Biochar from phytoremediation plant residues: a review of its characteristics and potential applications

Phytoremediation is a cost-effective and eco-friendly plant-based approach promising technique to repair heavy metal–contaminated soils. However, a significant quantity of plant residues needs to be properly treated and utilized. Pyrolysis is an effective technology for converting residues to biochar, which can solve the problem and avoid secondary contamination. This paper reviews the generation, and physicochemical properties of biochar from phytoremediation residues, and its application in soil improvement, environmental remediation, and carbon sequestration. In spite of this, it is important to be aware of the potential toxicity of heavy metals in biochar and the environmental risks of biochar before applying it to practical applications. Future challenges in the production and application of residue-derived biochar include the rational selection of pyrolysis parameters and proper handling of potentially hazardous components in the biochar. Graphical Abstract