The Effect of Alkali Metal Ions (Na, K) on NH3-SCR Response of V/W/TiO2

In this study, we investigated that the effect of alkali metals [Na(Sodium) and K(Potass um)], known as representative deactivating substances among exhaust gases of various industrial processes, on the NH3-SCR (selective catalytic reduction) reaction of V/W/TiO2 catalysts. NO, NH3-TPD (temperature programmed desorption), DRIFT (diffuse reflectance infrared fourier transform spectroscopy analysis), and H-2-TPR analysis were performed to determine the cause of the decrease in activity. As a result, each alkali metal acts as a catalyst poisoning, reducing the amount of NH3 adsorption, and Na and K reduce the SCR reaction by reducing the L and B acid points that contribute to the reaction activity of the catalyst. Through the H-2-TPR analysis, the alkali metal is considered to be the cause of the decrease in activity because the reduction temperature rises to a high temperature by affecting the reduction temperature of V-O-V (bridge oxygen bond) and V=O (terminal bond).