scholarly journals In Situ X-ray Absorption of Co/Mn/TiO2Catalysts for Fischer−Tropsch Synthesis

2004 ◽  
Vol 108 (41) ◽  
pp. 16201-16207 ◽  
Author(s):  
Fernando Morales ◽  
Frank M. F. de Groot ◽  
Pieter Glatzel ◽  
Evgueni Kleimenov ◽  
Hendrik Bluhm ◽  
...  
Keyword(s):  
Tropsch Synthesis ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis ◽  
X Ray ◽  
X Ray Absorption

scholarly journals In situ X-Ray Absorption of Co/Mn/TiO2 Catalysts for Fischer—Tropsch Synthesis.

ChemInform ◽  
2004 ◽  
Vol 35 (50) ◽  
Author(s):  
Fernando Morales ◽  
Frank M. F. de Groot ◽  
Pieter Glatzel ◽  
Evgueni Kleimenov ◽  
Hendrik Bluhm ◽  
...  
Keyword(s):  
Tropsch Synthesis ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis ◽  
X Ray ◽  
X Ray Absorption

scholarly journals Use of in situ Mossbauer Spectroscopy and X-Ray Diffraction Techniques for the Characterization of Activated Fe-Ce Catalysts Employed in Fischer-Tropsch Synthesis

2008 ◽  
Vol 1 (1) ◽  
pp. 64-70 ◽  
Author(s):  
F. J. Perez-Alonso ◽  
M. Ojeda ◽  
T. Herranz ◽  
J. M. Gonzalez-Carballo ◽  
J. L.G. Fierro ◽  
...  
Keyword(s):  
Mössbauer Spectroscopy ◽  
Mossbauer Spectroscopy ◽  
Tropsch Synthesis ◽  
X Ray Diffraction ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis ◽  
X Ray ◽  
Mößbauer Spectroscopy

Co-Promoted Cu/ZnO Catalysts for Fischer-Tropsch Synthesis

2017 ◽  
Vol 266 ◽  
pp. 117-121
Author(s):  
Piyasak Akcaboot ◽  
Napat Kanokpornwasin ◽  
Monthida Raoarun ◽  
Patraporn Saiwattanasuk ◽  
Pinsuda Viravathana
Keyword(s):  
Tropsch Synthesis ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Fischer Tropsch ◽  
Edge Structure ◽  
Fischer Tropsch Synthesis ◽  
X Ray ◽  
Cu Foil ◽  
Co Precipitation ◽  
X Ray Absorption

Co-promoted Cu/ZnO catalysts were studied for Fischer-Tropsch synthesis (FTS). All catalysts were prepared by the co-precipitation method, having the mass ratio of Co:Cu:Zn=0 (unpromoted), 0.05, 0.5:1:1, and characterized by X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), including X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). From XRD and XAS, the results confirmed the phase transformation of CuO to Cu foil and Co3O4 to Co foil in Co-promoted catalysts after reduction. After FTS reaction testing, the Co-promoted catalysts showed the decrease in methanol selectivity of 15 and 1.6% for 0.05Co-Cu/ZnO and 0.5Co-Cu/ZnO, respectively, and the increase in C5-C15 selectivity during 30 h of reaction.

scholarly journals X-ray absorption, X-ray diffraction and electron microscopy study of spent cobalt based catalyst in semi-commercial scale Fischer–Tropsch synthesis

2014 ◽  
Vol 479 ◽  
pp. 59-69 ◽  
Author(s):  
Nikolaos E. Tsakoumis ◽  
Roya Dehghan-Niri ◽  
Magnus Rønning ◽  
John C. Walmsley ◽  
Øyvind Borg ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Tropsch Synthesis ◽  
X Ray Diffraction ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis ◽  
X Ray ◽  
Commercial Scale ◽  
X Ray Absorption

scholarly journals In Situ X-ray Raman Scattering Spectroscopy of the Formation of Cobalt Carbides in a Co/TiO2 Fischer–Tropsch Synthesis Catalyst

ACS Catalysis ◽  
2021 ◽  
pp. 809-819
Author(s):  
José G. Moya-Cancino ◽  
Ari-Pekka Honkanen ◽  
Ad M. J. van der Eerden ◽  
Ramon Oord ◽  
Matteo Monai ◽  
...  
Keyword(s):  
Raman Scattering ◽  
Tropsch Synthesis ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis ◽  
Raman Scattering Spectroscopy ◽  
X Ray

scholarly journals Fischer–Tropsch Synthesis: Effect of the Promoter’s Ionic Charge and Valence Level Energy on Activity

Reactions ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 408-426
Author(s):  
Mirtha Z. Leguizamón León Ribeiro ◽  
Joice C. Souza ◽  
Muthu Kumaran Gnanamani ◽  
Michela Martinelli ◽  
Gabriel F. Upton ◽  
...  
Keyword(s):  
Tropsch Synthesis ◽  
Orbital Energy ◽  
Level Energy ◽  
Ionic Charge ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis ◽  
X Ray ◽  
Temperature Programmed ◽  
Similar Ionic Radius

In this contribution, we examine the effect of the promoter´s ionic charge and valence orbital energy on the catalytic activity of Fe-based catalysts, based on in situ synchrotron X-ray powder diffraction (SXRPD), temperature-programmed-based techniques (TPR, TPD, CO-TP carburization), and Fischer–Tropsch synthesis catalytic testing studies. We compared the promoting effects of K (a known promoter for longer-chained products) with Ba, which has a similar ionic radius but has double the ionic charge. Despite being partially “buried” in a crystalline BaCO3 phase, the carburization of the Ba-promoted catalyst was more effective than that of K; this was primarily due to its higher (2+) ionic charge. With Ba2+, higher selectivity to methane and lighter products were obtained compared to the K-promoted catalysts; this is likely due to Ba´s lesser capability of suppressing H adsorption on the catalyst surface. An explanation is provided in terms of a more limited mixing between electron-filled Ba2+ 5p and partially filled Fe 3d orbitals, which are expected to be important for the chemical promotion, as they are further apart in energy compared to the K+ 3p and Fe 3d orbitals.

