| Summary: | Zeolite catalysts that could allow the efficient synthesis of <i>n</i>-butene, such as 1-butene, <i>trans</i>-2-butene, and <i>cis</i>-2-butene, in the dimethyl ether (DME)-to-olefin (DTO) reaction were investigated using a fixed-bed flow reactor. The zeolites were characterized by N<sub>2</sub> adsorption and desorption, X-ray diffraction (XRD), thermogravimetry (TG), and NH<sub>3</sub> temperature-programmed desorption (NH<sub>3</sub>-TPD). A screening of ten available zeolites indicated that the ferrierite zeolite with NH<sub>4</sub><sup>+</sup> as the cation showed the highest <i>n</i>-butene yield. The effect of the temperature of calcination as a pretreatment method on the catalytic performance was studied using three zeolites with suitable topologies. The calcination temperature significantly affected DME conversion and <i>n</i>-butene yield. The ferrierite zeolite showed the highest <i>n</i>-butene yield at a calcination temperature of 773 K. Multiple regression analysis was performed to determine the correlation between the six values obtained using N<sub>2</sub> adsorption/desorption and NH<sub>3</sub>-TPD analyses, and the <i>n</i>-butene yield. The contribution rate of the strong acid site alone as an explanatory variable was 69.9%; however, the addition of micropore volume was statistically appropriate, leading to an increase in the contribution rate to 76.1%. Insights into the mechanism of <i>n</i>-butene synthesis in the DTO reaction were obtained using these parameters.
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