Elemental mercury removal by CeO2/TiO2-PILCs under simulated coal-fired flue gas

CeO2/TiO2-PILCs with different Ce loading were synthesized by an impregnation method for Hg-0 removal in flue gas considering the effect of various flue gas compositions. Nitrogen adsorption-desorption, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectrometer were employed for material characterization. The mechanisms of the effect of gas compositions on Hg-0 oxidation were discovered in detail in this paper. The results demonstrated that 15% Ce/Ti-PILC has the best Hg-0 oxidation efficiency at 300 degrees C under N-2 + O-2 due to the redox switch of Ce4+/Ce3+. The presence of SO2 in flue gas could restrain the oxidation activity by generating SO42- on 15% Ce/Ti-PILC surface. Hg oxidation was enhanced by HCI in flue gas because of the Deacon mechanism. NO2 was detected on the catalyst surface when NO was introduced into the in flue gas, which was responsible for the promotional effect of NO on Hg oxidation. The prohibitive influence of NH3 and H2O on Hg oxidation was obvious, which was due to the competitive adsorption. CeO2/TiO2-PILCs was demonstrated to be a potential catalysts for Hg oxidation in flue gas. (C) 2016 Elsevier B.V. All rights reserved.