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

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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Effects of Platinum and Palladium Metals on Ni/Mg1-xZrxO Catalysts in the CO2 Reforming of Methane

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.13.2.1656.295-310 ◽

2018 ◽

Vol 13 (2) ◽

pp. 295 ◽

Cited By ~ 4

Author(s):

Faris Jasim Abdulridha Al-Doghachi

Keyword(s):

Photoelectron Spectroscopy ◽

Thermo Gravimetric Analysis ◽

Coke Formation ◽

Dry Reforming Of Methane ◽

Precipitation Method ◽

Cubic Phase ◽

Gravimetric Analysis ◽

Co2 Reforming ◽

X Ray ◽

Co2 Reforming Of Methane

Nickel, palladium, and platinum catalysts (1 wt.% each) supported on MgO and MgZrO to prepare Pt,Pd,Ni/Mg1-xZrxO catalysts (where x = 0, 0.03, 0.07, and 0.15), were synthesized by using co-precipitation method with K2CO3 as the precipitant. X-ray diffraction (XRD), X-ray fluorescence (XRF), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), transmission electron microscopy (TEM), H2-temperature programmed reduction (H2-TPR), and thermo gravimetric analysis (TGA) were employed to observe the characteristics of the prepared catalysts. The Pt,Pd,Ni/Mg0.85Zr0.15O showed the best activity in dry reforming of methane (DRM) with 99 % and 91 % for CO2 and CH4 conversions, respectively and 1.28 for H2/CO ratio at temperature 900 °C and 1:1 of CH4:CO2 ratio. The stability of Pt,Pd,Ni/Mg0.85Zr0.15O catalyst in the presence and absence of low stream 1.25 % oxygen was investigated. Carbon formation and amount in spent catalysts were examined by TEM and TGA in the presence of stream oxygen. The results showed that the amount of carbon was suppressed and negligible coke formation (less than 3 %) was observed. Several effects were observed with ZrO2 use as a promoter in the catalyst. Firstly, the magnesia cubic phase stabilized. Secondly, thermal stability and support for basicity increased. Thirdly, carbon deposition and the reducibility of Ni2+, Pd2+, and Pt2+ ions decreased. Copyright © 2018 BCREC Group. All rights reservedReceived: 25th October 2017; Revised: 2nd January 2018; Accepted: 18th January 2018; Available online: 11st June 2018; Published regularly: 1st August 2018How to Cite: Al-Doghachi, F.A.J. (2018). Effects of Platinum and Palladium Metals on Ni/Mg1-xZrxO Catalysts in the CO2 Reforming of Methane. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (2): 295-310 (doi:10.9767/bcrec.13.2.1656.295-310)

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Evolution of Copper Supported on Fe3O4 Nanorods for WGS Reaction

Catalysts ◽

10.3390/catal8100415 ◽

2018 ◽

Vol 8 (10) ◽

pp. 415 ◽

Cited By ~ 4

Author(s):

Lingjuan Ma ◽

Hongbin Ma ◽

Dawei Han ◽

Mingyue Qiu ◽

Yafei Guan ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Ambient Pressure ◽

Phase Evolution ◽

Precipitation Method ◽

X Ray Diffraction ◽

X Ray ◽

In Situ Xrd ◽

Wgs Reaction ◽

Transmission Electron ◽

Temperature Programmed

Rod-shaped Cu1Fe9Ox precursor was successfully prepared through an aqueous precipitation method. The shape and phase composition were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that Cu1Fe9Ox is composed of CuFe2O4 and Fe2O3. The reduction performance of Cu1Fe9Ox was studied by in situ XRD and H2 temperature-programmed reduction (H2-TPR). Cu/Fe3O4 nanorod catalyst is obtained through the controllable reduction of Cu1Fe9Ox nanorod, and the formed Cu/Fe3O4 nanorod catalyst does not have low-temperature water gas shift (WGS) activity, but exhibits high-temperature WGS reaction activity. Ambient pressure X-ray photoelectron spectroscopy (AP-XPS) studies showed that the main species of copper is Cu+ during the WGS reaction. The interaction between Cu and Fe3O4 rod and phase evolution of Cu species are quite different from Cu/Fe3O4 nanoparticles.

