Assessment of the Efficiency of Methylene Blue Removal from Aqueous Solutions Using Iron Magnetic Nanoparticles Immobilized on Clinoptilolite Zeolite

High amounts of dyes in receiving waters are dangerous to the ecosystem due to their specific properties, such as high alkalinity, high organic compound content, and robust structure. The present article aims to investigate the efficiency of the Fe₃O₄/zeolite process in removing methylene blue dye (MB) from aqueous solutions, as well as to optimize the factors influencing the efficiency of removal. Initially, a Fe₃O₄/zeolite nanocomposite was prepared and characterized using Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) techniques. The impact of various parameters such as pH of the aqueous solution, nanocomposite dosage, contact time, and initial dye concentration on the adsorption efficiency was systematically investigated. FTIR shows presence of iron disrupts the hydrogen bonds in the zeolite structure. Additionally, SEM analysis reveals the pronounced microporosity of the Fe₃O₄/zeolite nanocomposite. Optimal conditions were determined to be a pH of 9.0, an adsorbent dosage of 0.75 g/L, a contact time of 45 min, and a methylene blue concentration of 50 mg/L, resulting in a removal efficiency of 96.92%. Adsorption isotherm and kinetic studies revealed that the adsorption process of methylene blue followed the Freundlich isotherm (R² > 0.984) and pseudo-second-order kinetic models (R² > 0.9958), respectively. The qm (sorption capacity) of the Fe₃O₄/zeolite nanocomposite was 113.64 mg/g. Furthermore, the reusability of the adsorbent was assessed through five consecutive experiments, demonstrating only a marginal decrease (approximately 7.9%) in methylene blue removal efficiency. These findings underscore the potential of the magnetic nanocomposite based on zeolite as a highly effective adsorbent for methylene blue removal applications.