A process for extracting precious metals from spent printed circuit boards and automobile catalysts

In this work, a novel process to simultaneously extract precious metals such as gold, palladium, and platinum from spent printed circuit boards (PCBs) and honeycomb-type auto catalysts by smelting without the addition of any collector metals has been developed. The process uses metal components such as copper, tin, and iron contained in spent PCBs as the collector metal and spent auto catalysts as a slag formative. In each experiment, spent PCBs and auto catalysts were crushed, incinerated, and melted after adding fluxes and carbon. Up to 90% of the gold, palladium, and platinum in the raw materials were extracted in a Cu-Sn alloy phase.