Fischer–Tropsch synthesis over carbon nanotubes supported cobalt catalysts in a fixed bed reactor: Influence of acid treatment

Trépanier, Mariane; Tavasoli, Ahmad; Dalai, Ajay K.; Abatzoglou, Nicolas

doi:10.1016/j.fuproc.2008.10.012

Cited by 142 publications

(107 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As reported in other study, at high temperature, olefins are preferentially hydrogenated, and chain propagation is suppressed, which explains the increase of methane selectivity (Dry, 1981;Jacobs et al, 2002). Our previous studies also show that % CO conversion strongly depends on the reaction temperature (Tavasoli et al, 2008;Trépanier et al, 2009a). Indeed, increasing the FTS reaction temperature increases the mobility of hydrogen on the catalyst surface which leads, among several other effects, to higher % CO conversion.…”

Section: Fts Catalyst Activity and Selectivitysupporting

confidence: 71%

“…Figure 4 shows the TPR spectra of the calcined Ru.5K.0016K(Co15) catalyst compared to Co15, Ru0.5(Co15), and K.0016(Co15) catalysts from our previous work (Trépanier et al, 2009a). The first peak of the TPR profile is typically assigned to the reduction of Co 3 O 4 to CoO, although a fraction of the peak likely comprises the reduction of the larger, bulk-like CoO species to Co 0 (Tavasoli et al, 2009).…”

Section: Catalyst Characterisation Resultsmentioning

confidence: 97%

“…As reported in our previous work, the particles inside the tubes were fairly uniform and in size range of 3-9 nm in accordance with the average inner diameter of the CNTs, whereas those on the outer surface have grown to about 8-15 nm. The CNT channels restricted the growth of the particles inside the tubes (Trépanier et al, 2009a(Trépanier et al, ,b, 2010.…”

Section: Catalyst Characterisation Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Kinetics study on cnt‐supported RuKCo FTS catalyst in a fixed bed reactor

et al. 2011

Self Cite

View full text Add to dashboard Cite

The rate of syngas (H 2 /CO) consumption over a RuKCo/CNT Fischer-Tropsch synthesis (FTS) catalyst was measured in a fixed bed microreactor at 210-225 • C, 2-3.5 MPa, H 2 /CO feed molar ratios of 1-2.5, and gas hourly space velocity (GHSV) range of 2700-3600 h −1 . The data have been used to model the kinetics of the FTS reactions within the range of the studied conditions. One empirical power law model and four semi-empirical kinetic models based on Langmuir-Hinshelwood-type equation have been evaluated. The best fitting was obtained with the equation:similar to that proposed by Brötz et al. The estimated activation energy (E = 80-85 kJ/mol) is lower than that is reported in the literature. The validity of these results are restricted to fixed beds with the given catalyst in the tested conversion regime.Le taux de consommation de gaz de synthèse (H 2 /CO) sur un catalyseur de synthèse de Fischer-Tropsch (SFT) RuKCo/CNT aété mesuré dans un microréacteurà lit fixeà 210à 225 • C, 2à 3,5 MPa, des rapports molaires d'alimentation H 2 /CO de 1à 2,5 et une portée de vitesse horaire des gaz de 2700à 3600 h −1 . Les données ontété utilisées pour modeler la cinétique des réactions de la SFT au sein de la portée des conditionsétudiées. Un modèle de loi exponentielle empirique et quatre modèles cinétiques semi-empiriques fondés sur uneéquation de type Langmuir-Hinshelwood ontétéévalués. Ce qui correspondait le mieuxétait obtenu avec l'équation suivante:(1 + 7.2 × 10 −2 P 0.72semblableà celle proposée par Brötz et coll. L'énergie d'activation estimée (E = 80-85 KJ/mol) est inférieureà celle rapportée par la littérature. Ces résultats sont associés aux propriétés physiques et chimiques uniques des supports de nanotubes de carbone qui réduisent l'énergie d'activation du catalyseur.

show abstract

Section: Fts Catalyst Activity and Selectivitysupporting

confidence: 71%

Section: Catalyst Characterisation Resultsmentioning

confidence: 97%

Section: Catalyst Characterisation Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Kinetics study on cnt‐supported RuKCo FTS catalyst in a fixed bed reactor

et al. 2011

Self Cite

View full text Add to dashboard Cite

show abstract

“…In order to maximize the catalytic activity measured by CO conversion during FTS, prior catalyst reduction is paramount because the active species in Co-containing samples are construed to be metallic (Co • ) in nature. Some authors have asserted that the highest CO conversions in FTS are attributed to higher Co reducibility [33], while the oxidation of the Co metal leads to catalyst deactivation [21]. Figure 4 presents the XRD patterns of the fresh Co metal injected into the plasma, which comprised two phases as analysed by RQA: 62% having face centred cubic (FCC) structure, and 38% hexagonal closed packing (HCP) structure [7].…”

Section: Xrd and Rqa Analysismentioning

confidence: 99%

Effect of CO Concentration on the α-Value of Plasma-Synthesized Co/C Catalyst in Fischer-Tropsch Synthesis

