so grinding up the tablets, extracting with warm sodium hydroxide solution and
filtering will remove all that.
After heating you will be left with a solution of di sodium salicylate and any water soluble glue.
Adding the sulphuric acid will precipitate the acid and leave the glue in solution.
Salicylic acid recrystallises easily from water, it is one of the great classics for undergraduate labs.
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Picric-A
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Yes i quite agree with you... some makes of asprin do contain lots of nast contaminents that you will want to remove but what i am saying is my
tablets are 400mg ASA and 50mg starch. plain and simple (not to mention cheap!)
my point is if i can buy tablets like these then other people must be able to buy them
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DJF90
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In the uk these usually come in small plastic tubs, about 15p for 20 tablets (used to buy paracetamol like this  ) and are available from most supermarkets
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Picric-A
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yep thats how i buy myn
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DJF90
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Ok... went into the shop today saw these little tubs, £0.13 (about $0.07?) for
20 300mg aspirin tablets in a plastic tub, only other ingredient is lactose (I assume it's used to bind the ASA crystals).
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Picric-A
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i saw the ones with lactose in. i think it was in wilkinsons.
i just thoght, even though they are cheaper they are probably more difficult to purify becuase i have no knolage on lactose's solubility ect...
I cant remember who said this but someone made as claim that paracetemol was cheaper than Asprin, i i have to disagree with that.
could someone tell me the properties of phenol? i reacted salicylic acid with conc sulphuric acid and got yellowish crystals, and i saw the msds of
phenol and it states collourless, hmmm....
Picric-A
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kclo4
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When you reacted the salicylic acid with sulfuric acid did you see carbon dioxide evolution?
The phenol would be in some sort of sulfuric acid salt. Also the color might be explained by some possible impurities in the sulfuric acid?
I think it needs to be neutralized to get the phenol alone.
You could then probably fractionally crystallize it from an aquas solution since its solubility seems to be pretty low at 8.3 g/100 ml at 20*C
according to Wikipedia.
Phenol forms a highly soluble salt with sodium hydroxide so perhaps use a carbonate.
Phenol doesn't react with carbonates, does it?
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DJF90
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No its too weak of an acid. Mixing with Na2CO3 should be fine 
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kclo4
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Sweet!
I wish I had a use for phenol, this thread is making me want to make it.
I wonder if chlorobenzene could be produced from phenol? That would make me very happy
--I wouldn't be to surprized if chlorobenzene was produced by refluxing anhydrous phenol while bubbling anhydrous Hydrogen chloride Into it? Along
with a lewis acid probably, such as Zinc chloride, which I would produce in situ from zinc metal.
Does anyone have an idea how to make chlorobenzene?
[Edited on 2-8-2008 by kclo4]
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