Preparation and Characterization of Rice Husk-Derived Activated Carbon for Efficient Removal of Rhodamine B from Aqueous Solution

Abstract

This study investigated the adsorption efficiency of activated carbon prepared from rice husk (TRH-Na) for removing Rhodamine B (RhB) from aqueous solution. The effects of initial concentration, contact time, adsorbent dosage, pH and temperature on adsorption capacity were optimized. The TRH-Na was characterized using bulk density, moisture content, ash content, FTIR and SEM/EDX analyses. The optimal adsorption conditions were determined, and the adsorption data fitted well to the Langmuir and Temkin isotherms, which indicates monolayer adsorption onto the surface of the TRH-Na. The pseudo-second-order kinetic model best described the sorption kinetics. Thermodynamic analysis revealed negative ΔG values, indicating a feasible and spontaneous adsorption process, and negative ΔH values, confirming an exothermic process. These findings demonstrate the potential of TRH-Na as an effective adsorbent for removing RhB from aqueous solution