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Coal bottom ash (CBA) waste generated from coal-based industries has been increasing at an alarming rate causing huge problems in its recycling and disposal process. On the other hand, CBA is potentially used as raw material in zeolite manufactures due to its high SiO2 and Al2O3 contents. We report the conversion of CBA into zeolites-like material via a low temperature method of 90°C for 24 h using NaOH solution. The synthetic zeolite was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and BET surface area measurement. The study of its adsorption-desorption properties was also conducted using ammonium solution. FTIR spectra confirmed characteristic zeolite peaks at 980-1170 cm-1, 740.6 cm-1, 439.7 cm-1, 559.3 cm-1 for Si-O, Al-O and Si-O-Al absorptions, respectively. XRD results indicated the formation of sodium aluminosilicate hidrate belong to the zeolite structure group at NaOH 5M ratio of 1:8. XRF results also indicated the domination of Al2O3 and SiO2 in the zeolite composition. BET analysis resulted the surface area of zeolite was 60.38 m2/g, markedly increased from the initial surface area of CBA of 0.598 m2/g. The maximum adsorption capacity for ammonium ions were 85.22 mg/g and the adsorption data fitted the Freundlich isotherm model. Meanwhile, the desorption study indicated that the ammonium leached rapidly in the first 3 h followed by a plateu in the next 71 h.