Porous Metal Oxides as Catalysts

2012 ◽  
Vol 1446 ◽  
Author(s):  
Boxun Hu ◽  
Christopher Brooks ◽  
Eric Kreidler ◽  
Steven L. Suib
Keyword(s):  
Co Hydrogenation ◽  
Porous Metal ◽  
Cobalt Catalysts ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Gas Chromatograph ◽  
Mesoporous Catalysts ◽  
Co Conversion ◽  
Liquid Products ◽  
Porous Metal Oxides

ABSTRACTPorous CoO/Mn2O3 Fischer-Tropsch (F-T) catalysts have been studied in CO hydrogenation. These CoO/Mn2O3 catalysts have been synthesized by incipient wetness impregnation method. These mesoporous catalysts have pore diameters of 2-25 nm and a surface area of 9.0 m2/g. The gas and liquid products have been analyzed by an online gas chromatograph. The solid products were characterized by gas chromatograph-mass spectroscopy. These microsize cobalt catalysts exhibit good activity with 72.1% CO conversion and they are very stable in a 48 h stream test at 280ºC. The selectivity to paraffins is above 95%. Few wax products were synthesized with a yield of less than 2%. The size effects of the cobalt catalysts have been studied by scanning electron microscopy.

On efficiency of vanadium-oxide promoter in cobalt Fischer – Tropsch catalysts

2021 ◽  
Vol 1 (1-2) ◽  
pp. 15
Author(s):  
Elham Yaghoobpour ◽  
Yahya Zamani ◽  
Saeed Zarrinpashne ◽  
Akbar Zamaniyan
Keyword(s):  
Vanadium Oxide ◽  
Active Sites ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Bet Surface Area ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Fischer Tropsch ◽  
Co Conversion ◽  
Loading Amount

Promoters and their loading amount have crucial roles in cobalt Fischer – Tropsch catalysts. In this regard, the effects of vanadium oxide (V2O5) as a proposed promoter for Co catalyst supported on TiO2 have been investigated. Three catalysts with 0, 1, and 3 wt.% of V2O5 promoter loading are prepared by the incipient wetness impregnation method, and characterized by the BET surface area analyzer, XRD, H2-TPR, and TEM techniques. The fixed-bed reactor was employed for their evaluations. It was found that the catalyst containing 1 wt.% V2O5 has the best performance among the evaluated catalysts, demonstrating remarkable selectivity: 92 % C5+ and 5.7 % CH4, together with preserving the amount of CO conversion compared to the unpromoted catalyst. Furthermore, it is reported that the excess addition of V2O5 promoter (> 1 wt.%) in the introduced catalyst leads to the detrimental effect on the CO conversion and C5+ selectivity, mainly owing to diminished active sites by V2O5 loading.

scholarly journals Alumina Coated Silica Nanosprings (NS) Support Based Cobalt Catalysts for Liquid Hydrocarbon Fuel Production From Syngas

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1810
Author(s):  
Abdulbaset Alayat ◽  
Elena Echeverria ◽  
Farid Sotoudehniakarani ◽  
David N. Mcllroy ◽  
Armando G. McDonald
Keyword(s):  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Fixed Bed ◽  
Chemical Properties ◽  
Hydrocarbon Fuel ◽  
Liquid Hydrocarbon ◽  
Cobalt Catalysts ◽  
Impregnation Method ◽  
X Ray ◽  
Co Conversion

The effects of Al2O3 coating on the performance of silica nanospring (NS) supported Co catalysts for Fischer–Tropsch synthesis (FTS) were evaluated in a quartz fixed-bed microreactor. The Co/NS-Al2O3 catalysts were synthesized by coating the Co/NS and NS with Al2O3 by an alkoxide-based sol-gel method (NS-Al-A and NS-Al-B, respectively) and then by decorating them with Co. Co deposition was via an impregnation method. Catalysts were characterized before the FTS reaction by the Brunauer–Emmett–Teller (BET) method, X-ray diffraction, transmission electron microscopy, temperature programmed reduction, X-ray photoelectron spectroscopy, differential thermal analysis and thermogravimetric analysis in order to find correlations between physico-chemical properties of catalysts and catalytic performance. The products of the FTS were trapped and analyzed by GC-TCD and GC-MS to determine the CO conversion and reaction selectivity. The Al2O3 coated NS catalyst had a significant affect in FTS activity and selectivity in both Co/NS-Al2O3 catalysts. A high CO conversion (82.4%) and Σ > C6 (86.3%) yield were obtained on the Co/NS-Al-B catalyst, whereas the CO conversion was 62.8% and Σ > C6 was 58.5% on the Co/NS-Al-A catalyst under the same FTS experimental condition. The Co/NS-Al-A catalyst yielded the aromatic selectivity of 10.2% and oxygenated compounds.

