Liquid-phase oxidation of naphthalene with $$\hbox {H}_{2}\hbox {O}_{2}$$ H 2 O 2 in the presence of ordered mesoporous $$\hbox {V-}m\hbox {-Al}_{2}\hbox {O}_{3}$$ V- m -Al 2 O 3 catalysts

Abstract

The ordered mesoporous $$\hbox {V-}m\hbox {-Al}_{2}\hbox {O}_{3}$$ catalysts were successfully synthesized via a facile one-pot evaporation-induced self-assembly (EISA) strategy and applied in the liquid-phase oxidation of naphthalene with hydrogen peroxide in the presence of ascorbic acid as a reductant. The physicochemical properties of the catalysts were investigated using various techniques, like XRD, $$\hbox {N}_{2}$$ sorption, UV-Vis spectra, Raman spectroscopy, XPS, XRF and TEM. Small-angle XRD, $$\hbox {N}_{2}$$ sorption and TEM results show that mesoporous $$\hbox {V-}m\hbox {-Al}_{2}\hbox {O}_{3}$$ catalysts possess a highly ordered mesostructure with large surface areas and narrow pore-size distributions. High-angle XRD, UV-Vis spectra and Raman spectroscopy results indicate that $$\hbox {VO}x$$ species were homogeneously incorporated in the matrix of mesoporous $$\hbox {Al}_{2}\hbox {O}_{3}$$ .The catalytic performance in the liquid oxidation of naphthalene with $$\hbox {H}_{2}\hbox {O}_{2}$$ over $$8\hbox {V-}m\hbox {-Al}_{2}\hbox {O}_{3}$$ catalyst (naphthalene conversion 45.4% and phthalic anhydride selectivity 61.0%) was higher than other catalysts. The vanadium species incorporated in the $$8\hbox {V-}m\hbox {-Al}_{2}\hbox {O}_{3}$$ sample were stable, and its catalytic stability was kept well even after repeated use for 5 times, which indicates a green and economical pathway for naphthalene degradation. SYNOPSIS In the presence of hydrogen peroxide as oxidant and ascorbic acid as reductant, ordered mesoporous $$\hbox {V-}m\hbox {-Al}_{2}\hbox {O}_{3}$$ catalysts were synthesized via a facile one-pot evaporation-induced self-assembly method and successfully applied to the liquid-phase oxidation of naphthalene.