Green technologies for mine wastewater treatment: Biosynthesized nanoparticles and enzyme-based catalysis

The application of biogenic metallic nanoparticles in catalytic wastewater treatment has gained significant attention as an eco-friendly alternative to traditional physical and chemical methods of water treatment. Their advantages, including low production costs, environmental friendliness, and ease of operation, have earned them a place among essential materials for sustainable remediation technologies. This has led to an increasing number of studies exploring nanotech-based catalytic processes to address wastewater pollution issues more effectively. Mining wastewaters, particularly acid mine drainage (AMD), pose a persistent environmental challenge due to their high acidity, elevated heavy-metal concentration, and complex geochemistry. Traditional physicochemical treatment methods often produce secondary pollutants, require high energy inputs, and generate large volumes of sludge. This review examines recent advancements in green biotechnology-based remediation approaches that utilize biosynthesized nanoparticles derived and enzyme-based catalysis for treating mine wastewater. this research paper evaluates the potential of biogenic metal and metal-oxide nanoparticles, produced through microbial or plant-mediated methods, to perform multifunctional remediation via adsorption, redox reactions, and in some cases, photocatalysis. it alsos explore the role of enzymes, particularly oxidoreductases, and their synthetic mimics, known as nanozymes, in detoxification through catalytic actions under mild, eco-friendly conditions. An analysis of recent literature highlights emerging themes, limitations, and translational challenges, such as nanoparticle stability, ecological risks, enzyme robustness in mining environments, and scale-up barriers. the paper proposes future research directions, integrating hybrid bio-nano systems, performing field-scale pilot testing, conducting life-cycle assessments, and developing novel acid-tolerant biocatalytic systems. This review emphasizes that green biocatalytic strategies hold the potential to transform wastewater management sustainably, but significant work is required to bridge the gap from promising laboratory-scale systems to field applications.