Thermodynamic and experimental study of combined dry and steam reforming of methane on Ru/ ZrO2-La2O3 catalyst at low temperature

Analysis of the effect of adding small amounts of steam to the methane dry reforming feed on activity and products distribution was performed from thermodynamic equilibrium calculations of the system based on the Gibbs free energy minimization method. This analysis is supported by new insights from the direct experimental investigation of the influence of co-feeding with H₂O over a Ru/ZrO₂-La₂O₃ catalyst. Activity measurements were carried out in a fixed-bed reactor but using the operating conditions applicable in a Pd membrane reactor, that is, at maximum reaction temperature below 550 °C. Experimental results were in good agreement with thermodynamics predictions. It was observed that the addition of H₂O into the dry reforming feed strongly affects activity and products distribution. The co-feeding of steam resulted in increasing methane conversion and hydrogen yield but decreasing carbon dioxide conversion and carbon monoxide yield. At a given temperature, syngas composition (H₂/CO ratio) can be tuned by changing the amount of H₂O co-fed. Interestingly the stability of the Ru/ZrO₂-La₂O₃ catalyst was improved by adding steam to the dry reforming reactant mixtures.     

Combined air partial oxidation and CO2 reforming of coal bed methane to synthesis gas over co-precipitated Ni-Mg-ZrO2 catalyst

The present study aims at exploring a concept which can convert coal-bed methane (containing methane, air and carbon dioxide) to synthesis gas. Without pre-separation and purification, the low-cost synthesis gas can be produced by coupling air partial oxidation and CO₂ reforming of coal bed methane. For this purpose, the co-precipitated Ni-Mg-ZrO₂ catalyst was prepared. It was found that the co-precipitated Ni-Mg-ZrO₂ catalyst exhibited the best activity and stability at 800 °C during the reaction. The conversions of CH₄ and CO₂ maintained at 94.8% and 82.1% respectively after 100 h of reaction. The effect of reaction temperature was investigated. The H₂/CO ratio in the product was mainly dependent on the feed gas composition. By changing O₂/CO₂ ratio of the feed gases, the H₂/CO ratio in the off-gas varied between 0.8 and 1.8. The experimental results showed that the high thermal stability and basic properties of the catalyst, and the strong metal-support interaction played important roles in improving the activity and stability of the catalyst. With the combined reactions and the Ni-Mg-ZrO₂ catalyst, the coal bed methane could be converted to synthesis gas, which can meet the need of the subsequent synthesis processes.     

Modifying perovskite-type oxide catalyst LaNiO3 with Ce for carbon dioxide reforming of methane

Perovskite-type oxide catalysts LaNiO₃ and La_1−xCe_xNiO₃ (x ≤ 0.5) were prepared by the Pechini method and used as catalysts for carbon dioxide reforming of methane to form synthesis gas (H₂ + CO). The gaseous reactants consisted of CO₂ and CH₄ in a molar ratio of 1:1. At a GHSV of 10,000 hr⁻¹, CH₄ conversion over LaNiO₃ catalyst increased from 66% at 600 °C to 94% at 800 °C, while CO₂ conversion increased from 51% to 92%. The achieved selectivities of CO and H₂ were 33% and 57%, respectively, at 600 °C. To prevent the deposition of carbon and the sintering nickel species, some of the Ni in perovskite-type oxide catalyst was substituted by Ce. Ce provided lattice oxygen vacancies, which activated C–H bonds, and increased the selectivity of H₂ to 61% at 600 °C. XRD analysis indicates that the catalyst exhibited a typical perovskite spinel structure and formed La₂O₂CO₃ phases after CO₂ reforming. The FE-SEM results reveal carbon whisker of the LaNiO₃ catalyst and the BET analysis indicates that the specific surface area increases after the reforming reaction. The H₂-TPR results confirm that Ce metals can store and provide oxygen.     

