Simultaneous extraction and preconcentration of palladium and platinum from alkaline cyanide solution by hexadecylpyridinium bromide.

A range of factors influencing the extraction and preconcentration efficiency were investigated and the results showed that, at a concentration of hexadecylpyridinium bromide of 0.05 mol/l, an n-octanol content of 30 vol%, an organic-aqueous phase ratio of 1:5, a pH value of 10.5 and a contact time of 5 min, the palladium(II) (less than 70 mg/l) and platinum(II) (less than 60 mg/l) in alkaline cyanide solutions were transferred from the aqueous into the organic phase. Ammonium thiocyanate solution was employed as a stripping agent and the extraction mechanism was elucidated using slope analysis, Fourier transform infrared spectroscopy and ultraviolet spectroscopy. Application of the method to the extraction of palladium(II) and platinum(II) from the leaching cyanide liquor of a platinum-palladium flotation concentrate gave an enrichment factor of 15 and a recovery rate of more than 95%.
A range of factors influencing the extraction and preconcentration efficiency were investigated and the results showed that, at a concentration of hexadecylpyridinium bromide of 0.05 mol/l, an n-octanol content of 30 vol%, an organic-aqueous phase ratio of 1:5, a pH value of 10.5 and a contact time of 5 min, the palladium(II) (less than 70 mg/l) and platinum(II) (less than 60 mg/l) in alkaline cyanide solutions were transferred from the aqueous into the organic phase. Ammonium thiocyanate solution was employed as a stripping agent and the extraction mechanism was elucidated using slope analysis, Fourier transform infrared spectroscopy and ultraviolet spectroscopy. Application of the method to the extraction of palladium(II) and platinum(II) from the leaching cyanide liquor of a platinum-palladium flotation concentrate gave an enrichment factor of 15 and a recovery rate of more than 95%.