A novel Cr/WO3-ZrO2 catalyst for the selective catalytic reduction of NOx with NH3

Abstract

A novel Cr/WO3-ZrO2 catalyst prepared by impregnating WO3-ZrO2 (WZr) with Cr has been developed for the selective catalytic reduction of NOx with NH3. The introduction of Cr significantly enhanced the activity of WZr catalyst for the NOx reduction and an optimal loading of Cr is 2 wt%. The redox cycle (Cr3+ + 3W6+ ↔ Cr6+ + 3W5+) and the remarkably enhanced surface acidity can account for the high activity of Cr/WZr catalyst for the reduction of NOx. The present study demonstrated that the combination of Cr with WO3-ZrO2 solid acid catalyst is promising for the control of NOx gas emissions.