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

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.

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The Effect of Aluminum Source on Performance of Beta-Zeolite as a Support for Hydrocracking Catalyst

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.13.3.2570.543-552 ◽

2018 ◽

Vol 13 (3) ◽

pp. 543

Author(s):

Mina Hadi ◽

Hamid Reza Aghabozorg ◽

Hamid Reza Bozorgzadeh ◽

Mohammad Reza Ghasemi

Keyword(s):

Fixed Bed ◽

Diffraction Method ◽

Acid Sites ◽

Fixed Bed Reactor ◽

Beta Zeolite ◽

Impregnation Method ◽

Gas Oil ◽

Hydrocracking Catalyst ◽

Silica Alumina ◽

Temperature Programmed

In this paper, three different kinds of aluminum sources (sodium aluminate, aluminum sulfate and aluminum isopropylate) were used for preparing of nano beta-zeolite. The as synthesized zeolites were mixed with the as prepared amorphous silica-alumina to produce the supports for hydrocracking catalyst. The prepared supports were used for preparation of NiMo/silica alumina-nano beta-zeolite by impregnation method. The influence of the aluminum source for preparation of beta-zeolite on the performance of the prepared catalysts has been studied. The samples were thoroughly characterized by X-Ray diffraction method (XRD), field emission-scanning electron microscopy (FE-SEM), N2 adsorption-desorption isotherms (BET), temperature programmed desorption (TPD) and temperature programmed reduction (TPR) methods. The catalysts performance was evaluated by vacuum gas oil (VGO) hydrocracking at 390 oC in a fixed bed reactor. The XRD patterns showed that the beta-zeolite samples obtained from the present methods were pure and highly crystalline and the crystal size of the prepared zeolites were in nanometer scale. Crystallite size of nano beta-zeolite synthesized by aluminum isopropylate [Al(iPrO)3] was smaller than those of prepared by the other aluminum sources. The catalyst containing this zeolite with higher surface area (231 m2/g) and more available acid sites (1.66 mmol NH3/g) possessed higher activity and selectivity to gas oil (71.9 %). Copyright © 2018 BCREC Group. All rights reservedReceived: 25th April 2018; Revised:22nd July 2018; Accepted: 29th July 2018How to Cite: Hadi, M., Aghabozorg, H.R., Bozorgzadeh, H.R., Ghasemi, M.R. (2018). The Effect of Aluminum Source on Performance of Beta-Zeolite as a Support for Hydrocracking Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 543-552 (doi:10.9767/bcrec.13.3.2570.543-552)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2570.543-552

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Effect of Operating Temperature, Pressure and Potassium Loading on the Performance of Silica-Supported Cobalt Catalyst in CO2 Hydrogenation to Hydrocarbon Fuel

Catalysts ◽

10.3390/catal9100807 ◽

2019 ◽

Vol 9 (10) ◽

pp. 807 ◽

Cited By ~ 3

Author(s):

Iloy ◽

Jalama

Keyword(s):

Photoelectron Spectroscopy ◽

Operating Temperature ◽

Fixed Bed ◽

Co2 Hydrogenation ◽

Fixed Bed Reactor ◽

Activation Process ◽

Operating Pressure ◽

Impregnation Method ◽

X Ray ◽

Temperature Programmed

Potassium (1–5 wt.%)-promoted and unpromoted Co/SiO2 catalysts were prepared by impregnation method and characterized by nitrogen physisorption, temperature-programmed reduction (TPR), CO2 temperature-programmed desorption (TPD), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques. They were evaluated for CO2 hydrogenation in a fixed bed reactor from 180 to 300 °C within a pressure range of 1–20 bar. The yield for hydrocarbon products other than methane (C2+) was found to increase with an increase in the operating temperature and went through a maximum of approximately 270 °C. It did not show any significant dependency on the operating pressure and decreased at potassium loadings beyond 1 wt.%. Potassium was found to enhance the catalyst ability to adsorb CO2, but limited the reduction of cobalt species during the activation process. The improved CO2 adsorption resulted in a decrease in surface H/C ratio, the latter of which enhanced the formation of C2+ hydrocarbons. The highest C2+ yield was obtained on the catalyst promoted with 1 wt.% of potassium and operated at an optimal temperature of 270 °C and a pressure of 1 bar.