Aluha

Abatzoglou

2017

Catalysts

Self Cite

View full text Add to dashboard Cite

Abstract:A plasma-synthesized cobalt catalyst supported on carbon (Co/C) was tested for Fischer-Tropsch synthesis (FTS) in a 3-phase continuously-stirred tank slurry reactor (3-φ-CSTSR) operated isothermally at 220 • C (493 K), and 2 MPa pressure. Initial syngas feed stream of H 2 :CO ratio = 2 with molar composition of 0.6 L/L (60 vol %) H 2 and 0.3 L/L (30 vol %) CO, balanced in 0.1 L/L (10 vol %) Ar was used, flowing at hourly space velocity (GHSV) of 3600 cm 3 ·h −1 ·g −1 of catalyst. Similarly, other syngas feed compositions of H 2 :CO ratio = 1.5 and 1.0 were used. Results showed~40% CO conversion with early catalyst selectivity inclined towards formation of gasoline (C 4 -C 12 ) and diesel (C 13 -C 20 ) fractions. With prolonged time-on-stream (TOS), catalyst selectivity escalated towards the heavier molecular-weight fractions such as waxes (C 21+ ). The catalyst's α-value, which signifies the probability of the hydrocarbon-chain growth was empirically determined to be in the range of 0.85-0.87 (at H 2 :CO ratio = 2), demonstrating prevalence of the hydrocarbon-chain propagation, with particular predisposition for wax production. The inhibiting CO effect towards FTS was noted at molar H 2 :CO ratio of 1.0 and 1.5, giving only~10% and~20% CO conversion respectively, although with a high α-value of 0.93 in both cases, which showed predominant production of the heavier molecular weight fractions.

show abstract

“…Moreover, the narrow inner CNT channels diameter (9-10 nm) hinders the small cobalt crystallites growth inside the tube (31) . It is reported that the TEM images of the CNT supported catalyst showed the smaller cobalt crystallites are lying inside the CNT channels and the larger ones are on the outside (32)(33)(34) . The EDX analysis (image entire in Fig.…”

Section: Transmission Electron Microscopy (Tem)mentioning

confidence: 99%

Hydrotreating of Egyptian Heavy Vacuum Gas Oil over Co-Mo/Carbon Nanotube Catalyst

2016

Egypt. J. Chem.

View full text Add to dashboard Cite

HE HYDROTREATING catalyst development is an essential ……..factor to produce clean fuels. The catalytic performance of CoMoS/CNT on Hydrotreating of the Egyptian heavy vacuum gas oil was investigated. Firstly the CNT was functionalized with concentrated HNO 3 . The Mo and Co wt% were loaded on CNT by impregnation methods. The catalyst was characterized by X-ray diffraction, Raman Spectroscopy, TEM, and BET. The hydrotreating experiments were conducted on autoclave reactor at various operating conditions of o C, pressure (20-60) bar, time (2-6) h and cat/oil ratio of 1:75, 33 and 10. The result indicated that the CoMoS/CNT was an efficient for the hydrotreating process. Also, the hydride-sulfurization (HDS) enhanced with increasing catalyst/oil ratio. Moreover, Results revealed that the optimum condition (temperature 350 o C, Pressure 40 bar, catalyst/oil ratio of 1:75 for 2 hr, was chosen.Additionally, even at low catalyst ratio of 1:75 an acceptable HDS% of 77.1 was achieved.Keywords: Hydrotreatment, Heavy vacuum gas oil (HVGO), Carbon nanotubes and CoMo/CNT.Due to economical and pollution control aspects, up 2010 the world legislations limited the sulfur content in fuels to <15 ppm (1)(2)(3)(4) . In order to meet this challenge, Nemours efforts to develop the hydrotreatment process, responsible for S and N removal, were potentially developed. Commercially, the MoS promoted by Co or Ni and supported on γ-Al 2 O 3 are the most active catalysts for hydrotreating process (5)(6) . The Co-Mo based catalyst is highly selective for HDS whereas NiMo based catalyst is more selective for hydrodenitrogenation (HDN) and hydrogenation. consequently, Ni-Mo based catalysts consumes higher hydrogen than Co-Mo based catalysts for the same extent of HDS with identical feed (7) . Despite the good thermal and textural properties and the high metal dispersion ability of γ-Al 2 O 3 (8) , it forms a strong metal-support interaction (9) .This interaction prohibits the complete metals sulfidation which decline the required active sites (10) .

show abstract

Fischer–Tropsch synthesis over carbon nanotubes supported cobalt catalysts in a fixed bed reactor: Influence of acid treatment

Cited by 142 publications

References 19 publications

Kinetics study on cnt‐supported RuKCo FTS catalyst in a fixed bed reactor

Kinetics study on cnt‐supported RuKCo FTS catalyst in a fixed bed reactor

Effect of CO Concentration on the α-Value of Plasma-Synthesized Co/C Catalyst in Fischer-Tropsch Synthesis

Hydrotreating of Egyptian Heavy Vacuum Gas Oil over Co-Mo/Carbon Nanotube Catalyst

Contact Info

Product

Resources

About