TY - JOUR
T1 - Oxidative dehydrogenation of ethane over alumina-supported Pd catalysts. Effect of alumina overlayer
AU - Fu, Baosong
AU - Lu, Junling
AU - Stair, Peter C.
AU - Xiao, Guomin
AU - Kung, Mayfair C.
AU - Kung, Harold H.
N1 - Funding Information:
This work was supported by The Dow Chemical Company via the Methane Challenge program and the US Department of Energy, Grant DE-FG02-01ER15184. Baosong Fu was supported in part by the China Scholarship Council. We thank Dr. Federico A. Rabuffetti for the TGA measurements.
PY - 2013/1
Y1 - 2013/1
N2 - The effect a 45 atom-thick overlayer of aluminum oxide, deposited by atomic layer deposition, was investigated on a 2.5 wt.% Pd/Al2O3 catalyst in which the Pd nanoparticles were encapsulated by the support consequent to the preparation method. The overlayer suppressed the activity for oxidative dehydrogenation of ethane, but it also effectively prevented metal sintering and suppressed coking for reactions at high temperatures. On the catalyst with the alumina overlayer, a steady activity was observed even at 600 °C and above when the gaseous oxygen was completely consumed, while attaining 70% selectivity for ethene at 38% conversion, versus 10% selectivity at comparable conversions without the overlayer. The overlayer preferentially deposited on edge Pd atoms, as indicated by preferentially suppression of the CO chemisorption peak at 2056 cm-1, which are responsible for coking. The high ethene selectivity at 675 °C could be due to coupled homogeneous and heterogeneous reactions at the high temperature, together with phase change of PdO to Pd.
AB - The effect a 45 atom-thick overlayer of aluminum oxide, deposited by atomic layer deposition, was investigated on a 2.5 wt.% Pd/Al2O3 catalyst in which the Pd nanoparticles were encapsulated by the support consequent to the preparation method. The overlayer suppressed the activity for oxidative dehydrogenation of ethane, but it also effectively prevented metal sintering and suppressed coking for reactions at high temperatures. On the catalyst with the alumina overlayer, a steady activity was observed even at 600 °C and above when the gaseous oxygen was completely consumed, while attaining 70% selectivity for ethene at 38% conversion, versus 10% selectivity at comparable conversions without the overlayer. The overlayer preferentially deposited on edge Pd atoms, as indicated by preferentially suppression of the CO chemisorption peak at 2056 cm-1, which are responsible for coking. The high ethene selectivity at 675 °C could be due to coupled homogeneous and heterogeneous reactions at the high temperature, together with phase change of PdO to Pd.
KW - Alumina overlayer
KW - Ethane
KW - Oxidative dehydrogenation
KW - Pd catalyst
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U2 - 10.1016/j.jcat.2012.10.023
DO - 10.1016/j.jcat.2012.10.023
M3 - Article
AN - SCOPUS:84870875797
VL - 297
SP - 289
EP - 295
JO - Journal of Catalysis
JF - Journal of Catalysis
SN - 0021-9517
ER -