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Influence of Sulfur-Containing Sodium Salt Poisoned V2O5–WO3/TiO2 Catalysts on SO2–SO3 Conversion and NO Removal

Catalysts ◽

10.3390/catal8110541 ◽

2018 ◽

Vol 8 (11) ◽

pp. 541 ◽

Cited By ~ 3

Author(s):

Haiping Xiao ◽

Chaozong Dou ◽

Hao Shi ◽

Jinlin Ge ◽

Li Cai

Keyword(s):

Photoelectron Spectroscopy ◽

No Reduction ◽

Catalytic Performance ◽

Acid Sites ◽

Impregnation Method ◽

So2 Oxidation ◽

Sodium Salts ◽

X Ray ◽

Temperature Programmed ◽

Physical Features

A series of poisoned catalysts with various forms and contents of sodium salts (Na2SO4 and Na2S2O7) were prepared using the wet impregnation method. The influence of sodium salts poisoned catalysts on SO2 oxidation and NO reduction was investigated. The chemical and physical features of the catalysts were characterized via NH3-temperature programmed desorption (NH3-TPD), H2-temperature programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FT-IR). The results showed that sodium salts poisoned catalysts led to a decrease in the denitration efficiency. The 3.6% Na2SO4 poisoned catalyst was the most severely deactivated with denitration efficiency of only 50.97% at 350 °C. The introduction of SO42− and S2O72− created new Brønsted acid sites, which facilitated the adsorption of NH3 and NO reduction. The sodium salts poisoned catalysts significantly increased the conversion of SO2–SO3. 3.6%Na2S2O7 poisoned catalyst had the strongest effect on SO2 oxidation and the catalyst achieved a maximum SO2–SO3-conversion of 1.44% at 410 °C. Characterization results showed sodium salts poisoned catalysts consumed the active ingredient and lowered the V4+/V5+ ratio, which suppressed catalytic performance. However, they increased the content of chemically adsorbed oxygen and the strength of V5+=O bonds, which promoted SO2 oxidation.

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Effect of CO2 partial pressure on dry reforming of ethanol for hydrogen production

International Journal of Innovative Research and Scientific Studies ◽

10.53894/ijirss.v1i1.3 ◽

2018 ◽

Vol 1 (1) ◽

pp. 6-10

Author(s):

Fahim Fayaz ◽

Ahmad Ziad Sulaiman ◽

Sharanjit Singh ◽

Sweeta Akbari

Keyword(s):

Partial Pressure ◽

Fixed Bed ◽

Dry Reforming ◽

Fixed Bed Reactor ◽

Bet Surface Area ◽

Impregnation Method ◽

X Ray Diffraction ◽

Co2 Partial Pressure ◽

Temperature Programmed ◽

Al2o3 Catalyst

The effect of CO2 partial pressure on ethanol dry reforming was evaluated over 5%Ce-10%Co/Al2O3 catalyst at = PCO2 = 20-50 kPa, PC2H5OH = 20 kPa, reaction temperature of 973 K under atmospheric pressure. The catalyst was prepared by using impregnation method and tested in a fixed-bed reactor. X-ray diffraction measurements studied the formation of Co3O4, spinel CoAl2O4 and CeO2, phases on surface of 5%Ce-10%Co/Al2O3 catalyst. CeO2, CoO and Co3O4 oxides were obtained during temperature–programmed calcination. Ce-promoted 10%Co/Al2O3 catalyst possessed high BET surface area of 137.35 m2 g-1. C2H5OH and CO2 conversions was improved with increasing CO2 partial pressure from 20-50 kPa whilst the optimal selectivity of H2 and CO was achieved at 50 kPa.

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

Kataliz v promyshlennosti ◽

10.18412/1816-0387-2021-1-2-15 ◽

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.

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What is the Effect of Promoter Loading on Alkalized Bimetallic Co-Mo Catalyst for Higher Alcohols Synthesis from Syngas?

Kataliz v promyshlennosti ◽

10.18412/1816-0387-2019-2-86-94 ◽

2019 ◽

Vol 19 (2) ◽

pp. 86-94

Author(s):

R. G. Moqadam ◽

A. Tavasoli ◽

M. Salimi

Keyword(s):

