Experimental Study on the Deactivating Effect of KNO₃, KCl, and K₂SO₄ on Nanosized Ceria/Titania SCR Catalyst

Table 4

Sum of the property changes after potassium addition.

Sample	Crystal structure of ceria	Microstructure	Chemical state of cerium	Ammonia adsorption	Reducibility of ceria	SCR performance
Ce/TiO2-KNO3-0.25	Amorphous to crystal	Enlarged interstices	Decrease of Ce^3+	Reduced NH3 adsorption	Passivating of ceria	Deactivation
Ce/TiO2-KCl-0.25	Highest crystallinity	Variant particles	Decreased of Ce^3+	Largest decrease of NH3 adsorption	Serious passivating of ceria	Serious deactivation
Ce/TiO2-K2SO4-0.25	High crystallinity	High aggregation	Largest decrease of Ce^3+	Reduced NH3 adsorption	Serious passivating of ceria	Serious deactivation