Bimetallic Pd-Ce/γ-Al2O3 series catalysts were prepared by impregnation method in our experiment.Effects of the catalysts performance on the low concentration methane catalytic combustion were investigated.Structures and chemical properties of the catalysts were characterized and analyzed by scanning electron microscopy (SEM),N2 adsorption/desorption isotherms and H2-temperature programmed reduction (H2-TPR).Effects of different calcination temperature and additive dosage on catalytic activities were studied;the catalytic activity of the recycling catalysts was investigated at the same time.The results showed that the optimal calcination temperature was 550℃,the highest efficiency difference of about 40% at the same catalytic temperature.Compared with the single metal catalyst,bimetallic catalyst was benefit to improve the catalytic activity,but the catalytic effect was not obvious.However,the catalytic activity could be improved significantly when being used for many times,compared with the first experiment,the catalytic efficiency of the highest difference of about 50%.The probably reason were that the synergistic effects between PdO and CeO2 could be strengthen,the dispersion of the PdO could be improved,and the desorption energy of the adsorption oxygen could be reduced,all of which enhanced the catalyst activity.
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