Adsorption of Nickel Ii Ion on Chemically Activated Rice Husk

ABSTRACT The contamination of water resources by heavy metals such as nickel presents a serious threat to public health and environmental sustainability. This study investigates the efficiency of chemically activated rice husk, an agricultural waste product, as a low-cost and eco-friendly adsorbent for the removal of Nickel(II) ions from aqueous solutions. The rice husk was pre-treated, carbonized at 450°C, and chemically activated using 5% sodium carbonate. Characterization of the activated carbon using Fourier Transform Infrared Spectroscopy (FTIR) revealed the presence of functional groups such as hydroxyl (-OH), carbonyl (C=O), alkane (C-H), and aromatic (C=C), which contribute to its adsorption capacity. Batch adsorption experiments were carried out under controlled conditions, examining the effects of adsorbent dosage, initial metal concentration, and contact time. The results showed that nickel removal efficiency increased with increasing adsorbent dosage and contact time, reaching an optimal removal efficiency of 99.93% at g dosage and 60 minutes. Additionally, increasing the initial concentration of nickel enhanced removal efficiency until equilibrium was reached, indicating saturation of adsorption sites. These findings demonstrate that chemically activated rice husk is a highly effective, sustainable, and economical adsorbent for heavy metal removal from wastewater, providing a promising solution for environmental remediation.