(4do) A Theory of Catalysis: Enabling Design and Interpretation of Experiments on Catalysts with Multiple Functionalities and Real Distributions of Active Sites

A Theory of Catalysis: Enabling Design and Interpretation of Experiments on Catalysts with Multiple Functionalities and Real Distributions of Active Sites

Greg Collinge, Ph.D. Chemical Engineering

2014-2019: Ph.D, Washington State University (Advisor: Jean-Sabin McEwen)

2019-present: Postdoc, Pacific Northwest National Laboratory (Advisor: Roger Rousseau)

Relevant Metrics:

19 publications. 8 first author (published), 7 first author (in preparation), 100 total citations, h-index of 7 (Google Scholar). 12 presentations (2 invited). 8 funded proposals. 4 Ph.D. fellowships. 4 scholarly awards. 10 outreach and volunteer events.

Research Interests in Brief:

• Advanced molecular and kinetic modeling—leveraging supercomputing, quantum chemistry, statistical mechanics, and interpretable/physics-informed data science/machine learning techniques—used to identify mechanisms, develop/discover new catalysts, and extract thermodynamic and kinetic information needed to develop a holistic theory of catalysis.
• Multi-functional catalyst development for upgrading and conversion of distributed biomass feedstocks (i.e., distributed manufacturing).
• Green H₂ production for sustainable NH₃ synthesis, bio-oil upgrading, and CO₂
• Process intensification for rapid improvement and development of transitional and future carbon-responsible technologies.
• Mitigation of point-source greenhouse gas emissions in translational technologies.
• Carbon-neutral/negative CO₂ capture and conversion or recycle for future technologies.
• Defining and determining both local and global entropy in chemical systems: ab initio molecular dynamics, cluster expansions, and associated multiscale kinetic modeling.
• Development of a theory of (heterogenous) catalysis as a means of:
  • Facilitating invention of new catalytic technologies exploiting chemical processes important to the interconversion of electrical and chemical energy (in the context of both traditional and intermittent energy sources).
  • Elucidating site distributions on real catalysts where site-cooperativity amongst multiple intersecting reactions influence dynamics of catalyst/electronic structures.
  • Inducing changes in catalytic cycles and deactivation pathways in catalyst design.
  • Maximizing the technological impact of nano- and single atom stabilized structures via determination and control of non-local effects, electron transport, and reactivity.
  • Taking advantage of redox conversions and confinement effects enabled by traditional and novel support materials, with careful attention to practical impact at reactor scales.

Teaching Interests in Brief:

• Undergraduate level: strong desire to teach fundamentals of chemical engineering—such as materials and energy balances, thermodynamics, kinetics, and transport phenomena. My groups’ research will provide specific examples illustrating fundamental concepts.
• Semi-flipped classroom with audience response systems incorporated for instant self-assessment and feedback. I will record 5–10-minute lecture videos going over key concepts paired with guided inquiry worksheets. Group projects, introducing the idea of working in an engineering “firm”, will be assigned as part of any course taught.
• Graduate level: chemical engineering kinetics (nonideal reactors), and a strong desire to design an “advanced microkinetic modeling of catalysis” course based on my research.
• Mentorship of graduate students through a collaborative lens, enhancing their academic and outreach portfolios to ensure success both during and after graduate school. I believe in life-long mentorship.

Overview:

President Biden has set a national objective to reduce the United States’ greenhouse gas emissions by at least half by 2030—with an overarching goal of achieving a net-zero economy by 2050.[1] With the existential threat of climate change ever looming, meeting these or similar goals will remain critical challenges regardless of future administration priorities. The vast majority of current emissions come primarily from three sectors: transportation, industry, and electricity.[2] The utilization of renewable energy sources (wind, solar, etc.) promises to combat emissions in those sectors or subsectors that can be electrified (light-duty vehicles, power generation, etc.), but industrial chemical processes and heavy-duty vehicle fleets (shipping, aviation, etc.) will require considerable innovation to sustainably transition to a carbon-neutral future. In the meantime, we will need to develop new, economically pragmatic ways of using (or reusing) carbon sources responsibly and sustainably across all carbon utilizing sectors. Therefore, meeting the 2030 and 2050 goals will require, respectively, the process intensification of carbon-responsible transitional technologies alongside the development of the carbon-neutral/carbon-negative ones of the future.

