The Effect of H2 O on the Use of Ethanol as Reductant in the SCR System

Abstract

In this experimental study, effects of H2O on the use of ethanol as reducing agents were investigated on the AgPt-W-Ti/Cordierite catalyst. Ag-Pt-W-Ti/Cordierite catalyst was synthesized using the impregnation methodfor selective catalytic reduction (SCR) of NOx. To investigate the effects of H2O addition on the NOx conversionratios, tests were carried out at 200-270 ° C under 30000 h-1 GHSV using three different reductants (ethanol,5% H2O - 95% ethanol, 10% H2O - 90% ethanol). The catalytic activity of the catalyst increased with increase inexhaust gas temperature. The highest NOx conversion ratio was 89.9% at 270 oC with ethanol. The tests showedthat when the H2O content of the reductant increased from 5% to 10%, the NOx conversion ratios significantlydecreased at temperatures below 240 oC. NOx conversion ratios enhanced as engine load increased.