Zhong, Lai, et al (2024) Synthesis and environmental applications of biochar-supported nano-zero-valent iron composites: a review. Environmental Chemistry Letters. https://doi.org/10.1007/s10311-024-01712-8

In the face of escalating environmental pollution, the necessity for effective and sustainable contaminant removal techniques becomes apparent. The reviewed biochar-supported nano-zero-valent iron composites, synthesized from wood, sludges, and agricultural waste, demonstrate promising potential in removing heavy metals from waters and soils, achieving removal rates of 90% and above. The composite’s performance is influenced by factors such as biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More feedstockFeedstock refers to the raw organic material used to produce biochar. This can include a wide range of materials, such as wood chips, agricultural residues, and animal manure. More, pyrolysisPyrolysis is a thermochemical process that converts waste biomass into bio-char, bio-oil, and pyro-gas. It offers significant advantages in waste valorization, turning low-value materials into economically valuable resources. Its versatility allows for tailored products based on operational conditions, presenting itself as a cost-effective and efficient More temperature (typically within 300–1000 °C), and iron/carbon ratio (e.g., 4:1, 2:1, and 1:2). Removal mechanisms encompass adsorption, reduction, and co-precipitation. The discussion extends to optimizing preparation methods, real-world applications, and addressing removal mechanisms for complex pollutants.