Article
Chemistry, Physical
Tobias F. Kimpel, Jin-Xun Liu, Wei Chen, Robert Pestman, Emiel J. M. Hensen
Summary: Through IR spectroscopy and DFT calculations, it has been discovered that in the Fischer-Tropsch reaction, Mn promotes a silica-supported Co catalyst with a MnO layer covering the Co surface, activating adsorbed CO through reaction with an oxygen vacancy. This results in higher activity, higher CHx coverage, increased C5+ selectivity, and decreased CH4 selectivity. Increasing pressure amplifies the selectivity differences. However, above around 4 bar, the addition of Mn decreases C5+ selectivity, possibly due to its promotion of C-O bond dissociation but not chain growth. Migration of formed monomers for chain growth on the Co surface may be hindered by high CO coverage, especially at high pressure.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Physical
Renjie Liu, Denis Leshchev, Eli Stavitski, Mitchell Juneau, Jane N. Agwara, Marc D. Porosoff
Summary: Research on utilizing CO2 as a C-1 feedstock for the synthesis of chemicals and fuels shows that the selectivity of catalysts is strongly linked to the Si/Al ratio and the method of introducing the K promoter.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Chemistry, Physical
Minhua Zhang, Haipeng Yu, Yingzhe Yu, Lingtao Wang
Summary: This study investigates the catalytic behavior of cobalt carbide nanoprisms in the Fischer-Tropsch to olefins (FTO) process. The results show that C-O scission and CHO insertion play important roles in ethylene formation and carbon chain growth, while the selectivity towards oxygenates is suppressed.
JOURNAL OF CATALYSIS
(2022)
Article
Energy & Fuels
Hong Du, Miao Jiang, Hejun Zhu, Chuande Huang, Ziang Zhao, Wenda Dong, Wei Lu, Tao Liu, Z. Conrad Zhang, Yunjie Ding
Summary: A highly efficient activated carbon supported cobalt based catalyst for Fischer-Tropsch synthesis was prepared and activated through multistep processes, exhibiting superior performance in CO conversion and CH4 selectivity compared to conventional catalysts. The catalyst's excellent performance was attributed to its increased amount of active sites and dominant hcp metallic cobalt phases. Further improvements in catalytic performance were achieved by adjusting the content of hcp metallic cobalt phase stacking through proper treatment conditions in the multistep activation method.
Article
Chemistry, Physical
Mikhail Shipilin, David Degerman, Patrick Lomker, Christopher M. Goodwin, Gabriel L. S. Rodrigues, Michael Wagsta, Joergen Gladh, Hsin-Yi Wang, Andreas Stierle, Christoph Schlueter, Lars G. M. Pettersson, Anders Nilsson, Peter Amann
Summary: In this study, the effect of pressure, temperature, time, and gas feed composition on the growth dynamics of iron-carbon phases was investigated. The details of iron surface carburization and product formation under realistic conditions were revealed using a combination of experimental and theoretical approaches. This research provides important insights into the relationship between the catalyst's surface and the reaction.
Article
Chemistry, Physical
Mikhail Shipilin, David Degerman, Patrick Loemker, Christopher M. Goodwin, Gabriel L. S. Rodrigues, Michael Wagstaffe, Jorgen Gladh, Hsin-Yi Wang, Andreas Stierle, Christoph Schlueter, Lars G. M. Pettersson, Anders Nilsson, Peter Amann
Summary: This study investigates the detailed mechanism of carbide formation on iron-based catalysts and the effect of reaction conditions on the catalyst surface state through experiments and theoretical calculations.
Article
Engineering, Environmental
Haipeng Yu, Lingtao Wang, Yingzhe Yu, Guochao Yang, Minhua Zhang
Summary: In this study, a comprehensive reaction network analysis on the Co2C(1 1 1) facet was conducted using first-principles-based microkinetics modeling. Pathways for generating methane, ethane, ethylene, acetaldehyde, ethanol, and C3+ products were identified, and the predicted product distribution matched experimental observations. The competition between hydrocarbon and oxygenate formation was analyzed, and the elementary reaction steps controlling product selectivity were quantitatively determined.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Luke M. van Koppen, A. Iulian Dugulan, G. Leendert Bezemer, Emiel J. M. Hensen
Summary: This study explored the role of manganese as a structural promoter on silica-supported cobalt nanoparticles under high CO conversion conditions. It was found that adding manganese oxide enhanced the dispersion of cobalt but resulted in cobalt silicate formation. Without manganese, the cobalt particles sintered and transformed into cobalt carbide.