scholarly journals Effect of Pre-Treatment Conditions on the Activity and Selectivity of Cobalt-Based Catalysts for CO Hydrogenation

Reactions ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 258-274
Author(s):  
Nothando C. Shiba ◽  
Xinying Liu ◽  
Diane Hildebrandt ◽  
Yali Yao
Keyword(s):  
High Selectivity ◽  
Co Hydrogenation ◽  
Hydrogenation Reaction ◽  
Catalyst Design ◽  
Cobalt Catalysts ◽  
Incipient Wetness Impregnation ◽  
Liquid Hydrocarbons ◽  
Treatment Conditions ◽  
Lower Activation ◽  
Pre Treatment

We investigated the effect of pre-treatment conditions on the activity and selectivity of cobalt catalysts for Fischer–Tropsch synthesis (FTS) by varying both the reduction atmosphere and the reduction temperature. Catalysts supported on SiO2, Al2O3, and TiO2, prepared via incipient wetness impregnation, were evaluated, and activation temperatures in the range 250–350 °C were considered. Activation with syngas led to a better product selectivity (low CH4, high selectivity to liquid hydrocarbons, and low paraffin to olefin ratio (P/O)) than the catalysts reduced in H2 at lower activation temperatures. The CoxC species suppressed the hydrogenation reaction, and it is hypothesised that this resulted in the high selectivity of olefins observed for the syngas pre-treated catalysts. On the basis of the experimental results, we postulated that a synergistic effect between Co0 and CoxC promotes the production of the long chain hydrocarbons and suppresses the formation of CH4. In addition, for systems aimed at producing lower olefins, syngas activation is recommended, and for the FTS plants that focus on maximising the production of higher molecular weight products, H2 activation might be considered. These results provide insights for the future FTS catalyst design and for target product-driven operations.

scholarly journals Catalytic CO Methanation over Mesoporous ZSM5 with Different Metal Promoters

2019 ◽  
Vol 14 (1) ◽  
pp. 228 ◽  
Author(s):  
Lee Peng Teh ◽  
Sugeng Triwahyono ◽  
Aishah Abdul Jalil ◽  
Herma Dina Setiabudi ◽  
Muhammad Arif Abdul Aziz
Keyword(s):  
Catalytic Activity ◽  
High Surface ◽  
High Surface Area ◽  
Xrd Analysis ◽  
Metallic Phase ◽  
High Catalytic Activity ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Co Methanation ◽  
Co Conversion

The carbon monoxide methanation has possessed huge potential as an effective method to produce synthetic natural gas (SNG). The basic requirements such as high catalytic activity at low temperatures (<500 °C) and high stability throughout all temperatures is needed for an ideal methanation catalysts. The ultimate goal of the study is to examine the influential of different metal promoters towards catalytic properties and catalytic CO methanation performance. A series of metal promoters (Rh, Co, Pd and Zn) mesoporous ZSM5 were synthesized using an incipient-wetness impregnation method and evaluated for catalytic CO methanation. XRD analysis showed that only metal oxides and no metallic phase of Rh, Co, Pd, and Zn were observed. The nitrogen physisorption analysis showed that mZSM5 possessed high surface area and micro-mesoporosity with intra- and interparticle pores. FESEM analysis illustrated that mZSM5 had typical coffin-type morphology and Rh metal dispersed on the surface of the support was confirmed by EDX analysis. Moreover, Rh (CO conversion = 95%, CH4 yield = 82%) and Co (CO conversion = 91%, CH4 yield = 71%) promoters showed significant improvement in CO methanation. On the other hand, Pd (CO conversion = 18%, CH4 yield = 12%) and Zn (CO conversion = 10%, CH4 yield = 9%) promoters had only low benefit to the CO methanation. This study affirmed that the catalytic activity of CO methanation was influenced by the variation in the type of metal loading due to different nature of metallic phases and their synergistic interaction with the supporting material. Copyright © 2019 BCREC Group. All rights reservedReceived: 15th November 2018; Revised: 16th January 2019; Accepted: 17th January 2019; Available online: 25th January 2019; Published regularly: April 2019How to Cite: Teh, L.P., Triwahyono, S., Jalil, A.A., Setiabudi, H.D., Aziz, M.A.A. (2019). Catalytic CO Methanation over Mesoporous ZSM5 with Different Metal Promoters. Bulletin of Chemical Reaction Engineering & Catalysis, 14 (1): 228-237 (doi:10.9767/bcrec.14.1.3618.228-237)Permalink/DOI: https://doi.org/10.9767/bcrec.14.1.3618.228-237 

