Catalytic removal of NO and dioxins over W-Zr-O x /Ti-Ce-Mn-O x from flue gas: Performance and mechanism study

Co-catalytic removal of multiple pollutants was able to reduce operating costs of enterprises, which was the main development direction for the waste incineration industry. In this work, series W-Zr-O x /Ti-Ce-Mn-O x (WZ/TCM) catalysts were designed to investigate independent NH 3 -SCR, dioxins oxidation and co-catalytic removal of NO and chlorobenzene (CB, the substitute of dioxins). The W-Zr-O x mainly provided solid super acids; CeO 2 and MnO 2 enhanced the redox performance; and TiO 2 provided a large specific surface area. All these factors guaranteed the excellent performance of WZ/TCM catalyst. The NO conversion of WZ/TCM reached 100 %, and the oxidation activity of CB was also higher than 85 % at 350–500 ℃. Meanwhile, the WZ/TCM had high N 2 selectivity and excellent resistances to sulfur and water. In situ infrared diffuse reflectance spectra confirmed that ammonia gas mainly adsorbed on the Lewis acidic sites of the WZ/TCM catalyst and participated in the SCR reaction at low temperature. The ammonia species (NH 4 + ) at the Brønsted sites participated in the reaction at high temperature. Furthermore, the chlorine atom on the chlorobenzene molecule was mainly removed to reduce toxicity when the oxidation of CB was at low temperature, which was deeply oxidized and had a variety of intermediate products at high temperature.