Abstract:
A series of La
1-xRb
xMnO
3 perovskite catalysts (
x=0, 0.1, 0.2, 0.3) were prepared by solvothermal method and characterized by means of XRD, FT-IR, SEM, XPS and H
2-TPR; their catalytic performance in the simultaneous removal of NO and soot was investigated in a fixed-bed micro-reactor. The results show that the La
1-xRb
xMnO
3 catalysts have a single perovskite structure and the Mn species exist in the form of Mn
3+ and Mn
4+. In comparison with LaMnO
3, when La
3+ is partially substituted by Rb
+, more high-valence Mn
4+ and oxygen vacancies are formed in La
1-xRb
xMnO
3, which can improve the redox properties and enhance the catalytic performance of La
1-xRb
xMnO
3. With the increase of Rb
+ content in La
1-xRb
xMnO
3, the conversion of NO increases and the soot combustion temperature decreases. For NO and soot removal over La
0.7Rb
0.3MnO
3,
x=0.3, the peak CO
2 formation temperature (
tmax) is 430 ℃, with a selectivity of 99.0% to CO
2; at 429 ℃, the maximum conversion of NO reaches 59.7%.