# Pd & Pt boiling in HCL question



## kkmonte (May 28, 2013)

Ok, so I processed two honeycombs in HCl/Cl per Steve's instructions, I then raised PH and dropped with zinc powder, coarse filtered and filtered with charmin plug. Gathered all my PGM black powder together in a beaker, and I read on here that you should do 1 HCL boil (to get rid of any zinc that was left over) and then 3X distilled water boils. All my powders looked brownish/black, I didn't see any gray. So I boiled the powders in HCl for 5 minutes, let settle and decanted solution. The HCl had turned like a tea/brown color (see pic). I tested with stannous and It immediately turned black. See Stannous swab below. So I guess I dissolved some of Pd (even though i don't really see any green)? I thought I had read that hot HCl could dissolve Pd however a few other posts I read (or at least thought I read) said you should boil your blacks to get rid of any extra zinc. 

It doesn't look like I have any less powder in the beaker, but won't know until I dry and weigh. I only had approx. 2 grams before the HCl boil and distilled water boils.

Questions/comments welcome. Thanks.
Ken


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## Platdigger (May 29, 2013)

To take up any zinc, dilute hcl cold should have been sufficient. Along with your water rinses.


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## kkmonte (May 29, 2013)

Thanks platdigger, i'll be sure to do that next time, so 50/50 HCl and water cold first, then 3X distilled water boils ? 

I"ll add this liquid into my next batch of cats for re-precipitation.

Thanks.


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