Combined Magnesia, Ceria and Nickel catalyst supported over γ-Alumina Doped with Titania for Dry Reforming of Methane

This study investigated dry reforming of methane (DRM) over combined catalysts supported on γ-Al2O3 support doped with 3.0 wt. % TiO2. Physicochemical properties of all catalysts were determined by inductively coupled plasma/mass spectrometry (ICP-MS), nitrogen physisorption, X-ray diffraction, temperature programmed reduction/oxidation/desorption/pulse hydrogen chemisorption, thermogravimetric analysis, and scanning electron microscopy. Addition of CeO2 and MgO to Ni strengthened the interaction between the Ni and the support. The catalytic activity results indicate that the addition of CeO2 and MgO to Ni did not reduce carbon deposition, but improved the activity of the catalysts. Temperature programmed oxidation (TPO) revealed the formation of carbon that is mainly amorphous and small amount of graphite. The highest CH4 and CO2 conversion was found for the catalyst composed of 5.0 wt. % NiO-10.0 wt. % CeO2/3.0 wt. %TiO2-γ-Al2O3 (Ti-CAT-II), resulting in H2/CO mole ratio close to unity. The optimum reaction conditions in terms of reactant conversion and H2/CO mole ratio were achieved by varying space velocity and CO2/CH4 mole ratio.

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Combined Magnesia, Ceria and Nickel Catalyst Supported over γ-Alumina Doped with Titania for Dry Reforming of Methane

10.20944/preprints201812.0215.v1 ◽

2018 ◽

Author(s):

Ahmed Al-Fatesh ◽

Samsudeen Kasim ◽

Ahmed Ibrahim ◽

Anis Fakeeha ◽

Ahmed Abasaeed ◽

...

Keyword(s):

Inductively Coupled Plasma ◽

Space Velocity ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

X Ray Diffraction ◽

Inductively Coupled ◽

Al2o3 Support ◽

Plasma Mass Spectrometry ◽

Optimum Reaction ◽

Temperature Programmed

This study investigated dry reforming of methane with combined catalysts supported on γ-Al2O3 support doped with 3.0 wt. % TiO2. The physicochemical properties of all the catalysts were determined by inductively-coupled plasma/mass spectrometry metal analysis, nitrogen physisorption, X-ray diffraction, temperature programmed reduction/desorption, thermogravimetric analysis, and scanning electron microscopy. The addition of CeO2 and MgO to Ni strengthened the interaction between the Ni and the support. The catalytic activity results indicated that the CeO2 and MgO addition to Ni did not do much in retarding carbon deposition, but they improved the activity of the catalysts. Among the tested catalysts, it was found that the catalyst with the composition of 5.0 wt % NiO-10.0 wt % CeO2/3.0 wt %TiO2-γ-Al2O3 resulted in the highest CH4 and CO2 conversion with H2/CO mole ratio close to unity. The optimum reaction conditions in terms of reactant conversion and H2/CO mole ratio were achieved by varying space velocity and CO2/CH4 mole ratio.

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Dry Reforming of Methane Using Ce-modified Ni Supported on 8%PO4 + ZrO2 Catalysts

Catalysts ◽

10.3390/catal10020242 ◽

2020 ◽

Vol 10 (2) ◽

pp. 242

Author(s):

Ahmed A. Ibrahim ◽

Ahmed S. Al-Fatesh ◽

Nadavala Siva Kumar ◽

Ahmed E. Abasaeed ◽

Samsudeen O. Kasim ◽

...

Keyword(s):

Space Velocity ◽

Catalyst System ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Impregnation Method ◽

