Theodore Walker


Contact: twalker6@wisc.edu

Status: fourth-year Ph.D. student (co-advised with Prof. George Huber)

Undergrad institution: University of Illinois at Chicago (B.S. in Chemical Engineering, cum laude, Honors College)

Research Summary:

A key aspect of a renewable carbon economy is the production and upgrading of biomass-derived chemical intermediates in high yield. My research is focused on the fundamental chemistry underlying acid-catalyzed reactions of these intermediates.

Currently, I am working to understand organic solvent effects in the acid-catalyzed reactions of biomass-derived oxygenates. Mixtures of water with polar aprotic solvents (i.e., mixed solvent environments) can improve reaction performance in biomass valorization processes; a minimum amount of water is often required to facilitate solvation of biomass-derived materials, while the organic co-solvent can enhance the kinetics of biomass conversion reactions, and their selectivities to desired products. However, owing to the lack of broadly-applicable design rules in this context, solvent design in new processes is usually a time-consuming, empirical exercise. My goal is to elucidate the fundamental underlying effects that give rise to changes in chemical reaction kinetics and selectivities as a function of solvent composition. In doing so, I hope to develop a set predictive tools in the form of quantitative structure-reactivity models that will empower the rational design of new liquid phase processes, informed by a first-principles approach.

Bio:

Theodore (Ted) Walker is from Carbondale, Illinois. After five years as an infantryman in the US Army's 75th Ranger Regiment, he used the G.I Bill to obtain a B.S. in chemical engineering from the University of Illinois at Chicago (UIC), where he graduated cum laude from the Honors College. He moved to Madison, WI to join the George Huber and James Dumesic research groups in 2015, where he lives today with his wife Julia, and his sons Alexander and Ira Xavier. His favorite family past times are reading, cooking, and spending any kind of time outdoors. He also volunteers as a 3rd grade science club leader at the Goodman Community Center in Madison.

Publications:

*Co-first authors

    1. T. W. Walker*, A. K. Chew*, B. Demir, Liam Witteman, G. W. Huber, J. A. Dumesic and R. C. Van Lehn, Tuning mixed-solvent environments to direct reaction selectivities in liquid-phase catalytic processes, in prep.  

    2. M. A. Mellmer, C. Sanpitakseree, B. Demir, K. Ma, W. A. Ellitio, P. Bai, R. L. Johnson, T. W. Walker, B. H. Shanks, R. H. Rioux, M. Neurock, J. A Dumesic, Effects of Chloride Ions in Acid-Catalyzed Biomass Dehydration Reactions in Polar Aprotic Solvents, Nature Communications, in press.

    3. T. W. Walker, A. H. Motagamwala, J. A. Dumesic and G. W. Huber, Fundamental Catalytic Challenges to Design Improved Biomass Conversion Processes, Journal of Catalysis, 2019, in press.

    4. M. J. Lindsay, T. W. Walker, S. A. Rankin, J. A. Dumesic and G. W. Huber, Production of monosaccharides and wehy protein from acid whey waste streams in the dairy industry, Green Chem., 2018, 20, 1824-1834

    5. T. W. Walker*, A. K. Chew*, H. Li, B. Demir, Z. C. Zhang, G. W. Huber, R. C. Van Lehn and J. A. Dumesic, Universal kinetic solvent effects in acid-catalyzed reactions of biomass-derived oxygenates, Energy and Environmental Science, 2018, 11, 617-628. **Selected for inclusion in the themed collection: 2018 Energy and Environmental Science HOT Articles**

    6. J. He, M. Liu, K. Huang, T. W. Walker C. T. Maravelias, I., J. A. Dumesic and G. W. Huber, Production of levoglucosenone and 5-hydroxymethylfurfural from cellulose in polar aprotic solvent-water mixtures, Green Chemistry, 2017, 19, 3642-3653.

    7. J. He, K. Huang, K. J. Barnett, S. H. Krishna, D. M. Alonso, Z. J. Brentzel, S. Burt, T. W. Walker, W. F. Bahnholzer, C. T. Maravelias, I. Hermans, J. A. Dumesic and G. W. Huber, New catalytic strategies for alpha-omega diol production from lignocellulosic biomass, Faraday Discussions, 2017, 202, 247-267. 

    8. T. W. Walker*, S. H. Krishna*, J.A. Dumesic and G.W. Huber, Kinetics of levoglucosenone isomerization, ChemSusChem 2017, 10, 129-138.

Honors:

  1. Wisconsin Graduate School Student Research Travel Grant: monetary travel award granted for demonstrated excellence in research – used to present original research at the 2018 Annual Meeting of the American Institute of Chemical Engineers, UW-Madison, Madison, WI, 2018

  2. Wisconsin Distinguished Graduate Fellow (fully funded fellowship awarded for academic achievement), UW-Madison, Madison, WI, 2018

  3. Ronald A. Ragatz Teaching Assistant Award (departmental award for “noteworthy contributions to chemical and biological engineering undergraduate education”), UW-Madison, Madison, WI, 2017.

  4. Assisted in preparation of proposal: Dairy Management Inc. (DMI) grant # 33-AAA7735 A071300 4, “Catalytic Conversion of lactose-rich co-products into value-added components,” UW-Madison, Madison, WI, 2016.

  5. Graduated cum Laude from the UIC Honors College, Chicago, IL, 2015.

  6. Olive C. and Alfred L. Kuehn Scholarship for Engineering, (UIC College of Engineering scholarship for academic achievements), Chicago, IL, 2014.

  7. Illinois Patriot Education Fund Scholarship (veteran’s scholarship for academic excellence), Chicago, IL, 2013.