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Dangle89
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Uses for H2WO4???
Hello all 
Does anyone know any uses for Tungstic Acid (H2WO4)?
I have heaps from dissolving about 150g of 2% Thoriated welding rods in H2O2 and figured I would check if it was useful before disposing of it.
Only thing I have done is make some Na2WO4 and that was only because I couldn't find anything else to do with the H2WO4!
I'm sure someone out there will hate me for saying this (as they have probably spent their whole career working on tungsten compounds) but tungsten
compounds seem boring as bat shit!
Thanks in advance
Dangle
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deltaH
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Make heteropolyacids, e.g. phosphotungstic acid. It's a strong acid catalyst.
[Edited on 29-7-2015 by deltaH]
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diddi
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I really like tungsten. don't go dissing it to much. you have to admire its density at least.
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byko3y
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Yes, the heteropoliacid is a nice application for the tungstic acid.
The other usefull compound is the one you've already made - tungstate is a catalyst, which can be used for PTC+H2O2 oxidation of water-insoluble (at
least partially) alcohol to aldehydes/ketones, maybe it will work for epoxidation too.
Dangle89, I was not able to find the procedure for oxidation the tungsten via H2O2. In fact, I was looking for that simple procedure, could you post
it here?
upd2: okay, I've managed to find something http://pubs.acs.org/doi/abs/10.1021/ac60176a021?journalCode=...
[Edited on 29-7-2015 by byko3y]
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Dangle89
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Indeed the density is impressive! Have read a bunch of stories of people drilling out gold bars and filling them with Tungsten rods (density for W and
Au is almost identical - Au : 19.30g/cm3 - W : 19.25g/cm3)!
Here is the video I first saw it on:
https://www.youtube.com/watch?v=fsMxha7ZC_Y
and here is one of a very few papers on the subject:
http://pubs.acs.org/doi/abs/10.1021/ac60176a021
Dissolving W metal with H2O2 does not appear to have been researched in great depth (as far as I can see).
Hope that helps
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Dangle89
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Hahaha that is what I mean 
Every time I see a paper on the subject it is just copy's of the same thing
Could be (possibly?) an interesting subject for someone with better skills and facility's than me to research some more
Dangle
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diddi
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so have you tried the youtube method? I hope you didn't use the same music in your lab and that your beakers weren't sponsored by Tupperware
and did you try for the pure metal
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Dangle89
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Na haven't tried pure W.
Aim of my experiment was to extract ThO2 but figured I would save the "waste" product in case it ever came in handy
Also without using heat took about 4-5 weeks, changing the 100ml 50% H2O2 bath weekly, for the rods to dissolve!
Hehehe  na my "beaker" for this experiment was a jar as knew it would take a
while and didn't want to have a real beaker out of action for that long!
Music in the vid is not my style either
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byko3y
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Tungsten has 4d electrons and same electronegativity as chromium and molybdenum, that's why they are similar. I can't remember a lot of interesting
experiments with those elements, it's all pretty much about oxidizing something.
For some reason chromium never forms heteropolyacid, while tungsten does not form ditungstic acid.
Lower oxidation states of tungsten, when combined with nonmetals with low electronegativity, give rock hard compounds like tungsten carbide and
tungsten silicide, that's why they are pretty useless for organic chemistry and are relatively harder to produce.
It does not accepts electrons, thus forming no hydrides or alkaline salts.
Application of tungsten and molybdenum in organic chemistry is all about ligands. Even in the PTC-H2O2 case the reaction is driven by PTC-WO5-H2O
complex http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Servic...
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annaandherdad
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I'd like to know how they make tungsten filaments for incandescent light bulbs, with the tiny helix superimposed on a larger helix etc.
Any other SF Bay chemists?
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battoussai114
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I have some pure W welding rods here, I'll try to break a piece of it and leave in H2O2 to see what happens (not dissolving the whole thing, someone
broke my carbon rods and I only have tungsten left for my arc furnace).
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deltaH
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Tungsten bronze
I don't know what kit you have, but tungsten bronze looks and sounds very cool.
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diggafromdover
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Make the Tungstic Acid into a salt and ship it around.
Enjoying second childhood with REAL chemistry set.
