Bridging the Bottlenecks in Biohydrometallurgy: Enhancing Kinetics, Resource Utilization, and Sustainability for Scalable Metal Recovery

Biohydrometallurgy provides eco-friendly alternatives for extracting metals from primary and secondary resources. However, its industrial scalability is limited due to slow bioleaching kinetics, a lack of process adaptability to complex waste, and insufficient integration of sustainability assessments. This review addresses these challenges by examining recent advances in redox-controlled systems, microbial consortia engineering, and hybrid bioleaching techniques that enhance reaction rates and selectivity. The application of biohydrometallurgy to complex matrices, such as electronic waste and tailings, remains underexplored, necessitating the development of selective bioprocesses and robust microbial communities. Scalable and continuous bioreactor systems are also lacking, hindering commercial adoption. Moreover, few studies incorporate life cycle assessment (LCA) and techno-economic analysis (TEA), leaving uncertainties about environmental and economic performance. The inefficient recovery of critical raw materials such as rare earth elements and precious metals via biotechnological methods presents an additional gap. Addressing these bottlenecks through interdisciplinary innovations can transition biohydrometallurgy from laboratory scale to industrial viability. This review contributes to the IPMC 2025 theme by highlighting practical and sustainable approaches to improve metal recovery from low-grade and complex resources through biological processes.