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Microkinetic modeling is a widely used tool in the domain of heterogeneous catalysis to gain valuable insights about the fundamental surface kinetics, crucial to designing improved catalysts. The development of a microkinetic model is a multi‐step process that demands expertise, a wide variety of experimental techniques, substantial computational resources, and extensive time and effort. In light of these challenges, automation within catalysis research is becoming increasingly important to allow exploration of a broader range of catalytic systems in a shorter timeframe. To this extent, a variety of digital tools and software have been developed to accelerate the development of microkinetic models. This work aims to highlight a selection of these tools that address the various challenges confronting the researchers in this field. These tools address diverse aspects, from the efficient storage of research data that allows easy retrieval and reuse, to the establishment of automated workflows that harness state‐of‐the‐art numerical solvers and algorithms that reduce manual effort. Through the use of automation, these aim to expedite and streamline the development and validation of models for catalytic systems, thereby reducing errors and increasing efficiency. [ABSTRACT FROM AUTHOR]

Modern research methods produce large amounts of scientifically valuable data. Tools to process and analyze such data have advanced rapidly. Yet, access to large amounts of high‐quality data remains limited in many fields, including catalysis research. Implementing the concept of FAIR data (Findable, Accessible, Interoperable, Reusable) in the catalysis community would improve this situation dramatically. The German NFDI initiative (National Research Data Infrastructure) aims to create a unique research data infrastructure covering all scientific disciplines. One of the consortia, NFDI4Cat, proposes a concept that serves all aspects and fields of catalysis research. We present a perspective on the challenging path ahead. Starting out from the current state, research needs are identified. A vision for a integrating all research data along the catalysis value chain, from molecule to chemical process, is developed. Respective core development topics are discussed, including ontologies, metadata, required infrastructure, IP, and the embedding into research community. This Concept paper aims to inspire not only researchers in the catalysis field, but to spark similar efforts also in other disciplines and on an international level. [ABSTRACT FROM AUTHOR]

This article, titled "Cover Feature: Interconnected Digital Solutions to Accelerate Modeling of the Reaction Kinetics in Catalysis," discusses the importance of microkinetic modeling in heterogeneous catalysis. The authors highlight the challenges involved in developing these models, including the need for expertise, experimental techniques, computational resources, and time. To address these challenges, automation is crucial in catalysis research. The article showcases various tools and software that expedite the creation of microkinetic models, aiming to accelerate model development, reduce errors, and enhance efficiency in exploring different catalytic systems. The authors emphasize the significance of automation in catalysis research for improved catalyst design. [Extracted from the article]

Abstract: The significance of gas-phase reactions in catalytic partial oxidation (CPOX) of isooctane at short contact times and high temperatures is studied experimentally and numerically to gain further understanding of hydrogen production by CPOX of logistic fuels for on-board applications. Special attention is given to the formation of coke precursors. CPOX of isooctane over a rhodium coated monolith with a molar inlet C/O ratio of 1.1 is used as reference case for a two-dimensional flow field description coupled with detailed surface and gas-phase reaction mechanisms. The results reveal catalyst coking and formation of coke precursors in the oxygen-free catalyst zone. Taking the product composition of the rich operated CPOX reactors (C/O=1.0−1.6) as inlet composition, homogeneous conversion in the gas-phase is studied in the temperature range from 873 to 1173K in a plug flow reactor. Conversion in the gas-phase is modeled by two detailed reaction mechanisms. Results show that most of the by-products and soot precursor species arise from unconverted fuel and not from additionally added hydrocarbons like ethylene. Both mechanisms well-predict all experimentally observed trends in gas-phase composition, both in axial reactor profiles and for different inlet compositions. The amount of soot precursors raises with increasing fuel feed corresponding to an increasing C/O ratio in CPOX experiments. [ABSTRACT FROM AUTHOR]

Abstract: Direct internal reforming in solid oxide fuel cell (SOFC) results in increased overall efficiency of the system. Present study focus on the chemical and electrochemical process in an internally reforming anode supported SOFC button cell running on humidified CH4 (3% H2 O). The computational approach employs a detailed multi-step model for heterogeneous chemistry in the anode, modified Butler–Volmer formalism for the electrochemistry and Dusty Gas Model (DGM) for the porous media transport. Two-dimensional elliptic model equations are solved for a button cell configuration. The electrochemical model assumes hydrogen as the only electrochemically active species. The predicted cell performances are compared with experimental reports. The results show that model predictions are in good agreement with experimental observation except the open circuit potentials. Furthermore, the steam content in the anode feed stream is found to have remarkable effect on the resulting overpotential losses and surface coverages of various species at the three-phase boundary. [Copyright &y& Elsevier]

Abstract: This work focuses on the development and improvement of numerical tools for the simulation of catalytic monolith reactors. These simulations cover detailed descriptions of reaction mechanisms, transport in gas-phase and washcoats, fluid flow in single channels, and the entire reactor. In DETCHEMMONOLITH, the concept of building a transient model of the monolith reactor by the calculation of steady-state solutions of representative channels has been improved. Thus, simulations with inlet conditions varying in space and time become feasible. Furthermore, reactors with alternating channel properties can be considered. Another extension concerns storage catalysts that accounts for transient surface coverages of the storage medium. As example, three numerical studies are shown: a catalytic combustion device with alternating active and inactive channels, a catalytic combustion monolith with spatially varying inlet conditions, and a NO x storage catalyst with alternating inlet conditions. [Copyright &y& Elsevier]

