Статті в журналах: "Methane Reforming Catalysts"

1

Manan, Wan Nabilah, Wan Nor Roslam Wan Isahak, and Zahira Yaakob. "CeO2-Based Heterogeneous Catalysts in Dry Reforming Methane and Steam Reforming Methane: A Short Review." Catalysts 12, no. 5 (April 19, 2022): 452. http://dx.doi.org/10.3390/catal12050452.

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Transitioning to lower carbon energy and environment sustainability requires a reduction in greenhouse gases such as carbon dioxide (CO2) and methane (CH4) that contribute to global warming. One of the most actively studied rare earth metal catalysts is cerium oxide (CeO2) which produces remarkable improvements in catalysts in dry reforming methane. This paper reviews the management of CO2 emissions and the recent advent and trends in bimetallic catalyst development utilizing CeO2 in dry reforming methane (DRM) and steam reforming methane (SRM) from 2015 to 2021 as a way to reduce greenhouse gas emissions. This paper focus on the identification of key trends in catalyst preparation using CeO2 and the effectiveness of the catalysts formulated.

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2

Jiang, Hong Tao, Hui Quan Li, and Hao Fan. "Tri-Reforming of Methane over Pt Modified Ni/MgO Catalysts under Atmospheric Pressure – Thermal Distribution in the Catalyst Bed." Applied Mechanics and Materials 252 (December 2012): 255–58. http://dx.doi.org/10.4028/www.scientific.net/amm.252.255.

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Thermal distribution in catalyst bed was investigated for the fixed-bed tri-reforming of methane over Pt modified Ni/MgO catalysts under atmospheric pressure, 850 °C, and space velocity of 2000−20000 h−1. The effects of the W/F on the thermal distribution of different catalysts were examined. The results indicated that for Pt modified Ni/MgO catalysts, the temperature profile depended on catalysts preparation method. According to the thermal distribution, for Pt modified Ni/MgO catalysts prepared by sequence method, the catalyst bed can be divided into tow zones: auto-thermo reforming zone and oxygen absent zone. Methane reforming proceeds in both zones together.

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3

Meloni, Eugenio, Marco Martino, and Vincenzo Palma. "A Short Review on Ni Based Catalysts and Related Engineering Issues for Methane Steam Reforming." Catalysts 10, no. 3 (March 22, 2020): 352. http://dx.doi.org/10.3390/catal10030352.

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Hydrogen is an important raw material in chemical industries, and the steam reforming of light hydrocarbons (such as methane) is the most used process for its production. In this process, the use of a catalyst is mandatory and, if compared to precious metal-based catalysts, Ni-based catalysts assure an acceptable high activity and a lower cost. The aim of a distributed hydrogen production, for example, through an on-site type hydrogen station, is only reachable if a novel reforming system is developed, with some unique properties that are not present in the large-scale reforming system. These properties include, among the others, (i) daily startup and shutdown (DSS) operation ability, (ii) rapid response to load fluctuation, (iii) compactness of device, and (iv) excellent thermal exchange. In this sense, the catalyst has an important role. There is vast amount of information in the literature regarding the performance of catalysts in methane steam reforming. In this short review, an overview on the most recent advances in Ni based catalysts for methane steam reforming is given, also regarding the use of innovative structured catalysts.

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4

Tungatarova, Svetlana, Galina Xanthopoulou, George Vekinis, Konstantinos Karanasios, Tolkyn Baizhumanova, Manapkhan Zhumabek, and Marzhan Sadenova. "Ni-Al Self-Propagating High-Temperature Synthesis Catalysts in Dry Reforming of Methane to Hydrogen-Enriched Fuel Mixtures." Catalysts 12, no. 10 (October 18, 2022): 1270. http://dx.doi.org/10.3390/catal12101270.

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The worldwide increase in demand for environmentally friendly energy has led to the intensification of work on the synthesis of H2-containing fuel. The dry reforming of methane has become one of the most important avenues of research since the consumption of two greenhouse gases reduces the rate of global warming. A study of NiAl composite materials as catalysts for methane reforming has been carried out. Self-propagating high-temperature synthesis (SHS) has been used to produce NiAl catalysts. Comparative studies were carried out regarding the dry reforming and partial oxidation of methane, as well as catalysts prepared using the impregnation (IM) and SHS methods. A catalyst with 29% Ni and 51% Al after SHS contains the phases of NiAl and NiAl2O4, which are active phases in the dry reforming of methane. The optimal crystal lattice parameter (for the maximum possible conversion of CO2 and CH4) is 3.48–3.485 Å for Al2O3, which plays the role of a catalyst carrier, and 1.42 Å, for NiAl2O4, which plays the role of a catalyst. The aim of the work is to develop a new and efficient catalyst for the dry reforming of methane into a synthesis gas, which will further promote the organization of a new era of environmentally friendly energy-saving production methods.

