Performance of Cu-promoted Pd catalysts prepared by adding Cu using a surface redox method in acetylene hydrogenation

• Published in: Applied catalysis. A, General Vol. 401; no. 1; pp. 12 - 19
• Main Authors: Kim, Seok Ki, Lee, Ji Hoon, Ahn, In Young, Kim, Woo-Jae, Moon, Sang Heup
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.07.2011; Elsevier
• Subjects: ACETYLENE; Acetylene hydrogenation; Catalysis; CATALYSTS; Chemistry; Copper; ETHYLENE; Ethylene selectivity; Exact sciences and technology; General and physical chemistry; HYDROGEN; HYDROGENATION; Palladium; Surface chemistry; Surface redox method; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Acetylene hydrogenation; Cu; Surface redox method; Pd; Ethylene selectivity; Binary compound; Ethylene; Transition metal; Palladium; Selectivity; Conversion; Hydrogenation; Supported catalyst; Acetylene; Promoter; Heterogeneous catalysis; Impregnation; Platinoid; Alumina; Catalyst
• ISSN: 0926-860X; 1873-3875
• DOI: 10.1016/j.apcata.2011.04.048

[Display omitted] ► Cu was selectively deposited onto Pd using a surface redox method. ► Cu was deposited particularly on the low-coordination sites of Pd. ► Added Cu promoted the ethylene selectivity of Pd in acetylene hydrogenation. ► Activity for acetylene hydrogenation was higher for Pd–Cu than for Pd–Ag. Cu-promoted Pd/Al 2O 3 catalysts were prepared by selectively depositing Cu onto the Pd surface using a surface redox (SR) method, and their performance in the selective hydrogenation of acetylene was compared with that of Ag-promoted catalysts prepared by both the SR and the conventional impregnation method. The Cu-promoted catalysts prepared by SR showed higher ethylene selectivity and activity than Ag-promoted catalysts, particularly with small amounts of added promoter. The above results were obtained because Cu added by SR was deposited preferentially onto the low-coordination sites of Pd, which were detrimental to ethylene selectivity but took a small fraction of the Pd surface that was responsible for acetylene conversion, and also because Cu had an intrinsic activity for hydrogenation. The advantages of Cu-promoted catalysts prepared using Cu as a promoter and the SR process as the promoter-addition method were conclusively demonstrated in the present study.