- Oct 30, 2015
Per the bold print - actually yes you can use formic acid to drop Pd direct from a Pd solution
It requires Ph adjustment (with sodium carbonate) as well as getting the ORP right long with heat
I believe 4metal posted a number of years ago the proper Ph - ORP & temp
here is a video by OwlTech showing how it is done - though he does not actually use Ph &/or ORP testing he simply uses chem reaction indicators when doing his chem additions - & the temp plays a critical roll
you need to move up to "about" the 19 minute mark - everything before that is about getting to the Pd solution for dropping the Pd with formic acid (& sodium carbonate)
You can use the same formic process for silver & as well (I believe) Pt --- not sure about gold or other PGMs
If you have Ag/Pd/Pt all in the same solution it well drop all of them so it's not selective in that way
It does not drop copper & metals above copper though if you over do the sodium carbonate (Ph adjust) you are likely to get copper & other metals to come down as carbonates
Thanks, I didn’t know that.
I have only seen it used on pure salts/ solutions.