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5

Yu, Xiaopeng, Fubao Zhang, and Wei Chu. "Effect of a second metal (Co, Cu, Mn or Zr) on nickel catalysts derived from hydrotalcites for the carbon dioxide reforming of methane." RSC Advances 6, no. 74 (2016): 70537–46. http://dx.doi.org/10.1039/c6ra12335j.

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6

Cho, Yohei, Akira Yamaguchi, and Masahiro Miyauchi. "Photocatalytic Methane Reforming: Recent Advances." Catalysts 11, no. 1 (December 25, 2020): 18. http://dx.doi.org/10.3390/catal11010018.

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Methane reforming is an important potential technology for solving both environmental and energy problems. This technology is important because methane is counted as a greenhouse gas, but on the other hand, it can be reformed into industrially valuable compounds. More research has focused on photocatalytic methane reforming, which has a higher activity than thermal catalysts under dark conditions. The reaction selectivity toward specific products in photocatalytic methane reforming is sometimes different from thermal catalyst systems. Herein, we discuss recent advances in photocatalytic methane reforming to provide various strategies for reforming.

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7

Osaki, Toshihiko, and Toshiaki Mori. "The Catalysis of NiO-Al₂O₃ Aerogels for the Methane Reforming by Carbon Dioxide." Advances in Science and Technology 45 (October 2006): 2137–42. http://dx.doi.org/10.4028/www.scientific.net/ast.45.2137.

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The aerogels of nickel-alumina system have been synthesized from aluminum triisoprppoxide and nickel glycoxide by sol-gel and subsequent supercritical drying, and the catalysis of NiO-Al2O3 aerogels for the methane reforming by carbon dioxide have been examined. The aerogel catalysts showed higher activity for the reforming than the impregnation catalysts prepared by a conventional impregnation method, on the other hand, the carbon deposition was much less significant on the aerogel catalysts than on the impregnation catalysts. By TEM and XRD observations, it was found for aerogel catalysts that fine nickel particles were formed throughout the alumina aerogel support with high dispersion. This resulted in not only higher catalytic reforming activity but also much less coking activity. The suppression of catalyst deactivation during the reforming was ascribed to the retardation of both carbon deposition and sintering of nickel particles on alumina aerogel support.

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8

Sivasangar, S., and Yun Hin Taufiq-Yap. "The Effect of CeO₂ and Fe₂O₃ Dopants on Ni/ Alumina Based Catalyst for Dry Reforming of Methane to Hydrogen." Advanced Materials Research 364 (October 2011): 519–23. http://dx.doi.org/10.4028/www.scientific.net/amr.364.519.

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Methane reforming is the most feasible techniques to produce hydrogen for commercial usage. Hence, dry reforming is the environment friendly method that uses green house gases such as CO2and methane to produce fuel gas. Catalysts play a vital role in methane conversion by enhancing the reforming process. In this study Ni/γ-Al2O3was selected as based catalyst and CeO2and Fe2O3dopants were added to investigate their effect on catalytic activity in dry reforming. The catalysts synthesized through wet impregnation method and characterized by using XRD, TEM and SEM-EDX. The catalytic tests were carried out using temperature programmed reaction (TPRn) and the products were detected by using an online mass spectrometer. The results revealed that these dopants significantly affect the catalytic activity and selectivity of the catalyst during reaction. Hence, Fe2O3doped catalyst shows higher hydrogen production with stable catalytic activity.

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9

Garbarino, Gabriella, Federico Pugliese, Tullio Cavattoni, Guido Busca, and Paola Costamagna. "A Study on CO2 Methanation and Steam Methane Reforming over Commercial Ni/Calcium Aluminate Catalysts." Energies 13, no. 11 (June 1, 2020): 2792. http://dx.doi.org/10.3390/en13112792.

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Three Ni-based natural gas steam reforming catalysts, i.e., commercial JM25-4Q and JM57-4Q, and a laboratory-made catalyst (26% Ni on a 5% SiO2–95% Al2O3), are tested in a laboratory reactor, under carbon dioxide methanation and methane steam reforming operating conditions. The laboratory catalyst is more active in both CO2 methanation (equilibrium is reached at 623 K with 100% selectivity) and methane steam reforming (92% hydrogen yield at 890 K) than the two commercial catalysts, likely due to its higher nickel loading. In any case, commercial steam reforming catalysts also show interesting activity in CO2 methanation, reduced by K-doping. The interpretation of the experimental results is supported by a one-dimensional (1D) pseudo-homogeneous packed-bed reactor model, embedding the Xu and Froment local kinetics, with appropriate kinetic parameters for each catalyst. In particular, the H2O adsorption coefficient adopted for the commercial catalysts is about two orders of magnitude higher than for the laboratory-made catalyst, and this is in line with the expectations, considering that the commercial catalysts have Ca and K added, which may promote water adsorption.

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10

O'Malley, Alexander J., Stewart F. Parker, and C. Richard A. Catlow. "Neutron spectroscopy as a tool in catalytic science." Chemical Communications 53, no. 90 (2017): 12164–76. http://dx.doi.org/10.1039/c7cc05982e.

