Platinum group metals smelting

All the platinum group metals are isolated from platinum concentrates which are commonly obtained either from anode slimes in the electrolytic refining of nickel and copper, or as converter matte from the smelting of sulfide ores. The details of the procedure used differ from location to location and depend on the composition of the concentrate. Classical methods of separation, relying on selective precipitation, are still widely employed but solvent extraction and ion exchange techniques are increasingly being introduced to effect the primary separations (p. i 147). 

The platinum group metals (Ru, Rh, Pd, Os, Ir, and Pt), Ag, and Au are called precious or noble metals. Nobility and catalytic activity are unique properties of precious metals, that result in a wide range of applications, such as catalysts in various industrial fields, in electronic industries, and in jewelry. The chemical and physical properties of each precious metal are shown in Table 1. The determination of precious metals attracted the interest of analysts and developed rapidly because these metals are valuable and rare, and also very important for many products. Their concentration levels are very low in many natural sources, metallurgical intermediates, and environmental samples. Furthermore, precious metals are collectively handled in the analytical chemistry field, because of the close resemblance of their chemical properties and behavior. Precious metals are the subproducts in copper, zinc, or lead smelting and refining, which is the most important source of precious metals. Whereas many analytical methods for the ultratrace determination of precious metals in environmental or biological samples were recently published with the development of high-sensitivity analytical instruments, the classical fire-assay has been widely applied for the accurate determination of expensive precious metals. 

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