Selective Hydrodeoxygenation of m-Cresol over Bifunctional Metal-Acid Catalysts

2012 Spring Symposium

Andrew Foster, Phuong Do, Jingguang Chen and Raul F. Lobo
Department of Chemical and Biomolecular Engineering
University of Delaware

Abstract – Upgrading of biomass derived pyrolysis oil is necessary to produce liquid fuels that can seamlessly be integrated with the current transportation fuel infrastructure and hydrodeoxygenation (HDO) is one of the most effective methods to accomplish this task. In this talk we will describe the HDO of m-cresol (3-methylphenol) investigate as a model reaction for the HDO of the phenolic fraction of pyrolysis oil of lignocellulosic biomass. To facilitate selective removal of oxygen without further hydrogenation of unsaturated C-C bonds, experiments were conducted at low hydrogen pressures. Kinetic studies in a plug-flow reactor show that toluene can be selectively produced from m-cresol over a Pt/γ-Al2O3 catalyst at pressures as low as 0.5 atm H2 and 533 K. A reaction network has been developed based on investigation of the reactions of m-cresol, and the observed reaction products and intermediates over Pt/γ-Al2O3 and other supports. m-Cresol HDO proceeds by a bifunctional mechanism, requiring metal-catalyzed hydrogenation of the aromatic ring followed by acid-catalyzed dehydration. The degree of hydrogenation of the pool of intermediates prior to dehydration largely determines the resultant product distribution. The effect of the addition of a second metal (Ni and Co) on catalysts activity is also investigated. It is shown that selective production of toluene requires the dehydration to occur before saturation of the aromatic ring.

Speaker Biography – Raul F. Lobo is professor of Chemical Engineering at the University of Delaware and Director of the Center for Catalytic Science and Technology. His research interests span the development of novel porous materials for catalysis and separations, the chemistry of zeolites at high temperatures, the development of novel photocatalysts and the scientific aspects of catalyst synthesis. He has published over one hundred refereed reports and he is co-inventor in three US patents. He obtained his undergraduate degree in Chemical Engineering at the University of Costa Rica and later moved to California to pursue graduate studies in Chemical Engineering at Caltech. He worked for one year at Los Alamos National Laboratory, New Mexico as a postdoctoral fellow and started his academic career at the Center for Catalytic Science and Technology, Department of Chemical Engineering, University of Delaware in 1995.