darkflame89 - 16-4-2004 at 02:54
I have read from frogfot's webpage that oxalic acid can be made by oxdidsing sucrose with nitric acid. Is there any possible way to do that
without nitric acid?
And i need to synthesise phenols too. I have read about the cumene process but I do not have the precursors. Lets see, i have only a few compounds
that are benzene related: Benzyl benzoate, and napthalene(moth balls). Can these be somehow used??
I am actually want to make the phenyloxalate ester but i need this 2 compounds to do that.
Marvin - 16-4-2004 at 04:49
Still after the lightstick compounds I see.
You can make oxalic acid without nitric acid. One way is to heat sawdust with a mixture of solid NaOH and KOH, the mass produces flammble gas during
heating and takes up oxygen, when finished, it is dissolved in water, CaCl2 is added, the precipitated calcium oxalate is filtered off, and digested
with dilute sulphuric acid and the filtrate of that is evaporated to crystalise fairly pure oxalic acid.
The details I omit for breviaty because you might be able to find oxalic acid for sale. Try looking for ferric chloride stain remover, somewhere that
sells equipment and chemicals for electronics/making circuit boards.
You will need PCl5 for converting this into oxalyl chloride, though you may be able to make do with sulphur and chlorine if you can find a way to
seperate the products. This reaction is going to be very nasty to do. Fume hood only and the same goes for reactions with the products.
For the phenol one way would be to start with either asprin, or methyl salicylate. Left in contact with NaOH you will form sodium salicylate, with
sodium acetate if you used asprin and will need seperating. Add acid to the salt and produce salicylic acid. This can be decarboxylated to phenol by
strongly heating it (distilling) in contact with broken glass or pumice, we dont have exact details of this method so some experimentation will be
needed, excess salycylic acid should be removable with sodium carbonate, which wont dissolve the phenol much.
The phenol itself wont be useful as is, you need a derivitive to get reasonable light yeilds. The most accessable method would be to nitrate it to
2,4 dinitrophenol. Less severe conditions will be needed than to make TNP, and mononitro products and TNP will need to be removed from the product.
Reacting that with the oxalyl chloride and a suitable base with an organic solvent in the absense of water gets you bis-(2,4 dinitrophenyl) oxalate.
It all seems to simple in hindsight.
The_Davster - 16-4-2004 at 14:58
I have found a small bottle in the drugstore under the name "salts of lemon", if you are wanting an OTC method and are not planning to
synthesise it yourself.
darkflame89 - 17-4-2004 at 00:38
Isn't salt of lemon a citrate salts?? I also found a big bottle potassium citrate in the pharmacy, but what does that have to do with the oxalic
acid??
darkflame89 - 17-4-2004 at 05:45
Ok, i found oxalic acid sold as some marble tile cleaner or something, so there is no need to synthesise that, thank heavens..
Saerynide - 27-4-2004 at 01:44
Glo sticks apparently make phenol and CO2 as they react. The only problem here is, how would you go about separating the dye from the phenol?
Distillation?
darkflame89 - 27-4-2004 at 01:50
Dye, no, i am trying to make this particular ester that would react with hydrogen peroxide, so that i can make my very own light sticks, cause i
can't find them around ,see.. phenols can be generated by the procedure stated by Marvin
Edit: sorry for misunderstanding, do we need to get the dye out? Why not just leave it there?
[Edited on 27-4-2004 by darkflame89]
Saerynide - 27-4-2004 at 02:05
Oh, you are trying to make glow sticks 
I thought you wanted the phenol for something else and that you might not want dye in there 
frogfot - 26-8-2004 at 09:55
Got a little problem with decomposition of wood by NaOH.. I used a book procedure, where they soak 50 g wooden shavings with a soln of 150 g NaOH in
300 ml water. This is then fused at 200-220*C in a cast-iron crucible for 3 h.
The problem is, stuff doesn't melt.. (well, book tells to fuse it, so I guess it suppose to melt) once water boils off temp reaches 200*C and
shavings decompose as expected. Beyond this, stuff remains as powder/lumps and I'm unable to hold recommended temp..
Once I overheated stuff and got a black mass.. book tells that final goo should be greenish. Note, they also use a gasburner, so theres no question
about regulated heating source..
So whats wrong? Anyone have experience with this synth? This would be truly a cheap and easy source of oxalic acid. Yields are told to be 28-40% from
the weight of wood.
Marvin - 28-8-2004 at 15:25
Sometimes the word fuse just means heat. Particulally in old books 100 years+.
You may find adding a small amount of KOH to the solution helps. Most of the books Ive read recommend using a mix of both hydroxides. Fownes
recommends 1 part KOH to 2 parts NaOH as a solution, mixing with sawdust (quantity not stated) and putting in thin layers on iron plates. The plates
are then heated gradually causeing them to lose some water, as well as swell up and give out flammable gasses, the plates are "maintained at 400F
(204C) for some hours care being taken to avoid charring which would cause loss of oxalic acid". Product should be a grey powder that can be
leached, leaving undissolved crude sodium oxalate.
The product tends to be rather impure and the full method also involves making the low soluability calcium oxalate, and then digesting this with
sulphuric acid to remove the calcium as sulphate. It seems like a lot of effort all told.
BromicAcid - 28-8-2004 at 18:02
I've read... somewhere (online reference so maybe you could look for it). That heating benzoic acid with copper benzoate and copper powder
yields phenol. Just something to look for.
frogfot - 29-8-2004 at 07:08
Book is from 1961, so yp, it's rather old..
Gonna try this with KOH added. But then synth becomes a bit more expencive..
It also seems that loss of oxalate would be increased, since potassium oxalate is more soluble..
It would be nice if reaction mix could be heated in kitchen oven, but I'm a bit concerned about the fumes..
Bromic, I've tested that reaction couple of times (mentioned on E&W with reference to a patent). The only catch is, one would need a reflux
column that's capable to separate phenole from benzoic acid and phenyl benzoate..
[Edited on 29-8-2004 by frogfot]