MODIFICATION OF NATURAL ZEOLITES AND EVALUATION OF THEIR ADSORPTION AND ION-EXCHANGE EFFICIENCY FOR AMMONIUM REMOVAL FROM WATER

Ammonium contamination in water bodies poses significant environmental and public health concerns due to its contribution to eutrophication and deterioration of water quality. This study investigates the modification of natural zeolites and evaluates their adsorption and ion-exchange efficiency for ammonium removal from aqueous solutions. Natural zeolite samples were chemically modified to enhance their surface properties and cation-exchange capacity. The structural and physicochemical characteristics of the raw and modified materials were analyzed using various characterization techniques. Batch adsorption experiments were conducted to assess the effects of contact time, initial ammonium concentration, solution pH, and adsorbent dosage on removal performance. The modified zeolites exhibited significantly improved ammonium uptake compared with the untreated material, indicating the positive effect of surface modification on adsorption behavior. Adsorption equilibrium was achieved within a relatively short period, and the removal efficiency increased under optimized experimental conditions. Equilibrium and kinetic data were interpreted using commonly applied adsorption models to elucidate the mechanisms governing ammonium uptake. The results demonstrate that modified natural zeolites are efficient, environmentally friendly, and economically attractive adsorbents for ammonium removal from water, highlighting their potential application in sustainable water and wastewater treatment technologies.