The effect of H2O 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 Ag-Pt-W-Ti/Cordierite catalyst. Ag-Pt-W-Ti/Cordierite catalyst was synthesized using the impregnation method for selective catalytic reduction (SCR) of NOx. To investigate the effects of H2O addition on the NOx conversion ratios, 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 in exhaust gas temperature. The highest NOx conversion ratio was 89.9 % at 270 oC with ethanol. The tests showed that when the H2O content of the reductant increased from 5 % to 10 %, the NOx conversion ratios significantly decreased at temperatures below 240 oC. NOx conversion ratios enhanced as engine load increased.

Keywords

• Catalyst
• SCR
• NOx
• Diesel engine
• Reductant

References

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