Alternative Sources of Raw Materials Emerge Amid Geopolitical Uncertainty

Research from the Polytechnic University of Madrid has highlighted the growing importance of mining wastes as alternative sources of raw materials. The study, funded by the Ministerio de Ciencia, Innovacion y Universidades and the European Union NextGenerationEU, examined the potential of hydrometallurgical processes in extracting copper from tailings deposits. The findings suggest that mining wastes can be a viable source of critical raw materials, including copper, zinc, cobalt, and arsenic, which are in high demand due to the depletion of principal ore deposits.

Key Takeaways:

• The study found that mining wastes can be a significant source of copper, zinc, cobalt, and arsenic, with up to 92.5% of copper extraction possible through hydrometallurgical processes.
• Two hydrometallurgical approaches were studied: acidic leaching with and without activated carbon, and alkaline leaching with glycine solutions. The results showed that alkaline leaching was more effective in copper extraction at pH 10-10.5.
• Temperature played a crucial role in reaction speed and copper precipitation in alkaline conditions. However, the glycine solution at pH 10-10.5 showed high selectivity for copper over other metals.
• The research also demonstrated the potential of mining wastes as a source of arsenic, with up to 51% dissolution possible at pH 12.5.
• The study's findings have significant implications for the mining industry, particularly in regions with limited access to principal ore deposits.

Statistics:

• Up to 92.5% of copper extraction was possible through hydrometallurgical processes.
• Alkaline leaching with glycine solutions showed high selectivity for copper over other metals at pH 10-10.5.
• Temperature played a crucial role in reaction speed with 71-76% copper extraction possible at ambient temperatures.
• Mining wastes can be a significant source of arsenic, with up to 51% dissolution possible at pH 12.5.

Sources:

• Advances In the Development of Hydrometallurgical Processes In Acidic and Alkaline Environments for the Extraction of Copper From Tailings Deposit. Minerals, 2025;15(6):550.
• NewsRx. Reports on Chemicals and Chemistry from Polytechnic University of Madrid Provide New Insights (Advances In the Development of Hydrometallurgical Processes In Acidic and Alkaline Environments for the Extraction of Copper From Tailings Deposit). News of Science. July 27, 2025; p 3021.