Oxidation treatment of diesel soot particulate on CexZr1-xO2.

Catalytic oxidation of diesel soot particulate on Ce(x)Zr(1-x)O(2) catalysts was investigated. Results indicated that Ce/Zr ratios had a significant influence on the catalytic activities. Compared with the ignition temperature (T(i)) of uncatalyzed soot combustion, T(i) of Ce(0.5)Zr(0.5)O(2) with the best catalytic behavior decreased by 80 degrees C. The reactant gas compositions (O(2), H(2)O and NO) affected the catalytic activities too. O(2)-TPD, TG-DTA and XPS characterization results showed that Ce(x)Zr(1-x)O(2) released lattice oxygen continuously to promote the soot combustion even no gas oxygen occurred in the reaction atmosphere. The mechanisms of spill-over and reduction/oxidation functioned synergistically for soot catalytic combustion.