A review on recent advances of biochar from agricultural and forestry wastes: Preparation, modification and applications in wastewater treatment

Biochar, an incredibly versatile and functional biomass material, has garnered significant attention for its myriad applications in the field of wastewater treatment as adsorbents and agriculture as a soil amendment. This paper provides a summary of different feedstock materials for biochar production, physicochemical properties, preparation methods, and major factors in the preparation process. Furthermore, different strategies such as surface modification were discussed to optimize the properties and capabilities of biochar. Biochar derived from agricultural and forestry waste has demonstrated promising performance in the removal of pollutants through various mechanisms, including adsorption, advanced oxidation, bio-enzymatic treatment, and membrane processes. For example, they have good results (close to 100%) against dyes (Acid orange 7 (AO7), methylene blue (MB)), antibiotics (Sulfamethoxazole (SMX)), heavy metals (Cr(VI)). However, the widespread commercial adoption of this technology has been hindered by several challenges, including high energy costs, practicality and stability concerns related to biochar, and potential harmful effects associated with chemical modification. By addressing these hurdles through ongoing research and innovation, biochar-based solutions can be further developed and optimized for widespread adoption in environmental remediation and sustainable waste management practices.