Fixed Bed ◽

Fixed Bed Reactor ◽

Incipient Wetness Impregnation ◽

Operating Pressure ◽

Impregnation Method ◽

Higher Alcohol Synthesis ◽

Higher Alcohol ◽

Alcohol Synthesis ◽

Higher Alcohols Synthesis ◽

Methanol Formation

Manganese and nickel co-modified K/Co/MoS2 catalysts supported on graphene were prepared by incipient wetness impregnation method for application in higher alcohol synthesis (HAS). All catalysts were characterized by X-ray diffraction (XRD), nitrogen adsorptiondesorption, temperature-programmed reduction (TPR) and transmission electron microscopy (TEM). The effect of promoters, as well as supports on higher alcohol synthesis production from syngas, was investigated in a fixed bed reactor. The process was performed with an molar ratio H2 : CO = 1 : 1, operating pressure and temperature of 4 MPa and 330 °C, respectively, and gas hourly space velocity (GHSV) 3.84 m3 (STP)/(kgcat.·h) as reaction conditions (STP – standard temperature and pressure). Results originated from practical works showed that the addition of Ni to the graphene-based catalyst increased HAS production and decreased methanol formation. The total alcohols space-time yield (STY) and alcohol selectivity on Ni/Mn/Co/Mo/K/graphene catalyst reached a maximum at 0.41 galc./(gcat.·h) and 63.51 %, respectively, which is higher than the same composition over alumina supported catalyst.

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Comparison of Cobalt Based Catalysts Supported on MWCNT and SBA-15 Supporters for Fischer-Tropsch Synthesis by Using Autoclave Type Reactor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.364.70 ◽

2011 ◽

Vol 364 ◽

pp. 70-75 ◽

Cited By ~ 1

Author(s):

Adkham Yakubov ◽

M.G. Kutty ◽

Pei Lee Siew ◽

Maizatul S. Shaharun ◽

S.B. Abd Hamid ◽

...

Keyword(s):

Electron Microscopy ◽

Multiwall Carbon Nanotubes ◽

Incipient Wetness Impregnation ◽

Impregnation Method ◽

Santa Barbara ◽

X Ray ◽

Transmission Electron ◽

Temperature Programmed ◽

Multiwall Carbon ◽

Autoclave Reactor

10 and 40 wt% Co/Multiwall Carbon Nanotubes (MWCNT) and 10 and 40 wt% Co/Santa Barbara Amorphous-15 (SBA-15) catalysts were prepared via incipient wetness impregnation method. It was characterized by Scanning Electron Microscopy, BET, X-ray Diffractometry (XRD), Transmission Electron Microscopy (TEM), Temperature-Programmed Reduction and H2Desorption. A 200 ml hastelloy autoclave reactor was implemented to see the performance of the catalysts. It was observed that the performance of 40 wt% Co/SBA-15 was higher that other catalysts in terms of production of longer chain paraffins.

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High Active Co/Mg1-xCex3+O Catalyst: Effects of Metal-Support Promoter Interactions on CO2 Reforming of CH4 Reaction

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.16.1.9969.97-110 ◽

2021 ◽

Vol 16 (1) ◽

pp. 97-110

Author(s):

Faris A. Jassim Al-Doghachi ◽

Diyar M. A. Murad ◽

Huda S. Al-Niaeem ◽

Salam H. H. Al-Jaberi ◽

Surahim Mohamad ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Fixed Bed ◽

Fixed Bed Reactor ◽

Dry Reforming Of Methane ◽

Precipitation Method ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Co2 Reforming Of Ch4 ◽

Temperature Programmed

Co/Mg1−XCe3+XO (x = 0, 0.03, 0.07, 0.15; 1 wt% cobalt each) catalysts for the dry reforming of methane (DRM) reaction were prepared using the co-precipitation method with K2CO3 as precipitant. Characterization of the catalysts was achieved by X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), X-ray photoelectron spectroscopy (XPS), temperature programmed reduction (H2-TPR), Brunauer–Emmett–Teller (BET), transmission electron microscopy (TEM), and thermal gravimetric analysis (TGA). The role of several reactant and catalyst concentrations, and reaction temperatures (700–900 °C) on the catalytic performance of the DRM reaction was measured in a tubular fixed-bed reactor under atmospheric pressure at various CH4/CO2 concentration ratios (1:1 to 2:1). Using X-ray diffraction, a surface area of 19.2 m2.g−1 was exhibited by the Co/Mg0.85Ce3+0.15O catalyst and MgO phase (average crystallite size of 61.4 nm) was detected on the surface of the catalyst. H2 temperature programmed reaction revealed a reduction of CoO particles to metallic Co0 phase. The catalytic stability of the Co/Mg0.85Ce3+0.15O catalyst was achieved for 200 h on-stream at 900 °C for the 1:1 CH4:CO2 ratio with an H2/CO ratio of 1.0 and a CH4, CO2 conversions of 75% and 86%, respectively. In the present study, the conversion of CH4 was improved (75%–84%) when conducting the experiment at a lower flow of oxygen (1.25%). Finally, the deposition of carbon on the spent catalysts was analyzed using TEM and Temperature programmed oxidation-mass spectroscopy (TPO-MS) following 200 h under an oxygen stream. Better anti-coking activity of the reduced catalyst was observed by both, TEM, and TPO-MS analysis. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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Influence of Nickel Loading on Reduced Graphene Oxide-Based Nickel Catalysts for the Hydrogenation of Carbon Dioxide to Methane

