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Automated and high-throughput reactivity analysis in homogeneous catalysis: The deactivation complexity of Mn(I) hydrogenation catalysts

Hashemi, A. (author)

In this thesis, I highlighted a number of projects aimed at developing and testing new simulation methods for studying complex reactive systems, with a particular emphasis on simulation strategies based on the concept of bonding graphs. These mathematical structures provide useful tools for a variety of algorithms developed over the last few...

doctoral thesis 2023

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Elucidating deactivation of titania-supported cobalt Fischer-Tropsch catalysts under simulated high conversion conditions

van Koppen, L.M. (author), Dugulan, A.I. (author), Leendert Bezemer, G. (author), Hensen, Emiel J.M. (author)

The study of titania-supported cobalt nanoparticles is relevant for industrial Fischer-Tropsch synthesis (FTS). Herein, we report about various deactivation pathways of cobalt supported on P25 titania (cobalt loading 2–8 wt%) under simulated high conversion conditions using in situ Mössbauer spectroscopy. A fraction of metallic cobalt was...

journal article 2023

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Sintering and carbidization under simulated high conversion on a cobalt-based Fischer-Tropsch catalyst; manganese oxide as a structural promotor

van Koppen, L.M. (author), Dugulan, A.I. (author), Hensen, Emiel J.M. (author), Bezemer, G. Leendert (author)

The commercial application of cobalt-based Fischer-Tropsch synthesis (FTS) suffers from catalyst deactivation. One of the main deactivation mechanisms under industrial conditions is sintering. In this work, we explored the role of manganese oxide as a structural promoter against sintering in a carbon nanofiber supported cobalt model catalyst....

journal article 2022

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High Stability of Methanol to Aromatic Conversion over Bimetallic Ca,Ga-Modified ZSM-5

Liu, C. (author), Uslamin, E. (author), Khramenkova, E. (author), Sireci, Enrico (author), Ouwehand, Lucas T.L.J. (author), Ganapathy, S. (author), Kapteijn, F. (author), Pidko, E.A. (author)

The production of valuable aromatics and the rapid catalyst deactivation due to coking are intimately related in the zeolite-catalyzed aromatization reactions. Here, we demonstrate that these two processes can be decoupled by promoting the Ga/HZSM-5 aromatization catalyst with Ca. The resulting bimetallic catalysts combine high selectivity to...

journal article 2022

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Deactivation pathways in methane upgrading catalysis

Franz, R.P.M. (author)

The abundance of methane has led to a strong interest to use methane as a feedstock in the chemical industry. One of the main challenges is the initial activation of the methane molecule. In this thesis, heterogeneous catalysts for two different methane conversion processes are investigated. Firstly, the deactivation of supported Ni catalysts...

doctoral thesis 2021

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Impact of Promoter Addition on the Regeneration of Ni/Al₂O₃ Dry Reforming Catalysts

Franz, R.P.M. (author), Pinto, D. (author), Uslamin, E. (author), Urakawa, A. (author), Pidko, E.A. (author)

Industrial-scale reforming of methane is typically carried out with an excess of oxidant to suppress coking of the catalyst. On the other hand, many academic studies on dry reforming employ a CO₂/CH₄ ratio of unity to quickly observe coking which can be reduced by adding a catalyst promoter. In this work, Ni/Al<sub>2<...

journal article 2021

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Challenges for the utilization of methane as a chemical feedstock

Franz, R.P.M. (author), Uslamin, E. (author), Pidko, E.A. (author)

The abundance of methane has led to a strong interest to use methane as a feedstock in the chemical industry. One of the main challenges is the initial activation of the methane molecule. This has resulted in the development of several different approaches to utilize methane, some more developed than others. In this work the current status of...

review 2021

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Role of surface carboxylate deposition on the deactivation of cobalt on titania Fischer-Tropsch catalysts

Gonugunta, P. (author), Dugulan, A.I. (author), Bezemer, G. Leendert (author), Brück, E.H. (author)

Operando spectroscopic techniques (Diffusive Reflective Infrared Fourier-Transform and Mössbauer emission spectroscopy) were combined to investigate the role of oxygenates deposition on deactivation of cobalt on titania Fischer-Tropsch catalysts at high pressure. Clear formation of carboxylates was seen for catalysts prepared via both...

journal article 2021

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Dry reforming of methane to test passivation stability of Ni/ Al₂O₃ catalysts

Franz, R.P.M. (author), Tichelaar, F.D. (author), Uslamin, E. (author), Pidko, E.A. (author)

Catalyst passivation refers to the formation of a protective oxide layer on the active metal particles that prevents their oxidation when exposed to air. Common passivation procedures, when applied to Ni/ Al2O3 catalysts, typically result in a significant decrease of the overall Ni surface area and, accordingly, the catalytic activity....

journal article 2021

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Metal-ligand cooperative activation of HX (X=H, Br, OR) bond on Mn based pincer complexes

Krieger, A.M. (author), Sinha, V. (author), Kalikadien, A.V. (author), Pidko, E.A. (author)

Reversible dissociation of H−X bond (M−L+H−X→M(X)-L(H); (Formula presented.)) is an important step during pre-activation, catalysis and possible deactivation of acid-base cooperative pincer based transition metal catalysts (M−L). Herein we carried out a high-throughput computational investigation of the thermodynamic stability of different...

journal article 2021

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Operando Modeling of Multicomponent Reactive Solutions in Homogeneous Catalysis: From Non-standard Free Energies to Reaction Network Control

Kuliaev, P. (author), Pidko, E.A. (author)

Optimization and execution of chemical reactions are to a large extend based on experience and chemical intuition of a chemist. The chemical intuition is rooted in the phenomenological Le Chatelier's principle that teaches us how to shift equilibrium by manipulating the reaction conditions. To access the underlying thermodynamic parameters...