Promotional effect of alkaline earth over Ni-La2O3 catalyst for CO2 reforming of CH4: Role of surface oxygen species on H2 production and carbon suppression

Alkaline earth elements (Mg, Ca and Sr) on Ni-La₂O₃ catalyst have been investigated as promoters for syngas production from dry CO₂ reforming of methane (DRM). The catalysis results of DRM performance at 600 °C show that the Sr-doped Ni-La₂O₃ catalyst not only yields the highest CH₄ and CO₂ conversions (∼78% and ∼60%) and highest H₂ production (∼42% by vol.) but also has the lowest carbon deposition over the catalyst surface. The XPS, O₂-TPD, H₂-TPR and FTIR results show that the excellent performance over the Sr-doped Ni-La₂O₃ catalyst is attributed to the presence of a high amount of lattice oxygen surface species which promotes C-H activation in DRM reaction, resulting in high H₂ production. Moreover, these surface oxygen species on the Ni-SDL catalyst can adsorb CO₂ molecules to form bidentate carbonate species, which can then react with the surface carbon species formed during DRM, resulting in higher CO₂ conversion and lower carbon formation.     

Redox cycling of CuFe2O4 supported on ZrO2 and CeO2 for two-step methane reforming/water splitting

CuFe₂O₄ supported on ZrO₂ and CeO₂ for two-step methane reforming was evaluated to determine if it could enhance the reactivity, CO selectivity and thermal stability of CuFe₂O₄. Two-step methane reforming consists of a syngas production step and a water splitting step. CuFe₂O₄ supported on ZrO₂ and CeO₂ was prepared using an aerial oxidation method. Non-isothermal methane reduction was carried out on TGA to compare the reactivity of CuFe₂O₄/ZrO₂ and CuFe₂O₄/CeO₂. In addition, a syngas production step was performed at 900 °C and water splitting was conducted at 800 °C alternatively five times to compare the methane conversion, CO selectivity, cycle ability and hydrogen production by water splitting in a fixed bed reactor. If the 1st syngas production step results are excluded due to over-oxidation, CuFe₂O₄/ZrO₂ and CuFe₂O₄/CeO₂ showed approximately 74.0–82.8% and 60.3–87.5% methane conversion, respectively, and 44.0–47.8% and 65.2–81.5% CO selectivity, respectively. Using CeO₂ and ZrO₂ as supports effectively improved the reactivity and methane conversion compared to CuFe₂O₄. CuFe₂O₄/ZrO₂ showed high methane conversion due to the high phase stability and thermal stability of ZrO₂ but the selectivity was not improved. After 5 successive cycles, the CeFeO₃ phase was found on CuFe₂O₄/CeO₂. Furthermore, methane conversion, CO selectivity and the amounts of hydrogen production of CuFe₂O4/CeO₂ increased with increasing number of cycles. Additional test up to the 11th cycle on CuFe₂O₄/CeO₂ revealed that CeO₂ is a better support that ZnO₂ in terms of the reactivity and CO selectivity.     

Three-dimensionally ordered macroporous LaFeO3 perovskites for chemical-looping steam reforming of methane

Three-dimensionally ordered macroporous (3DOM) LaFeO₃ and nano-LaFeO₃ perovskite-type oxides were synthesized by impregnation of polystyrene (PS) templates and combustion method, respectively. The obtained LaFeO₃ perovskites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, and hydrogen-temperature programmed reduction (H₂-TPR). The performance of the perovskites as oxygen carriers in chemical looping steam methane reforming (CL-SMR) to produce syngas (H₂ + CO) and hydrogen were investigated. The synthesized 3DOM-LaFeO₃ was pure crystalline perovskite giving a surface area of 8.088 m²/g, higher than that of nano-LaFeO₃ particles (4.323 m²/g). In the methane reduction stage, methane was partially oxidized into syngas at a H₂/CO molar ratio close to 2:1 by the 3DOM-LaFeO₃ in the main stage of the reactions. In the steam oxidation stage, the reduced perovskites were oxidized by steam to generate hydrogen simultaneously. No significant decrease of the yields of syngas and hydrogen was observed during ten successive redox cycles, indicating that the 3DOM-LaFeO₃ perovskites have good repeatability. In comparison to nano-LaFeO₃, 3DOM-LaFeO₃ has more stable reactivity of methane oxidation and better resistance to carbon formation. In spite of a part of 3DOM structure were collapsed in the course of the cyclic reactions, the specific surface area of the 3DOM-LaFeO₃ was still higher than that of the nano one. The better reactivity of 3DOM-LaFeO₃ compared with that of nano-LaFeO₃ is partially attributed to the higher surface area.     

