PGM recovery

[kjavanb123]

All,

After heating a cat in concentrated AR, I realized the following formulas takes place, courtesy of Wikipedia.

Pt + 4HNO3 + 6HCl ---> (H3O)2PtCl6.nH2O + 4NO2 + 4H2O

Now, if i am correct the nitric evaporates since the AR is being heated in the process, but what is the purpose of adding ammonium chloride then?

H2PtCl6 + NH4Cl ----> ?

I am just trying to find out about the chemistery behind all these reactions.

Thanks
Kev

 

[lazersteve]

Ammonium Hexachloroplatinate

[NH4]2[PtCl6]

Steve

 

[Lino1406]

Hexachloroplatinic acid - highly soluble in water,
while its ammonium salt precipitates..