Searched for: subject%3A%22deactivation%22
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Vijverberg, Lotte (author)
Alkaline water electrolysis emerges as a promising technology for green hydrogen production, playing a significant role in global decarbonization. Nickel-based electrodes are widely used in alkaline water electrolysis due to their excellent catalytic properties for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER)....
master thesis 2024
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van Koppen, L.M. (author), Dugulan, A.I. (author), Hensen, Emiel J.M. (author), Bezemer, G. Leendert (author)
Cobalt oxidation is a relevant deactivation pathway of titania-supported cobalt catalysts used in Fischer-Tropsch synthesis (FTS). To work towards more stable catalysts, we studied the effect of the surface area of the titania support and noble metal promotion on cobalt oxidation under simulated high conversion conditions. Mössbauer...
journal article 2024
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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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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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van Koppen, L.M. (author), Dugulan, A.I. (author), Leendert Bezemer, G. (author), Hensen, Emiel J.M. (author)
Understanding the deactivation mechanism of cobalt-based Fischer-Tropsch catalysts is of significant practical importance. Herein, we explored the role of manganese as a structural promoter on silica-supported cobalt nanoparticles under simulated high CO conversion conditions, i.e., high relative humidity. The structural changes in cobalt...
journal article 2023
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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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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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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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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 CO<sub>2</sub>/CH<sub>4</sub> 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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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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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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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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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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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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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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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<sup>t</sup>Bu can improve the catalyst activity by lowering the activation...
journal article 2018
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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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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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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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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
Searched for: subject%3A%22deactivation%22
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