Microwave modified sugar cane bagasse cellulose as an eco-friendly biosorbent for eliminating As(V) from aqueous...

This work explores the potential of microwave assisted urea modified sugarcane bagasse (UMSCB) as an effective, environment-friendly biosorbent for removing As(V) from an aqueous medium. The synthesized biomaterial was characterized by FTIR analysis that showed the existence of various carboxyl, hydroxyl, and carbonyl functional groups; and SEM analysis of UMSCB showed much higher roughness before the As(V) adsorption of 40.78; indicating that As(V) intricately gets adsorbed onto surface of UMSCB. Batch adsorption experiments demonstrated a removal efficiency of approximately 95 % within 30 min at pH 5. However, UMSCB follows pseudo-second-order kinetics and chemisorption mechanism for removal of As(V). The intra-particle diffusion model indicated that more than one step influences the rate-limiting step. Adsorption equilibrium data shows that the Langmuir model provided the best fit, as determined by correlation coefficient (R²) and chi-square (χ²). Notably, the adsorption capacity (q_e) of unmodified sugarcane bagasse (SCB) significantly increased from 4.8 mg/g to 52.8 mg/g upon microwave-assisted urea modification, demonstrating the substantial enhancement in As(V) uptake. Thermodynamic indicators indicated that the biosorption is spontaneous, endothermic, and feasible. The high adsorption efficiency, ease of regeneration, and potential for large-scale application highlight UMSCB as a promising solution for As(V) removal from wastewater.