Effect of assembly method on the performance of Ce-Mn-Ti system in NH3-SCR

Abstract

The components of the composite catalyst show different properties when they appear in different positions. The research on the assembly method of the composite catalyst is beneficial for exploring the potential of the catalyst. In this work, the Ce-Mn-Ti catalyst is prepared by different assembly methods. The results show that the catalyst with Ce-Mn co-doping has the best structure assembly mode, which is suitable for the denitration reaction of NH3-SCR. As a protective agent, Ce is doped into TiO2 to make the intermetallic interaction become more intense. Since doping Ce would cause lattice distortion and form short-range ordered bonds of Ce-O-Ti, thus reducing the pore size of catalyst and increasing the specific surface area of catalyst. At the same time, Ce also has excellent oxygen storage and oxygen release capacity, which can produce more oxygen vacancies. Mn is the active center, and doping into TiO2 can produce more Brønsted acid sites. Meanwhile Mn doping is beneficial to charge dispersion bond energy and optimize electron transport path. Ce-Mn co-doping can also enhance the interaction between metals. In this work three catalysts – CeMnTiO2, Ce/MnTiO2 and Mn/CeTiO2 were prepared, and the effects of doping and load modification methods on the active components were investigated.

Keywords

• NH3-SCR
• Co-doped
• Electronic transfer
• Surface acidity
• In-situ DRIFTS