Dissolving Zr and Y in nitric acid

Bakery87

Hey all,

I have concentrated nitric acid (~70%), and I want to use it to dissolve Zr/Y metal. I've dissolved Y before, and I know it's as simple as putting metal into acid. The question I have, is there a known dissolution rate I should use to barely dissolve the metals in the acid? I wish to keep my metal molarity as high as possible in the finished solution. I also would like to avoid overheating of my mixture if possible. I know using concentrated acids can be tricky.

Any help would be appreciated.

M

chemisttree

Dissolution rate is strongly dependent on the surface area of the metals. Finely divided powders dissolve much more rapidly than shavings which dissolve much faster than briquettes or large lumps of metal. There is no way to answer your question without more information.

Bakery87

That would make the time shorter, which I don't care about. I can grind down a sample of my Zr chunks into a powder type form, but I am trying to avoid powder. Dissolving metal powder in nitric acid is violent, so I was hoping to just be able to calculate the minimum amount of acid to dissolve X grams Zr and Y grams Y.

I calculate it should be about a 4 M H+/ 1 M metal total, but what is the best way to add the acid to the metal? Add all of the metal to a beaker and then slowly add the measured amount of acid, or ....?

Bakery87

So, as it turns out, one can not dissolve Zr in nitric acid, hydrochloric, or others. HF seems to be the route, or possibly a mixture of H2SO4/HCl or perchloric acid. There are many conflicting reports on the subject. It appears to be related to how the Zr was prepared in the first place.

If I could find out how to make zirconyl nitrate from the metal, that would also be very helpful, and I plan on making another post on the subject.