Few industrially relevant chemical reactions occur without a catalyst, as evidenced by their over 33 billion USD per year market share in 2019 and expected annual growth rate of 4.4% into this decade.[3] Heterogenous catalysts make up the majority of the catalyst market.[3] This is because heterogeneously catalyzed reactions are critical to the aforementioned sectors, encompassing (amongst many others) petroleum refining, biomass upgrading, carbon capture and recycling, vehicle emissions control, and the synthesis of polymers, petrochemicals, and myriad so-called “fine” chemicals (biocides, active pharmaceutical ingredients, and other specialty chemicals). In short, if we are to innovate and develop novel technologies capable of meeting the threat of climate change while maintaining social and economic demands, we must target these catalyzed processes and swiftly optimize and develop new ones. This is where my overarching research interests reside.

Despite the maturity of catalysis as a scientific field,[4] no unifying “theory of catalysis” yet exists off which catalysts can be directly and rationally engineered at the experimental level—especially within the context of their eventual usage in industrial-scale chemical reactors. Great strides have been made in a posteriori rationalization of lab-scale experimental results, and a plethora of phenomena have been shown to be important to observed catalysis, but experiments are nonetheless seldom designed based on theoretical predictions. A properly formulated theory of catalysis should provide testable predictions while enabling scale up to the industrial reactor scale. In essence, it should map synthesis protocols and experimentally tunable parameters to reaction rates, selectivities, and yields. Without this, tackling climate change through the development of novel chemical technologies will be slowed by the continued necessity of a guess-and-check methodology and on-site optimizations.

The long-term goal of my research group is to develop such a theory of catalysis, enabling the design and interpretation of practical catalysis experiments on real catalysts to accelerate progress toward a green energy future. By leveraging quantum chemistry, advanced statistical mechanics, microkinetics, data science, and supercomputing power, we will perform advanced modeling of chemical transformations that connect molecular and global kinetic phenomena to the reactor scale (i.e., multiscale kinetic modeling). As a computational chemical engineer, my collaborators and I have utilized and developed specialized methodologies for describing non-idealized chemical systems undergoing reaction at catalytic surfaces.[5],[6],[7] These specialized methodologies can be used to extract the relevant information needed to produce what I believe will be the foundation of a true theory of catalysis.[8] This foundation is based on a holistic incorporation of not just enthalpy and local entropy driving forces, but also global enthalpy and entropy—an acknowledgement that observed catalysis is an ensemble phenomenon. I will show how global entropy is directly connected to the activity coefficients of surface-bound species and the availability of various distributions and types of sites.

[1] The White House: Statements and Releases. FACT SHEET: President Biden Sets 2030 Greenhouse... April 22, 2021. Website. Accessed June 29, 2021.

[2] United States Environmental Protection Agency. Sources of Greenhouse Gas Emissions. Website. Accessed June 29, 2021.

[3] Grand View Research. Catalyst Market Size & Share, Industry Report, 2020-2027. July 2020. Website. Accessed June 29, 2021.

[4] Wisniak, J. The History of Catalysis. From the Beginning to Nobel Prizes. Educación Química 2010, 21, 60-69.

[5] Hensley, A.J.R.; Collinge, G. et al. Guiding the design of oxidation-resistant Fe-based... Journal of Chemical Physics. 2021, 145, 17, 174709.

[6] Collinge G. et al. Effect of Collective Dynamics and Anharmonicity on Entropy... ACS Catalysis. 2020, 10, 16, 9236–9260.

[7] Collinge G. et al. Formulation of Multicomponent Lattice Gas Model Cluster Expansions...J. of Physical Chemistry C. 2020, 124, 5, 2923-2938.

[8] Collinge G. et al. Rate Expressions in Mean Field Microkinetic Models Incorporating Multiple Types of Active Sites. ACS Catalysis. 2021. (submitted)