Elucidation of The Influence of Cu Promoter on Carburization Prior to Iron-Based Fischer-Tropsch Synthesis: an In situ X-Ray Diffraction Study

ChemCatChem ◽  
2018 ◽  
Vol 11 (2) ◽  
pp. 715-723 ◽  
Author(s):  
Xiaodong Sun ◽  
Xingwu Liu ◽  
Jinjia Liu ◽  
Yurong He ◽  
Junqing Yin ◽  
...  
Keyword(s):  
Diffraction Study ◽  
Tropsch Synthesis ◽  
X Ray Diffraction ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis ◽  
X Ray ◽  
Iron Based

scholarly journals On the Cobalt Carbide Formation in a Co/TiO2 Fischer–Tropsch Synthesis Catalyst as Studied by High-Pressure, Long-Term Operando X-ray Absorption and Diffraction

ACS Catalysis ◽  
2021 ◽  
pp. 2956-2967
Author(s):  
Ilse K. van Ravenhorst ◽  
Adam S. Hoffman ◽  
Charlotte Vogt ◽  
Alexey Boubnov ◽  
Nirmalendu Patra ◽  
...  
Keyword(s):  
High Pressure ◽  
Tropsch Synthesis ◽  
Carbide Formation ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis ◽  
X Ray ◽  
Cobalt Carbide ◽  
X Ray Absorption

Cu/ZnO Catalysts for Enhancing the Methanol Selectivity in Fischer-Tropsch Synthesis

2015 ◽  
Vol 659 ◽  
pp. 206-210
Author(s):  
Passakorn Kongkinka ◽  
Kittima Chatrewongwan ◽  
Patraporn Saiwattanasuk ◽  
Pinsuda Viravathana
Keyword(s):  
Structural Changes ◽  
Product Distribution ◽  
Tropsch Synthesis ◽  
Catalyst Stability ◽  
Fischer Tropsch ◽  
Edge Structure ◽  
Fischer Tropsch Synthesis ◽  
Methanol Production ◽  
X Ray ◽  
X Ray Absorption

Cu/ZnO catalysts were studied to enhance the methanol selectivity in Fischer-Tropsch synthesis (FTS). By knowing that the methanol production from syngas (CO/H2) accelerated the crystallization of Cu and ZnO and led to the deactivation of the catalysts, a small amount of iron added to the catalyst could improve the catalyst stability by suppressing the crystallization of Cu and ZnO. The promotional effects of iron on the textural properties, reduction behavior, and structural changes of the Cu-based FTS catalysts were investigated by X-ray diffraction (XRD), X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). Their catalytic activity was measured at 10 bar and 190°C with H2/CO ratio of 2 and the FTS products were analyzed by GC. The product distribution was presented in terms of methanol, C1, C2-C4, and C5+ selectivity.

XAS Study on Calcination Effect of Silica Supported Cobalt Catalysts for Fischer-Tropsch Synthesis

2012 ◽  
Vol 608-609 ◽  
pp. 1413-1418
Author(s):  
Siwaruk Chotiwan ◽  
Waritsara Bungmek ◽  
Sanya Prangsri-Aroon ◽  
Pinsuda Viravathana
Keyword(s):  
Performance Testing ◽  
Tropsch Synthesis ◽  
Cobalt Catalysts ◽  
Fischer Tropsch ◽  
Edge Structure ◽  
Fischer Tropsch Synthesis ◽  
X Ray ◽  
Supported Cobalt Catalysts ◽  
Methane Selectivity ◽  
X Ray Absorption

The precalcined and calcined silica supported cobalt catalysts at 15, 20, and 25%Co were investigated by X-ray Absorption Spectroscopy (XAS) including the X-ray absorption near edge structure (XANES) and the extended X-ray absorption fine structure (EXAFS). The results showed the phase of Co(NO3)2.6H2O in all precalcined catalysts, which corresponded to the XRD measurement. When increasing the amount of cobalt in the precalcined catalysts, there was the presence of ordered Co(NO3)2.6H2O phase. After calcination in Ar at 600°C for 6 h, the Co3O4phase was presented in all calcined catalysts. For the catalytic performance testing, the selected 20%Co/Aerosil_wi_calcined catalyst was reduced at 450°C in H2and operated at 190°C with a total pressure of 10 bar and H2/CO flow rate of 20:10 ml/min for Fischer-Tropsch synthesis. After reaction testing, the used 20%Co/Aerosil_wi catalyst showed the main phase of Co3O4. The result showed high methane selectivity at the beginning of reaction. By increasing of reaction time, the methane selectivity tended to decrease, whereas the C2-C4and C5+selectivity was increased.

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