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The unique power of neutron spectroscopy to probe molecular behaviour in catalytic systems is illustrated. Vibrational spectroscopy and quasielastic scattering techniques are introduced, along with their use in probing methanol-to-hydrocarbons and methane reforming catalysis, and also hydrocarbon behaviour in microporous catalysts.

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11

Gomes, Ruan, Denilson Costa, Roberto Junior, Milena Santos, Cristiane Rodella, Roger Fréty, Alessandra Beretta, and Soraia Brandão. "Dry Reforming of Methane over NiLa-Based Catalysts: Influence of Synthesis Method and Ba Addition on Catalytic Properties and Stability." Catalysts 9, no. 4 (March 30, 2019): 313. http://dx.doi.org/10.3390/catal9040313.

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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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12

Dedov, A. G., A. S. Loktev, V. A. Arkhipova, M. A. Bykov, A. A. Sadovnikov, K. A. Cherednichenko, and G. A. Shandryuk. "A New Approach to the Preparation of Stable Oxide-Composite Cobalt–Samarium Catalysts for the Production of Hydrogen by Dry Reforming of Methane." Processes 11, no. 8 (July 31, 2023): 2296. http://dx.doi.org/10.3390/pr11082296.

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A new approach to preparing a series of Co/Sm2O3 catalysts for hydrogen production by the dry reforming of methane has been developed. The catalyst precursors were synthesized with a simple method, including the evaporation of aqueous solutions of cobalt and samarium nitrates, followed by a short-term calcination of the resulting material. The as-prepared and spent catalysts were characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, temperature-programmed reduction, and thermogravimetric analysis. The content of cobalt in the synthesized materials affects their phase composition and carbonization resistance in the dry reforming of the methane reaction. It has been shown that preheating in N2 atmosphere produces catalysts that provide a stable yield of hydrogen and CO of 94–98% for at least 50 h at 900 °C. These yields are among the highest currently available for the dry reforming of methane catalysts made from Co-Sm complex oxides. It has been established that the decrease in the amount of cobalt in the catalyst and its preheating to an operating temperature of 900 °C in a nitrogen flow help to prevent the carbonization of the catalyst and the sintering of metal particles.

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13

Itkulova, Sholpan S. "Carbon Dioxide Reforming of Methane over Zeolite-containing Catalysts." Eurasian Chemico-Technological Journal 11, no. 3 (April 4, 2016): 231. http://dx.doi.org/10.18321/ectj285.

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Reforming of methane by carbon dioxide (dry reforming of methane) has been studied over the series of the 5% Со-М/Al2O3+ zeolite catalysts. The effect of zeolite (type, module, and amount) added to support composition on performance of the Со-М/Al2O3 catalyst in dry reforming has been examined. It has been shown that syngas is a main product of dry reforming over the zeolite-containing catalysts. Also, some amount (up to 3%) of acetic acid is produced. The yield of syngas and acetic acid depends on nature and amount of zeolite and process conditions.

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14

Ravil Mustafin and Igor Karpilov. "Effect of the Catalyst Shapes and the Packed Bed Structure on the Efficiency of Steam Methane Reforming." Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 104, no. 1 (April 3, 2023): 124–40. http://dx.doi.org/10.37934/arfmts.104.1.124140.

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One of the promising technologies for on-board hydrogen production is methane steam reforming in reactor with packed bed. The study of the effect of various catalytic packing arrangements on the steam methane reforming process is of considerable interest. The present article analyses the influence of catalyst shapes and packing arrangement on steam methane reforming reactions efficiency. The reformer tube contains several packings with a changing relative position; additionally, two forms of catalysts, a ball and a cylinder, are also used. The pressure drop depending on the packing location, methane conversion and hydrogen yield were analysed. It was found that the packing arrangement with spacing allows better distribution of the supplied heat. Due to the distance between the packing sections flow becomes more turbulent after each section, which intensifies the heat transfer and mixing of the mixture. The highest hydrogen yield is observed on catalytic packings located at a distance of 40 mm from each other and consisting of cylindrical catalysts. The most uniform pressure drop occurs at a packing arrangement without spacing. The increase in methane conversion observed with the increment in spacing distance, but the difference is insignificant. Therefore, the arrangement of catalysts with spacing can be used for the improvement of steam methane reforming process.

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15

Imada, Syota, Xiaobo Peng, Zexing Cai, Abdillah Sani Bin Mohd Najib, Masahiro Miyauchi, Hideki Abe, and Takeshi Fujita. "NiYAl-Derived Nanoporous Catalysts for Dry Reforming of Methane." Materials 13, no. 9 (April 27, 2020): 2044. http://dx.doi.org/10.3390/ma13092044.

