Kinetic Pathways for Uranium Adsorption from Contaminated Wastewater Using Activated Carbon Derived from Corn Cob as a Biosorbent

With the continuous development of the nuclear industry, the amount of uranium containing wastewater discharged from the production process is increasing, which poses a great threat to the environment and human health. Therefore, it is an urgent task to find safe, environmentally friendly and efficient water treatment agents. This study evaluated the kinetic behavior and adsorption performance of corncobs-derived activated carbon for uranium removal from water. The activated carbon was produced through pyrolysis and characterized using ESEM (Environmental scanning electron microscopy ) , EDX (Energy-dispersive X-ray spectroscopy), and FTIR (Fourier transform infrared spectroscopy) to analyze its structural properties. Batch kinetic experiments investigated the influence of pH, contact time, temperature, particle size, and adsorbent dosage on uranium adsorption. Under optimized conditions, the adsorbent achieved 88.3% uranium removal with a maximum capacity of 7.27 mg/g. Kinetic analysis revealed that the adsorption process followed pseudo-first-order kinetics, while equilibrium data aligned with the Langmuir isotherm model. The study also noted a correlation between uranium removal and organic pollutant degradation, as indicated by decreasing COD (Chemical oxygen demand) and BOD (Biological oxygen demand) levels initially. However, beyond 60% uranium removal, COD and BOD values rose, suggesting the need to optimize contact time and dosage for kinetic efficiency. Elution with 1M HCl recovered 78.5% of uranium, demonstrating the adsorbent’s reusability. These findings highlight the potential of agricultural waste-based adsorbents for kinetically controlled heavy metal and organic pollutant remediation Keywords: Activated carbon, corn-cobs waste; adsorption; uranium removal; Kinetics.