Title "Catalytic Reactions of Hydrocarbons by Heterogenous, Lewis Acid Catalysts"

Dr. Jeffrey T. Miller, Professor of Chemical Engineering

Davidson School of Chemical Engineering, Purdue University

Hosted By: Dr. Wenyu Huang

Abstract

Lewis acid catalysts, where electron lone pairs from heteroatoms (e.g., N, O, Cl) interact with ionic metal centers to form coordinate covalent bonds, are widely known in homogeneous catalysis and biochemistry. At low reaction temperatures, Lewis acids do not typically react with olefins or alkanes. Furthermore, Lewis acids are not known to catalyze hydrogenation reactions, which requires activation of the σ bonds in H2 or alkanes. However, at higher temperatures applicable to heterogeneous catalysts, hydrocarbon reactions involving Lewis acid site can occur.

Highly loaded Ga3+ Lewis acid sites on SiO2 and Al2O3 supports were synthesized to explore the structure and role of the support type on catalytic reactions of alkanes and olefins. The structures and types of acid sites were characterized using X-ray absorption spectroscopy and pyridine infrared spectroscopy, respectively. Additionally, their catalytic activity, including reaction rates and product selectivity, was evaluated for propane dehydrogenation and olefin oligomerization reactions. For the latter reaction, hydrogen transfer, double-bond isomerization, and the formation of non-oligomers products were also observed. These reactions have also been observed for other heterogenous, non-Ga Lewis acid catalysts.

Bio

Jeff Miller joined the Purdue faculty in Davidson School of Chemical Engineering in 2015.  His research interests include development of new catalysts for conversion of abundant shale gas hydrocarbons to fuels and chemicals.  His research group is also interested in synchrotron characterizations of these catalysts under reaction conditions.  Prior to joining Purdue, he was the Heterogeneous Catalysis Group Leader at Argonne National Laboratory’s Chemical Sciences and Engineering Division. His group developed new catalytic materials and fundamental understandings for energy production. Prior to joining Argonne, Jeff worked for the Amoco Oil Company (now BP) for more than 27 years.