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Dry reforming of methane can be used for suppressing the rapid growth of greenhouse gas emissions. However, its practical implementation generally requires high temperatures. In this study, we report an optimal catalyst for low-temperature dry reforming of methane with high carbon coking resistance synthesized from NiYAl alloy. A facile two-step process consisting of preferential oxidation and leaching was utilized to produce structurally robust nanoporous Ni metal and Y oxides from NiYAl4. The catalyst exhibited an optimal carbon balance (0.96) close to the ideal value of 1.0, indicating the optimized dry reforming pathway. This work proposes a facile route of the structural control of active metal/oxide sites for realizing highly active catalysts with long-term durability.

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16

Kuang, Xiao-Gang, Li Zhang, Yan-Lun Ren, and Xing-Wei Wang. "Process intensification of hydrogen production by steam reforming of methane over structured channel packing catalysts." E3S Web of Conferences 385 (2023): 02018. http://dx.doi.org/10.1051/e3sconf/202338502018.

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The industrial methane steam reforming reaction usually employs particulate catalyst that are easy to prepare and cost-effective, but suffer from problems such as high reactor pressure drop and low overall catalyst utilization. In this study, the Ni-Al2CaO4 powder prepared by the equal volume impregnation method was subjected to particle size control using a pressing method, and was made into catalyst particles of different sizes. Some of the catalysts were filled into honeycomb structures with cordierite and metal substrates, respectively, to prepare regular channel packing catalysts. The differences in methane steam reforming conversion rate, H2/CO selectivity, and overall pressure drop among the three catalysts were compared, and the influence of particle size and regular channel on reaction performance was systematically explored. The results showed that under the same conditions, as the catalyst particle size increased, the methane conversion rate and pressure drop increased. The regular channel packing catalysts with the two substrates showed similar pressure drop levels, but the metal substrate exhibited a higher methane conversion rate due to its excellent thermal conductivity. Compared with single-particle catalysts of the same size, the pressure drop of the metal substrate regular channel packing catalysts was reduced by more than 25%. Under the conditions of a gas hourly space velocity of 2000 h-1, a reaction temperature of 700 °C, and a water-to-carbon ratio of 3, the 40-60 mesh metal substrate regular packing catalysts showed a 7% increase in methane conversion rate, reaching 95.2%.

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17

Hu, Yun Hang, and Eli Ruckenstein. "Comment on “Dry reforming of methane by stable Ni–Mo nanocatalysts on single-crystalline MgO”." Science 368, no. 6492 (May 14, 2020): eabb5459. http://dx.doi.org/10.1126/science.abb5459.

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Song et al. (Reports, 14 February 2020, p. 777) ignore the reported efficient Ni/MgO solid-solution catalysts and overstate the novelty and importance of the Mo-doped Ni/MgO catalysts for the dry reforming of methane. We show that the Ni/MgO solid-solution catalyst that we reported in 1995, which is efficient and stable for the dry reforming, is superior to the Mo-doped Ni/MgO catalyst.

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18

Zhang, Chengyang, Renkun Zhang, Hui Liu, Qinhong Wei, Dandan Gong, Liuye Mo, Hengcong Tao, Sha Cui, and Luhui Wang. "One-Step Synthesis of Highly Dispersed and Stable Ni Nanoparticles Confined by CeO2 on SiO2 for Dry Reforming of Methane." Energies 13, no. 22 (November 15, 2020): 5956. http://dx.doi.org/10.3390/en13225956.

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Sintering and carbon deposition are the two main ways to deactivate Ni-based catalysts during methane reforming. Herein, a stable Ni-CeO2/SiO2(CSC) catalyst was prepared by a one-step colloidal solution combustion method (CSC) and used for dry reforming of methane. In the catalyst, the small Ni particles were confined by CeO2 particles and highly dispersed on the surface of SiO2, forming a spatial confinement structure with a rich Ni-CeO2 interface in the catalyst. The Ni-CeO2/SiO2(CSC) catalyst prepared by the one-step CSC method exhibited superior activity at 700 °C during dry reforming of methane, and the performance of the catalyst was stable after 20 h of reaction with only a small amount of carbon deposition present (1.8%). Due to the spatial confinement effect, Ni was stable and less than 5 nm during reaction. The small Ni particle size and rich Ni-CeO2 interface reduced the rate of carbon deposition. This colloidal combustion method could be applied to prepare stable metal-based catalysts with rich metal–oxide interfaces for high-temperature reactions.

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19

Saavedra Lopez, Johnny, Vanessa Lebarbier Dagle, Chinmay A. Deshmane, Libor Kovarik, Robert S. Wegeng, and Robert A. Dagle. "Methane and Ethane Steam Reforming over MgAl2O4-Supported Rh and Ir Catalysts: Catalytic Implications for Natural Gas Reforming Application." Catalysts 9, no. 10 (September 25, 2019): 801. http://dx.doi.org/10.3390/catal9100801.

