Abstract
Methylene blue dye, commonly used in various industries, poses significant risks to both human health and the environment due to its persistence, toxicity, and potential to disrupt aquatic ecosystems. Exposure can cause severe health conditions such as methemoglobinemia, while its stability and solubility allow it to persist in natural water systems, reducing oxygen levels and harming aquatic life. In this study, novel analcime/sodium magnesium aluminum silicon silicate nanocomposites (Z1 and Z2) were synthesized via a controlled hydrothermal method, where Z1 and Z2 were synthesized in the absence and presence of polyethylene glycol as a template, respectively. X-ray diffraction (XRD) analysis confirmed the formation of crystalline phases of analcime and sodium magnesium aluminum silicon silicate. The average crystallite size of the Z1 nanocomposite is 75.30 nm, whereas the Z2 nanocomposite exhibits a smaller average crystallite size of 60.27 nm due to the template effect. Field emission scanning electron microscopy (FE-SEM) revealed that Z2 exhibited more uniform and well-dispersed particles compared to Z1. Energy-dispersive X-ray spectroscopy (EDX) confirmed the elemental composition, showing higher sodium content and optimized incorporation of aluminum and silicon in Z2. High-resolution transmission electron microscopy (HR-TEM) demonstrated that Z2 had well-defined spherical particles, indicating improved structural control. The maximum adsorption capacities were 230.95 mg/g for Z1 and 290.69 mg/g for Z2. The adsorption process was exothermic, spontaneous, and chemical in nature, following the pseudo-second-order kinetic model and Langmuir isotherm, confirming monolayer adsorption on homogeneous surfaces.