Honeycomb CuO/Al2O3/Cordierite Catalyst for Selective Catalytic Reduction of NO by NH3—Effect of Al2O3 Coating

Al 2 O 3 -coated cordierite has been widely used as a catalyst’s support. In this work, three Al 2 O 3 precursors or alumina sols are studied to understand the effect of type, viscosity, and grain size of the sols and Cl − on properties and SCR activities of honeycomb CuO/Al 2 O 3 /cordierite catalysts. X-ray diffraction (XRD), N 2 adsorption, scanning electron microscopy and energy dispersive X-ray (SEM-EDX) techniques are used for analyses. Results show that the viscosity and average grain size of the sol have significant influences on the amount and stability of the Al 2 O 3 coating. The sol synthesized from AlCl 3 and aluminum is the best among the three sols in terms of less coating cycle, stability of the coating, and selective catalytic reduction (SCR) activity. Cl 1− introduced in preparation must be washed out because it deactivates the SCR activity.