Hi
for a longer time, we have a quite complex problem sitting in our refining shop. Solution containing approx.:
34% Pd
9% Pt
2% Rh
rest is base metals mainly Fe, Co, Ni, some trace Pb, no Ag nor Au.
Metals are in form of chlorides in used up AR soln. Some nitric is certainly present.
We aim to recover enriched rhodium fraction, more than 50% by mass would be fantastic, as we work with quite a lot of this material. Also Pt and Pd fractions need not to be super pure, also mixed fraction PtPd would be fine.
I read whole bunch of papers, topics trough forum... And came with some DIY plan how to deal with the issue:
1. drop Pd with DMG - enriching soln with Rh, at pH ca 3 there shouldnt be much Ni coprecipitation, but if some, that is not big issue
2. drop impure Pt with NH4Cl along with some part of Rh as contaminant
3. rest of noble metals cement on something (Zn, Fe ?)
4. calcining impure ammonium hexachloroplatinate and melting remaining metal sponge in NaHSO4 - or leaching Rh with H2SO4 - which approach would be better ? or is there better approach than these ?
5. cemented noble metals leaching similar way as above.
I have no big experience in this field, but have great practical chemistry experience overall. Maybe im missing some point or its wrong in some way...
My question is: will it work ?
Better question: what´s your suggestion ? how could this be done better/more efficently ? is it even possible ?
Thank you in advance for your opinion
for a longer time, we have a quite complex problem sitting in our refining shop. Solution containing approx.:
34% Pd
9% Pt
2% Rh
rest is base metals mainly Fe, Co, Ni, some trace Pb, no Ag nor Au.
Metals are in form of chlorides in used up AR soln. Some nitric is certainly present.
We aim to recover enriched rhodium fraction, more than 50% by mass would be fantastic, as we work with quite a lot of this material. Also Pt and Pd fractions need not to be super pure, also mixed fraction PtPd would be fine.
I read whole bunch of papers, topics trough forum... And came with some DIY plan how to deal with the issue:
1. drop Pd with DMG - enriching soln with Rh, at pH ca 3 there shouldnt be much Ni coprecipitation, but if some, that is not big issue
2. drop impure Pt with NH4Cl along with some part of Rh as contaminant
3. rest of noble metals cement on something (Zn, Fe ?)
4. calcining impure ammonium hexachloroplatinate and melting remaining metal sponge in NaHSO4 - or leaching Rh with H2SO4 - which approach would be better ? or is there better approach than these ?
5. cemented noble metals leaching similar way as above.
I have no big experience in this field, but have great practical chemistry experience overall. Maybe im missing some point or its wrong in some way...
My question is: will it work ?
Better question: what´s your suggestion ? how could this be done better/more efficently ? is it even possible ?
Thank you in advance for your opinion