Structural and Adsorption Properties of ZrO 2 ‐Incorporated Sugarcane Bagasse Biochar for Malachite Green Dye Removal

ABSTRACT The primary goal of this research was to synthesize a nanocomposite from a native biomass‐derived material for the effective removal of malachite green (MG) dye from wastewater. The zirconium oxide‐incorporated sugarcane bagasse biochar (ZrO 2 –SBB NCs) nanocomposites were synthesized using an ultrasonication‐assisted method and employed as an adsorbent for the removal of MG dye from aqueous solutions. The surface characteristics and physicochemical properties of the synthesized nanocomposite were evaluated using FE‐SEM, FTIR, XRD, BET surface area, and zeta potential analyses. FTIR and XRD analyses were also performed to characterize the biochar before and after MG adsorption. Batch adsorption experiments were conducted to investigate the effects of temperature, pH, contact time, and adsorbent dosage on MG removal efficiency. The pseudo‐second‐order kinetic model provided the best fit to the adsorption kinetics, with a correlation coefficient ( R 2 ) of 0.99, while the Freundlich isotherm model best described the equilibrium adsorption behavior, with an R 2 value of 0.99. Thermodynamic analysis indicated that the adsorption of MG onto the ZrO 2 –SBB nanocomposite was spontaneous and endothermic. Furthermore, the nanocomposites exhibited good reusability over five consecutive adsorption–desorption cycles.