PREPARATION OF ZIRCONIUM-DOPED ALUMINA AND ITS CATALYTIC REFORMING PERFORMANCE

Abstract

Abstract: High-purity alumina doped with zirconium was prepared by the hydrolysis method of aluminum alkoxide, and the effects of zirconium doping amount on its physical and chemical properties, such as specific surface area and pore structure, were investigated. Using the zirconium-doped alumina as raw material, a zirconium-doped alumina carrier was prepared by extrusion, further loaded with Pt to prepare reforming catalyst. Naphtha was used as raw material, the effects of zirconium content variation on the catalyst’s reactivity were investigated, and the influencing mechanism was also discussed. The results showed that the introduction of Zr could change the L acid strength of the γ-Al₂O₃ carrier, thus changing the ratio of the metal center to acid center on the catalyst. When the mass fraction of Zr was 0.20%-0.33%, the acid center and metal center of the catalyst exhibited good synergy, displaying higher catalytic activity and aromatic selectivity for naphtha reforming.

Key words: zirconium-doped, alumina, naphtha, catalytic reforming

References

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