Adsorption properties of low-cost synthesized nanozeolite L for efficient removal of toxic methylene blue dye from aqueous solution

Abstract

In this study, nanozeolite L was applied for the removal of toxic methylene blue dye (MB) to evaluate its feasibility as an effective adsorbent. Synthesized nanozeolite L was characterized by X­ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electronic microscopy (SEM), Brunauer–Emmett–Teller (BET), and energy-dispersive X­ray analysis (EDX) methods to determine its basic physicochemical properties. Batch adsorption studies were performed as a function of pH, adsorbent dose, contact time, initial MB concentration, and temperature. The adsorption behavior of MB was fitted better by the Langmuir isotherm than by the Freundlich isotherm, and the maximum adsorption capacity of nanozeolite L was obtained 80.64 mg g-1. The negative values of Gibbs free energy change (ΔG°) and the positive value of the standard enthalpy change (ΔH°) affirmed that the adsorption process is spontaneous and endothermic. Based on these findings, nanozeolite L, with high surface area, great adsorption capacity, and low synthetic cost, can be an effective and economical adsorbent for MB removal.

Keywords

• nanozeolite l
• hydrothermal synthesis
• methylene blue
• adsorption