journal article 2019

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Revealing Lattice Expansion of Small-Pore Zeolite Catalysts during the Methanol-to-Olefins Process Using Combined Operando X-ray Diffraction and UV-vis Spectroscopy

Goetze, Joris (author), Yarulina, I. (author), Gascon, Jorge (author), Kapteijn, F. (author), Weckhuysen, Bert M. (author)

In small-pore zeolite catalysts, where the size of the pores is limited by eight-ring windows, aromatic hydrocarbon pool molecules that are formed inside the zeolite during the Methanol-to-Olefins (MTO) process cannot exit the pores and are retained inside the catalyst. Hydrocarbon species whose size is comparable to the size of the zeolite...

journal article 2018

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Computational insights into the catalytic role of the base promoters in ester hydrogenation with homogeneous non-pincer-based Mn-P,N catalyst

Liu, C. (author), van Putten, R. (author), Kulyaev, Pavel O. (author), Filonenko, G.A. (author), Pidko, E.A. (author)

The reaction mechanism of ester hydrogenation catalyzed by a bidentate aminophosphine ligated manganese catalyst was studied by DFT calculations. Particular emphasize was placed on the role of the alkoxide base additives. The presence of such basic promoters as KO^tBu can improve the catalyst activity by lowering the activation...

journal article 2018

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Deactivation kinetics of solid acid catalyst with laterally interacting protons

Sengar, A. (author), Van Santen, Rutger A. (author), Steur, E. (author), Kuipers, J.A.M. (author), Padding, J.T. (author)

journal article 2018

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Insights into the Activity and Deactivation of the Methanol-to-Olefins Process over Different Small-Pore Zeolites As Studied with Operando UV-vis Spectroscopy

Goetze, Joris (author), Meirer, Florian (author), Yarulina, I. (author), Gascon, Jorge (author), Kapteijn, F. (author), Ruiz-Martínez, Javier (author), Weckhuysen, Bert M. (author)

The nature and evolution of the hydrocarbon pool (HP) species during the Methanol-to-Olefins (MTO) process for three small-pore zeolite catalysts, with a different framework consisting of large cages interconnected by small eight-ring windows (CHA, DDR, and LEV) was studied at reaction temperatures between 350 and 450 °C using a combination...

journal article 2017

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Metal–Organic Framework Mediated Cobalt/Nitrogen-Doped Carbon Hybrids as Efficient and Chemoselective Catalysts for the Hydrogenation of Nitroarenes

Sun, X. (author), Olivos Suarez, A.I. (author), Oar-Arteta Gonzalez, L. (author), Rozhko, E. (author), Osadchii, D. (author), Bavykina, A.V. (author), Kapteijn, F. (author), Gascon, Jorge (author)

A Co@N-doped carbon (Co@ NC) hybrid was synthesized by thermal decomposition of the metal–organic framework (MOF) ZIF-67 under N2 atmosphere. These hybrid materials exhibit outstanding catalytic activity and chemoselectivity for the conversion of a wide range of substituted nitroarenes to their corresponding anilines under relatively mild...

journal article 2017

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High-temperature Fischer-Tropsch synthesis over FeTi mixed oxide model catalysts: Tailoring activity and stability by varying the Ti/Fe ratio

Santos, Vera P. (author), Borgers, Liam (author), Sartipi, Sina (author), van der Linden, B. (author), Dugulan, A.I. (author), Chojecki, A (author), Davidian, T (author), Ruitenbeek, M (author), Meima, GR (author), Kapteijn, F. (author), Makkee, M. (author), Gascon, Jorge (author)

tA series of Fe-Ti mixed oxide model catalysts containing different Ti/Fe ratios were synthesized andapplied as catalysts for the High Temperature Fischer-Tropsch reaction (HTFTS). XRD, H2-TPR and in situMössbauer and XAFS spectroscopy were applied to evaluate the role of Ti on the physical and chemicalproperties of Fe within the mixed metal...

journal article 2017

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Towards Maximum Utilization of Remained Bandwidth in Defected NoC Links

Chen, C. (author), Fu, Yaowen (author), Cotofana, S.D. (author)

To maximize the utilization of the available networks-on-chip (NoCs) link bandwidth, partially faulty links with low fault level should be utilized while heavily defected (HD) links should be deactivated and dealt with by means of a fault tolerant routing algorithm. To reach this target, we make the following contributions in this paper: 1) we...

journal article 2017

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Hydride transfer versus deprotonation kinetics in the isobutane−propene alkylation reaction: A computational study

Liu, Chong (author), Van Santen, Rutger A. (author), Poursaeidesfahani, A. (author), Vlugt, T.J.H. (author), Pidko, Evgeny A. (author), Hensen, Emiel J M (author)

The alkylation of isobutane with light alkenes plays an essential role in modern petrochemical processes for the production of high-octane gasoline. In this study we have employed periodic DFT calculations combined with microkinetic simulations to investigate the complex reaction mechanism of isobutane–propene alkylation catalyzed by zeolitic...

journal article 2017

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Selective Coke Combustion by Oxygen Pulsing During Mo/ZSM-5-Catalyzed Methane Dehydroaromatization

Kosinov, Nikolay (author), Coumans, Ferdy J A G (author), Uslamin, Evgeny (author), Kapteijn, F. (author), Hensen, Emiel J M (author)

Non-oxidative methane dehydroaromatization is a promising reaction to directly convert natural gas into aromatic hydrocarbons and hydrogen. Commercialization of this technology is hampered by rapid catalyst deactivation because of coking. A novel approach is presented involving selective oxidation of coke during methane dehydroaromatization...

journal article 2016