Hydrometallurgical processes allow for the solid-liquid extraction and recovery of metals from minerals and ores. These processes are usually complex in their thermodynamics, kinetics, and hydrodynamics, which causes the description and comprehension of hydrometallurgical processes to become challenging. Thus, this research branch is essential to unveil and enhance environmentally and economically sustainable solutions to modern day problems. As a result, we focus on designing hydrometallurgical processing stages that include leaching processes and pretreatments to improve extraction or reduce reagent consumption.