Annisaa Siti Zulaicha, Buhani Buhani, Miranda Sari, Suharso Suharso
Activated carbon from oil palm shells was synthesized and characterized through physical (CAF) and physical-chemical (CAFK) activation at 700 °C using H3PO4 as the activator. Charcoal was analyzed using XRD for crystallinity, SEM-EDX for surface morphology and elemental composition, and BET surface area to determine adsorption-desorption isotherm pattern and surface area. This study investigated the adsorption of Cd(II) onto Activated Carbon (AC). It aimed to determine the optimal dose and pH, as well as the kinetic model and adsorption isotherm pattern. The optimal adsorption conditions for Cd(II) were a 100 mg dose, pH 6, and a 120 min contact time. The adsorption kinetics for both CAF and CAFK followed a pseudo-second-order model. The Cd(II) adsorption isotherm on both CAF and CAFK fitted the Freundlich model with an R2 of 0.997. The ideal Cd(II) concentration for both adsorbents was 300 mg/L. The study suggests that unmodified AC (CAF and CAFK) is an effective adsorbent for removing Cd(II) cations from water, with the adsorption capacity further enhanced by increasing the pH of the solution. © 2026 Author(s).
Faculty of Sciences, Sumatera Institute of Technology, Jl. Terusan Ryacudu, Way Huwi, Jati Agung, South Lampung, 35365, Indonesia; Department of Chemistry, Faculty of Mathematics and Natural Sciences, University of Lampung, Jl. Sumantri Brojonegoro No 1, Bandar Lampung, 35141, Indonesia