The Role of Catalytic Site Deposition on Cobalt Catalysts Supported on Carbon Nanotubes for Fisher-Trospch Synthesis

2012 ◽  
Vol 10 (1) ◽  
Author(s):  
Venkateswara Rao Surisetty ◽  
Eva Epelde ◽  
Mariane Trépanier ◽  
Janusz Kozinski ◽  
Ajay K. Dalai
Keyword(s):  
Carbon Nanotubes ◽  
Particle Deposition ◽  
Catalytic Site ◽  
Operating Conditions ◽  
Cobalt Catalysts ◽  
Incipient Wetness Impregnation ◽  
Fischer Tropsch ◽  
Co Conversion ◽  
Catalytic Sites

Abstract The influence of the catalytic site deposition on Fischer-Tropsch synthesis was investigated on cobalt catalysts supported on carbon nanotubes. The catalysts were prepared using incipient wetness impregnation by controlling the deposition of catalytic sites on either the inner or the outer surfaces of nanotubes. The catalysts were characterized extensively and the reaction was performed at similar operating conditions. The in-10Co/CNT catalyst showed better CO conversion compared to the out-10Co/CNT catalyst at all reaction temperatures. An improvement on the catalyst performance was demonstrated in the case of particle deposition inside the pores of the nanotubes with higher C5+ and C2-C4 selectivity.

scholarly journals Surface Structure and Catalytic Performance of Ni-Fe Catalyst for Low-Temperature CO Hydrogenation

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Fanhui Meng ◽  
Pengzhan Zhong ◽  
Zhong Li ◽  
Xiaoxi Cui ◽  
Huayan Zheng
Keyword(s):  
Low Temperature ◽  
Iron Content ◽  
Co Hydrogenation ◽  
Catalytic Performance ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Synthetic Natural Gas ◽  
Fe Catalyst ◽  
Ni Species ◽  
Shift Reaction

Catalysts 16NixFe/Al2O3(xis 0, 1, 2, 4, 6, 8) were prepared by incipient wetness impregnation method and the catalytic performance for the production of synthetic natural gas (SNG) from CO hydrogenation in slurry-bed reactor were studied. The catalysts were characterized by BET, XRD, UV-Vis DRS, H2-TPR, CO-TPD, and XPS, and the results showed that the introduction of iron improved the dispersion of Ni species, weakened the interaction between Ni species and support and decreased the reduction temperature and that catalyst formed Ni-Fe alloy when the content of iron exceeded 2%. Experimental results revealed that the addition of iron to the catalyst can effectively improve the catalytic performance of low-temperature CO methanation. Catalyst 16Ni4Fe/Al2O3with the iron content of 4% exhibited the best catalytic performance, the conversion of CO and the yield of CH4reached 97.2% and 84.9%, respectively, and the high catalytic performance of Ni-Fe catalyst was related to the property of formed Ni-Fe alloy. Further increase of iron content led to enhancing the water gas shift reaction.

scholarly journals Tungsten Oxide-Modified SSZ-13 Zeolite as an Efficient Catalyst for Ethylene-To-Propylene Reaction

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 553
Author(s):  
Mansurbek Urol ugli Abdullaev ◽  
Sungjune Lee ◽  
Tae-Wan Kim ◽  
Chul-Ung Kim
Keyword(s):  
Tungsten Oxide ◽  
Fixed Bed ◽  
Acid Sites ◽  
Fixed Bed Reactor ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Efficient Catalyst ◽  
X Ray ◽  
Propylene Selectivity ◽  
Temperature Programmed