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Solar concentrators employed in conjunction with highly efficient micro- and meso-channel reactors offer the potential for cost-effective upgrading of the energy content of natural gas, providing a near-term path towards a future solar-fuel economy with reduced carbon dioxide emissions. To fully exploit the heat and mass transfer advantages offered by micro- and meso-channel reactors, highly active and stable natural gas steam reforming catalysts are required. In this paper, we report the catalytic performance of MgAl2O4-supported Rh (5 wt.%), Ir (5 wt.%), and Ni (15 wt.%) catalysts used for steam reforming of natural gas. Both Rh- and Ir-based catalysts are known to be more active and durable than conventional Ni-based formulations, and recently Ir has been reported to be more active than Rh for methane steam reforming on a turnover basis. Thus, the effectiveness of all three metals to perform natural gas steam reforming was evaluated in this study. Here, the Rh- and Ir-supported catalysts both exhibited higher activity than Ni for steam methane reforming. However, using simulated natural gas feedstock (94.5% methane, 4.0% ethane, 1.0% propane, and 0.5% butane), the Ir catalyst was the least active (on a turnover basis) for steam reforming of higher hydrocarbons (C2+) contained in the feedstock when operated at <750 °C. To further investigate the role of higher hydrocarbons, we used an ethane feed and found that hydrogenolysis precedes the steam reforming reaction and that C–C bond scission over Ir is kinetically slow compared to Rh. Catalyst durability studies revealed the Rh catalyst to be stable under steam methane reforming conditions, as evidenced by two 100-hour duration experiments performed at 850 and 900 °C (steam to carbon [S/C] molar feed ratio = 2.0 mol). However, with the natural gas simulant feed, the Rh catalyst exhibited catalyst deactivation, which we attribute to coking deposits derived from higher hydrocarbons contained in the feedstock. Increasing the S/C molar feed ratio from 1.5 to 2.0 reduced the deactivation rate and stable catalytic performance was demonstrated for 120 h when operated at 850 °C. However, catalytic deactivation was observed when operating at 900 °C. While improvements in steam reforming performance can be achieved through choice of catalyst composition, this study also highlights the importance of considering the effect of higher hydrocarbons contained in natural gas, operating conditions (e.g., temperature, S/C feed ratio), and their effect on catalyst stability. The results of this study conclude that a Rh-supported catalyst was developed that enables very high activities and excellent catalytic stability for both the steam reforming of methane and other higher hydrocarbons contained in natural gas, and under conditions of operation that are amendable to solar thermochemical operations.

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20

Khan, Wasim Ullah, Mohammad Rizwan Khan, Rosa Busquets, and Naushad Ahmad. "Contribution of Oxide Supports in Nickel-Based Catalytic Elimination of Greenhouse Gases and Generation of Syngas." Energies 14, no. 21 (November 4, 2021): 7324. http://dx.doi.org/10.3390/en14217324.

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Carbon dioxide and/or dry methane reforming serves as an effective pathway to mitigate these greenhouse gases. This work evaluates different oxide supports including alumina, Y-zeolite and H-ZSM-5 zeolite for the catalysis of dry reforming methane with Nickel (Ni). The composite catalysts were prepared by impregnating the supports with Ni (5%) and followed by calcination. The zeolite supported catalysts exhibited more reducibility and basicity compared to the alumina supported catalysts, this was assessed with temperature programmed reduction using hydrogen and desorption using carbon dioxide. The catalytic activity, in terms of CH4 conversion, indicated that 5 wt% Ni supported on alumina exhibited higher CH4 conversion (80.5%) than when supported on Y-zeolite (71.8%) or H-ZSM-5 (78.5%). In contrast, the H-ZSM-5 catalyst led to higher CO2 conversion (87.3%) than Y-zeolite (68.4%) and alumina (83.9%) supported catalysts. The stability tests for 9 h time-on-stream showed that Ni supported with H-ZSM-5 had less deactivation (just 2%) due to carbon deposition. The characterization of spent catalysts using temperature programmed oxidation (O2-TPO), X-ray diffraction (XRD) and thermo-gravimetric analysis (TGA) revealed that carbon deposition was a main cause of deactivation and that it occurred in the lowest degree on the Ni H-ZSM-5 catalyst.

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21

Yuan, Bo, Tao Zhu, Yiwei Han, Xueli Zhang, Meidan Wang, and Chen Li. "Deactivation Mechanism and Anti-Deactivation Measures of Metal Catalyst in the Dry Reforming of Methane: A Review." Atmosphere 14, no. 5 (April 23, 2023): 770. http://dx.doi.org/10.3390/atmos14050770.

