condennnsa
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oxalic acid synthesis
I need some oxalic acid, but i can't find any to buy.
What would be the easiest way for the home chemist to oxalic acid?
I remember reading somewhere that it can be prepared from sucrose and nitric acid, with a V2O5 catalyst ... but that it also works without the
catalyst for a lower yield.
Has anyone tried this procedure? Is it worthwhile?
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not_important
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It's been covered here before, several threads. Try doing a little searching and you'll find them.
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JohnWW
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Sucrose + nitric acid is liable to give you the nitrate ester, sucrose octanitrate, or a partly esterified form, which like cellulose nitrate
(gun-cotton etc.) is an high explosive, so be VERY careful.
See: http://www.sciencemadness.org/talk/viewthread.php?tid=17 , also http://www.freepatentsonline.com/2081161.html , http://www.freepatentsonline.com/2165435.html , http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=1982... , http://www.caslab.com/Sucrose_octanitrate__3552-_-/ .
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Magpie
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http://www.sciencemadness.org/talk/viewthread.php?tid=12832#...
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Picric-A
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Not a chance of forming the nitrate if you use 40% nitric acid for the oxidising agent as you are supposed to!
Its true, nitrates may form if WFNA is used but you would have to be retarded to try that 
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The WiZard is In
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Buying is the antithesis of experimentalism. However, if you are willing
to give into the dark side ... you can buy a 500kg lot.
For sale by a NY City charity on eBay.
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The WiZard is In
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Quote: Originally posted by condennnsa  | I need some oxalic acid, but i can't find any to buy.
What would be the easiest way for the home chemist to oxalic acid?
I remember reading somewhere that it can be prepared from sucrose and nitric acid, with a V2O5 catalyst ... but that it also works without the
catalyst for a lower yield.
Has anyone tried this procedure? Is it worthwhile? |
-----
What you remembered can be found in Thorpe's
Dictionary of Applied Chemistry Try the 1922 ed.
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Vogelzang
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http://www.google.com/#q=oxalic+wood&hl=en&sa=2&...
http://files.buildsite.com/dbderived-f/dap/derived_files/der...
[Edited on 7-7-2010 by Vogelzang]
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Picric-A
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There are hundreds of wrriten examples of this reaction, ie, vogel.
The yield is not the best (off the top of my head ~30% at best) however sugar and nitric is cheap and to most, readily available! I am surprised you
can buy oxalic acid, it is cheap and it is in just about every wood preservative/treatment you can buy!
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entropy51
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In my part of the United States, all of the hardware stores sell good quality oxalic acid as wood bleach.
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Picric-A
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I'll second that for the UK.
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The WiZard is In
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Sorry I forgot to add - you can access it at Google.com/books.
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Random
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Can I use nitrate salt mixed with hcl instead of pure nitric acid?
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Picric-A
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Yes, i am sure, however yields would be worse still and the product would be harder to extract.
Try boiling down a 100ml solution of ethylene glycol in 30% nitric acid until 30ml remains then cool in ice. Oxalic acid will ppt. Yield ~72%.
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Random
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actually i am thinking about sucrose route with nitrate salt and hcl
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not_important
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some metal or ammonium nitrate MNO3 + HCl <==> MCl + HNO3
So you get a mixture of the two salts, and the two acids. And HNO3+HCl is aqua regia, or an approximation thereof. Release Cl2 and NOCl.
Ethylene glycol plus hypochlorite bleach with a nickle salt catalyst also works though the yields are lower than using pure HNO3 of the proper
concentration. Add the glycol slowly, with stirring. There's at ;east one thread on bleach+Ni as an oxidiser.
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Random
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I will check that metal too, just I am interested in hcl/nitrate salt method the most because that is what i mostly have. There should be no explosive
or very toxic things generated with hcl-nitrate salt and sugar?
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not_important
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As I said - HCl + a nitrate makes some NOCl + Cl2, both reasonably nasty without good ventilation. just for starters; plus it wastes the materials as
some of the nitrate is destroyed in those side reactions. The mixture is not a good one for anything but dissolving certain metals like gold.
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AndersHoveland
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I already posted this somewhere else, but I will repeat it again, to make it easier to find it in a search, since it could be potentially useful.
Wurtz found that ethylene glycol fused with solid potassium hydroxide yielded mostly potassium oxalate and hydrogen gas. The yield of hydrogen was 58%
of that required by the below proposed reaction
C2H6O2 + 2KOH --> K2C2O4 + 4H2
"THE LIBERATION OF HYDROGEN FROM CARBON COMPOUNDS", Shipley Fry, Else L. Schulze, Helen Weitkamp
J. Am. Chem. Soc., 1924, 46 (10), pp 2268–2275
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Adas
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You can also use copper to oxidise it, but this is too slow and unefficient.
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Hexavalent
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http://www.ebay.co.uk/itm/500g-Oxalic-acid-great-cleaner-rus...
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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