Seminar: Computational Design of Highly Selective Transition Metal Catalysts Encapsulated by Metal-Organic Frameworks for Butane Oxidation to 1-Butanol

Dr. Rachel Getman
Assistant Professor
Clemson University

Catalysts are one of the most important technologies in society today, with catalytic processes accounting for nearly 20% of the US GDP. A key focus of catalysis research is designing catalysts that convert feedstocks into higher value products. One of the greatest challenges is selectivity, i.e., production of a desired product over an undesired one, and this is particularly challenging when the desired product is less thermodynamically stable. For example, the oxidation of butane to 1-butanol is important in the pharmaceuticals and specialty chemicals industries, and selectivity is challenging for two reasons: 1) COand H2O are significantly more stable than butanol, and 2) even 2-butanol is more stable than 1-butanol, since the secondary carbon is more reactive than the primary one. Thus designing a catalyst for production of 1-butanol requires designing precisely tuned catalyst sites that 1) activate the C-H bonds of an alkane without over-dehydrogenating, 2) favor oxidation without overoxidizing, and 3) exclusively target the primary carbon of butane. The aim of this project is to design a metal nanoparticle catalyst encapsulated within a metal-organic framework (MOF) for this purpose. MOFs are porous crystalline solids comprised of metal-based nodes connected by organic “linker” molecules. The appropriate MOF for this system has small pores that force the surface/molecule interaction to occur at the molecule’s terminus. Our results suggest that C-H bond activation proceeds through an “oxygen assisted” mechanism, that a key intermediate in the reaction is the 1-butoxy C4H9O* radical, and that over-dehydrogenation of both the terminal and secondary C is possible. This is true even in MOFs where the pores have diameters that are similar to the kinetic diameter of butane, emphasizing the challenge in designing highly selective catalysts.

Rachel B. Getman is an Assistant Professor in Chemical and Biomolecular Engineering at Clemson University. Her group uses quantum chemical calculations and Monte Carlo and molecular dynamics simulations to investigate molecular-level phenomena at fluid/solid interfaces. She is particularly interested in catalytic processes that occur under aqueous conditions and in catalysis involving metal-organic frameworks (MOFs). Dr. Getman earned her PhD from the University of Notre Dame in 2009, where she worked with Prof. William F. Schneider studying catalytic oxidations under finite pressures of O2. From 2009 – 2011, she was a Postdoctoral Research Fellow with Prof. Randall Q. Snurr, studying gas storage in MOFs. Dr. Getman started her independent career in August 2011, just three months after the birth of her first child, a daughter. She subsequently gave birth to a son, just three days before she was awarded her first grant. Dr. Getman lives with her husband and their two children in Six Mile, SC.

Please view the Dr. Rachel Getman flyer for more information.

This seminar is hosted by the Department of Chemical and Biomolecular Engineering.