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Effect of Promoters on Performance of CuOZnOZrO2 Catalyst Prepared for CO2 Hydrogenation to Methanol
Li Peipei, Qin Yucai, Li Qiang, Mo Zhousheng, Zhang Yuanyuan, Song Lijuan
CuOZnOZrO2 catalyst was modified by combustion method, using Al2O3, CeO2, NiO metal oxides as promoters. The effects of Al2O3, CeO2, NiO on phase composition and catalyst structure were illuminated by using Xraydiffraction (XRD), temperatureprogrammed reduction ofhydrogen(H2TPR), temperatureprogrammed desorption of hydrogen (H2TPD) and carbon dioxide (CO2TPD) techniques. And the effects of the three chosen promoters on catalytic performance for CO2 hydrogenation to methanol were studied in a fixedbed plug flow reactor. The results indicated that the three promotes of Al2O3, CeO2, NiO all contributed to improving theactivity of catalysts and CeO2modified catalyst had best catalytic performance. Moreover, the three promotes all could inhibit CuO crystal grain growth and improve the dispersion of CuO, which could benefit the reduction of catalysts and H2 adsorptiondissociation. Besides that, the three metal oxides could modulate the intensity amount of basic sites on the catalyst surface in different degrees. Comparing with NiOmodified catalyst, CeO2modified catalyst and Al2O3 modified catalyst both possessed higher basic intensity and more basia sites, which led to CO2 adsorptionactivation easily.
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