X Ray Diffraction ◽

Temperature Programmed Oxidation ◽

Active Metal ◽

Temperature Programmed ◽

The Stability

Dry reforming of methane (DRM) was studied in the light of Ni supported on 8%PO4 + ZrO2 catalysts. Cerium was used to modify the Ni active metal. Different percentage loadings of Ce (1%, 1.5%, 2%, 2.5%, 3%, and 5%) were tested. The wet incipient impregnation method was used for the preparation of all catalysts. The catalysts were activated at 700 °C for ½ h. The reactions were performed at 800 °C using a gas hourly space velocity of 28,000 mL (h·gcat)−1. X-ray diffraction (XRD), N2 physisorption, hydrogen temperature programmed reduction (H2-TPR), temperature programmed oxidation (TPO), temperature programmed desorption (TPD), and thermogravimetric analysis (TGA) were used for characterizing the catalysts. The TGA analysis depicted minor amounts of carbon deposition. The CO2-TPD results showed that Ce enhanced the basicity of the catalysts. The 3% Ce loading possessed the highest surface area, the largest pore volume, and the greatest pore diameter. All the promoted catalysts enhanced the conversions of CH4 and CO2. Among the promoted catalysts tested, the 10Ni + 3%Ce/8%PO4 + ZrO2 catalyst system operated at 1 bar and at 800 °C gave the highest conversions of CH4 (95%) and CO2 (96%). The stability profile of Cerium-modified catalysts (10%Ni/8%PO4 + ZrO2) depicted steady CH4 and CO2 conversions during the 7.5 h time on stream.

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Effects of the Mg addition on characteristics and catalytic activity of Ni/-Al2O3 in dry reforming of methane

Science and Technology Development Journal - Natural Sciences ◽

10.32508/stdjns.v1it5.538 ◽

2018 ◽

Vol 1 (T5) ◽

pp. 85-94

Author(s):

Loc Cam Luu ◽

Tri Nguyen ◽

Cuong Tien Hoang ◽

Tien Trong Nguyen ◽

Minh Hoang Phan ◽

...

Keyword(s):

Reaction Temperature ◽

Flow Reactor ◽

Coke Formation ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Co2 Reforming ◽

Temperature Programmed Oxidation ◽

Co2 Reforming Of Ch4 ◽

Temperature Programmed ◽

Α Al2o3

Effectively using CO2-containing natural gas is an urgent requirement in Vietnam. Therefore, producing hydrogen and syngas by dry reforming of methane (СН4+СО2 = 2Н2+2СО) has gained renewed interest in recent years. In this paper, Ni/α- Al2O3 and Ni-Mg/α-Al2O3 catalysts were prepared by impregnation. Physico-chemical characteristics of catalysts were investigated via nitrogen physisorption (BET), X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), and Temperature Programmed Reduction (TPR) methods. The activities of catalysts in CO2 reforming of CH4 were studied in a micro-flow reactor in the temperature range 550 –800oC, and content of CH4 and CO2 of 3 % mol. It was found that the conversion of CH4 and CO2 remarkably increased with the increase of reaction temperature from 550 to 700oC, but increased inconsiderably when the temperature reached more than 700oC. The selectivities of CO and H2 reached over 91 %. The modification of Ni/α- Al2O3 catalyst with Mg led to reduce the NiO particle size forme the new ZnO-MgO solid solution and increase the reductivity of catalyst. These improve the activity, selectivity and stability of catalyst. At the reaction temperature of 700oC, the conversions of CH4 and CO2 on Ni-Mg/α-Al2O3 reached 88.5 % and 72.3 %, respectively. The activities of catalysts were stable for 30 hours of reaction. Moreover, the role of Mg in the resistance to the coke formation on the catalyst surface was clarified via the results of temperature programmed oxidation (TPO) of spent catalysts after running the reaction for 30 hours at 700oC

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Novel Nickel- and Magnesium-Modified Cenospheres as Catalysts for Dry Reforming of Methane at Moderate Temperatures

Catalysts ◽

10.3390/catal9121066 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1066 ◽

Cited By ~ 2

Author(s):

Bogdan Samojeden ◽

Marta Kamienowska ◽

Armando Izquierdo Colorado ◽

Maria Elena Galvez ◽

Ilona Kolebuk ◽

...

Keyword(s):

Supported Catalysts ◽

Temperature Programmed Desorption ◽

Catalytic Performance ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Temperature Programmed Reduction ◽

Fly Ashes ◽

Coal Fly Ashes ◽

Temperature Programmed ◽

Mg Content

Cenospheres from coal fly ashes were used as support in the preparation of Ni–Mg catalysts for dry reforming of methane. These materials were characterized by means of XRD, H2-temperature-programmed reduction (H2-TPR), CO2-temperature-programmed desorption (CO2-TPD), and low-temperature nitrogen sorption techniques. The cenosphere-supported catalysts showed relatively high activity and good stability in the dry reforming of methane (DRM) at 700 °C. The catalytic performance of modified cenospheres was found to depend on both Ni and Mg content. The highest activity at 750 °C and 1 atm was observed for the catalyst containing 30 wt % Mg and 10, 20, and 30 wt % Ni, yielding to CO2 and CH4 conversions of around 95%.

