Extraction of Iron and Other Metals from Copper Tailings through Leaching

Currently, mining operations have increased the generation of tailings, which contain a variety of elements that can be valorized. In this research, tailing samples were leached with hydrochloric acid of concentrations greater than 3 M, considering the monitoring of iron, copper, aluminum, calcium and magnesium, as relevant elements of the leached solution. Time and temperature were also studied. The original tailing sample was taken by trial pits, and a size distribution analysis was performed. The process generated an insoluble solid, rich in aluminosilicates, and an acid liquid solution with different metal ions. Elemental analyses were performed on liquid samples by Atomic Absorption Spectroscopy (AAS), and solid samples by Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDX) and X-ray Diffraction (XRD). Results showed an increasing trend of the iron concentration as a function of the acid concentration. However, copper is not affected by the change in acid concentration, but by time and temperature. Aluminum decreases with acid concentration, keeps constant with time, and yields at 50 degrees C. In the range of the studied parameters, calcium and magnesium showed a variation without a clear trend. The elements in the acid solution prepared with a tailing from northern Chile can be recovered for subsequent applications.

Automated summary

In this research, tailing samples were leached using hydrochloric acid to investigate the effects of time, temperature, and acid concentration on the extraction of iron, copper, aluminum, calcium, and magnesium. The results showed that iron concentration increased with acid concentration, while copper was affected by time and temperature, and aluminum decreased with acid concentration. Calcium and magnesium showed no clear trend in variation.