EVALUATION OF HEAVY METALS ADSORPTION (As, Tl, Se AND Sb) USING DIFFERENT MICROPOROUS MATERIALS (ZEOLITE AND MOF)

The growing population is increasing the demand for clean, potable water, making effective wastewater treatment essential. Water pollution, particularly from industrial discharges and agricultural runoff, introduces heavy metals such as arsenic, lead, and cadmium, which are harmful in large amounts. 1-4. This project aims to develop innovative, cost-effective and sustainable organic-inorganic composite materials for removing selected heavy metals from polluted water, specifically designed to remove targeted heavy metals from contaminated water. This study focuses on evaluating the adsorption capacities of various microporous materials for four particular heavy metals: arsenic (As V), thallium (Tl I), selenium (Se IV), and antimony (Sb V). The research involves the assessment of natural and synthetic zeolites (i.e. clinoptilolite, 13X, ferrierite, beta and L zeolites), as well as a Metal-Organic Framework (ZIF-8), to determine the most effective adsorbents for these contaminants. Under same laboratory conditions (pH, stirring time, temperature, adsorbent material concentration, and metal concentration), all tested materials exhibited adsorption capabilities, as confirmed by thermal analysis and X-Ray Diffraction (XRD). Inductively Coupled Plasma Mass Spectrometry (ICP-MS) of the remaining liquid after the adsorption tests allows for the identification of the most effective materials for each specific metal. Notably, calcined Beta-25 (Zeolyst - CP814E) and calcined Ferrierite zeolites (Zeolyst - CP914C) demonstrated significant efficiency in removing all four metals. ZIF-8 was also examined, as it possesses a high surface area (1300–1800 m²/g) and has been reported to exhibit an adsorption capacity of approximately 65% for arsenic and 25% for selenium, with lower efficiencies for thallium and antimony. Future investigations will concentrate on a more comprehensive analysis of the most effective materials by manipulating variables such as pH, temperature, solid-to-liquid ratio, and metal concentration. The final phase of this research will involve testing these materials in real fluid conditions to evaluate the competitive adsorption of different ions. References: 1 Shah, M. P. Chemistry in the Environment Series No. 5 Biological Treatment of Industrial Wastewater Edited. 2022. 2 Mohod, C. V; Dhote, J.; Int J Innov Res Sci Eng Technol 2013, 2(7), 2992-2996. 3 Pasti, L.; Sarti, E.; Cavazzini, A.; Marchetti, N.; Dondi, F.; & Martucci, A. J SEP SCI 2013, 36(9–10), 1604–1611. 4 Jian, M.; Liu, B.; Zhang, G.; Liu, R.; & Zhang, X. Colloids Surf. A Physicochem. Eng. Asp., 2015 465, 67–76.