Synthesis, Characterization and Photocatalytic Activity of MnO2/Al2O3/Fe2O3 Nanocomposite For Phenol Degradation

Abstract

Photocatalysis has become a fast wastewater treatment technology. Herein; ternary mixed oxide catalyst, phenol pollutant and visible light were used. The new MnO2/Al2O3/Fe2O3 nanocomposite was synthesized by sol-gel method using Fe(NO3)3.9H2O, Al(NO3)3.9H2O, MnO2, 1-C4H9OH and 68 % HNO3 precursors in aqueous solution and characterized by XRD, UV-VIS, FAAS and FTIR instruments. The crystal size and the bang gap energy of MnO2/Al2O3/Fe2O3 nanocomposite were found to be 20 nm and 2.25 eV, respectively. The photocatalytic activity of MnO2/Al2O3/Fe2O3 nanocomposite was tested under varies operational parameters. The optimum operational parameters were found to be 10 pH, 50 mg.L-1 C6H5OH, 20 mg.L-1MnO2/Al2O3/Fe2O3 nanocomposite, visible light presence and 3 hr irradiation time. At optimum operational parameters phenol degradation efficiency was found to be 93.1 %. The kinetic studies indicated that the pseudo first order rate constant was 01.62x10-2 min-1for the phe-vis-cat tests. Finally, the phenol degradation mechanisms were discussed. Keywords: Photocatalysis, MnO2/Al2O3/Fe2O3 nanocomposite, phenol pollutant, visible light and operational parameters.