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Designing the Protocols for Programmable Ammonia Catalysis

Manoj, Arjun [Johns Hopkins Univ., Baltimore, MD (United States)] (ORCID:0009000801598338)·Psarellis, Yorgos M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)]·Wittreich, Gerhard R. [Univ. of Delaware, Newark, DE (United States)]·Kavousanakis, Michail E. [National Technical Univ. of Athens (Greece)]·Dauenhauer, Paul J. [Univ. of Minnesota, Minneapolis, MN (United States)]·Kevrekidis, Ioannis G. [Johns Hopkins Univ., Baltimore, MD (United States)]
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Abstract

Programmable catalysis can provide a more energy-efficient and cost-effective route to enhancing commercial ammonia production, a key process in the advancement of renewable energy technologies and the manufacture of fertilizers and basic chemicals. This work explores the computational discovery of optimal forcing protocols to drive such dynamic catalysis models. By employing matrix-free time-stepper methods, coupled with an optimization approach, that integrates Bayesian optimization with a Bayesian continuation strategy to efficiently discover the periodic steady states of such periodically forced systems, we enable the discovery of complex optimal catalyst strain waveforms, while ensuring robust solver convergence. We demonstrate the flexibility of our approach to discover optimized forcing protocols under varying physical constraints on strain modulation or other catalyst operating parameters. We show that these can have a temporal structure more complex than simple step functions. In order to detect undesirable catalytic loops that may correlate with overall reduced performance, we perform a study using graph-theoretical analysis to investigate the dynamics of catalytic kinetic networks formed.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYammonia catalysiscatalytic loopsgraph-theoretic analysisprogrammable catalysiswaveform optimization

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Manoj, Arjun [Johns Hopkins Univ., Baltimore, MD (United States)] (ORCID:0009000801598338), Psarellis, Yorgos M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)], Wittreich, Gerhard R. [Univ. of Delaware, Newark, DE (United States)], Kavousanakis, Michail E. [National Technical Univ. of Athens (Greece)], Dauenhauer, Paul J. [Univ. of Minnesota, Minneapolis, MN (United States)], Kevrekidis, Ioannis G. [Johns Hopkins Univ., Baltimore, MD (United States)]. 2026-06-02. Designing the Protocols for Programmable Ammonia Catalysis. https://doi.org/10.1021/acscatal.5c08350

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