Simultaneous catalytic oxidation of Hg0 and AsH3 over Fe-Ce co-doped TiO2 catalyst under low temperature and reducing atmosphere.

Abstract

The Fe-Ce bimetal oxide-doped titanium dioxide composite was synthesized by the sol-gel method and the performance of the catalyst was investigated for the removal of Hg0 and AsH3 from yellow phosphorus flue gas under different conditions. Brunauer-Emmett-Teller (BET) analysis, high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were used to characterize the crystal structure and morphology of the structure, and the mechanisms for removing Hg0 and AsH3 from flue gas by catalytic oxidation were deduced. The results showed that the optimal calcination temperature of the Fe5Ce5Ti catalyst was 500 °C, and the optimal pH of the sol was 6. Under these conditions, the penetration adsorption capacity of the Fe5Ce5Ti catalyst for the removal of AsH3 and Hg0 was 385.5 mg g-1 and 2.178 mg g-1, respectively. According to characterization analysis, Fe and Ce are the main active components in the removal of Hg0 and AsH3, and the mixed oxides of Fe and Ce have a synergistic effect on the surface of the mixed oxide-doped catalyst, which can improve the dispersion of the active component on the surface of the catalyst, and then improve the removal efficiency of Hg0 and AsH3.