The catalytic activity in the soot combustion is reported for a series of potassium-promoter alumina supported catalysts prepared by the sol-gel method to be used in the catalytic combustion of soot. The studied syste...The catalytic activity in the soot combustion is reported for a series of potassium-promoter alumina supported catalysts prepared by the sol-gel method to be used in the catalytic combustion of soot. The studied systems correspond to CeO2-Al2O3 and La2O3-Al2O3 with charges of 3 and 5 wt% of CeO2 and La2O3. Potassium impregnation is performed to reach 3 atoms of K per nm2 of the mixed oxide. The effect of the potassium incorporation increases its reducibility, decreases the surface area and forms a new type of oxygen that is stronger than the oxygen in mixed oxides with similar chemical nature. The existence of potassium oxides, K2O and oxygen responsible for the vacancies and/or lattice defects (O2−) are related to good catalytic activity. Additionally, the presence of alkali affects the structural and textural characteristics of the catalyst, promoting the catalytic activity in soot combustion.展开更多
文摘The catalytic activity in the soot combustion is reported for a series of potassium-promoter alumina supported catalysts prepared by the sol-gel method to be used in the catalytic combustion of soot. The studied systems correspond to CeO2-Al2O3 and La2O3-Al2O3 with charges of 3 and 5 wt% of CeO2 and La2O3. Potassium impregnation is performed to reach 3 atoms of K per nm2 of the mixed oxide. The effect of the potassium incorporation increases its reducibility, decreases the surface area and forms a new type of oxygen that is stronger than the oxygen in mixed oxides with similar chemical nature. The existence of potassium oxides, K2O and oxygen responsible for the vacancies and/or lattice defects (O2−) are related to good catalytic activity. Additionally, the presence of alkali affects the structural and textural characteristics of the catalyst, promoting the catalytic activity in soot combustion.
