Catalytic Oxidation Properties and Characterization of LaSrCo_{0.9}B'_{0.1}O_4 (B'= Mn, Fe, Ni, Cu) Mixed Oxides


Abstract: Using a polyacrylamide gel method, a series of LaSrCo_{0.9}B'_{0.1}O_4 (B'= Mn, Fe, Ni, Cu) mixed oxides were prepared and their catalytic activity was studied with CO and C_3H_8 oxidations as a testing reaction. The results show that the specific effects of B' ions on CO and C_3H_8 oxidations depend on their category. In comparison to LaSrCoO_4 catalyst, the activity of LaSrCo_{0.9}Ni_{0.1}O_4 catalyst for CO and C_3H_8 oxidations is higher, while only lower activity is obtained for Mn, Fe or Cu-doped catalysts. The information derived from TPD, XRD and iodometry experiments shows that the increase in oxidation activity of LaSrCo_{0.9}Ni_{0.1}O_4 catalyst towards CO and C_3H_8 oxidation can be related to the increases in O_2-adsorption quantity, CO_2-desorption quantity, oxygen vacancies and lattice distortion due to the adulteration of nickel. Further investigation shows that the apparent activation energy of LaSrCo_{0.9}Ni_{0.1}O_4 towards CO oxidation is lower than that of LaSrCoO_4.

Keywords: B-site adulteration, catalytic oxidation, Co-based mixed oxides, A_2BO_4

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