Dissolving Am(IV)Oxide and gold

[Malama]

Hi

I am doing a diploma work on the subject recycling ionising smoke detectors.

The radiation source is Am(IV)dioxide that has been melted into a gold matrix.

What I wanted to do was to dissolve the gold and AmO and later use some separation technique to get the Am out.

The problem is that I did not manage to dissolve with aqua regia as I thought I would be able to.

I am using 5ml aqua regia for less than 1g of gold/AmO, some of it has been dissolved, but not at all as much as I would have guessed. I have it at room temperature and have been thinking of heightening the temperature to get better dissolving.

To go to even stronger acids then aqua regia feels a bit unsafe.

You have any ideas what could be a good thing to try, or any other thoughts about how to get the Am out without dissolving??

 

I’m not expecting anyone to solve everything for me, just thoughts that might help.

 

//Jon

[John Cuthber]

Where are you and do you have the apropriate license for such actions?

[Malama]

I am in Sweden, and yes i do.

I am in a Nuclear Chemistry department.

[John Cuthber]

OK you should be able to dissolve the lot in aqua regia- I think it works better hot (though boiling it will lose you some of the chlorine etc). Ypu might need more acid than you expect because there are losses of HCl etc. Anyway, the acid's cheap.

I'm not sure about recovering the Am from the solution. I would see how people ppt gold from solutions for recovering scrap gold, though I suspect a fair bit of the Am would stick to the gold.

The alternative would be to add a carrier and precipitate the Am and carrier while leaving the gold in solution.