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Surface Characterization of W/Ni/Al2O3 Catalysts

MRS Proceedings ◽

10.1557/proc-497-243 ◽

1997 ◽

Vol 497 ◽

Author(s):

M. H. Jordão ◽

J. M. Assaf ◽

P. A. P. Nascente

Keyword(s):

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Surface Characterization ◽

Nickel Content ◽

Stable Phase ◽

Preparation Methods ◽

X Ray ◽

Inductively Coupled ◽

Temperature Programmed ◽

Two Phases

ABSTRACTCatalysts containing tungsten and nickel oxides are important in hydrodesulfurization (HDS), hydrogénation (HY), and steam reforming of hydrocarbons. A series of W/Ni/Al2O3 catalysts was prepared by two different methods: (1) coprecipitation of nickel and aluminium hydroxicarbonate from their nitrates, followed by calcination and impregnation of tungsten; (2) precipitation of boehmite from aluminium nitrate, followed by impregnations of nickel, firstly, and tungsten. The nickel content was kept constant, while the amount of tungsten varied from 2.5 to 15.5 wt-%. The resulting oxides were characterized by inductively coupled plasma spectroscopy (ICP), atomic absorption spectroscopy (AAS), X-ray diffraction (XRD), temperature programmed reduction (TPR), and X-ray photoelectron spectroscopy (XPS). ICP and AAS were used to determine the W, Ni, and Al concentrations. XRD detected two phases: NiO and NiAl2O4 (no phase containing metallic tungsten was detected). Increasing the amount of W, the quantity of NiAl2O4 rose, the quantity of NiO decreased, and the particle size of NiO enlarged. The TPR profiles presented three peaks: one at about 1000 °C, associated to a very stable phase; for the samples prepared by coprecipitation, the other two peaks corresponded to “free NiO” and a nonstoichiometric aluminate. For the samples prepared by impregnation, those peaks corresponded to NiO and NiAl2O4. XPS identified Al2O3, NiAl2O4, and Al2(WO4)3 for both preparation methods. Increasing the amount of tungsten in the impregnated samples, NiWO4 was also observed.

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Synthesis and characterizations of TiN–SBA-15 mesoporous materials for CO2 dry reforming enhancement

Pure and Applied Chemistry ◽

10.1515/pac-2019-0806 ◽

2020 ◽

Vol 92 (4) ◽

pp. 545-556

Author(s):

Maslin Chotirach ◽

Supawan Tantayanon ◽

Duangamol Nuntasri Tungasmita ◽

Junliang Sun ◽

Sukkaneste Tungasmita

Keyword(s):

Photoelectron Spectroscopy ◽

Synthesis Method ◽

High Specific Surface Area ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Ni Catalyst ◽

X Ray ◽

Novel Approach ◽

Temperature Programmed ◽

Adsorption Desorption

AbstractA novel approach of titanium nitride (TiN) incorporated into SBA-15 framework was developed using one-step hydrothermal synthesis method. TiN contents up to ~18 wt% were directly dispersed in a synthetic gel under a typical strong acidic condition. The physico-chemical characteristics and the surface properties were investigated by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), N2 adsorption-desorption, field emission scanning electron microscope (FESEM) equipped with energy dispersive X-ray spectroscopy (EDS), wavelength dispersive X-ray fluorescence (WDXRF) and CO2-temperature programmed desorption (CO2-TPD). The results indicated that the highly ordered mesostructured was effectively maintained with high specific surface area of 532–685 m2g−1. The basicity of the modified SBA-15 increased with rising TiN loading. These modified materials were applied as a support of Ni catalyst in dry reforming of methane (DRM). Their catalytic behavior possessed superior conversions for both CO2 and CH4 with the highest H2/CO ratio (0.83) as well as 50 % lower carbon formation, compared to bare SBA-15 support.

