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

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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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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Characterization of LaRhO3 perovskites for dry (CO2) reforming of methane (DRM)

Chemical Papers ◽

10.2478/s11696-014-0566-2 ◽

2014 ◽

Vol 68 (9) ◽

Cited By ~ 8

Author(s):

Ted Johansson ◽

Devendra Pakhare ◽

Daniel Haynes ◽

Victor Abdelsayed ◽

Dushyant Shekhawat ◽

...

Keyword(s):

Dry Reforming ◽

Broad Peak ◽

Dry Reforming Of Methane ◽

Single Type ◽

Side Reactions ◽

Boudouard Reaction ◽

Co2 Reforming ◽

Xrd Pattern ◽

Temperature Programmed

AbstractThis work reports on the characterization of LaRhO3 perovskite as a catalyst for dry reforming of methane. The catalyst was studied using CH4-temperature programmed reduction (TPR), H2-TPR, and temperature programmed surface reaction (TPSR), and the changes in the crystal structure of the catalyst due to these treatments were studied by X-ray diffraction (XRD). XRD pattern of the freshly calcined perovskites showed the formation of highly crystalline LaRhO3 and La2O3 phases. H2-TPR of the fresh calcined catalyst showed a shoulder at 342°C and a broad peak at 448°C, suggesting that the reduction of Rh in perovskite occurs in multiple steps. XRD pattern of the reduced catalyst suggests complete reduction of the LaRhO3 phase and the formation of metallic Rh and minor amounts of La(OH)3. The CH4-TPR data show qualitatively similar results as H2-TPR, with a shoulder and a broad peak in the same temperature range. Following the H2-TPR up to 950°C, the same batch of catalyst was oxidized by flowing 5 vol. % O2/He up to 500°C and a second H2-TPR (also up to 950°C) was conducted. This second H2-TPR differed significantly from that of the fresh calcined catalyst. The single sharp peak at 163°C in the second H2-TPR suggests a significant change in the catalyst, probably causedby the transformation of about 90 % of the perovskite into Rh/La2O3. This was confirmed by the XRD studies of the catalyst reduced after the oxidation at 500°C. TPSR of the dry reforming reaction on the fresh calcined catalyst showed CO and H2 formation starting at 400°C, with complete consumption of the reactants at 650°C. The uneven consumption of reactants between 400°C and 650°C suggests that reactions other than DRM occur, including reverse water gas shift (RWGS) and the Boudouard reaction (BR), probably as a result of in-situ changes in the catalyst, consistent with the H2-TPR results. TPSR, after a H2-TPR up to 950°C, showed that the dry reforming reaction did not light off until 570°C, which is much higher temperature than the one observed using fresh calcined catalyst. This shows that the uniform sites produced during the 950°C H2-TPR are catalytically less active than those of the fresh calcined catalyst, and that no significant side reactions such as RWGS or the Boudouard reaction occur. This suggests that reduction leads to the formation of a single type of sites which do not catalyze simultaneous side reactions.

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CO2 Reforming of Methane over LaNiO3 Perovskite Supported Catalysts: Influence of Silica Support

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.14.3.3472.568-578 ◽

2019 ◽

Vol 14 (3) ◽

pp. 568 ◽

Cited By ~ 2

Author(s):

Djamila Sellam ◽

Kahina Ikkour ◽

Sadia Dekkar ◽

Hassiba Messaoudi ◽

Taous Belaid ◽

...

Keyword(s):

Supported Catalysts ◽

Catalyst Support ◽

Combustion Method ◽

Catalytic Performance ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

High Catalytic Activity ◽

Co2 Reforming ◽

Auto Combustion ◽

Temperature Programmed

The study presents the dry reforming of methane using natural Kaolin silica as catalyst support. The silica-supported LaNiO3 perovskite catalysts (20LaNiO3/SiO2 and 40LaNiO3/SiO2) and bulk LaNiO3 catalyst were synthesized by auto-combustion method. The resulting catalysts were characterized by X-ray diffraction (XRD), N2 adsorption - desorption isotherm measurement, scanning electron microscopy (SEM) and temperature-programmed reduction (TPR). After reduction at 700 °C, they were used as catalysts for the reaction of dry reforming of methane into synthesis gas at atmospheric pressure at 800 °C. The reduced 40LaNiO3/SiO2 exhibited high catalytic activity. This result was attributed to the small Ni metallic particles obtained from the reduced perovskite highly dispersed on the support and the good reducibility. The increase of reduction temperature at 800 °C resulted in a further enhancement of the catalytic performance of 40LaNiO3/SiO2 catalyst. Copyright © 2019 BCREC Group. All rights reserved

