Influence of ZnO doping and calcination temperature of nanosized CuO/MgO system on the dehydrogenation reactions of methanol

International Journal of Industrial Chemistry

دوره 7، شماره 2، شهریور 2016، صفحه 223-229

نوع مقاله: research article

شناسه دیجیتال (DOI): https://doi.org/10.1007/s40090-016-0076-x

نویسندگان

S. A. El-Molla¹؛ Sh. M. Ibrahim^{* 2، 1}؛ M. M. Ebrahim¹

¹Department of Chemistry, Faculty of Education, Ain Shams University, Roxy, Cairo, 11757, Egypt

²Present address: Department of Chemistry, Faculty of Science, Al-Qassim University, Al-Qassim, Buraidah, 51452, Saudi Arabia

چکیده

Pure and doped catalysts were prepared with ZnO dopant concentration (0.04–0.08 mol) by wet impregnation method followed by calcination at 350–650 °C. The prepared solids were characterized by X-ray diffraction, N₂-adsorption at −196 °C and the methanol conversion as the catalytic probe reaction. The results revealed that the crystallite size and ordering of CuO phase decrease by ZnO-doping for samples calcined at 350–550 °C. Opposite trends were observed by increasing ZnO amount to 0.08 mol (i.e. 9.21 wt%). The specific surface area (S _BET) and the catalytic activity of pure catalyst increase by increasing the calcination temperature to 550 °C and/or increasing the amounts of ZnO up to certain extent reaching to a maximum at 7.07 wt% ZnO; above this concentration catalytic activity of doped samples decreases. But at calcination temperature above 550 °C, the catalytic activity and selectivity decrease. The prepared catalysts are selective towards formaldehyde and methyl formate formation.

کلیدواژه‌ها

ZnO-doping؛ CuO/MgO system؛ Methanol dehydrogenation؛ Conversion؛ Selectivity