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Pd-Only Catalyst Modified by BaO with Co- Precipitation and Impregnation Methods towards the Methanol Fuel Emission Control

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.581-582.313 ◽

2012 ◽

Vol 581-582 ◽

pp. 313-316

Author(s):

Xue Qiao Zhang ◽

Zhi Xiang Ye ◽

Cheng Hua Xu ◽

Ming Zhao ◽

Yao Qiang Chen

Keyword(s):

Co Oxidation ◽

Photoelectron Spectroscopy ◽

Palladium Catalysts ◽

Active Species ◽

Precipitation Method ◽

Impregnation Method ◽

X Ray Diffraction ◽

X Ray ◽

Temperature Programmed ◽

Co Precipitation

Barium oxide was introduced to modify Palladium catalysts supported on CeO2–ZrO2-La2O3-Al2O3 (CZLA) by impregnation and co-precipitation. methods. Various techniques, including X-ray diffraction (XRD), H2-temperature-programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS), were employed to characterize the physicochemical properties of BaO-modified Pd-only catalyst. Catalytic activity for methanol, CO, C3H8 and NO conversions showed that BaO-modified catalyst prepared by impregnation method exhibited the best performance for methanol, C3H8 and NO removals, while the catalyst prepared by co-precipitation method was in favor of CO oxidation. Combined with the results of XRD, H2-TPR and XPS, it is concluded that the co-existence of PdO and Pd-O-Ce active species by impregnation played an important role in the methanol, C3H8 and NO removals, while the higher dispersion of palladium and improved reducibility were mostly favorable to the CO oxidation. The conversion of NO was co-effected by tow active species and the formation of Ba2AlLaO5 mixed oxide.

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Catalytic Dry Reforming and Cracking of Ethylene for Carbon Nanofilaments and Hydrogen Production Using a Catalyst Derived from a Mining Residue

Catalysts ◽

10.3390/catal9121069 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1069 ◽

Cited By ~ 1

Author(s):

Abir Azara ◽

El-Hadi Benyoussef ◽

Faroudja Mohellebi ◽

Mostafa Chamoumi ◽

François Gitzhofer ◽

...

Keyword(s):

Electron Microscopy ◽

Fixed Bed ◽

Dry Reforming ◽

Fixed Bed Reactor ◽

Molar Ratio ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Spent Catalysts ◽

Temperature Programmed

In this study, iron-rich mining residue (UGSO) was used as a support to prepare a new Ni-based catalyst via a solid-state reaction protocol. Ni-UGSO with different Ni weight percentages wt.% (5, 10, and 13) were tested for C2H4 dry reforming (DR) and catalytic cracking (CC) after activation with H2. The reactions were conducted in a differential fixed-bed reactor at 550–750 °C and standard atmospheric pressure, using 0.5 g of catalyst. Pure gases were fed at a molar ratio of C2H4/CO2 = 3 for the DR reaction and C2H4/Ar = 3 for the CC reaction. The flow rate is defined by a GHSV = 4800 mLSTP/h.gcat. The catalyst performance is evaluated by calculating the C2H4 conversion as well as carbon and H2 yields. All fresh, activated, and spent catalysts, as well as deposited carbon, were characterized by Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX), transmission electron microscopy (TEM), temperature programmed reduction (TPR), and thermogravimetric analysis (TGA). The results so far show that the highest carbon and H2 yields are obtained with Ni-UGSO 13% at 750 °C for the CC reaction and at 650 °C for the DR reaction. The deposited carbon was found to be filamentous and of various sizes (i.e., diameters and lengths). The analyses of the results show that iron is responsible for the growth of carbon nanofilaments (CNF) and nickel is responsible for the split of C–C bonds. In terms of conversion and yield efficiencies, the performance of the catalytic formulations tested is proven at least equivalent to other Ni-based catalyst performances described by the literature.

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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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The Regeneration Properties of Manganese Oxide Sorbent under SO2 Atmosphere

Materials Science Forum ◽

10.4028/www.scientific.net/msf.859.140 ◽

2016 ◽

Vol 859 ◽

pp. 140-145 ◽

Cited By ~ 1

Author(s):

Hui Qing Wang ◽

Shang Guan Ju ◽

Li Ping Liu ◽

Xiao Wei Zhao ◽

Jie Mi

Keyword(s):

