lazersteve said:
You should be able to have success precipitating the Pd directly as a metal with SO2 or zinc. You can recover the red colored Pd salt by adding ammonium chloride directly. The red salt will need to be purified via this method:
Purifying Pd
Check your left over solutions with DMG.
Steve
Steve,
I found the ammonia/HCl process for repuricication of palladium on pg 177 of Hoke's book and the reference you gave above with pictures should get me through that process.
I can see where using zinc to get the Pd metal would also bring down the Pt and contaminate my Pd.
Therefore, I would like to precipitate the red Pd salt with ammonium chloride and then purify with ammonia and hydrochloric acid as instructed above.
But I am a bit confused about adding ammonium chloride directly to the palladium/nitric solution to get the red powder.
I can not find this procedure in Hoke. Of course, there were no cats leached in HCl/Cl back then either.
She says that adding ammonium chloride to a palladium solution (prepared with AR) will produce no precipitation - C.M. Hoke pg 108 para 3
And then she goes on to say that sodium chlorate must be added a crystal at a time to precipitate the palladium.
I realize that the palladium solution that I am working with was NOT prepared using aqua regia - only nitric acid.
I will add the ammonium chloride directly to the palladium/nitric solution as you recommend. Just looking for some clarification.
On page 156, Hoke mentions that some, "considerations ... are not easily explained to the non-chemist" so I will take that and apply to this step.
Thank you for your help!
kadriver