Trattamento e recupero di metalli preziosi e di base da rifiuti industriali attraverso processi idrometallurgici sostenibili e con approccio all'economia circolare

The recovery of material and energy from end-of-life products is increasingly fundamental for sustainable development. The most significant challenge for research in this sector is to find increasingly cutting-edge technologies that allow us to help the environment while generating profitable economic activities. Through the union of these two aspects, which until now may have seemed antithetical, we can talk about progress. From this standpoint, materials such as spent catalysts or electrical and electronic equipment are not seen as waste but as sources of supply, in many cases even better than natural ones. This thesis reports the studies conducted to develop and optimize several processes for recovering raw materials from different types of waste, such as Oil&Gas catalysts, printed circuit boards, photovoltaic panels, and permanent magnets. Through laboratory-scale experimental tests, process simulations, and the creation of mathematical models, it has been possible to have innovative and internationally competitive process solutions compared to those currently on the market. In this sense, a new process for the valorization of Oil&Gas catalysts has been developed and patented: the ORIM-CAT2 process. A process for recovering silver and silicon from end-of-life photovoltaic panels has been developed and is being patented. Two processes have been optimized for recovering precious and base metals from waste electrical and electronic equipment (Gold-REC1 and Gold-REC2) and a process for recovering rare earths from end-of-life permanent magnets.