Nanocomposite Ni/ZrO2: Highly active and stable catalyst for H2 production via cyclic stepwise methane reforming reactions

This work investigates the catalytic performance of nanocomposite Ni/ZrO₂-AN catalyst consisting of comparably sized Ni (10–15 nm) and ZrO₂ (15–25 nm) particles for hydrogen production from the cyclic stepwise methane reforming reaction with either steam (H₂O) or CO₂ at 500–650 °C, in comparison with a conventional Ni/ZrO₂-CP catalyst featuring Ni particles supported by large and widely sized ZrO₂ particles (20–400 nm). Though both catalysts exhibited similar activity and stability during the reactions at 500 and 550 °C, they showed remarkably different catalytic stabilities at higher temperatures. The Ni/ZrO₂-CP catalyst featured a significant deactivation even during the methane decomposition step in the first cycle of the reactions at ≥600 °C, but the Ni/ZrO₂-AN catalyst showed a very stable activity during at least 17 consecutive cycles in the cyclic reaction with steam. Changes in the catalyst beds at varying stages of the reactions were characterized with TEM, XRD and TPO–DTG and were correlated with the amount and nature of the carbon deposits. The Ni particles in Ni/ZrO₂-AN became stabilized at the sizes of around 20 nm but those in Ni/ZrO₂-CP kept on growing in the methane decomposition steps of the cyclic reaction. The small and narrowly sized Ni particles in the nanocomposite Ni/ZrO₂-AN catalyst led to a selective formation of filamentous carbons whereas the larger Ni particles in the Ni/ZrO₂-CP catalyst a preferred formation of graphitic encapsulating carbons. The filamentous carbons were favorably volatilized in the steam treatment step but the CO₂ treatment selectively volatilized the encapsulating carbons. These results identify that the nature but not the amount of carbon deposits is the key to the stability of Ni/ZrO₂ catalyst and that the nanocomposite Ni/ZrO₂-AN would be a promising catalyst for hydrogen production via cyclic stepwise methane reforming reactions.     

Autothermal reforming of methane over nickel catalysts supported on nanocrystalline MgAl2O4 with high surface area

In this paper autothermal reforming of methane (ATR) was carried out over MgAl₂O₄ supported Ni catalysts with various Ni loadings. MgAl₂O₄ spinel with high specific surface area, as nanocrystalline carrier for nickel catalysts was synthesized by co-precipitation method with the addition of pluronic P123 triblock copolymer as surfactant. The prepared samples were characterized by XRD, BET, TEM, SEM, TPR and TPH techniques. The results demonstrated that methane conversion is significantly increased with increasing the Ni content and methane conversion of 15% Ni/MgAl₂O₄ was higher than that of other catalysts in all operation temperatures. Furthermore the influences of H₂O/CH₄, and O₂/CH₄ molar ratio in feed and GHSV on activity of 5% Ni/MgAl₂O₄ catalyst were investigated.     

Syngas production via dry reforming of methane over CeO2 modified Ni/Al2O3 catalysts

Syngas production via dry reforming of methane (DRM) was experimentally investigated using Ni-based catalyst. Ni/Al₂O₃ modification with CeO₂ addition and O₂ addition in the reactant were employed in this study to suppress carbon deposition and to enhance catalyst activity. It was found that DRM performance can be enhanced using CeO₂ modified Ni/Al₂O₃ catalyst due to CeAlO₃ formation. However, an optimum amount of CeO₂ loading exists to obtain the best DRM performance due to the decrease in specific surface area as the CeO₂ loading increases. Without O₂ addition, the reverse water-gas shift reaction plays an important role in DRM. It was found that CH₄ conversion and CO yield were enhanced while CO₂ conversion and H₂ yield are decreased as the CO₂ amount in feedstock increased in DRM. With O₂ addition in the fed reactant, it was found that the methane oxidation reaction plays an important role in DRM. CH₄ conversion can be enhanced by O₂ addition. However, decreases in CO₂ conversion and H₂ and CO yields occurred due to greater H₂O and CO₂ productions from the methane oxidation reaction. The thermogravimetric analysis (TGA) results showed that CeO₂ modified Ni/Al₂O₃ catalyst would have the lowest amount of carbon deposition when O₂ is introduced into the reaction.     

