The Leaching of Palladium from Polymetallic Oxide Ores using Alkaline Ferricyanide Solutions

The present study investigated a novel method of alkaline ferricyanide leaching to extract palladium (Pd) from Western Australian disseminated platinum-group metal (PGM) oxide ore that bears Ni and Cu. While cyanide has been used leach Pd, it is well known for its toxicity large consumption in the presence base metals. A more benign alternative, form ferricyanide, evaluated this research serve combined role lixiviant oxidant. Various parameters, such as concentration (1–30 g/L), dissolved oxygen level (up 25 ppm), pH (10–12), temperature (20–80°C), were evaluate Pd extraction. extraction was found be most sensitive with doubling when raised 20°C 80°C. highest 76.1% achieved at 10 g/L 11, DO 15 ppm, 80°C, 10% solids. system showed high selectivity over other metals (Pt, Co, Ni, Cu). co-extractions (Co, Cu, Ni) all below 2%, Pt range temperatures investigated. Although conventional cyanidation low (1 kg/t) slightly better performance extraction, significantly improved settleability filterability slurry considering finely ground nature high-clay content lateritic ores. In contrast, filter or settle poorly.