Among the zeolitic catalysts for the ethylene-to-propylene (ETP) reaction, the SSZ-13 zeolite shows the highest catalytic activity based on both its suitable pore architecture and tunable acidity. In this study, in order to improve the propylene selectivity further, the surface of the SSZ-13 zeolite was modified with various amounts of tungsten oxide ranging from 1 wt% to 15 wt% via a simple incipient wetness impregnation method. The prepared catalysts were characterized with several analysis techniques, specifically, powder X-ray diffraction (PXRD), Raman spectroscopy, temperature-programmed reduction of hydrogen (H2-TPR), temperature-programmed desorption of ammonia (NH3-TPD), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and N2 sorption, and their catalytic activities were investigated in a fixed-bed reactor system. The tungsten oxide-modified SSZ-13 catalysts demonstrated significantly improved propylene selectivity and yield compared to the parent H-SSZ-13 catalyst. For the tungsten oxide loading, 10 wt% loading showed the highest propylene yield of 64.9 wt%, which was 6.5 wt% higher than the pristine H-SSZ-13 catalyst. This can be related to not only the milder and decreased strong acid sites but also the diffusion restriction of bulky byproducts, as supported by scanning transmission electron microscopy-energy dispersive X-ray spectroscopy (STEM-EDS) observation.

Effects of Cu and K Promoters on the Catalytic Performance of Iron-Based Nanocatalyst for Fischer-Tropsch Synthesis

2013 ◽  
Vol 832 ◽  
pp. 15-20 ◽  
Author(s):  
Sara Faiz Hanna Tasfy ◽  
Noor Asmawati Mohd Zabidi ◽  
Duvvuri Subbarao
Keyword(s):  
Atmospheric Pressure ◽  
Fixed Bed ◽  
Space Velocity ◽  
Catalytic Performance ◽  
Reactant Ratio ◽  
Impregnation Method ◽  
Fischer Tropsch ◽  
Heavy Hydrocarbons ◽  
Co Conversion ◽  
Iron Based

Iron-based nanocatalyst was prepared via impregnation method on SiO2 support. The effects of promoters, namely, K and Cu, on the physical properties and catalytic performance in FTS have been investigated. The FTS performance of the synthesized nanocatalysts was examined in a fixed-bed microreactor at temperature of 523K, atmospheric pressure, 1.5 reactant ratio (H2/CO) and space velocity of 3L/g-cat.h. In FTS reaction, Cu promoter resulted in a lower CO conversion and C5+ hydrocarbons selectivity but higher selectivity to the lighter hydrocarbons (C1-C4) comparedto those obtained using the K promoter. Higher CO conversion (28.9%) and C5+ hydrocarbons selectivity (54.4%) were obtained using K as a promoter compared to that of Cu promoter. However, the K-promoted nanocatalyst resulted in a lower CO conversion but higher selectivity of the heavy hydrocarbons (C5+) compared to those obtained using the un-promoted nanocatalyst.

Vapor-phase Oxidation of Cyclohexane over Supported Fe-Mn Catalysts: In-Situ DRIFTS studies

2021 ◽  
Author(s):  
Vijendra Kumar Yadav ◽  
Taraknath Das
Keyword(s):  
Surface Area ◽  
Raman Spectra ◽  
Vapor Phase ◽  
Oxide Catalysts ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
In Situ Drifts ◽  
Mn Oxide ◽  
Phase Oxidation

Alumina-supported Fe-Mn oxide catalysts were synthesized by the incipient wetness impregnation method. The catalysts were characterized by using various characterization techniques such as surface area, XRD, H2-TPR, and Raman spectra...

Porous Metal Oxides and Composites with Ferroic Properties

2012 ◽  
Vol 638 (10) ◽  
pp. 1577-1577 ◽  
Author(s):  
Stefanie Haffer ◽  
Christian Lüder ◽  
Stefan Ebbinghaus ◽  
Roberto Köferstein ◽  
Till Walther ◽  
...  
Keyword(s):  
Metal Oxides ◽  
Porous Metal ◽  
Porous Metal Oxides ◽  
Ferroic Properties
Sign in / Sign up

Export Citation Format

Share Document