Combined catalytic partial oxidation and CO2 reforming of methane over ZrO2-modified Ni/SiO2 catalysts using fluidized-bed reactor

Nickel on zirconium-modified silica was prepared and tested as a catalyst for reforming methane with CO₂ and O₂ in a fluidized-bed reactor. A conversion of CH₄ near thermodynamic equilibrium and low H₂/CO ratio (1<H₂/CO<2) were obtained without catalyst deactivation during 10 h, in a most energy efficient and safe manner. A weight loading of 5 wt% zirconium was found to be the optimum. The catalysts were characterized using X-ray diffraction (XRD), H₂-temperature reaction (H₂-TPR), CO₂-temperature desorption (CO₂-TPD) and transmission election microscope (TEM) techniques. Ni sintering was a major reason for the deactivation of pure Ni/SiO₂ catalysts, while Ni dispersed highly on a zirconium-promoted Ni/SiO₂ catalyst. The different kinds of surface Ni species formed on ZrO₂-promoted catalysts might be responsible for its high activity and good resistance to Ni sintering.     

Properties of Ni/Y2O3 and its catalytic performance in methane conversion to syngas

Ni/Y₂O₃, with Y₂O₃ support prepared by the conventional precipitation method, was prepared by an impregnation method. The physicochemical properties of Y₂O₃ and Ni/Y₂O₃ were characterized by BET, CO₂-TPD, NH₃-TPD, TPR, XRF and TGA, and compared with those of γ-Al₂O₃ and Ni/γ-Al₂O_3, respectively. The catalytic performance of Ni/Y₂O₃ in the reaction of partial oxidation of methane (POM) to syngas was evaluated and compared with that of Ni/γ-Al₂O₃ catalyst, too. The results showed that, Y₂O₃ was a basic support with few acidic sites while γ-Al₂O₃ was an acidic support. NiO particles supported on Y₂O₃ were more easily to be reduced than those supported on γ-Al₂O₃. In the partial oxidation of methane, Ni/Y₂O₃ catalyst showed high catalytic activity and exhibited better catalytic stability than Ni/γ-Al₂O₃. After POM reaction at 700 °C for 550 h, methane conversion decreased little and only 2.2 wt% carbon was deposited on Ni/Y₂O₃ catalyst. Ni/Y₂O₃ was stable in POM even after a series of reaction temperature variations within the temperature range of 400 ∼ 800 °C.     

Carbon dioxide reforming of methane to synthesis gas over Ni/Si3N4 catalysts

Silicon nitride supported nickel catalyst prepared by impregnation using nickel nitrate solution was employed for the carbon dioxide reforming of methane. The catalyst was tested at 800 °C under atmospheric pressure. The influences of Ni loading and calcination temperature on the catalytic performance were investigated. It was found that the nickel loading and calcination temperature strongly influenced the catalytic performance. Over the 7 wt. % Ni/Si₃N₄ catalyst calcined at 400 °C, the conversions of CH₄ and CO₂ can achieve 95% and 91%, respectively. Appropriate interaction between the metal and the basic support makes the catalyst more resistant to sintering and coking, and thus an excellent stability.     

The effect of impregnation strategy on methane dry reforming activity of Ce promoted Pt/ZrO2

Dry reforming of methane has been studied over Pt/ZrO₂ catalysts promoted with Ce for different temperatures and feed compositions. The influence of the impregnation strategy and the cerium amount on the activity and stability of the catalysts were investigated. The results have shown that introduction of 1 wt.% Ce to the Pt/ZrO₂ catalyst via coimpregnation method led to the highest catalytic activity and stability. 1 wt.%Ce–1 wt.%Pt/ZrO₂ catalyst prepared by sequential impregnation displayed inferior CH₄ and CO₂ conversion performances with lowest H₂/CO production ratios. 1 wt.%Ce–1 wt.%Pt/ZrO₂ catalyst prepared by coimpregnation showed the highest activity even for the feed with high CH₄/CO₂ ratio. The reason for high activity was explained by the intensive interaction between Pt and Ce phases for coimpregnated sample, which had been verified by X-ray photoelectron spectroscopy and Energy Dispersive X-Ray analyses. Strong and extensive Pt–Ce surface interaction results in an increase in the number of Ce³⁺ sites and enhances the dispersion of Pt.     

