Biochar/metal nanoparticles-based composites for Dye remediation: A review

Abstract

Dyes pose a significant environmental hazard due to their widespread use and tenacity in water bodies, resulting in adverse ecological and health effects. Many strategies have been investigated for the removal of dyes, and adsorption has emerged as a viable technique. Biochar-based adsorbents provide a sustainable alternative because of their high adsorption capacity, variable surface characteristics, and widespread availability. Biochar has improved adsorption properties similar to specific surface area, porosity, and total pore volume when mixed with metal nanoparticles due to synergistic interactions. It is crucial to comprehend the adsorption isotherm and kinetic models that control dye adsorption onto biochar because they provide insight into the mechanism and equilibrium behavior, respectively. The adsorption process's viability and energetics are further clarified by thermodynamic studies. Experiments and parameter optimization are guided by computational studies that use methods such as density functional theory (DFT) and response surface methodology (RSM) to optimize adsorption processes by giving insight into the system's relationship between multiple independent variables and multiple response variables and electron structure. This review also highlights the cost-effectiveness and sustainability of biochar/metal nanoparticle composites by discussing techniques for their regeneration and reuse and also explains the adsorption mechanism of dye by biochar/metal nanoparticle composites.

Keywords

• Biochar metal nanocomposite
• Adsorption isotherm
• Dye remediation
• Adsorption kinetic
• Adsorption thermodynamic
• Regeneration