jamit - 7-4-2016 at 06:19
Recently I was able to purchase a large quantity of nickel oxide. Now I know there are two possible nickel oxide. Nickel II Oxide, NiO and nickel
III oxide, Ni2O3. The former is suppose to be green and the latter black. I have the black nickel oxide.
My problem is this: I have tried to make nickel salt starting from nickel III oxide but it won't dissolve very well in any of the mineral acids -
hcl, hno3 and h2so4.
I read on Google that nickel III oxide is calcined? therefore it won't dissolve in acids? Is there a way around this problem? How does heating it
at high temp calcine the nickel oxide and why won't it dissolve in acid? I tried heating it and it does dissolve somewhat but not much. Any help
would be appreciated! Thanks.
[Edited on 7-4-2016 by jamit]
blogfast25 - 7-4-2016 at 09:38
It's quite common for metal oxides to become very resistant to acids on prolonged calcination.
Ni(+3) is quite a powerful oxidiser, so if you react it with something that is easily oxidised you might get some reaction going.
A mixture of dilute acid and H2O2 might work because in acid conditions peroxide is easily oxidised:
H2O2 ===> H2O +1/2 O2
No guarantee but worth a try, IMHO...
Or try fusing with an excess of anhydrous NaHSO4.
[Edited on 7-4-2016 by blogfast25]
jamit - 7-4-2016 at 12:49
Thanks blogfast25. I'll try the acid and hydrogen peroxide first before trying the fusing of bisulfate. I'll give an update in a day or two.