Tailored novel nanocomposites for advanced elimination of methylene blue dye from water

Abstract

Novel SrCO 3 /CuO/MgO/C (Abbreviated as CSM600) and SrCO 3 /CuO/MgO/Sr 2 CuO 2 CO 3 /Cu 2 SrO 3 /SrCuO 2 /C (Abbreviated as CSM800) multiphase nanocomposites were successfully synthesized through a Pechini sol–gel route followed by calcination at 600 and 800 °C. Structural analyses confirmed temperature-dependent phase evolution and an increase in crystallite size from 64.84 nm for CSM600 to 75.69 nm for CSM800. The optimum adsorption conditions were achieved at pH 10 and 298 K, with equilibrium times of 60 min for CSM600 and 80 min for CSM800. The synthesized materials exhibited high performance for methylene blue removal from aqueous media, with maximum adsorption capacities of 446.43 mg/g for CSM600 and 303.03 mg/g for CSM800. Adsorption was found to be spontaneous, exothermic, and predominantly physical in nature. Kinetic and equilibrium studies showed that the adsorption process follows the pseudo-first-order model and fits the Langmuir isotherm well. In addition, both nanocomposites displayed high regeneration efficiency, stable reusability over repeated cycles, and effective applicability in wastewater treatment. These findings demonstrate that the prepared multiphase nanocomposites are promising adsorbents for efficient dye remediation from water and wastewater.