Synthesis of the novel CuAl2O4–Al2O3–SiO2 nanocomposites for the removal of pollutant dye and antibacterial applications

Abstract

CuAl2O4–Al2O3–SiO2 nanocomposites with different amounts of CuAl2O4 (40, 50, 60 and 70 wt. %) were synthesized by the sol–gel method and characterized by XRD, FTIR, FESEM, EDS and TEM analyses. The nanocomposites were applied for removal of methylene blue (MB) as a cationic dye from aqueous solution. The relation between removal percentages with variables such as adsorbent dosage (0.01, 0.03 and 0.05 g), adsorbent type (0, 30, 50, 70 and 100 wt. % related to CuAl2O3 in CuAl2O4–Al2O3–SiO2), pH (4, 7 and 10) and initial MB concentration (5, 10, 20 and 30 mg/L) was investigated. The maximum removal efficiency of MB was 96 wt. % in the optimized conditions (0.01 g of adsorbent, 50 wt. % of CuAl2O3, pH = 10 and MB = 10 mg/L). Moreover, an obvious decrease in the amount of Escherichia coli in a medium was observed by the addition of the title nanocomposite to the medium indicating its beneficial antibacterial activity.