Isomorphic titanium-substituted mesoporous SBA-16 as support for cobalt Fischer–Tropsch synthesis catalysts: Balance between dispersion and reduction

2021 ◽  
Author(s):  
Liang Wei ◽  
Jian Chen ◽  
Shuai Lyu ◽  
Chengchao Liu ◽  
Yanxi Zhao ◽  
...  

The delicate balance between dispersion and reduction of the Co-based Fischer–Tropsch synthesis catalyst is the golden key to enhancing catalytic performance, which highly depends on an optimized metal–support interaction. In...

2016 ◽  
Vol 6 (23) ◽  
pp. 8355-8363 ◽  
Author(s):  
Jing-Wen Yu ◽  
Wei-Zhen Li ◽  
Tao Zhang ◽  
Ding Ma ◽  
Ya-Wen Zhang

The high AFTS activity and C5+ selectivity of the serial Ru/TiO2 nanocatalysts were favoured by the increasing metallic Ru sites due to H2 reduction pretreatment and weak metal–support interaction.


2015 ◽  
Vol 5 (7) ◽  
pp. 3525-3535 ◽  
Author(s):  
Jae Min Cho ◽  
Chang Il Ahn ◽  
Changhyun Pang ◽  
Jong Wook Bae

The increased C2–C4selectivity on the Co/AlSBA-15 was mainly attributed to the formation of small cobalt particles with a stronger metal–support interaction on the outer surface acid sites of the AlSBA-15 due to a higher hydrophilicity of the Al-incorporated SBA-15.


Author(s):  
Moradian Amin ◽  
Bahadoran Farzad ◽  
Shirazi Laleh ◽  
Zamani Yahya

AbstractIn this study the effect of (0.1 %Ru, 0–10 % Zr) and (0.1 %Ru, 0–10 % Ce) promoters on dispersion, strong metal-support interaction and reduction behavior of cobalt-supported alumina catalyst in the Fischer-Tropsch synthesis was investigated. The synthesized catalysts were characterized by BET, XRD, ICP, TPR, XPS, and TEM techniques. The results show that addition of Ce to the catalyst leads to the shift of the TPR peaks to lower temperatures which expected that shows higher activity due to higher reducibility, but surprisingly due to SMSI effect results in the lower catalyst activity compared with the unpromoted catalyst. Also, there was a synergistic effect between Ce and Ru in the reduction behavior of Ru-Ce promoted catalyst. The other notable finding of this study was the improvement in the catalyst reducibility in the presence of Zr compared with the unpromoted one that equivalently means the higher catalyst activity. Comparison of the Zr-promoted with the Ce-promoted catalysts show that the former have higher catalyst activity than the latter due to higher acidity and SMSI effect in the presence of the Zr promoter. The C5selectivity of the 0.1Ru10Zr/15Co and 3Ce/15Co catalysts at low pressure have shown more than 50 % improvement compared to the unpromoted one. Based on the activity at atmospheric pressure; the unpromoted, 0.1Ru/15Co, 0.1Ru3Ce/15Co and 0.1Ru10Zr/15Co catalysts were selected for high pressure condition tests, in which the 0.1Ru10Zr/15Co catalyst shows the highest catalyst activity and heavier hydrocarbon selectivity.


ACS Catalysis ◽  
2020 ◽  
Vol 10 (21) ◽  
pp. 12967-12975
Author(s):  
Yaru Zhang ◽  
Xiong Su ◽  
Lin Li ◽  
Haifeng Qi ◽  
Chongya Yang ◽  
...  

Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 967
Author(s):  
Erling Rytter ◽  
Jia Yang ◽  
Øyvind Borg ◽  
Anders Holmen

The ratio between propene and propane (C3 o/p) during Fischer–Tropsch synthesis (FTS) has been analyzed based on both literature reports and experiments for five catalysts. The latter comprise four cobalt catalysts on γ-alumina with variations in pore sizes, and one catalyst on α-alumina. Overall variations include H2/CO feed ratio, residence time, water addition, transients between test conditions, CO conversion, cobalt particle size, promoter (Re), and support material. It was possible to rationalize all data based on secondary hydrogenation of olefins. In fact, it was deduced that olefins are dominating termination products in FTS, estimated to ca. 90% for C3, but that some paraffins most likely are also produced directly. Increased residence time and high H2/CO feed ratio favors olefin hydrogenation, while added water presumably displaces hydrogen on cobalt giving enhanced C3 o/p. High cobalt dispersion favors hydrogenation, as also promoted by Re. Effect of intraparticle diffusion is seen in transient periods; for example, as water is added or depleted. There is frequently positive correlation between C3 o/p and selectivity to longer chains; the latter expressed as C5+ selectivity, as both are sensitive to hydrogen activity. Some modifications, however, are needed due to the accepted volcano plot for C5+ selectivity with cobalt crystallite size. Titania as support shows unexpectedly low C3 o/p; probably due to SMSI (strong-metal-support-interaction).


2016 ◽  
Vol 6 (8) ◽  
pp. 2633-2646 ◽  
Author(s):  
M. J. Valero-Romero ◽  
S. Sartipi ◽  
X. Sun ◽  
J. Rodríguez-Mirasol ◽  
T. Cordero ◽  
...  

Deposition of pyrolytic carbon on the surface of mesoHZSM-5 improves the activity, C5–C9 selectivity and decreases CH4 selectivity by weakening cobalt-support interaction.


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