Development of Innovative and Sustainable Methodologies Applied To the Recovery of Gold and Critical Elements in Integrated Circuit Boards

This study aimed to present the physical and hydrometallurgy processes using an eco-friendlier leaching method to extract iron (Fe), copper (Cu), zinc (Zn), gold (Au) and silver (Ag) from wasted printed circuit boards (PCBs).The physical processing study allowed to obtain a sample manly composed of metals to proceed with the hydrometallurgical process.For the hydrometallurgical process, selective leaching was studied, and the optimized results for the 1st and 2nd steps will be presented.In the 1st step, it was possible to extract the most amount of Fe, more than 80%, with a low extraction of Cu.In the 2nd step, the remaining Cu (>80%) was extracted.Au and Ag present unique properties, such as electrical conductivity and high resistance to corrosion, making them ideal candidates for electrical devices.Last years, electronic waste (e-waste) has grown significantly, with a large portion ending up in landfills, including spent PCBs that contain these valuable metals.Therefore, a study of the 3rd leaching step will be presented to extract Au and Ag from PCBs.Preliminary results demonstrate that it is possible to extract 54% of Au and 55% of Ag using thiourea and Fe (III).