Effect of CeO2 and Pt introduction on the structure and performance of Fe2O3 for Hg0 removal

Abstract

In this work, the thermal stability and catalytic activity of Fe2O3 catalyst for Hg0 oxidation were improved by the introduction of CeO2 and Pt. During high-temperature calcination at 400 °C, the mesoporous structure of Pt/CeO2/Fe2O3 remained stable, and it also retained higher specific surface area and lower average pore size than Fe2O3. The X-ray diffraction, transmission electron microscopy, and thermal gravimetric-differential scanning calorimetry results revealed that the modification of CeO2 and Pt retarded the crystallization and growth of Fe2O3 grains during high-temperature calcination, limiting Fe2O3 particles to a smaller size. Temperature-programmed desorption experiments showed that Hg0 adsorption of Pt/CeO2/Fe2O3 was promoted. In addition, X-ray photoelectron spectroscopy spectra suggested that adding CeO2 and Pt also increased the content of chemisorbed oxygen and transformed Fe2O3 into an electron-rich state, which consequently improved its catalytic performance for Hg0 oxidation.