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Dangle89
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Wow! That looks amazing! Not sure how easly I could make it and did some research:
https://books.google.com.au/books?id=N-QRBwAAQBAJ&pg=PA1...
Page 139 if the link wigs out.
One of the methods mentioned electrolitic reduction of WO3 (dehydrated H2WO4) and Na2WO4 at 800C. I dont know if I have the facilitys to do this but
would it be possible to make an impure sample by heating a mixture of WO3 and Na2WO4 in a crucible with a MAP gas torch while carbon electrodes sit in
the mixure? Or would this need to be done in an inert atmospere with a diferent method of heating? I know my method (if it works at all) would make
quite impure samples but I am cool with that
Just looks sooooo amazing and now I have seen that stuff I want some!
diggafromdover - It is already a yellow powder so wouldnt be hard to ship as it is if you want some
Thanks everyone
Dangle
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deltaH
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I was wondering if it can't be made from igniting a tiny amount of sodium metal and tungsten trioxide directly... a kinda sodium tungsten thermite
Would be VERY dangerous, so be warned that I wouldn't try this in more than milligram amounts to start with and unless properly experienced and kitted
out for the dangers. It could very well explode.
If it doesn't explode, it would be a very easy way to make these types of tungsten bronzes, perhaps even molten? Imagine if it were castable! 
I also wonder if one could use lithium metal (potentially recoverable from lithium batteries) to make a lithium tungsten bronze. However, I don't know
if these bronzes even form with lithium?
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Dangle89
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Quote: Originally posted by deltaH  | I was wondering if it can't be made from igniting a tiny amount of sodium metal and tungsten trioxide directly... a kinda sodium tungsten thermite
Would be VERY dangerous, so be warned that I wouldn't try this in more than milligram amounts to start with and unless properly experienced and kitted
out for the dangers. It could very well explode.
If it doesn't explode, it would be a very easy way to make these types of tungsten bronzes, perhaps even molten? Imagine if it were castable!
I also wonder if one could use lithium metal (potentially recoverable from lithium batteries) to make a lithium tungsten bronze. However, I don't know
if these bronzes even form with lithium? |
Hi deltaH
Yup the Li bronze does exist A reference for it is in that link above
Li2CO3 +WO3 = LiXWO3 (at 780-850C)
Hmmm... I think I read somewhere about a Thermite type reaction to make it but pretty sure it was under inert atmosphere  Will do some more research to see if it can be done in a backyard setup!
Might be worth a shot though! Once I am satisfied it won't be a CuO + Al type reaction I might give it a go!
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deltaH
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It's exactly the CuO + Al reaction I was thinking off
WO3 is a pretty powerful oxidant and obviously Na/Li are nutty strong reductants, so, yeah... BOOM! (probably)
| Quote: | | Li2CO3 +WO3 = LiXWO3 (at 780-850C) |
I doubt this will work, the tungsten bronze is a partially reduced tungsten trioxide, so you need a reducing agent.
Nice to see that lithium bronze is known.
Here's a grand idea, make a thermite this way using the following anhydrous reagents (or else it will blow up)!
6Al + 11WO3 + 9Na2WO4 =>
3Al2O3 + 20Na[0.9]WO3
According to wiki, 0.9 sodium = golden coloured bronze.
I will go out on a limb here and say you might make blue coloured stuff at low sodium content (if this is anything like the electride trends).
Anhydrous sodium tungstate melts at 698°C, which is nice in terms of making this an easy starter.
Tungsten trioxide melts at 1,473 °C. Presumably the sodium in the bronze makes it melt a lower acting as an alkali flux, so if you're lucky, you
might get a melt of the bronze and can cast with it
You can presumably calcine both your tungstic acid and sodium tungstate simultaneously in a crucible using a gas torch. Hopefully, this will make a
brittle tungsten trioxide soda 'glass'. Then simply grind it for the thermite reaction.
I can just see the next craze, tungsten bronze statues
Maybe they won't even tarnish?!
Frak, there must be a ton of money to be made with this if it could be made to work...
