Catalytic oxidation of carbon monoxide over perovskite-type catalysts La(1+x)/2Sr(1-x)/2Co1-xCuxO3-λ

Catalytic oxidation of carbon monoxide over the perovskite type mixed catalysts La(1+x/2)Sr(1-x/2)Co1-xCuxO3-lambda (0 1 less than or equal to x less than or equal to 0.9) has been investigated. Activity testing results show that the catalysts in the range x = 0.1-0.4 are of high activity for CO oxidation, especially, the catalyst of x = 0.4 can make CO to oxidize completely below 170 degrees and is regarded as the optimum catalyst for CO oxidation. Studies also suggest that oxidizing atmosphere favors CO oxidation over perovskite catalyst, the catalyst of x = 0.4 has higher resistance to sulfur dioxide poisoning at higher temperature. Studies on the active oxygen species by thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and desorption of oxygen suggest that the important active oxygen species for CO oxidation is the surface-absorbed oxygen.