Abstract: Series of Ba1－xLaxFeAl11O19－δ hexaaluminate catalysts were prepared by (NH4)2CO3 co-precipitation method and their performance for methane catalytic combustion was studied. The obtained materials were characterized by XRD, Diffuse UV-Vis, FT-IR, TPR, and N2 BET techniques. The results showed that partial substitution of Ba with La in Fe-hexaaluminates could enhance catalytic activity for methane combustion, and the optimal catalyst was Ba0.2La0.8FeAl11O19－δ hexaaluminate, whose light-off temperature was as low as 495 ℃ denoted by 10％ conversion of methane (VCH4/VO2/VN2=1/4/95). XRD and SEM characterization indicated that the samples formed well-defined hexaaluminate phase after calcination at 1 200 ℃ for 5 h, and the dopant of La could promote the formation of hexaaluminate phases. UV-Vis-DR characterization revealed that the oxide state of Fe is ＋3 in Ba1－xLaxFeAl11O19－δcatalysts. The synergism between Ba, La and Fe was observed based on the results of UV-VisDR, FT-IR and TPR.

Key words: La-doped, Fe-substituted Ba (La) hexaaluminate, Catalytic combustion of methane, Synergism