Abstract: Due to growing energy demands as well as environmental concerns, the production of fuels and building block chemicals from renewable sources has become an important area of research. In particular, the use of biomass as feedstock for the production of fuels and building block chemicals holds great promise due to its abundance, accessibility, and worldwide distribution. Owing to the considerable and continuing decrease in the cost of electricity provided by renewable energy sources, electrochemical processes have become viable and appealing routes for reductive and oxidative biomass conversion. The use of electrochemical potential to drive oxidation and reduction reactions has the advantage of performing the reactions at ambient temperature and pressure without requiring the continuous consumption of reductants and oxidants.
Most biomass intermediates contain multiple functional groups. Therefore, achieving reduction and oxidation of only the desired functional groups is critical for efficient and selective upgrading of biomass intermediates. For reductive biomass upgrading, many intermediates containing oxygenated moieties such as carbonyl and alcohol groups must be selectively reduced to form desired fuels and chemicals. Thus, controlling the selectivity between hydrogenation and hydrogenolysis is of great importance for these transformations. For oxidative upgrading, partial oxidation of biomass intermediates to molecules that have greater value than the starting molecules while avoiding their complete oxidation to CO2 is needed. Since most biomass intermediates contain multiple alcohol and aldehyde groups, the ability to selectively dehydrogenate only the desired functional group (alcohol vs aldehyde, primary alcohol vs secondary alcohol) will be vitally important for efficient and selective chemical production via biomass conversion.
In this presentation, we will discuss electrochemical hydrogenation, hydrogenolysis, and dehydrogenation processes and mechanisms that our group has been investigating for the conversion of biomass-derived molecules (e.g., 5-hydroxymethylfurfural, glycerol) to various valuable fuels and chemicals. Through this discussion, we hope to provide new insights to build general mechanistic frameworks for electrochemical hydrogenation, hydrogenolysis, and dehydrogenation reactions based on which more efficient and selective electrocatalysts and optimal reactions conditions to produce desired fuels and chemicals can be identified.
Bio: Kyoung-Shin Choi is a professor of chemistry at University of Wisconsin-Madison. She received her B.S. and M.S. degrees from Seoul National University in South Korea in 1993 and 1995, respectively. She received a Ph.D. degree from Michigan State University in 2000, and then spent two years at the University of California, Santa Barbara as a postdoctoral researcher. She initiated her independent research career as an assistant professor at Purdue University in 2002 and joined the chemistry faculty at University of Wisconsin-Madison as a full professor in 2012. She was a visiting scholar at the National Renewable Energy Laboratory (NREL) in 2008.
Her research combines electrochemistry and materials chemistry to produce and investigate a variety of thin-film type electrodes and catalysts for use in electrochemical and photoelectrochemical applications critical to creating a sustainable future. These applications include sustainable and environmentally benign production of fuels, chemicals, and clean water using renewable energy sources (i.e., solar, biomass). These applications also include resource recovery from waste, where species that contaminate the environment are removed and recovered as useful chemicals, creating a sustainable supply chain for the species.
She was a recipient of a 2006 Alfred P. Sloan Research Fellowship, the 2007 ACS ExxonMobil Faculty Fellowship in Solid-State Chemistry, and the 2010 Iota Sigma Pi Agnes Fay Morgan Research Award. She also received the 2008 Purdue College of Science Outstanding Undergraduate Teaching Award and the 2015 Wisconsin Alumni Research Foundation Innovation Award. In 2023, she was named the 2023 Samsung Ho-Am Prize Laureate in the category of Chemistry and Life Sciences. She has organized numerous symposia for the American Chemical Society (ACS) meetings and Materials Research Society (MRS) meetings as well as for the Gordon Research Conference. She is currently serving as an Associate Editor for Chemistry of Materials and a member of the Board of Directors for Materials Research Society. She also co-founded a startup company, ChloBis Water, Inc.
10:30 – 11: 30 am, Remsen Hall 1, refreshments to follow
The Dr. Paul Emmett and Dr. Richard Kokes Endowed Lecture is the ChemBE lecture intended to be an annual interdisciplinary event with the department of Chemistry at Hopkins. Preference will be given to lecturers who have a focus on research in heterogeneous catalysis, which were Dr. Paul Emmett’s and Richard Kokes’ fields of expertise.
Dr. William Curtis Connor Jr. (U. Mass, Amherst) generously endowed the Emmett-Kokes Lectureship. Dr. Connor received both his BS and PhD degrees in Chemical Engineering from Johns Hopkins. He has a storied career studying catalyst and nanocatalyst morphology and the production of biofuels by heterogeneous catalysts. He has contributed to catalytic kinetic theory and the development of several in situ studies of catalysis.