In terms of the reaction of COreduction to CO with hydrogen, COconversion is very low at low temperature due to the limitation of thermodynamic equilibrium(TE). To overcome this limitation, plasma catalytic reductio...In terms of the reaction of COreduction to CO with hydrogen, COconversion is very low at low temperature due to the limitation of thermodynamic equilibrium(TE). To overcome this limitation, plasma catalytic reduction of COto CO in a catalyst-filled dielectric barrier discharge(DBD) reactor is studied. An enhanced effect of plasma on the reaction over Au/CeOcatalysts is observed. For both the conventionally catalytic(CC) and plasma catalytic(PC, Pin= 15 W) reactions under conditions of 400 °C, H/CO= 1,200 SCCM, GHSV = 12,000 mL·gcat·h, COconversions over Au/CeOreach 15.4% and 25.5% due to the presence of Au, respectively, however, those over CeOare extremely low and negligible. Moreover,COconversion over Au/CeOin the PC reaction exceeds 22.4% of the TE conversion. Surface intermediate species formed on the catalyst samples during the reactions are determined by in-situ temperatureprogrammed decomposition(TPD) technique. Interestingly, it disclosed that in the PC reaction, the formation of formate intermediate is enhanced by plasma, and the acceleration by plasma in the decomposition of formate species is much greater than that in the formation of formate species on Au/CeO. Enhancement factor is introduced to quantify the enhanced effect of plasma. Lower reactor temperature, higher gas hourly space velocity(GHSV), and lower molar ratio of H/COwould be associated with larger enhancement factor.展开更多
基金supported by the National Natural Science Foundation of China(21673030)the Fundamental Research Funds for the Central Universities(DUT16QY49)
文摘In terms of the reaction of COreduction to CO with hydrogen, COconversion is very low at low temperature due to the limitation of thermodynamic equilibrium(TE). To overcome this limitation, plasma catalytic reduction of COto CO in a catalyst-filled dielectric barrier discharge(DBD) reactor is studied. An enhanced effect of plasma on the reaction over Au/CeOcatalysts is observed. For both the conventionally catalytic(CC) and plasma catalytic(PC, Pin= 15 W) reactions under conditions of 400 °C, H/CO= 1,200 SCCM, GHSV = 12,000 mL·gcat·h, COconversions over Au/CeOreach 15.4% and 25.5% due to the presence of Au, respectively, however, those over CeOare extremely low and negligible. Moreover,COconversion over Au/CeOin the PC reaction exceeds 22.4% of the TE conversion. Surface intermediate species formed on the catalyst samples during the reactions are determined by in-situ temperatureprogrammed decomposition(TPD) technique. Interestingly, it disclosed that in the PC reaction, the formation of formate intermediate is enhanced by plasma, and the acceleration by plasma in the decomposition of formate species is much greater than that in the formation of formate species on Au/CeO. Enhancement factor is introduced to quantify the enhanced effect of plasma. Lower reactor temperature, higher gas hourly space velocity(GHSV), and lower molar ratio of H/COwould be associated with larger enhancement factor.