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In recent decades, the massive emission of greenhouse gases, such as carbon dioxide and methane, into the atmosphere has had a serious impact on the ecological environment. The dry reforming of carbon dioxide and methane to syngas cannot only realize the resource utilization of methane and carbon dioxide but also reduce global climate change. It is of great significance in carbon emission reduction. Owing to the dry reforming of methane (DRM) being a strongly endothermic reaction, it needs to be carried out under high-temperature conditions. It makes the catalyst have problems of the sintering of metal, carbon deposition, and poisoning. This article revolves around the problem of catalyst deactivation during the DRM reaction. It expands upon the thermodynamics and mechanisms of the DRM reaction, analyzes the causes of metal catalyst deactivation due to carbon deposition, sintering, and poisoning, and summarizes how the active components, supports, and additives of metal catalysts restrain the DRM catalyst deactivation during the reaction. The analysis revealed that changing the type and size of the active metal, adjusting the properties of the support, and adding additives can further regulate the dispersion of the active component, the interaction between the active component and the support, the oxygen vacancies of the support, and the acidity and basicity of the catalyst surface, ultimately achieving control over the metal catalyst’s resistance to sintering, carbon deposition, and sulfur poisoning. In addition, it discusses the application of metal catalysts in photothermal and plasma-catalyzed DRM. Finally, it outlines the prospects for research on metal catalysts for the DRM.

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22

Hua, Wei, Yong Chuan Dai, and Hong Tao Jiang. "Noble Metal Catalysts for Methane Reforming in Material Application Engineering." Advanced Materials Research 648 (January 2013): 83–87. http://dx.doi.org/10.4028/www.scientific.net/amr.648.83.

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Reforming of methane is an important route to produce sygas. In this paper, recent progresses of noble metals (Rh, Ru, Ir, Pt, Pd) catalysts for methane reforming in material application engineering is reviewed. The discussion mainly focuses on catalytic performance of noble metal catalysts or noble metal promoted Ni catalysts in methane reforming reaction. Effects of noble metals, supports and preparation methods on the catalytic activity, selectivity, coke deposition and stability of catalysts have been briefly summarized. In conclusion, Rh as active component, Pd as material for membrane reactor, Pt or Rh as promoters for Ni catalysts, all gave high CH4 conversion, improving catalytic performance.

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23

Lanre, Mahmud S., Ahmed E. Abasaeed, Anis H. Fakeeha, Ahmed A. Ibrahim, Abdulrahman S. Al-Awadi, Abdulrahman bin Jumah, Fahad S. Al-Mubaddel, and Ahmed S. Al-Fatesh. "Lanthanum–Cerium-Modified Nickel Catalysts for Dry Reforming of Methane." Catalysts 12, no. 7 (June 29, 2022): 715. http://dx.doi.org/10.3390/catal12070715.

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The catalyst MNi0.9Zr0.1O3 (M = La, Ce, and Cs) was prepared using the sol–gel preparation technique investigated for the dry reforming of methane reaction to examine activity, stability, and H2/CO ratio. The lanthanum in the catalyst LaNi0.9Zr0.1O3 was partially substituted for cerium and zirconium for yttrium to give La0.6Ce0.4Ni0.9Zr0.1-xYxO3 (x = 0.05, 0.07, and 0.09). The La0.6Ce0.4Ni0.9Zr0.1-xYxO3 catalyst’s activity increases with an increase in yttrium loading. The activities of the yttrium-modified catalysts La0.6Ce0.4Ni0.9Zr0.03Y0.07O3 and La0.6Ce0.4Ni0.9Zr0.01Y0.09O3 are higher than the unmodified La0.6Ce0.4Ni0.9Zr0.1O3 catalyst, the latter having methane and carbon dioxide conversion values of 84% and 87%, respectively, and the former with methane and carbon dioxide conversion values of 86% and 90% for La0.6Ce0.4Ni0.9Zr0.03Y0.07O3 and 89% and 91% for La0.6Ce0.4Ni0.9Zr0.01Y0.09O3, respectively. The BET analysis depicted a low surface area of samples ranging from 2 to 9m2/g. The XRD peaks confirmed the formation of a monoclinic phase of zirconium. The TPR showed that apparent reduction peaks occurred in moderate temperature regions. The TGA curve showed weight loss steps in the range 773 K–973 K, with CsNi0.9Zr0.1O3 carbon deposition being the most severe. The coke deposit on La0.6Ce0.4Ni0.9Zr0.1O3 after 7h time on stream (TOS) was the lowest, with 20% weight loss. The amount of weight loss increases with a decrease in zirconium loading.

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Macario, A., P. Frontera, S. Candamano, F. Crea, P. De Luca, and P. L. Antonucci. "Nanostructured Catalysts for Dry-Reforming of Methane." Journal of Nanoscience and Nanotechnology 19, no. 6 (June 1, 2019): 3135–47. http://dx.doi.org/10.1166/jnn.2019.16651.

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The manuscript deals on the main progress achieved by global scientific research on the development of nanostructured catalysts for dry-reforming reaction. The importance to have a global vision on this topic is strictly related to the most currently and important challenges in the sustainable energy production. In fact, dry-reforming is one of the few known processes in which greenhouse gases are utilized as reactants (methane and carbon dioxide) to produce syngas. Syngas represents the basis for liquid fuel production by Fischer-Tropsch process. In this broad and current context, the catalyst development plays a pivotal role due to its great influence on efficiency, and therefore on the costs, of the whole process. Several are the aspects to consider during the catalyst design: role of metal, interaction between metal and support, role of promoters and resistance to the coke deactivation. These issues, as well as the thermodynamics of the process, are the main aspects of which this review speaks about.