Catalysts ◽

10.3390/catal10050471 ◽

2020 ◽

Vol 10 (5) ◽

pp. 471

Author(s):

Nur Diyan Mohd Ridzuan ◽

Maizatul Shima Shaharun ◽

Kah Mun Lee ◽

Israf Ud Din ◽

Poppy Puspitasari

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

High Surface ◽

Nickel Catalysts ◽

Incipient Wetness Impregnation ◽

Impregnation Method ◽

Co2 Methanation ◽

X Ray ◽

Reduced Graphene ◽

Temperature Programmed

In this study, a series of novel nickel catalysts supported on reduced graphene oxide nanosheets (Ni/rGO) with Ni loadings of 10, 15 and 20 wt% were successfully synthesized via the incipient wetness impregnation method. The physicochemical properties of the catalysts and rGO support were thoroughly characterized by thermogravimetric analyser, X-ray diffraction, fourier-transform infrared spectroscopy, Raman spectroscopy, N2 adsorption-desorption, temperature programmed reduction, temperature programmed CO2 desorption and field emission scanning electron microscopy with energy dispersive X-ray spectroscopy. The properties of the catalysts are correlated to its catalytic activity for CO2 methanation which were investigated using three-phase slurry reactor at low temperature and pressure of 240 °C and 10 bar, respectively. Among the three catalysts of different Ni loading, Ni15/rGO shows the highest activity of 51% conversion of CO2 with total selectivity towards CH4. N2-physisorption and CO2-TPD analysis suggest that high catalytic performance of Ni15/rGO is attributed to the high surface area, strong basic sites and special support effect of rGO in anchoring the active metal.

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Synthesis and characterization of graphene oxide supported cobalt (II) tetrasulfophthalocyanine as an efficient heterogeneous nanocatalyst for mercaptans oxidation from gasoline

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424617500523 ◽

2017 ◽

Vol 21 (07n08) ◽

pp. 510-522 ◽

Cited By ~ 3

Author(s):

Kazem Motahari ◽

Hojatollah Ahmadi

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Fixed Bed ◽

Fixed Bed Reactor ◽

Incipient Wetness Impregnation ◽

X Ray ◽

Fcc Gasoline ◽

Ethyl Mercaptan ◽

Vis Spectroscopy ◽

Mercaptan Oxidation

In the present study, graphene oxide-supported cobalt (II) tetrasulfophthalocyanine (CoTsPc-GO) was synthesized using the incipient wetness impregnation assisted [Formula: see text]–[Formula: see text] assembling method. Applications for this material were investigated for ethyl mercaptan, [Formula: see text]-propyl mercaptan and [Formula: see text]-butyl mercaptan oxidation from fluid catalytic cracking (FCC) gasoline in a fixed bed reactor. The synthesized CoTsPc-GO catalysts were characterized using UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Raman spectroscopy analysis, field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDAX), thermogravimetric and differential thermal analysis (TGA-DTA), inductively coupled plasma optical emission spectroscopy (ICP-OES), and transmission electron microscopy (TEM). The effect of cobalt (II) tetrasulfophthalocyanine (CoTsPc) content (0–0.34 g), catalyst dosage (0.02–0.12 g) and temperature (30–40∘ C) on the performance of CoTsPc-GO catalysts were investigated during the Merox process. The stability and reusability of CoTsPc-GO catalyst for mercaptans oxidation were also tested. The obtained results revealed that the maximum mercaptan oxidation during the Merox process was obtained in CoTsPc-GO of 0.34 g, catalyst content of 0.1 g and a temperature of 40∘ C with ethyl mercaptan, [Formula: see text]-propyl mercaptan and [Formula: see text]-butyl mercaptan conversions of 99.9, 98.5 and 97.0%, respectively. The potential of CoTsPc-GO catalyst was investigated for further mercaptans oxidation. The results were compared to those obtained with an industrial impregnated active charcoal catalyst and a CoPc catalyst. The obtained results demonstrated the higher capability of CoTsPc-GO catalyst for mercaptans oxidation from FCC gasoline.

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