sustainable production of activated carbon from corn cob biomass for efficient dye adsorption and regeneration in alkaline conditions

Water pollution remains a critical global concern, particularly due to the persistence of organic contaminants in aquatic environments. in this study, natural biomass waste, specifically corncobs, was utilized as a precursor to synthesize corn cob-derived activated carbon (ccac) through a simple carbonization-activation process. the physicochemical and morphological studies of activated carbon were well described by scanning electron microscopy (sem), and transmission electron microscopy (tem). the adsorption capacity demonstrated was excellent, with 99.52% efficiency and 88.88% removal efficiency for methyl red (mr) and methyl orange (mo), respectively. to assess the reusability of the material, regeneration studies were conducted using three different eluents: distilled water, 0.1 m hydrochloric acid (hcl), and 0.1 m sodium hydroxide (naoh). among these, alkaline regeneration using naoh solution proved to be the most effective, restoring the adsorbent’s structure and maintaining its active sites for dye binding. after five consecutive adsorption-desorption cycles, the ccac regenerated in an alkaline medium retained a high removal efficiency of 90.11% for mr dye and 76.33% for mo dye, indicating its strong stability and excellent recyclability. this demonstrates that ccac can serve as a low-cost, high-performance, and regenerable adsorbent for wastewater treatment, while promoting the high-value utilization of agricultural waste.