Synthesis and Adsorption Performance of Magnetic Geopolymer Composites for the Removal of Manganese from Groundwater

The provision of safe drinking water is one of the greatest challenges of our time. Drinking water resources often contain various components, such as metal ions, natural organic substances, and others. Manganese is an essential metal with a vital function in living organisms; however, the presence of manganese ions in water in high concentrations (> 50 μg/L) has a negative impact on health. An effective method for removing manganese ions from water is adsorption, using various materials as adsorbents. This study investigated the efficiency of applying innovative biofunctionalized magnetic geopolymer composites for the demanganization of groundwater. The
demanganization of groundwater from the Novi Sad area, which contains a high concentration of Mn ions (400 μg/L), was carried out using biofunctionalized magnetic geopolymer composites based on kaolin. These composites were functionalized by adding tangerine peel extract. The synthesized composites were characterized by XRD, FTIR, TG, DSC, and SEM/EDS methods and subsequently used as adsorbents for the removal of Mn ions. The removal of Mn ions was carried out with 5 g/L of the composite for 1 hour. After 10 minutes of the process, a high efficiency of Mn ion removal was achieved (91%), reducing the Mn content in the water to 35 μg/L. With increasing reaction time, there is no significant increase in process efficiency (up to 95%). It can therefore be concluded that the composite materials used have a high potential for use as adsorbents for water demanganization.