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Wysocka, Izabela, Jan Hupka, and Andrzej Rogala. "Catalytic Activity of Nickel and Ruthenium–Nickel Catalysts Supported on SiO2, ZrO2, Al2O3, and MgAl2O4 in a Dry Reforming Process." Catalysts 9, no. 6 (June 17, 2019): 540. http://dx.doi.org/10.3390/catal9060540.

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Анотація:

Dry reforming of methane (DRM) is an eco-friendly method of syngas production due to the utilization of two main greenhouse gases—methane and carbon dioxide. An industrial application of methane dry reforming requires the use of a catalyst with high activity, stability over a long time, and the ability to catalyze a reaction, leading to the needed a hydrogen/carbon monoxide ratio. Thus, the aim of the study was to investigate the effect of support and noble metal particles on catalytic activity, stability, and selectivity in the dry reforming process. Ni and Ni–Ru based catalysts were prepared via impregnation and precipitation methods on SiO2, ZrO2, Al2O3, and MgAl2O4 supports. The obtained catalysts were characterized using X-ray diffractometry (XRD), inductively coupled plasma optical emission spectrometry (ICP-OES), Brunauer–Emmett–Teller (BET) specific surface area, and elemental carbon-hydrogen-nitrogen-sulphur analysis (CHNS) techniques. The catalytic activity was investigated in the carbon dioxide reforming of a methane process at 800 °C. Catalysts supported on commercial Al2O3 and spinel MgAl2O4 exhibited the highest activity and stability under DRM conditions. The obtained results clearly indicate that differences in catalytic activity result from the dispersion, size of an active metal (AM), and interactions of the AM with the support. It was also found that the addition of ruthenium particles enhanced the methane conversion and shifted the H2/CO ratio to lower values.

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Asencios, Yvan J. O., Kariny F. M. Elias, Andressa de Zawadzki, and Elisabete M. Assaf. "Synthesis-Gas Production from Methane over Ni/CeO2 Catalysts Synthesized by Co-Precipitation Method in Different Solvents." Methane 1, no. 2 (March 23, 2022): 72–81. http://dx.doi.org/10.3390/methane1020007.

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Анотація:

Ni/CeO2 catalysts were synthesized by the coprecipitation method in a basic medium, using different solvents: water, methanol, ethanol, and isopropanol (Ni content, 10% wt.). These catalysts were tested in the production of syngas through the oxidative reforming of methane (ORM), and partial oxidation of methane (POM). The results of this research demonstrated that the use of alcohols (methanol, ethanol, and isopropanol) during the preparation of the Ni/CeO2 catalysts by the coprecipitation method, improved their characteristics such as crystallite size (nm), surface area (m2·g−1), and reducibility (measured by H2-TPR) that influenced on their catalytic performance in ORM and POM reactions. The best solvent of this study was isopropanol. The use of alcohols (methanol, ethanol, isopropanol) in the co-precipitation method led to the formation of filamentous carbon on the catalyst after the reactions. The catalyst synthesized in the water proved to be inefficient in the POM and ORM reactions and led to the formation of amorphous carbon after the reactions.

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Mierczynski, Pawel, Natalia Stępińska, Magdalena Mosinska, Karolina Chalupka, Jadwiga Albinska, Waldemar Maniukiewicz, Jacek Rogowski, Magdalena Nowosielska, and Malgorzata I. Szynkowska. "Hydrogen Production via the Oxy-Steam Reforming of LNG or Methane on Ni Catalysts." Catalysts 10, no. 3 (March 20, 2020): 346. http://dx.doi.org/10.3390/catal10030346.

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Ni catalysts supported on ZrO2, 5%CeO2-ZrO2, and 5%La2O3-ZrO2 were prepared via the impregnation method and tested in the oxy-steam reforming of methane and liquified natural gas (LNG). All tested catalysts exhibited high catalytic activity in the studied process at 700 and 900 °C. The improvement of the stability of Ni catalysts after the addition of CeO2 oxide in the studied oxy-steam reforming of LNG process was confirmed. In addition, high activity and selectivity towards hydrogen was proven in the oxy-steam reforming process at 900 °C over a 20%Ni/5%CeO2-ZrO2 catalyst. It was also proved that the addition of CeO2 onto a ZrO2 carrier leads to a decrease in the NiO and metallic Ni crystallite sizes that were detected by the X-Ray diffraction (XRD) technique. The solid solution formation between NiO and ZrO2 and/or NiO and CeO2 was proved. Superior reactivity in the oxy-steam reforming of CH4 and the LNG process exhibited a 20%Ni/ZrO2 catalyst, which showed the highest methane conversions at 500 and 600 °C, equal to 63% and 89%, respectively. In addition, also in the case of the LNG reforming reaction, the most active catalyst was the 20%Ni/ZrO2 system, which demonstrated 46.3% and 76.9% of the methane conversion value at 500 and 600 °C and the total conversion of others hydrocarbons (ethane, propane and butane). In addition, this catalytic system exhibited the highest selectivity towards hydrogen formation in the oxy-steam reforming of the LNG reaction equal to 71.2% and 71.3% at 500 and 600 °C, respectively. The highest activity of this system can be explained by the uniform distributions of Ni species and their highest concentration compared to the rest of the monometallic Ni catalysts. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) results also confirmed a strong interaction of NiO with ZrO2 in the case of the 20%Ni/ZrO2 catalysts. The presence of selected NiZrO+ ions emitted from the investigated surface of the 20%Ni/ZrO2 system was detected.