[Edited on 1-8-2015 by deltaH]
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Dangle89
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Wow! Had to share this! It talks about Li, Na, K, Rb AND Cs Tungsten Bronzes
http://actachemscand.org/pdf/acta_vol_05_p0372-0378.pdf
Only problem is the purification uses HF acid I crap my pants just thinking of
HF's toxicity and knowing my luck I would spill it all over myself and be dead in a week For instance every single time I work with AgNO3 I somehow get a black spot on my hands! I always wear gloves and is probably as I am
working with 100g+ of Ag metal at a time and know it wont hurt me too bad :-P Might be more careful if it was HF!!!
The Li2CO3 +WO3 = LiXWO3 (at 780-850C) thing said it was with electrolysis going. I don't really know how electrolysis effects compounds (electricity
runs on bad voodoo and dark magic hehehe ) so maybe that helps the reaction
along? The only electrolysis I understand is breaking salts i.e. NaBr = Na(s) + Br(g/l/vapor - whatever you want to call it).
I will experiment on a few different methods and see if I can make something work Not this weekend though as it is raining here
Tungsten bronze statues is probably the coolest thing I have ever heard! Just has a really nice ring to it
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deltaH
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Ah ok, yes then reduction is effected electrolytically. I still think a thermite is much simpler and if manageable, would work to make larger batches
(important for tungsten bronze statues )
Nice find with that paper!
I see Wright (ref. 7 in the paper) had prepared them "by reduction of polytungstates with zinc", so not so far removed from my idea with the thermite
Personally, I would not work with HF outside of a professionally kitted lab!!!
I expect the thermite to be pretty fast, but because much less aluminium is used, it might be better behaved. Possibly the low aluminium might make
the thermite reaction not proceed at all, but I doubt that.
Also nice to see that polytungstates form, thus I think you certainly can fuse crude tungstic acid and sodium tungstate at high temperature to form
the glass precursors I spoke of earlier.
[Edited on 1-8-2015 by deltaH]
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Dangle89
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Yeah no intention of using HF in the foreseeable future!
Was looking for a "safer" way to fluorinate compounds than using F2 or HF at one point. Was looking at NH4HF2 but gave up one I saw that it makes HF
when mixed in water
Plus in my research recently on legality of importing things found it was on ASIO's (Australia's CIA) list!
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deltaH
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Time to source lots and lots of tungsten metal. Pure tungsten metal dissolution in H2O2 is clean and trivial. Partially neutralising the product and
then calcining at <<1000°C to made tungstate soda glass is also fairly trivial. Don't know how easy it is to buy aluminium powders by you, but
I'm guessing that's not so trivial?
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Dangle89
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Surprisingly I don't have any Al powder at the moment
I will have to buy some now!
Damn i'm excited for this NaxWO3!!!
Buying pure W can get expensive though Might just have to go commercially pure in
the short term!
[Edited on 1-8-2015 by Dangle89]
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deltaH
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Me tooooo!!!!
If you ever do it, wait for it to cool down before digging out the bronze, else you risk oxidation in air if it's still very hot. I presume that's a
problem at high temperatures.
If the tungsten bronze doesn't melt, then purifying it from the Al2O3 might be a problem
What about using OTC glass etching solutions to dissolve the Al2O3?
[Edited on 1-8-2015 by deltaH]
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Dangle89
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What are some OTC glass etching solutions?
I'm fairly sure all HF (even those low concentration rust removers) products have been banned in AUS. Either for health reasons or because they
figured someone was gonna buy cheap $5 rust remover, then spend a bazillion dollars on an UF6 enrichment plant for their back yard
The Only other compound that got a mention on wiki was NaF. Will check out an art store to see if they have anything when the sun comes up If I ever get to sleep before that
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battoussai114
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| Quote: Originally posted by Dangle89 | What are some OTC glass etching solutions?
I'm fairly sure all HF (even those low concentration rust removers) products have been banned in AUS. Either for health reasons or because they
figured someone was gonna buy cheap $5 rust remover, then spend a bazillion dollars on an UF6 enrichment plant for their back yard
The Only other compound that got a mention on wiki was NaF. Will check out an art store to see if they have anything when the sun comes up If I ever get to sleep before that |
Well, lucky me that I've got my nuclear centrifuges up and running before they figured it around here :p
Jokes aside, I think phosphoric acid also attacks Aluminum Oxide and it should be available OTC, not sure how it would react with the tungsten
bronze...
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