NATURAL ZEOLITE RECRYSTALLIZATION AS PB(II) AND CU(II) ION ADSORBENT

• Main Author: Rona Nadhifah, Afi
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/62831
• Institution: Institut Teknologi Bandung

Heavy metal pollution has become a serious issue worldwide due to the increasing industrial activity in the world. . The objectives of this study were to increase the crystallinity of natural zeolite by hydrothermal method as an adsorbent for the adsorption of Pb(II) and Cu(II) ions. Zeolite were characterized by several techniques: Fourier transform Infrared Spectroscopy (FTIR), Scanning Electrone Microscopy (SEM) coupled with Energi Dispersive Spectroscopy (EDS), and X-Ray Diffractometer (XRD). Parameters such as pH, initial concentration of solution, contact time, and temperature are optimized. The FTIR characterization showed the peak of the T-O-T (T = Si and Al) bond strain at wave number at 500-850 cm-1 and 1000-1250 cm-1. The peak of the hydroxyl group showed at wave number 3500 - 3600 cm-1. The results of XRD characterization showed that the modification process succeeded in increasing the crystallity of the zeolite to 70.50 %. The adsorption process of Pb(II) and Cu(II) ions by zeolite fit well to the the Langmuir isotherm model with Qmax 145.0867 mg/g for Pb(II) and 92.7690 mg/g for Cu(II). These indicated that zeolite had potential to adsorb Pb(II) and Cu(II). The result also suggested that the adsorption capacity was affected by the diameter of hydrated, electronegativity of heavy metals ion, and amount of negative charge. Kinetic studies show the adsorption process runs in three steps : film diffusion, internal diffusion, and microporo diffusion Calculation of thermodynamic parameters such as enthalpy, entrophy and Gibbs free energy showed the process was endothermic with ?H = 72.79 kJ/mol and ?S = 291.73 J/K mol and the adsorption process of Cu(II) and Pb(II) ions takes place spontaneously