Manganese Oxide ◽

Photoelectron Spectroscopy ◽

Elemental Sulfur ◽

Fixed Bed ◽

Fixed Bed Reactor ◽

X Ray Diffraction ◽

X Ray ◽

Maximum Value ◽

Regeneration Mechanism ◽

Effects Of Temperature

The effects of temperature and concentration of sulfur dioxide on regeneration behavior of manganese oxide sorbent were studied in a fixed-bed reactor. The sorbents were characterized by X-ray diffraction and X-ray photoelectron spectroscopy. Subsequently, the regeneration mechanism was inferred and the yield of export elemental sulfur was calculated. The study shows that, the major regeneration products are Mn3O4, MnSO4 and a small amount of elemental sulfur under SO2 atmosphere.The sulfate can be converted to Mn3O4and Mn2O3 at 800 °C under N2 atmosphere. The elemental sulfur productivity increases with the increase of temperature and concentration of sulfur dioxide.The regeneration conversion attains maximum value (68%) at 800 °C under the atmosphere of 1.68% SO2, and the productivity of elemental sulfur reaches to maximum value (29%) under the conditions.

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Biodiesel Production on Monometallic Pt, Pd, Ru, and Ag Catalysts Supported on Natural Zeolite

Materials ◽

10.3390/ma14010048 ◽

2020 ◽

Vol 14 (1) ◽

pp. 48

Author(s):

Pawel Mierczynski ◽

Magdalena Mosińska ◽

Lukasz Szkudlarek ◽

Karolina Chalupka ◽

Misa Tatsuzawa ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Natural Zeolite ◽

Noble Metals ◽

Methyl Esters ◽

Physicochemical Characteristics ◽

Biodiesel Production ◽

X Ray Diffraction ◽

X Ray ◽

Yield Values ◽

Temperature Programmed

Biodiesel production from rapeseed oil and methanol via transesterification reaction facilitated by various monometallic catalyst supported on natural zeolite (NZ) was investigated. The physicochemical characteristics of the synthesized catalysts were studied by X-ray diffraction (XRD), Brunauer–Emmett–Teller method (BET), temperature-programmed-reduction in hydrogen (H2-TPR), temperature-programmed-desorption of ammonia (NH3-TPD), Scanning Electron Microscope equipped with EDX detector (SEM-EDS), and X-ray photoelectron spectroscopy (XPS) methods. The highest activity and methyl ester yields were obtained for the Pt/NZ catalyst. This catalyst showed the highest triglycerides conversion of 98.9% and fatty acids methyl esters yields of 94.6%. The activity results also confirmed the high activity of the carrier material (NZ) itself in the investigated reaction. Support material exhibited 90.5% of TG conversion and the Fatty Acid Methyl Esters yield (FAME) of 67.2%. Introduction of noble metals improves the TG conversion and FAME yield values. Increasing of the metal loading from 0.5 to 2 wt.% improves the reactivity properties of the investigated catalysts.

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

Catalysts ◽

10.3390/catal11050553 ◽

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.

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Enhanced Photocatalytic Activity of Cu2O Cabbage/RGO Nanocomposites under Visible Light Irradiation

Polymers ◽

10.3390/polym13111712 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1712

Author(s):

Appusamy Muthukrishnaraj ◽

Salma Ahmed Al-Zahrani ◽

Ahmed Al Otaibi ◽

Semmedu Selvaraj Kalaivani ◽

Ayyar Manikandan ◽

...

Keyword(s):

Electron Microscopy ◽

Thermo Gravimetric Analysis ◽

Visible Region ◽

Catalytic Performance ◽

Precipitation Method ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Dye Pollutants ◽

Transmission Electron

Towards the utilization of Cu2O nanomaterial for the degradation of industrial dye pollutants such as methylene blue and methyl orange, the graphene-incorporated Cu2O nanocomposites (GCC) were developed via a precipitation method. Using Hummers method, the grapheme oxide (GO) was initially synthesized. The varying weight percentages (1–4 wt %) of GO was incorporated along with the precipitation of Cu2O catalyst. Various characterization techniques such as Fourier-transform infra-red (FT-IR), X-ray diffraction (XRD), UV–visible diffused reflectance (UV-DRS), Raman spectroscopy, thermo gravimetric analysis (TGA), energy-dispersive X-ray analysis (EDX), and electro chemical impedance (EIS) were followed for characterization. The cabbage-like morphology of the developed Cu2O and its composites were ascertained from field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HR-TEM). In addition, the growth mechanism was also proposed. The results infer that 2 wt % GO-incorporated Cu2O composites shows the highest value of degradation efficiency (97.9% and 96.1%) for MB and MO at 160 and 220 min, respectively. Further, its catalytic performance over visible region (red shift) was also enhanced to an appreciable extent, when compared with that of other samples.

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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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