Premium
Temperature‐programmed surface reaction study on C 2 ‐oxygenate synthesis over SiO 2 and nanoporous zeolitic material supported Rh–Mn catalysts
Author(s) -
Ma Hongtao,
Yuan Zhongyong,
Wang Yi,
Bao Xinhe
Publication year - 2001
Publication title -
surface and interface analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 90
eISSN - 1096-9918
pISSN - 0142-2421
DOI - 10.1002/sia.1042
Subject(s) - catalysis , chemistry , acetaldehyde , thermal desorption spectroscopy , oxygenate , inorganic chemistry , desorption , adsorption , amorphous solid , syngas , mesoporous material , ethanol , organic chemistry
Temperature‐programmed surface reaction (TPSR), temperature‐programmed reaction (TPR) and temperature‐programmed desorption (TPD) were used to study the synthesis of C 2 ‐oxygenates from syngas over Rh–Mn‐based catalysts supported on amorphous silica and mesoporous MCM‐41 supports. Both TPD and TPSR reveal the existence of several different kinds of CO species on the catalyst surface in the course of the catalytic reaction (linear, geminal, bridged and tilt‐adsorbed CO species) but only the bridged form and tilt‐adsorbed CO species are the precursors for CO dissociation and the formation of C 2 ‐oxygenates. The formation temperature of acetaldehyde is higher than that of ethanol, which suggests that they may be formed via different mechanisms. The ethanol formation activity over the Rh–Mn/MCM‐41 catalyst is lower than that over the Rh–Mn/SiO 2 , which suggests that the number of active sites for ethanol formation are fewer on the surface of Rh–Mn/MCM‐41. However, the acetaldehyde formation activities are almost identical for the Rh–Mn catalysts supported on amorphous SiO 2 and MCM‐41, meaning that acetaldehyde and ethanol might be formed on different active sites. Copyright © 2001 John Wiley & Sons, Ltd.