Solvent extraction of platinum group metals

[Mgnaing]

I am using sodium peroxide fusions of pgms at 400 degree celsius for four hours . Then solvent extraction of osmium and then ruthenium , gold , palladium, iridium , rhodium and the last platinum . All precious metals call get to 99.95 except osmium and ruthenium which only 99.4 - 99.7 . How to make osmium and ruthenium to 99.95 without using distillation phase and only using solvent extraction phase ?

 

[Lou]

Ok,

Not a huge fan of peroxide fusions except in an analytical capacity. Much cheaper is sodium hydroxide/nitrate.

You want to set up for solvent extraction or are you already using it?

In general, Os/Ru are removed first, then silver chloride, then gold, then palladium or platinum (or both), then iridium is removed, and rhodium finally precipitated.

Distilling the metals should produce 3N5 material reliably. They are dangerous to distill but removing them up front is important if quality Pt/Pd/Rh/Ir is to be achieved.

Do you have ICP?

 

[Mgnaing]

I have XRF of my own and donot have ICP , I do ICP at my friend lab.