Front Cover: A Unified Research Data Infrastructure for Catalysis Research - Challenges and Concepts (ChemCatChem 14/2021) Keywords: GeCats; NFDI; NFDI4Cat; Catalysis Community; Digitalization; Research Data Management EN GeCats NFDI NFDI4Cat Catalysis Community Digitalization Research Data Management 3198 3198 1 07/30/21 20210721 NES 210721 B The Front Cover b illustrates the dynamics and complexity of catalysis. Indicated in the picture is a vision of integrating all research data along the catalysis value chain, from molecule to chemical process. [Extracted from the article]

Planar laser-induced fluorescence (PLIF) enables noninvasive in situ investigations of catalytic flow reactors. The method is based on the selective detection of two-dimensional absolute concentration maps of conversion-relevant species in the surrounding gas phase inside a catalytic channel. Exemplarily, the catalytic reduction of NO with hydrogen (2 NO+5 H2→2 H2O+2 NH3) is investigated over a Pt/Al2O3 coated diesel oxidation catalyst by NO PLIF inside an optically accessible channel reactor. Quenching-corrected 2D concentration maps of the NO fluorescence above the catalytic surface are obtained under both, nonreactive and reactive conditions. The impact of varying feed concentration, temperature, and flow velocities on NO concentration profiles are investigated in steady state. The technique presented has a high potential for a better understanding of interactions of mass transfer and surface kinetics in heterogeneously catalyzed gas-phase reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D modeling of an 86-particle fixed bed with CPOX and DRM chemistry. • ISAT and CA methods used to accelerate the calculation of reaction source terms. • CA method is simpler than other implementations of this acceleration technique. • ISAT and CA methods were added to DUO, which couples OpenFOAM and DETCHEM. • Speedup factors were 7x for CPOX and 35x for DRM, with acceptable calculation errors. Simulation of fixed-bed catalytic reactors is important for engineering industrial technologies. The large number of catalytically active surface faces makes the application of microkinetic models too time consuming for large 3D simulations that include fully resolved particle structures (e.g., ≫ 10′s of particles). Such simulations, though, are often required for small tube-to-particle diameter ratio configurations, where local flow effects are difficult to capture with 1D or 2D simulations. A common solution for speeding up reactive computational fluid dynamics (CFD) involves the use of chemistry acceleration methods, including In-Situ Adaptive Tabulation (ISAT) and Cell Agglomeration (CA). In the present contribution, DUO (DETCHEMTM + OpenFOAM coupling) CFD software has been extended to include ISAT and CA methods for surface reactions, in particular, using a CA method that is simpler than other implementations of this acceleration technique. Speedup factors and errors were tabulated for an 86 spherical particle 3D resolved fixed-bed reactor, considering the exothermic methane catalytic partial oxidation (CPOX) and the endothermic dry reforming of methane (DRM) chemistries. For CPOX, a speedup factor of ∼ 7x was achieved, while for DRM, a speedup of ∼ 35x was obtained, with both cases achieving an acceptable error in the solution. Although a tighter error tolerance with ISAT and CA is shown to reduce the overall calculation error, for some engineering situations this tradeoff in speedup and accuracy will be acceptable. Achieving usable results in around 0.5 – 2 h instead of around 20-hours (for these chemistries on this particular grid, run on a 400-core cluster) can vastly improve the feasibility of computational fluid dynamics for the analysis of fixed-bed catalytic reactors including microkinetics mechanisms. [ABSTRACT FROM AUTHOR]

The development of highly efficient engines with lower exhaust gas temperatures leads to new challenges for catalysts in the aftertreatment system. One option for overcoming this is a catalyst positioned in front of the turbocharger with an exposure to higher temperature and pressure. The impact of increased pressure and typical catalyst poisons on the catalytic performance of a state-of-the-art Cu-SSZ-13 catalyst has thus been studied during the selective catalytic reduction of NO x with NH 3 . Various reactions including NO/NH 3 oxidation, standard and fast SCR have been tested in a temperature range of 180–600 °C. Propene as representative for small hydrocarbons and SO 2 have been added under reaction conditions to analyze the direct influence at relevant reaction temperatures. An increased pressure resulted in a strikingly higher DeNOx-activity especially under Standard-SCR conditions, which was mainly due to higher NO oxidation to NO 2 in the gas phase and a higher residence time. Even though propene led to a temporary competition between SCR-reaction and propene oxidation, the small decrease in DeNOx-activity can be overcompensated by the higher pressure and temperature within a pre-turbine configuration with no need for regeneration steps. In contrast, SO 2 caused severe deactivation at low temperature but no influence at high temperature. Reactivation was not completely possible, which suggests some highly stable sulfur species. The higher pre-turbine temperature enables an earlier regeneration, showing a further advantage of pre-Turbo-SCR. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a detailed surface reaction mechanism for the decomposition of NH3 to H2 and N2 on a Ni surface. The mechanism is validated for temperatures ranging from 700 to 1500K and pressures from 5.3Pa to 100kPa. The activation energies for various elementary steps are calculated using the unity bond index-quadratic exponential potential (UBI-QEP) method. Sensitivity analysis is carried out to study the influence of various kinetic parameters on reaction rates. The NH3 decomposition mechanism is used to simulate SOFC button cell operating on NH3 fuel. [Copyright &y& Elsevier]

Abstract: A pseudo-transient numerical model is used for the simulation of a multi-functional catalytic plate reactor (CPR). The work mainly addresses the problems associated with on-board reforming for solid-oxide fuel cells. Heat management is achieved by indirectly coupling partial oxidation with reforming. Water management is achieved by partially recycling the anode stream from a solid-oxide fuel cell. The model uses detailed heterogeneous chemistry for reforming and oxidation reactions occurring on the catalyst beds. [ABSTRACT FROM AUTHOR]