2013 Spring Symposium
Charles H.F. Peden1, Charles A. Mims2, Yong Yang1,3, Donghai Mei1, Charles T. Campbell3
1 Institute for Integrated Catalysis, Pacific Northwest National Laboratory,
P.O. Box 999, Richland, WA 99354 USA
2 Department of Chemical Engineering and Applied Chemistry
University of Toronto, Toronto ON M5S3E5 Canada
3 Department of Chemistry University of Washington, Seattle WA 98195 USA
Abstract — The mechanism of methanol synthesis on copper-based catalysts has been extensively studied and remains a target of research because of the significance of this reaction in the chemical industry and methanol’s potential as a liquid energy/hydrogen carrier. A recent DFT and microkinetic modeling study by Grabow and Mavrikakis [1] contains a thorough review of the current state of our understanding of this reaction. These recent models allow for conversion of both CO (by direct hydrogenation) and CO2 (via formate intermediates) to methanol. Although tracer experiments have shown that CO2 is the preferred reactant over CO in H2:CO:CO2 mixtures under commercial conditions, the relative importance of these channels under various conditions is still uncertain [1]. Furthermore, the role of water in the reaction mechanism has received little attention, despite long established effects of water and CO2 in the conversions of syngas [2]. Our recent DFT study has pointed out that water can have significant effects in methanol synthesis and that a separate methanol formation mechanism via a carboxyl intermediate is energetically possible [3]. In this presentation, we describe particularly strong effects of water on the conversion of both CO and CO2 at temperatures below those of commercial practice, and support for an intermediate common to both CO and CO2 [4].
References
1. Grabow, LC; Mavrikakis, M ACS Catal. 1 (2011) 365.
2. Parameswaran, VR; Lee, S; Wender; I Fuel Science Techn. Intl. 7 (1989) 899.
3. Zhao, Y-F; Yang, Y; Mims, CA.; Peden, CHF; Li, J; Mei, D J. Catal. 281 (2011) 199.
4. Yang, Y; Mims, CA.; Mei, DH; Peden, CHF; Campbell, CT J. Catal. 298 (2012) 10
Charles H.F. Peden
Biography — Chuck Peden is Associate Director of the Institute for Integrated Catalysis at Pacific Northwest National Laboratory (PNNL). He is also a Laboratory Fellow, and manages and participates in multiple technical projects within the Physical Sciences Division at PNNL. He joined PNNL in 1992 following a nine-year tenure at Sandia National Laboratories in Albuquerque, New Mexico, as a Senior Member of the technical Staff in the Inorganic Materials Chemistry Department. Peden’s main research interests are in the surface and interfacial chemistry of inorganic solids; in particular, the heterogeneous catalytic chemistry of metals and oxides with an emphasis on reaction mechanisms and materials structure/function relationships. He is best known as a leader in the development of the mechanisms of automobile exhaust catalytic reactions. After graduating with distinction from California State University, Chico with a B.S. in chemistry, Peden completed his Ph.D. in physical chemistry at the University of California, Santa Barbara under the direction of Ralph G. Pearson. He then spent two years as a postdoctoral associate with D. Wayne Goodman at Sandia National Laboratories in Albuquerque, New Mexico before joining the scientific staff there. Peden has written or contributed to more than 235 peer-reviewed publications (H-factor > 40) and 3 issued U.S. patents on topics such as automobile exhaust catalysis, hydrocarbon reforming on bimetallic catalysts, the structure of hydroprocessing catalysts, the synthesis and characterization of novel supported solid acid catalysts, and the structure and chemistry of oxide surfaces. He is a member of the American Chemical Society, the American Institute of Chemical Engineers, the Society of Automotive Engineers, and the North American Catalysis Society. Peden was elected a Fellow of the American Vacuum Society in 2000, and the American Association for the Advancement of Science in 2009 and the American Chemical Society in 2012. He currently serves as Past-Chair of the ACS Catalysis Science and Technology (CATL) Division.