Enhancement of Oxidation Efficiency of Elemental Mercury by CeO(2)/TiO(2) at Low Temperatures Governed by Different Mechanisms

[Image: see text] This study aims to investigate the photothermal oxidation removal of Hg(0) in simulated flue gases using photothermal catalysts at relatively low temperatures of 120–160 °C in two phases: the first phase applied the sol–gel method to prepare TiO(2) and CeO(2)/TiO(2) photothermal catalysts and characterized surface properties by specific surface area analysis, X-ray diffraction, X-ray photoelectron spectroscopy (XPS), and photoluminescence spectroscopy. The second phase investigated the effects of operating parameters on Hg(0) oxidation efficiency at lower temperatures of 100–160 °C. The operating parameters included reaction temperatures and modified concentrations of CeO(2). Experimental results indicated that TiO(2) prepared by the sol–gel method was mainly in the anatase phase. XPS analysis showed that Ce mostly existed in the form of Ce(4+). The content of surface-chemisorbed oxygen increased with the modification amount of CeO(2). Photothermal catalytic oxidation results indicated that CeO(2)/TiO(2) had a much higher oxidation efficiency of Hg(0) at 120–160 °C than neat TiO(2), which increased from 30–60 to >90%. 7%CeO(2)/TiO(2) not only had the best photothermal performance but also maintained high efficiency at a relatively higher reaction temperature of 160 °C.