Catalytic activity of Fe/SBA-15 for ozonation of dimethyl phthalate in aqueous solution

Abstract

The catalytic activity of iron-loaded SBA-15 (Fe/SBA-15) for ozonation of dimethyl phthalate (DMP) in aqueous solution was investigated. SBA-15 was synthesized by a hydrothermal method and Fe/SBA-15 was prepared by an incipient wetness impregnation method. The materials were characterized by a low and wide angle X-ray powder diffraction (XRD), N2 adsorption–desorption, and atomic absorption spectrometer (AAS). Under the chosen conditions (50mgh−1 ozone dosage, 10mgl−1 DMP solution and 0.20gl−1 catalyst dosage), Fe/SBA-15/O3 process obviously improved DMP and total organic carbon (TOC) removal efficiency due to the generation of hydroxyl radical (HO), which was approved by tert-butanol (TBA). The mineralization of DMP followed an apparent first-order kinetics. The rate constant in Fe/SBA-15/O3 was 0.0058min−1, 3.9 times higher than that of O3 alone, 3.4 and 1.9 times higher than those of SBA-15/O3 and Fe2O3/O3 processes respectively. The iron content, reaction temperature and initial pH of DMP solution played important roles in Fe/SBA-15/O3 process, while chloride ion exhibited the slight influence. The synergetic effect between O3 and Fe/SBA-15 adsorption illustrates that Fe/SBA-15 is a promising catalyst for ozonation process.