Tri-reforming of methane over Ni@SiO2 catalyst

A nickel-silica core@shell catalyst was applied for a methane tri-reforming process in a fixed-bed reactor. To determine the optimal condition of the tri-reforming process for production of syngas appropriate for methanol synthesis the effect of reaction temperature (550–750 °C), CH₄:H₂O molar ratio (1:0–3.0) and CH₄:O₂ molar ratio (1:0–0.5) in the feedstock was investigated. CH₄ conversion rate and H₂/CO ratio in the produced syngas were influenced by the feedstock composition. Increasing the amount of steam above the proportion of CH₄:H₂O 1:0.5 reduced the H₂:CO molar ratio in produced syngas to ∼1.5. Increasing oxygen partial pressure improved methane conversion to 90% at 750 °C. At low ∼550 °C reaction temperature the tri-reforming process was not effective with low hydrogen production (H₂ yield ∼20%) and very low <5% CO₂ conversion. Increasing reaction temperature increased hydrogen yield to ∼85% at 750 °C. From all the tested reaction conditions the optimal for tri-reforming over the 11%Ni@SiO₂ catalyst was: feed composition with molar ratio CH₄:CO₂:H₂O:O₂:He 1:0.5:0.5:0.1:0.4 at T = 750 °C. The results were explained in the context of characterisation of the catalysts used. The obtained results showed that the tri-reforming process can be applied for production of syngas with composition suitable for methanol synthesis.     

Steam enhanced carbon dioxide reforming of methane in DBD plasma reactor

Considering the inevitable high energy input to implement the CO₂ reforming of methane under high-temperature operation using conventional catalysis method, the low temperature conversion of CO₂ and methane in the coaxial dielectric barrier discharge (DBD) plasma reactor was investigated in this work. Steam was introduced to enhance the CO₂ reforming of methane with synergetic catalysis effect by cold plasma and catalyst. The experimental results showed that a certain percent of steam could promote the conversion of both CH₄ and CO₂. Meanwhile, the carbon deposition was evidently reduced compared with the dry reforming of methane. With the increase of steam input, the steam reforming occurred predominantly. As a result, the hydrogen volume percentage in the product gases increased. In this way, the products with different H₂/CO ratio could be achieved by changing the mole ratio of CH₄/CO₂/H₂O at the reactor inlet. In particular, when the mole ratio of H₂O/CH₄ increased to almost 3 corresponding to the pure steam reforming process, the conversion of CH₄ reached almost 0.95 and the selectivity to H₂ was almost 0.99 at 773K.     

Hydrogen production by steam reforming of ethanol over an Ir/CeO2 catalyst: Reaction mechanism and stability of the catalyst

Steam reforming of ethanol over an Ir/CeO₂ catalyst has been studied with regard to the reaction mechanism and the stability of the catalyst. It was found that ethanol dehydrogenation to acetaldehyde was the primary reaction, and acetaldehyde was then decomposed to methane and CO and/or converted to acetone at low temperatures. Methane was further reformed to H₂ and CO, and acetone was directly converted into H₂ and CO₂. Addition of CO, CO₂, and CH₄ to the water/ethanol mixture proved that steam reforming of methane and the water gas shift were the major reactions at high temperatures. The Ir/CeO₂ catalyst displayed rather stable performance in the steam reforming of ethanol at 650 °C even with a stoichiometric feed composition of water/ethanol, and the effluent gas composition remained constant for 300 h on-stream. The CeO₂ in the catalyst prevented the highly dispersed Ir particles from sintering and facilitated coke gasification through strong Ir–CeO₂ interaction.     

Synthesis gas production in the combined CO2 reforming with partial oxidation of methane over Ce-promoted Ni/SiO2 catalysts

A series of nickel-based catalyst supported on silica (Ni/SiO₂) with different loading of Ce/Ni (molar ratio ranging from 0.17 to 0.84) were prepared using conventional co-impregnation method and were applied to synthesis gas production in the combination of CO₂ reforming with partial oxidation of methane. Among the cerium-containing catalysts, the cerium-rich ones exhibited the higher activity and stability than the cerium-low ones. The temperature-programmed reduction (TPR) and UV–vis diffuse reflectance spectroscopy (UV–vis DRS) analysis revealed that the addition of CeO₂ reduced the chemical interaction between Ni and support, resulting in an increase in reducibility and dispersion of Ni. Over NiCe-x/SiO₂ (x = 0.17, 0.50, 0.67, 0.84) catalysts, the reduction peak in TPR profiles shifted to the higher temperature with increasing Ce/Ni molar ratio, which was attributed to the smaller metallic nickel size of the reduced catalysts. The transmission electron microscopy (TEM) and X-ray diffraction (XRD) for the post-reaction catalysts confirmed that the promoter retained the metallic nickel species and prevented the metal particle growth at high reaction temperature. The NiCe-0.84/SiO₂ catalyst with small Ni particle size exhibited the stable activity with the constant H₂/CO molar ratio of 1.2 during 6-h reaction in the combination of CO₂ reforming with partial oxidation of methane at 850 °C and atmospheric pressure.     

