SO₂ Tolerance of Rice Hull Ash Based Fe-Cu Catalysts for Low-Temperature CO-SCR of NO

Abstract

Rice husk ash (RHA) has potential as a supporter of catalysts. In this research, we studied the activity and SO2 tolerance of RHA-based Fe-Cu oxide in the reduction of NO by CO. Characterization methods were employed to study the properties of the catalysts and their SO2 tolerance. Activity and SO2 resistance were also tested at different temperatures. We recommend two catalysts with SO2 resistance ability: Fe0.67Cu0.33/RHA (the highest catalytic activity) and Fe0.8Cu0.2/RHA. The NO removal rate hardly changed with the addition of SO2 and was kept at about 100%. However, the CO conversion rate decreased with increasing SO2 at the lower reaction temperatures, which may be due to the formation of sulfites. Fortunately, the deactivation was reversible and can be reduced with an increase in the reaction temperature. The results of our research may help promote the application of CO-SCR.

Keywords

• rice husk ash
• Fe-Cu catalysts
• NO reduction
• SO₂ resistance
• CO-SCR