EFFECT OF CARRIER GAS ON n-BUTANE ISOMERIZATION OVER SO42-/ZRO2-AL2O3

Abstract

Abstract: The alumina-promoted sulfated zirconia catalysts were prepared by precipitation-impregnation method. The effect of carrier gas on n-butane isomerization over SO42-/ZrO2-Al2O3 was investigated in a continuous flow fixed-bed micro-reactor at atmospheric pressure and 200 ℃ using hydrogen, nitrogen, and mixture of hydrogen and nitrogen as carrier gas. The results showed that the inert nitrogen only plays the role of diluent gas, which decreases the concentration of n-butane and intermediate species. However, the hydrogen adsorbed on the catalyst surface is active in reaction. In addition to dilution, the hydrogen accelerates the desorption of intermediate species and product molecules from the catalyst surface through competitive adsorption with n-butane and improves the stability of catalyst significantly due to interaction between H2 and catalyst active size, which is the determining factor for this improvement.

Key words: carrier gas, SO42-/ZrO2-Al2O3, n-butane isomerization, deactivation

CLC Number:

References

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