As critical metals, the recycling of platinum group metals for the last decade attracted attention of reseracher especially in EU in order to balance the demand for these metals, thus to convert a previously disposable material as secondary sources into a valuable renewable resource. The cementation method can be defined as the replacement reaction between two metals i.e. cemented metal and cementator. It is the reduction of more noble metal ions in the solution to a metallic state by an electrochemically less noble metal going into the solution. Cementation method is cheaper and more practical to obtain palladium metallic powder and requires no pre-investment cost in the application of the method and it can be applied easily in the industry, which is one of the most important advantage.
The aim of this study was to recover palladium from plating solutions utilized in automotive industries by cementation by metallic copper powder, and to optimize reaction parameters. In order to reach this aim, Pd plating solution used in automotive industry was provided and dispersant agents present in this plating solution using H2O2 as well as sodium hydroxide were eliminated. The controlled solution by arranging its pH 1.0 in order to obtain 2 Lt of 634 ppm Pd (II) solution was obtained. This study was conducted at 25 oC in a thermal shaking bath to provide homogenous heat transportation during the process. The results showed that the yield of 99.41 % was obtained using 100 mg of Cu for 60 min of cementation.
Anahtar Kelimeler: Palladium plating solution, cementation, copper
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