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Ce- and Y-Modified Double-Layered Hydroxides as Catalysts for Dry Reforming of Methane: On the Effect of Yttrium Promotion

Catalysts ◽

10.3390/catal9010056 ◽

2019 ◽

Vol 9 (1) ◽

pp. 56 ◽

Cited By ~ 12

Author(s):

Katarzyna Świrk ◽

Magnus Rønning ◽

Monika Motak ◽

Patricia Beaunier ◽

Patrick Da Costa ◽

...

Keyword(s):

Textural Properties ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Side Reactions ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Temperature Programmed ◽

Nickel Species

Ce- and Y-promoted double-layered hydroxides were synthesized and tested in dry reforming of methane (CH4/CO2 = 1/1). The characterization of the catalysts was performed using X-ray fluorescence (XRF), X-ray diffraction (XRD), N2 sorption, temperature-programmed reduction in H2 (TPR-H2), temperature-programmed desorption of CO2 (TPD-CO2), H2 chemisorption, thermogravimetric analysis coupled by mass spectrometry (TGA/MS), Raman, and high-resolution transmission electron microscopy (HRTEM). The promotion with cerium influences textural properties, improves the Ni dispersion, decreases the number of total basic sites, and increases the reduction temperature of nickel species. After promotion with yttrium, the increase in basicity is not directly correlated with the increasing Y loading on the contrary of Ni dispersion. Dry reforming of methane (DRM) was performed as a function of temperature and in isothermal conditions at 700 °C for 5 h. For catalytic tests, a slight increase of the activity is observed for both Y and Ce doped catalysts. This improvement can of course be explained by Ni dispersion, which was found higher for both Y and Ce promoted catalysts. During DRM, the H2/CO ratio was found below unity, which can be explained by side reactions occurrence. These side reactions are linked with the increase of CO2 conversion and led to carbon deposition. By HRTEM, only multi-walled and helical-shaped carbon nanotubes were identified on Y and Ce promoted catalysts. Finally, from Raman spectroscopy, it was found that on Y and Ce promoted catalysts, the formed C is less graphitic as compared to only Ce-based catalyst.

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Generalized Methodology for Inserting Metal Heteroatoms into the Layered Zeolite Precursor RUB-36 by Interlayer Expansion

Crystals ◽

10.3390/cryst10060530 ◽

2020 ◽

Vol 10 (6) ◽

pp. 530 ◽

Cited By ~ 2

Author(s):

Chaoqun Bian ◽

Xiao Wang ◽

Lan Yu ◽

Fen Zhang ◽

Jie Zhang ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Catalytic Performance ◽

X Ray Diffraction ◽

Zeolite Sample ◽

X Ray ◽

Inductively Coupled ◽

Temperature Programmed ◽

First Time ◽

N2 Sorption

The incorporation of metal heteroatoms into zeolites is an effective modification strategy for enhancing their catalytic performance. Herein, for the first time we report a generalized methodology for inserting metal heteroatoms (such as Sn, Fe, Zn, and Co) into the layered zeolite precursor RUB-36 via interlayer expansion by using the corresponding metal acetylacetate salt. Through this generalized methodology, Sn-JHP-1, Fe-JHP-1, Zn-JHP-1 and Co-JHP-1 zeolites could be successfully prepared by the reaction of RUB-36 and corresponding metal acetylacetate salt at 180 °C for 24 h in the presence of HCl solution. As a typical example, Sn-JHP-1 and calcined Sn-JHP-1 (Sn-JHP-2) zeolite is well characterized by the X-ray diffraction (XRD), diffuse reflectance ultraviolet-visible (UV-Vis), inductively coupled plasma (ICP), N2 sorption, temperature-programmed-desorption of ammonia (NH3-TPD) and X-ray photoelectron spectroscopy (XPS) techniques, which confirm the expansion of adjacent interlayers and thus the incorporation of isolated Sn sites within the zeolite structure. Notably, the obtained Sn-JHP-2 zeolite sample shows enhanced catalytic performance in the conversion of glucose to levulinic acid (LA) reaction.

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