Bio-oil steam reforming,partial oxidation or oxidative steam reforming coupled with bio-oil dry reforming to eliminate CO2 emission

Biomass is carbon-neutral and utilization of biomass as hydrogen resource shows no impact on atmospheric CO₂ level. Nevertheless, a significant amount of CO₂ is always produced in biomass gasification processes. If the CO₂ produced can further react with biomass, then the biomass gasification coupled with CO₂ reforming of biomass will result in a net decrease of CO₂ level in atmosphere and produce the chemical raw material, syngas. To achieve this concept, a “Y” type reactor is developed and applied in bio-oil steam reforming, partial oxidation, or oxidative steam reforming coupled with CO₂ reforming of bio-oil to eliminate the emission of CO₂. The experimental results show that the reaction systems can efficiently suppress the emission of CO₂ from various reforming processes. The different coupled reaction systems generate the syngas with different molar ratio of CO/H₂. In addition, coke deposition is encountered in the different reforming processes. Both catalysts and experimental parameters significantly affect the coke deposition. Ni/La₂O₃ catalyst shows much higher resistivity toward coke deposition than Ni/Al₂O₃ catalyst, while employing high reaction temperature is vital for elimination of coke deposition. Although the different coupled reaction systems show different characteristic in terms of product distribution and coke deposition, which all can serve as methods for storage of the carbon from fossil fuels or air.     

Autothermal reforming of methane for producing high-purity hydrogen in a Pd/Ag membrane reactor

Autothermal reforming of methane includes steam reforming and partial oxidizing methane. Theoretically, the required endothermic heat of steam reforming of methane could be provided by adding oxygen to partially oxidize the methane. Therefore, combining the steam reforming of methane with partial oxidation may help in achieving a heat balance that can obtain better heat efficacy. Membrane reactors offer the possibility of overcoming the equilibrium conversion through selectively removing one of the products from the reaction zone. For instance, only can hydrogen products permeate through a palladium membrane, which shifts the equilibrium toward conversions that are higher than the thermodynamic equilibrium. In this study, autothermal reforming of methane was carried out in a traditional reactor and a Pd/Ag membrane reactor, which were packed with an appropriate amount of commercial Ni/MgO/Al₂O₃ catalyst. A power analyzer was employed to measure the power consumption and to check the autothermicity. The average dense Pd/Ag membrane thickness is 24.3 μm, which was coated on a porous stainless steel tube via the electroless palladium/silver plating procedure. The experimental operating conditions had temperatures that were between 350 °C and 470 °C, pressures that were between 3 atm and 7 atm, and O₂/CH₄ = 0–0.5. The effects of the operating conditions on methane conversion, permeance of hydrogen, H₂/CO, selectivities of CO_x, amount of power supply, and the carbon deposition of the catalyst after the reaction is thoroughly discussed in this paper. The experimental results indicate that an optimum methane conversion of 95%, with a hydrogen production rate of 0.093 mol/m². S, can be obtained from the autothermal reforming of methane at H₂O/CH₄ = 1.3 and O₂/CH₄ near 0.4, at which the reaction does not consume power, and the catalysts are not subject to any carbon deposition.     

Ni-based catalysts for reforming of methane with CO2

Ni catalysts supported on different carriers like δ,θ-Al₂O₃, MgAl₂O₄, SiO₂–Al₂O₃ and ZrO₂–Al₂O₃ were prepared. The solids were characterized by chemical analysis, N₂ adsorption–desorption isotherms, X-ray powder diffraction, UV–vis diffuse reflectance spectroscopy, temperature-programmed reduction, high-resolution transmission electron microscopy and temperature-programmed oxidation. The catalytic properties of the samples were evaluated in the reaction of reforming of methane with CO₂ at 923 K. It was shown that this kind of support greatly affects the structure and catalytic performance of the catalysts. Ni catalyst supported on MgAl₂O₄ showed the highest activity and stability due to the presence of small well dispersed Ni particles with size of 5.1 nm. It was shown that the lowest activity of Ni catalyst supported on SiO₂–Al₂O₃ oxide was caused by the agglomeration of nickel particles and formation of filamentous carbon under reaction conditions detected by the high resolution transmission electron microscopy.