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Enhancement of CO2 Reforming of CH4 Reaction Using Ni,Pd,Pt/Mg1−xCex4+O and Ni/Mg1−xCex4+O Catalysts

Catalysts ◽

10.3390/catal10111240 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1240

Author(s):

Faris A. J. Al-Doghachi ◽

Ali F. A. Jassim ◽

Yun Hin Taufiq-Yap

Keyword(s):

Activity Level ◽

Catalyst Characterization ◽

Co2 Reforming ◽

Temperature Programmed Oxidation ◽

Co2 Reforming Of Ch4 ◽

Temperature Ranges ◽

Spent Catalysts ◽

Elevated Activity ◽

Temperature Programmed ◽

Co Precipitation

Catalysts Ni/Mg1−xCex4+O and Ni,Pd,Pt/Mg1−xCex4+O were developed using the co-precipitation–impregnation methods. Catalyst characterization took place using XRD, H2-TPR, XRF, XPS, Brunauer–Emmett–Teller (BET), TGA TEM, and FE-SEM. Testing the catalysts for the dry reforming of CH4 took place at temperatures of 700–900 °C. Findings from this study revealed a higher CH4 and CO2 conversion using the tri-metallic Ni,Pd,Pt/Mg1−xCex4+O catalyst in comparison with Ni monometallic systems in the whole temperature ranges. The catalyst Ni,Pd,Pt/Mg0.85Ce4+0.15O also reported an elevated activity level (CH4; 78%, and CO2; 90%) and an outstanding stability. Carbon deposition on spent catalysts was analyzed using TEM and Temperature programmed oxidation-mass spectroscopy (TPO-MS) following 200 h under an oxygen stream. The TEM and TPO-MS analysis results indicated a better anti-coking activity of the reduced catalyst along with a minimal concentration of platinum and palladium metals.

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Dry Reforming of Methane over NiLa-Based Catalysts: Influence of Synthesis Method and Ba Addition on Catalytic Properties and Stability

Catalysts ◽

10.3390/catal9040313 ◽

2019 ◽

Vol 9 (4) ◽

pp. 313 ◽

Cited By ~ 2

Author(s):

Ruan Gomes ◽

Denilson Costa ◽

Roberto Junior ◽

Milena Santos ◽

Cristiane Rodella ◽

...

Keyword(s):

Catalyst Deactivation ◽

Synthesis Method ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Co2 Reforming ◽

Catalyst Structure ◽

Wet Impregnation ◽

Co2 Reforming Of Ch4 ◽

Key Factor

CO2 reforming of CH4 to produce CO and H2 is a traditional challenge in catalysis. This area is still very active because of the potentials offered by the combined utilization of two green-house gases. The development of active, stable, and economical catalysts remains a key factor for the exploitation of natural gas (NG) with captured CO2 and biogas to produce chemicals or fuels via syngas. The major issue associated with the dry reforming process is catalyst deactivation by carbon deposition. The development of suitable catalyst formulations is one strategy for the mitigation of coking which becomes especially demanding when noble metal-free catalysts are targeted. In this work NiLa-based catalyst obtained from perovskite precursors La1−xBaxNiO3 (x = 0.0; 0.05; 0.1 and 0.2) and NiO/La2O3 were synthesized, characterized by in situ and operando XRD and tested in the dry reforming of methane. The characterization results showed that the addition of barium promoted BaCO3 segregation and changes in the catalyst structure. This partly affected the activity; however, the incorporation of Ba improved the catalyst resistance to deactivation process. The Ba-containing and Ba-free NiLa-based catalysts performed significantly better than NiO/La2O3 catalysts obtained by wet impregnation.

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CO2 reforming of CH4 over M(Ca, Ba, Sr)xLa1-xNiO3 perovskites used as coke resistant catalyst precursor

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq190620040t ◽

2020 ◽

pp. 40-40

Author(s):

Ana Carolina Trevisani Souza ◽

Marcelo da Silva Batista

Keyword(s):

Catalytic Performance ◽

Partial Substitution ◽

High Catalytic Activity ◽

Catalyst Precursor ◽

Co2 Reforming ◽

Temperature Programmed Oxidation ◽

Co2 Reforming Of Ch4 ◽

Co2 Reforming Of Methane ◽

Temperature Programmed ◽

Carbon Dioxide Co2

Methane (CH4) and carbon dioxide (CO2) are greenhouse gases that have been converted into synthesis gas for the production of oxygenated chemicals and hydrocarbons. In this paper, M(Ca, Ba, Sr)xLa1-xNiO3 (x=0.0, 0.3 and 0.5) doped perovskites were successfully synthesized as catalyst precursors aiming at high catalytic activity and stability in the CO2 reforming of methane. These perovskites were characterized by X-ray diffraction (XRD), temperature programmed reduction by H2 (H2-TPR) and O2-temperature programmed oxidation (TPO). Its activity and carbon suppression were investigated in the CO2 reforming of methane. Results showed formation of perovskite structure, but La2NiO4 spinel and NiO were also detected in doped perovskites. The Ca, Ba and Sr partial substitution has evident influence on the reduction behavior of perovskites. All the doped perovskites used as catalyst precursors had better catalytic performance than LaNiO3. However, increasing the doping content decreased activity. Among doped perovskites, Ca0.3La0.7NiO3 showed better catalytic performance for the methane reforming reaction.

