CE3+ METAL ION ADSORBENT BASED ON ALGINATE/POLYVINYL ALCOHOL NETWORK BY

• Main Author: Mila Haili, Hulqi
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/79572
• Institution: Institut Teknologi Bandung

Cerium is one of the rare earth elements (REE) widely used in the development of current high-tech technologies. The high demand for cerium raises concerns about the depletion of primary REE reserves in the future, correlating with the generation of waste that may enter aquatic environments. Therefore, recycling and recovering REE from secondary sources become alternative options. Common methods for REE recovery include solvent extraction, ion exchange, filtration, and adsorption. Adsorption is often preferred due to the simplicity, efficiency, and cost- effectiveness of adsorbent production, as many adsorbent materials are abundant in nature. Alginate-PVA biosorbent, referred to as Alg/PVA (NIP), and Ce3+ IIP Alg/PVA (Ce-IIP) have been used for the adsorption of cerium ions. The NIP and Ce-IIP adsorbents were characterized using various instruments such as Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), and water absorption tests. Optimal adsorption conditions for 0.1 g of adsorbent were achieved at pH 4 with a contact time of 360 minutes (NIP) and 240 minutes (Ce-IIP). Adsorption using NIP and Ce- IIP followed the Langmuir adsorption isotherm model and pseudo-second-order kinetic model. Ce-IIP exhibited a higher maximum adsorption capacity (qmax) than NIP, with values of 45.871 mg/g and 30.845 mg/g, respectively. The cerium ion adsorption process using NIP was endothermic with a negative ?G, ?H=7.714 kJ/mol, and ?S=0.075 kJ/K mol. Meanwhile, adsorption using Ce-IIP was exothermic with a negative ?G, ?H= -9.135 kJ/mol, and ?S= 0.138 kJ/K mol. The adsorption process occurred spontaneously for both NIP and Ce-IIP.