Development of Hydrometallurgical Processes for the Recovery of Critical and Precious Metals from Industrial Waste

The growing demand for critical and precious metals, alongside increasing environmental and geopolitical pressures, has spurred the development of sustainable and circular approaches to resource recovery. This doctoral research investigates the design, optimization, and implementation of hydrometallurgical and electrochemical processes for the selective recovery of valuable and criticals elements from different industrial and electronic waste streams. The study places particular emphasis on the use of organic acids, such as tartaric acid sourced from agri-food waste, as environmentally leaching agents. By integrating advanced experimental design methodologies with a suite of analytical techniques-including ICP-OES, XRD, XAS, and SEM-EDX-the research aims to enhance both the efficiency and the sustainability of metal recovery processes. Three representative case studies are presented: the closed-loop recovery of lithium from spent LiFePO4 batteries, the recovery of molybdenum from spent catalytic materials, and the recovery of silver from end-of-life photovoltaic panels. The findings contribute to the advancement of eco-innovative recycling strategies and underscore the potential of green hydrometallurgy within the framework of a circular economy.