Sciencemadness Discussion Board

Nickel Oxidation/Dissolution

bereal511 - 25-11-2007 at 11:14

I cannot figure out a way to oxidize or dissolve nickel metal in a relatively short period of time without using nitrates. I'm running low on all sorts of nitrates, so I won't be able to use nitric acid (as the preferable route). And I do not have any power supply with enough amperage to dissolve the metal in a timely manner. I have a giant fresnel lens that I've been using to burn the nickel, but the security at my apartment complex seem to prowl around my area due to previous incidents of "fire hazards". Any suggestion would be much appreciated.

The_Davster - 25-11-2007 at 11:21

Peroxide and HCl does the trick for me. Took a day or two to dissolve the canadian nickels I was using.

nitroglycol - 25-11-2007 at 14:13

Aha, so peroxide is the trick. I tried Canadian quarters and HCl a few years back, and it took forever.

What kind of concentrations of peroxide are you talking about, though?

bereal511 - 25-11-2007 at 14:45

Yes, I would also like to know the concentrations.

The_Davster - 25-11-2007 at 15:26

I never really measured. I was going to evaporate the final solution down, so the nickels(10 of them) were in around 100mL~15-20% acid, and I added a dozen mL or so of 35% peroxide whenever bubbling slowed down, which was around twice a day or so. When I got tired of this after a few days I removed what was left of the nickels, and evaporated down the solution for nickel chloride.

nitroglycol - 25-11-2007 at 15:33

Hmm. So not much chance of using the 3% stuff from Shoppers Drug Mart I suppose...

The_Davster - 25-11-2007 at 15:40

Should not be an issue, you will just need larger volumes. I diluted my acid with water to 20%, you could use peroxide instead. You will end up with a rather huge volume of liquid per nickel, which would take a long time to evaporate.

nitroglycol - 25-11-2007 at 15:46

BTW, I thought Canadian nickels made after the late 1970s were alloyed with other metals, though the quarters and dimes stayed (almost) pure until 2000.

Until I saw your post, I was considering electrolyzing HCl solution with a quarter as an anode.

The_Davster - 25-11-2007 at 15:52

Apologies, I should have mentioned which years to use. 1956-1981 are pure nickel. I just exchanged rolls of nickels at the bank until I had a small pile of the correct years.

See http://en.wikipedia.org/wiki/Nickel_(Canadian_coin) for what years are what composition.
Quarters composition is listed here http://en.wikipedia.org/wiki/Quarter_%28Canadian_coin%29
But based on the mass of each and the stamped value of the coin, nickels are cheaper.

[Edited on 25-11-2007 by The_Davster]