Influence of Ca doping on MnOx/TiO2 catalysts for low-temperature selective catalytic reduction of NOx by NH3

A series of Ca doped MnOx/TiO2 catalysts was synthesized in this paper by using wet-impregnation method. Thereafter, the influence of Ca on the performance of the MnOx/TiO2 catalysts for low-temperature selective catalytic reduction of NOx by NH3 was investigated. Experimental results showed that Ca doping could have negative effect on the activities of the MnOx/TiO2 catalysts. This could be due to the resultant less acid sites and lower NO oxidation ability. However, at a high Ca doping, this effect would become dilute, presumably due to the formation of CaTiO3 that weakened the deactivation.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The effect of Ca on MnOx/TiO2 for low-temperature SCR reaction was firstly studied. ► Low Ca doping would suppress the catalytic activity. ► When the Ca content was shifted to 10 wt.%, the activity would be somewhat recovered. ► The formation of CaTiO3 could weaken the deactivation of Ca doping.