Synthesis And Application Of Porous Material Loading Of Iron Oxide

With the rapid growth of economy, dye wastewater from dye production and textile and dyeing industry has become the main source of water pollution. In order to solve the serious pollution problems caused by the dye wastewater effectively, it is of great significance to develop a fast and efficient dye wastewater treatment technology for the protection of water resources and water pollution governance. Fenton reaction as one of advanced oxidation technology has the advantages of oxidation ability strong and high efficiency. It has been widely utilized for the treatment of high-concentration non-readily degradable organic wastewater.A novel Fe2O3/HPS hybrid catalyst was synthesized by sol-gel and wetness impregnation methods. Bimodal mesoporous and macroporous silica has the multiple benefits arising from the different pore-size regimes. The hierarchical pore structrue not only provides abundant space to load catalytic sites but also increases the internal diffusion and mass transfer in the pores. The obtained Fe2O3/HPS hybrids were characterized by SEM, EDS, XRD, XPS, N2adsorption-desorption isotherms, DFT and Hg porosimetry. The catalytic activity of the Fe2O3/HPS was evaluated by the photo-Fenton degradation of azo-dye Orange H. More than90%of dye could be degraded just under vis-light irradiation. Compared with other iron oxide, such as the commercial or the laboratory synthesized hematite, the Fe2O3/HPS exhibited the higher performance for dye degradation. The effects of pH, H2O2concentration, additive (hydroxylamine hydrochloride), leaching and stability tests were studied. The Fe2O3/HPS worked well in a wider pH range (2.5-8.5) than common homogeneous Fenton catalyst. Degradation kinetics for the photocatalytic degradation of dye wastewater was investigated. The kinetics equations and parameters were obtained. In addition, this new type of catalyst was very stable in physical and chemical properties and could be repeatedly used.Furthermore, a novel composite catalyst Fe2O3-MCM41was fabricated by co-polymerization method. The pore sizes of mesoporous materials were regulated by adding a certain amount of1,3,5-trimethylbenzene (TMB). A hybrid material, Fc-MCM41, was prepared by covalently anchoring ferrocene onto the mesoporous silica material MCM41. After the process of simple oxidation, FeO3-loaded mesoporous material (Fe2O3-MCM41) was obtained. The catalytic property of Fe2O3-MCM41used as the heterogeneous Fenton catalyst for photo-Fenton degradation of dye wastewater was investigated. Fe2O3-MCM41exhibited high catalytic activity for degrade several dyes under visible light irradiation. The removal rate of the dyes could reach93.3%(neutral red) and98.5%(melhylene blue). Moreover, after several recycles, the Fe2O3-MCM41could still convey a considerable catalytic ability and could be easily separated and recycled.These two novel heterogeneous Fenton catalysts could overcome many shortcomings of*traditional homogeneous Fenton system, such as the narrow range of pH. unrecyclability and liability to the secondary pollution. Therefore, they had great practical application potential for the degradation of many organic pollutants in practice.