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Al2O3 Effect on the Catalytic Activi

时间:2021-12-11 09:59:42 数理化学论文 我要投稿

Al2O3 Effect on the Catalytic Activity of Cu-ZnO-Al2O3-SiO2 Catalysts for Dimethyl Ether Synthesis from CO2 Hydrogenatio

by a pseudo sol-gel method has been investigated and these catalysts were characterized by XRD,H2-TPR,XPS,NH3-TPD and CO2-TPD techniques. As revealed by XRD and H2-TPR,the added alumina produces high dispersion of CuO and makes the reduction of CuO difficult. XPS analysis detects a remarkably high Al3+ enrichment at the surface of calcined samples,along with a decrease of Eb of Cu 2p3/2,which confirms the Cu-Al interaction.Another important role of Al2O3 would be to incorporate into the SiO2 structure to form the acid-base sites for ether formation. The reaction results shows that the addition of Al2O3 exhibits a promoting effect on the CO2 conversion only when its content is below 1.4%,and an optimal DME selectivity is obtained when 4.0%Al2O3 is added,indicating a better 'synergistic effect' is present between the methanol forming component and the acidic component in bifunctional catalysts. Possible relationship between the catalytic activity and the Cu-Al interaction as well as the surface acidity is discussed.

作 者: Jiyuan Wang Chongyu Zeng   作者单位: College of Chemistry and Chemical Engineering,Nanjing University of Technology,Nanjing 210009,China  刊 名: 天然气化学(英文版)  ISTIC SCI 英文刊名: JOURNAL OF NATURAL GAS CHEMISTRY  年,卷(期): 2005 14(3)  分类号: O6  关键词: carbon dioxide   hydrogenation   dimethyl ether   copper   zinc oxide   alumina   silicon dioxide   synthesis