Collective PtPdIr Trace Precipitation By An Organic Agent
(selective for Pt Pd Ir, selective against Rh Ru, Cu Ni Pb and other base metals)

even some globally active refiners still rely on old pollutive aqua regia refining
this process can help to
+ recover values
+ minimize waste


useful separation scheme for

typical process data


1. Pt Pd Ir trace precipitation from highly acidic spent process liquors / filtrates after aqua regia treatment followed by inefficient classical Pt Pd Ir salt precipitation

=> this is a values recovery process

benefits
no prior neutralization
no additional salination of liquors
replacing unselective cementations avoiding base metal dilution
 

typical pregnant liquor /feed
10 - 100 mg/l Pt, Pd, Ir
10 g/l Cu, Ni, Pb

typical yield
> 99 %  Pt, Pd, Ir recovery
in the precipitate
< 5 mg/l Pt, Pd, Ir each
in the barren liquor
> 95% Cu, Ni, Pb
in the barren liquor


2. Pt Pd Ir trace precipitation in Rh concentrate solutions; process may be part of the Rh refining

=> this is a purification process

benefits
superior simplicity of rhodium purification
 

typical pregnant liquor /feed
3 - 10 g/l Rh
> 10 mg/l Pt, Pd, Ir traces
 
typical yield in purified concentrate
> 95 % Rh



Please note :
A level of 100 ppm Pt in a filtrate at 1500 USD/troz
means a value of 4822 USD/m3 !