Study on the performance of simultaneous desulfurization and denitrification of Fe3O4-TiO2 composites

With Fe3O4 as the carrier, tetrabutyl titanate as precursor, the TiO2 was wrapped on the surface of Fe3O4 by hydrothermal method to synthesize the Fe3O4-TiO2 composite. X-ray powder diffraction (XRD), Transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) analysis showed that the nano TiO2 formed a better coating layer on the surface of Fe3O4 particles. In the experiment, the simulation of the SO2 and NO of the industrial coal-fired flue gas was tested respectively by Fe3O4, TiO2 and x%Fe3O4-TiO2 (x% represents the mass fraction of Fe3O4 of the total material). The results showed that the activities of TiO2 and Fe3O4-TiO2 were good, and both of them had good removal effect on SO2 and NOx. TiO2 was wrapped on Fe3O4, which formed a special package structure, the surface layer of nano TiO2 and Fe3O4 carrier can promote each other, the performance of simultaneous desulfurization and denitrification can be further improved. Fe3O4-TiO2 composites with different ratio were tested at 100 degrees C; 10% Fe3O4-TiO2 had high reaction performance; the removal effect gradually decreased with the increase of Fe3O4 content. The performance of 10%Fe3O4-TiO2 composite on simultaneous desulfurization and denitrification at 100 degrees C, 150 degrees C, 200 degrees C was in descending order. At the temperature of 100 degrees C, the removal effect of 10% Fe3O4-TiO2 on SO2 and NOx can be maintained at 100% and 50% respectively, and it was not until after 64 min the NOx was close to penetrate. The addition of H2O enhanced the SO2 adsorption; and the NO adsorption capacity decreased with the increase of the H2O content. NOx and SO2 were adsorbed on the surface of the composite material by physical and chemical adsorption, the products were sulfate and nitrate according to the results of the characterization. (C) 2016 Elsevier B.V. All rights reserved.