Catalytic dehydration of ethanol to ethylene over Fe₂O₃/γ-Al₂O₃

A series of Fe₂O₃/γ-Al₂O₃ catalysts with different iron oxide loading were prepared through impregnation method and their catalytic activities for dehydration of ethanol to ethylene were studied. Effects of iron oxide loading, reaction temperature, ethanol concentration and LHSV on the dehydration were investigated. The catalysts were characterized by means of XRD, BET and NH₃-TPD. It was found that through loading of Fe₂O₃, both the pore volume and the pore diameter of the γ-Al₂O₃ could be enlarged, and the surface acid amount, acid density and acid strength distribution of the catalysts were changed obviously. The surface acid amount and the acid density of the Fe₂O₃/γ-Al₂O₃ catalyst with Fe₂O₃ loading 0.5%(mass fraction)were the largest, especially the medium acid amount. And the catalyst showed the best catalytic performance for the dehydration of ethanol to ethylene. Under the optimized reaction conditions; reaction temperature 380°C, ethanol mass fraction 92.4% and LHSV 1.2 h^-1, ethylene yield could reach 98.5% over the Fe₂O₃/γ-Al₂O₃ catalyst with Fe₂O₃ loading 0.5%.