JOURNAL OF CATALYSIS
(2023)
Article
Energy & Fuels
Dalia Liuzzi, Francisco J. Perez-Alonso, Sergio Rojas
Summary: Ru-Co/Al2O3 and Ru-Fe/Al2O3 catalysts prepared by reduction-deposition method exhibit high activity in Fischer-Tropsch Synthesis, showing different conversion rates and product selectivity. The interaction between Ru and Co in Ru-Co/Al2O3 enhances the activity, while Ru-Fe/Al2O3 displays superior initial performance but declines over time, with less enriched products compared to Ru/Al2O3.
Article
Chemistry, Physical
Jose G. Moya-Cancino, Ari-Pekka Honkanen, Ad M. J. van der Eerden, Ramon Oord, Matteo Monai, Iris ten Have, Christoph J. Sahle, Florian Meirer, Bert M. Weckhuysen, Frank M. F. de Groot, Simo Huotari
Summary: The study presents in situ experiments to investigate the formation of cobalt carbides during Fischer-Tropsch synthesis on a Co/TiO2 catalyst under relevant pressure and temperature conditions. X-ray Raman scattering (XRS) spectroscopy and X-ray diffraction (XRD) were used in combination to perform the experiments. The results indicate a change in the oxidation state of cobalt nanoparticles, leading to the formation of cobalt carbide (Co2C) during the FTS reaction.
Article
Chemistry, Applied
Nothando C. Shiba, Xinying Liu, Yali Yao
Summary: This paper provides a critical review of the recent achievements in direct carbon monoxide hydrogenation to light olefins, highlighting the influencing factors and catalyst mechanisms. It also outlines future research directions in this field.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Energy & Fuels
Nothando C. Shiba, Xinying Liu, Diane Hildebrandt, Huaping Mao, Yali Yao
Summary: Immobilized cobalt nanoparticles on SiO2 underwent hydrogenation-carburization-hydrogenation (H-C-H) treatment, leading to a 40% increase in CO conversion compared to standard treatment. The enhanced catalyst reducibility and dispersion of Co-hcp via Co2C intermediate resulted in high CH4 and olefin selectivity, potentially impacting liquid fuel selectivity. Nonetheless, this work provides valuable insights for future FTS catalyst design and synthetic fuel production.
Article
Chemistry, Multidisciplinary
Iris C. ten Have, Robin Y. van den Brink, Stephane C. Marie-Rose, Florian Meirer, Bert M. Weckhuysen
Summary: Gasification is a process that converts solid waste into gaseous feedstock. This study investigates the possibility of using waste gasification solid residue as a catalyst for producing light olefins. Experimental results show that the catalyst can convert biomass-derived syngas into methane and olefins.
Article
Chemistry, Physical
Amel Cydric Ghogia, Bruno F. Machado, Simon Cayez, Ange Nzihou, Philippe Serp, Katerina Soulantica, Doan Pham Minh
Summary: The chemistry between the Co precursor and the support during catalyst preparation has a crucial impact on the catalyst properties, while the CNT surface chemistry also influences the characteristics of the catalyst. The study found an inverse correlation between Co particle size and activity, highlighting the importance of precursor/support couple in the structure and performance of Co/CNT catalysts.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Physical
Luke M. van Koppen, A. Iulian Dugulan, G. Leendert Bezemer, Emiel J. M. Hensen
Summary: This study investigates the role of manganese oxide as a structural promoter against sintering in a carbon nanofiber supported cobalt model catalyst. The results show that steam accelerates the sintering of non-promoted metallic cobalt particles, while in the presence of manganese oxide, sintering is significantly reduced. However, some cobalt particles in close interaction with manganese oxide carburize under these conditions, resulting in lower catalytic activity.
JOURNAL OF CATALYSIS
(2022)
