The Separation of Gold, Platinum, and Palladium by Reversed-phase Partition Chromatography

Abstract

Abstract For the separation of gold, platinum(IV), and palladium, and for the isolation of gold from other metals, the reversed-phase partition chromatography has been used as a column process in which TBP is adsorbed on Daiflon(polytrifluorochloroethylene moulding powder) as the stationary phase and hydrochloric acid, as the mobile phase. The separation of the above three noble metals was successfully achieved by carrying out the elution with 3–4 n HCl, and the isolation of gold was attained well of itself by virture of the fact that gold is tightly retained on the column and is only released by letting concentrated HNO3 flow through the column. The concentration and separation of gold from various solutions, such as in the presence of a large amount of iron(III) or in the presence of 19 common metals and the above three noble metals, was achieved only by allowing gold to be retained on the column and allowing ther others to flow down with a 1 n HCl eluting solution. The behavior of the three noble metals in batch extraction was also examined under the same condition as in the partition chromatography employed here; a similarity was observed between the column and the batch extraction. The principal extracted species of the noble metals might be assumed to be a hydrated and solvated ion pair, such as H(H2O)nTBP6+·HPtCl6−.