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

Catalysts ◽

10.3390/catal9020188 ◽

2019 ◽

Vol 9 (2) ◽

pp. 188 ◽

Cited By ~ 5

Author(s):

Ahmed Sadeq Al-Fatesh ◽

Samsudeen Olajide Kasim ◽

Ahmed Aidid Ibrahim ◽

Anis Hamza Fakeeha ◽

Ahmed Elhag Abasaeed ◽

...

Keyword(s):

Inductively Coupled Plasma ◽

Space Velocity ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Hydrogen Chemisorption ◽

Temperature Programmed Oxidation ◽

Inductively Coupled ◽

Al2o3 Support ◽

Optimum Reaction ◽

Temperature Programmed

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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Ni-Silica-based Catalysts for CH4 Reforming by CO2 with Enhanced Stability: Recent Designs and the Impacts of Ni Confinement, Promoters, and Core-Shell Structures

10.21926/jept.2101007 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Oscar Daoura ◽

◽

Maya Boutros ◽

Franck Launay ◽

Keyword(s):

Heterogeneous Catalysts ◽

Catalyst Deactivation ◽

High Surface ◽

High Surface Area ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Future Research ◽

Co2 Reforming ◽

Co2 Reforming Of Ch4 ◽

Oxide Support

CO2 reforming of CH4, also referred to as the Dry Reforming of Methane (DRM), is considered an excellent method to produce H2 and CO (syngas), which are known to be used for the production of higher alkanes and oxygenates. Despite nickel’s moderate toxicity, Ni-based heterogeneous catalysts are considered excellent candidates for use in DRM due to their reasonable performances and economic advantages. However, these materials also present severe drawbacks, such as sintering of the active phase and coke (carbon) deposition, which may, in certain cases, lead to severe catalyst deactivation. Several synthesis strategies, mostly based on the stabilization of nickel through oxide support, have been developed to overcome these issues. Silica-based materials are investigated widely due to their availability, high surface area, and the confinement capacity conferred by their controlled porosity. The present review summarizes the progress in the design of Ni/silica-based catalysts for the dry reforming of methane between the years 2015 and 2018. The different strategies implemented are discussed to assist future research works in designing the anti-coking and anti-sintering nickel-silica-based catalysts.

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Hydrogen Yield from CO2 Reforming of Methane: Impact of La2O3 Doping on Supported Ni Catalysts

Energies ◽

10.3390/en14092412 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2412

Author(s):

Ahmed Abasaeed ◽

Samsudeen Kasim ◽

Wasim Khan ◽

Mahmud Sofiu ◽

Ahmed Ibrahim ◽

...

Keyword(s):

Coke Formation ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Hydrogen Yield ◽

Co2 Reforming ◽

Base Catalysts ◽

Surface Areas ◽

Oxide Support ◽

Surface Basicity

Development of a transition metal based catalyst aiming at concomitant high activity and stability attributed to distinguished catalytic characteristics is considered as the bottleneck for dry reforming of methane (DRM). This work highlights the role of modifying zirconia (ZrO2) and alumina (Al2O3) supported nickel based catalysts using lanthanum oxide (La2O3) varying from 0 to 20 wt% during dry reforming of methane. The mesoporous catalysts with improved BET surface areas, improved dispersion, relatively lower reduction temperatures and enhanced surface basicity are identified after La2O3 doping. These factors have influenced the catalytic activity and higher hydrogen yields are found for La2O3 modified catalysts as compared to base catalysts (5 wt% Ni-ZrO2 and 5 wt% Ni-Al2O3). Post-reaction characterizations such as TGA have showed less coke formation over La2O3 modified samples. Raman spectra indicates decreased graphitization for La2O3 catalysts. The 5Ni-10La2O3-ZrO2 catalyst produced 80% hydrogen yields, 25% more than that of 5Ni-ZrO2. 5Ni-15La2O3-Al2O3 gave 84% hydrogen yields, 8% higher than that of 5Ni-Al2O3. Higher CO2 activity improved the surface carbon oxidation rate. From the study, the extent of La2O3 loading is dependent on the type of oxide support.

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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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