In this study, the synthesis of template free zeolite Y and its recrystallization to two types of pure zeolite P and analcime in the presence of the amino acid d‐methionine as structure‐directing agent were investigated. The recrystallization occurred solely when specific heating cycles were applyed. A completely crystallized phase of zeolite Y for the mixture of zeolite P and analcime was observed in the presence of d‐methionine at a concentration of 0.015 m. The effect of different Si/Al ratios (2.3–9.3), crystallization temperatures (40–160 °C), and crystallization times (28–96 hours) on the achievement of two different zeolite types were studied as well. Pure zeolite P was obtained during conventional heating to 100 °C for 42 hours, whereas pure analcime zeolite was achieved by heating the mixture to 160 °C for 96 hours. The products were characterized by X‐ray diffraction, scanning electron microscopy, and IR spectroscopy.

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In this study, a novel approach for the synthesis of nano‐sodalite zeolite crystals is explored. Synthesized nanocrystals were then characterized successfully via various techniques such as X‐ray diffraction (XRD), Fourier transform infrared (FT‐IR), scanning electronic microscopy (SEM), and Brunauer–Emmett–Teller (BET), and energy‐dispersive X‐ray analysis (EDX). Then, the performance of nano‐sodalite zeolite was evaluated for its potential in the adsorptive removal of cationic crystal violet (CV) dye. The effects of various experimental parameters, such as pH, adsorbent dosage, contact time, initial dye concentration, and temperature, were investigated in batch mode. Also, the adsorption isotherm, kinetic, and thermodynamic parameters were studied. The equilibrium sorption data were fitted better by the Freundlich isotherm than by the Langmuir isotherm. The kinetic adsorption data obeyed the Lagergren pseudo‐second order model. Thermodynamic parameters analysis revealed that the adsorption of CV from an aqueous solution by nano‐sodalite zeolite was a spontaneous and endothermic process. The results indicated that nano‐sodalite zeolite could be applied as a promising adsorbent for the efficient removal of CV from aqueous solutions.

Zeolites are effective adsorbents to remove heavy metals from aqueous solutions. To investigate the role of the template on enhancing the ability of zeolites to absorb metals, methionine amino acid was introduced to zeolite synthesis gel to produce a modified analcime zeolite. Afterwards, adsorption of Cu(II) and Ni(II) cations on templatefree analcime and methionine-templated analcime were studied and the experimental data were fitted with Freundlich and Langmuir equations in order to obtain the sorption parameters. Batch experiments were carried out to evaluate Cu(II) and Ni(II) adsorption at different pH values, heavy metals concentrations, and removal intervals. The results showed that the metal removal efficiency was strongly dependent on the pH of the solutions. The analcime zeolites absorbed Cu(II) more readily than Ni(II). Furthermore, methionine-templated analcime exhibited a higher potential for heavy metal removal than the template-free zeolite. Raman spectra indicated that the presence of a methionine template during analcime zeolite synthesis could create a complex structure of Cu−S (methionine)/zeolite and Ni−S (methionine)/zeolite. Thus introducing a sulphur-containing template such as methionine may give further possibilities to improve the metal removal efficiency of zeolites.