Biochar Derived from Agricultural Residues for Wastewater Contaminants Removal

The valorization of agricultural residues helps improve crop economic efficiency and alleviate environmental pressures. Owing to the merits of simplicity, high efficiency, low costs, and scalability, adsorption removal of contaminants using biochar has been widely investigated. The adsorption removal of organic and inorganic contaminants from wastewater using biochar derived from agricultural residue follows the principles of the circular economy and green chemistry, facilitating both environmental remediation and agricultural development. This review outlined the mechanism of biochar adsorption, the preparation of biochar from agricultural residues, and their applications for wastewater remediation. Furthermore, the economic evaluation and environmental impacts, as well as the future directions and challenges, in this field, have also been presented.