extraction is electrolytic. Dissolution of crude zinc oxide, ZnO, in sulfuric acid gives zinc sulfate, ZnSO4 in solution. Electrolysis of the ZnSO4
solution using aluminum cathodes and lead alloyed with silver anodes gives pure zinc metal coated on the aluminum. Oxygen gas is liberated at the
anode.
sulfuric acid is also made in this process and is recycled to dissolve more zinc oxide forming zinc sulfate
well i have a platinum anode so i don't want to mess with lead
and aluminum cathode easy to find any one know if the zinc will react with very dilute sulfuric acid im guessing the reaction is like copper sulfate
and maybe the aluminum cathode gets consumed if they are in all the same electrolyte
i guess i could just use a salt bridge
melting points
680 ºC decomp. (anhydrous)
100 °C (heptahydrate)
70 °C, decomp (hexahydrate)
both 1 pound
>zinc powder
$12.44
$17.44 with tax and shipping
>zinc sulfate
$3.99
$9.99 with tax and shipping
and sulfuric acid can be recovered from it
and 5 pounds zinc sulfate
$10.99
$21.99 with tax and shipping
[Edited on 20-4-2011 by symboom]Bot0nist - 20-4-2011 at 15:19
Zinc is less than half the weight of the compound zinc sulfate. It would almost be worth it fiscally if not for the investment in time(lots) and
equipment. Still it would be fun though.
[Edited on 20-4-2011 by Bot0nist]symboom - 20-4-2011 at 19:30
i would more do it for the experience and the got to at least try it once. ill probably do it using a salt bridge just to be safe
last thing i want is just a bunch of H2 and O2 and no productroamingnome - 20-4-2011 at 20:12
this sounds real cool
with enough zinc you could make your self an electric car
and with enough renewable energy you can recycle the oxidized zinc.
symboom - 20-4-2011 at 20:42
my idea was more as using it to reduce MnO2 forming a slow thermite that is normally energetic and fast burning
Zn/MnO2 thermite
and for other pyrotechnics instead of using it in a disposable recyclable battery for an electric car and recycling the zinc oxide
but i guess the sky is the limit redox - 21-4-2011 at 17:56
I think (maybe I'm wrong) that you could simply add a piece of aluminum foil to the zinc sulfate solution. The aluminum would displace the zinc giving
aluminum sulfate and zinc metal. It might take a while though.Bot0nist - 21-4-2011 at 18:00
Quote:
**- add a piece of aluminum foil to the zinc sulfate solution.
Works with a CuSO<sub>4</sub>-5H<sub>2</sub>O solution to get Cu. Pretty violently in fact.
[Edited on 22-4-2011 by Bot0nist]Random - 3-5-2011 at 14:26
I tried putting Al into CuCl2 and it was violent reaction while putting Al into ZnCl2 didn't even cause reaction (or maybe it was very slow).symboom - 3-5-2011 at 17:55
that's interesting. Aluminum is used as the cathode i would thought it would be noticeable reaction. maybe could be the same with some other elements.Neil - 3-5-2011 at 18:24
**- add a piece of aluminum foil to the zinc sulfate solution.
Works with a CuSO<sub>4</sub>-5H<sub>2</sub>O solution to get Cu. Pretty violently in fact.
[Edited on 22-4-2011 by Bot0nist]
I've never managed to get that to work without adding a Chloride salt. Did you heat the mixture?
Zn and Al form some interesting intermetallics. If you get a nice coating of fine Zn powder all over the Al, I wonder if heating would be enough to
trigger a reaction. I have a feeling it would end up being too passivated with aluminum hydroxide goo. there is a phase diagram on page 27 of a Al/Zn
system. http://books.google.ca/books?id=Uimniogb0DEC&pg=PA25&...
[Edited on 4-5-2011 by Neil]symboom - 7-5-2011 at 19:46
my guess is the aluminum is has Cathodic protection and is slightly more reactive than zinc (zinc oxide and aluminum thermite shows this)once power is
turned off a battery effect might form as the aluminum becomes the anode in the battery and the platinum the cathode.Bot0nist - 7-5-2011 at 23:03
**- add a piece of aluminum foil to the zinc sulfate solution.
Works with a CuSO<sub>4</sub>-5H<sub>2</sub>O solution to get Cu. Pretty violently in fact.
[Edited on 22-4-2011 by Bot0nist]
I've never managed to get that to work without adding a Chloride salt. Did you heat the mixture?
[Edited on 4-5-2011 by Neil]
Sorry, I always add NaCl also. Off topic, but the resulting Cu formed can be easily powdered when dry and makes an amazing flash with
KClO<sub>3</sub> a touch of sulfur to get it to take flame.AJKOER - 12-6-2011 at 14:58
It turns out that the Al and CuCl2 is a known and as of yet, not completely understood reaction as to the mechanics of exactly why it proceeds so
vigorously (other than the protective Al2O3 coating is effectively removed).
My hint of the day is to prime the Al surface by pre-soaking in Acetic acid followed by thorough rinsing. Even if there is no apparent reaction, give
it 8 hours at room temperature (or heat it to speed things up). Unexpectedly, this priming works in trying to dissolve Al foil in NH4OH that otherwise
remains unreactive (this is an experiment that I have performed based on an article by a Al coating manufacturer noting the ability of Acetic acid to
disrupt the protective coating).
Good luck.
[Edited on 12-6-2011 by AJKOER]LanthanumK - 21-6-2011 at 03:00
If the protective coating is disrupted, won't the aluminium foil start reacting vigorously with the acetic acid?
