Facile Hydrothermal Fabrication of Analcime and Zeolite X for Efficient Removal of Cd(II) Ions From Aqueous Media and Polluted Water

In this paper, analcime and zeolite X were fabricated using the hydrothermal method in the presence of L-alanine and glycine as organic structure-directing agents, respectively. The XRD confirmed that the average crystallite size of zeolite X and analcime products is 94.85 and 146.06 nm, respectively. Also, the FE-SEM confirmed that the zeolite X composed of an octahedron and cubic shapes with an average size of ca. 2.78 µm. Besides, the analcime composed of droxtal shapes with an average size of ca. 9.50 µm. Vibrations of adsorbed water, aluminol, silanol, Si–O–Si, and Si–O–Al groups were obtained using the FT-IR spectrophotometer. Moreover, the fabricated products were utilized for the removal of Cd(II) ions from aqueous media and wastewater which was collected from an electroplating factory in the 10th of Ramadan City, Egypt. The pseudo-second-order model and Langmuir isotherm were the best fittings for the experimental results. The removal of Cd(II) ions was exothermic because the values of ∆H^o in the case of zeolite X and analcime were − 49.859 and -61.647 kJ/mol, respectively. Also, the removal of Cd(II) ions was spontaneous because the values of ΔG^o in the case of zeolite X and analcime were − 101.678 and − 119.669 kJ/mol at 298 K, respectively. Besides, the maximum adsorption capacity of analcime and zeolite X was 139.278 and 62.814 mg/g, respectively. Moreover, the fabricated samples are reusable, effective, stable, and can be utilized over and over without surrendering their efficiency towards Cd(II) ions in aqueous solutions and wastewater.