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Gonçalves, Juliana F., and Mariana M. V. M. Souza. "Ni/x%Nb2O5/Al2O3 Catalysts Prepared via Coprecipitation-Wet Impregnation Method for Methane Steam Reforming." Current Catalysis 9, no. 1 (September 10, 2020): 80–89. http://dx.doi.org/10.2174/2211544708666190423130340.

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Background: Hydrogen has been considered the energy source of the future and one of the processes for its production is the methane steam reforming. The catalyst used industrially is Ni/Al2O3 and the addition of promoter oxides can be an alternative to improve the performance of this catalyst, which suffers from coke formation and sintering. Objective: Evaluate the role of niobia on catalytic activity and stability. Methods: Ni/x%Nb2O5/Al2O3 (x = 5, 10 and 20) catalysts were synthesized via coprecipitation-wet impregnation method and characterized by X-ray fluorescence (XRF), N2 adsorption-desorption, X-ray diffraction (XRD), temperature- programmed reduction (TPR), temperature-programmed desorption of ammonia (TPD-NH3), etc. Finally, the catalysts were tested for methane steam reforming reaction. Results: All niobia-doped catalysts presented similar values of methane conversion and when comparing with Ni-Al, the addition of niobia slightly improved the methane conversion. In the stability test at 800oC, all doped and non-doped catalysts did not deactivate during the 24 h of reaction. Conclusion: The addition of 10 and 20 wt.% of niobia had a significant promoter effect over Ni/Al2O3 catalyst in terms of activity and stability at 800 oC and the sample with 20 wt.% of niobia presented lower coke formation.

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Sellam, Djamila, Kahina Ikkour, Sadia Dekkar, Hassiba Messaoudi, Taous Belaid, and Anne Cécile Roger. "CO2 Reforming of Methane over LaNiO3 Perovskite Supported Catalysts: Influence of Silica Support." Bulletin of Chemical Reaction Engineering & Catalysis 14, no. 3 (December 1, 2019): 568. http://dx.doi.org/10.9767/bcrec.14.3.3472.568-578.

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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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Azeem, Subhan, Rabya Aslam, and Mahmood Saleem. "Dry Reforming of Methane with Mesoporous Ni/ZrO2 Catalyst." International Journal of Chemical Engineering 2022 (December 16, 2022): 1–13. http://dx.doi.org/10.1155/2022/3139696.

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Анотація:

Dry reforming of methane has exhibited significant environmental benefits as it utilizes two major greenhouse gases (CO2 and CH4) to produce synthesis gas, a major building block for hydrocarbons. This process has gained industrial attention as catalyst deactivation due to coke deposition being a major hindrance. The present study focuses on the dry reforming of methane over Ni-supported mesoporous zirconia support. Ni metal was loaded over in-house synthesized mesoporous zirconia within the 0–15 wt% range using the wet impregnation method. The physicochemical properties of the synthesized catalysts were studied using various characterization techniques, namely, XRD, SEM, FTIR, TGA, and N2 adsorption-desorption techniques. The activity of all the catalysts was evaluated at 750°C and gas hourly space velocity (GHSV) of 72000 ml/h/gcat for 9 hours (540 min). The deactivation factor indicating a loss in conversion with time is reported for each catalyst. 10 wt% Ni/ZrO2 showed the highest feed conversion of about 68.8% for methane and 70.2% for carbon dioxide and the highest stability (15.1% deactivation factor and 21% weight loss) for dry reforming of methane to synthesis gas.

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Fasolini, Andrea, Silvia Ruggieri, Cristina Femoni, and Francesco Basile. "Highly Active Catalysts Based on the Rh4(CO)12 Cluster Supported on Ce0.5Zr0.5 and Zr Oxides for Low-Temperature Methane Steam Reforming." Catalysts 9, no. 10 (September 25, 2019): 800. http://dx.doi.org/10.3390/catal9100800.

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Анотація:

Syngas and Hydrogen productions from methane are industrially carried out at high temperatures (900 °C). Nevertheless, low-temperature steam reforming can be an alternative for small-scale plants. In these conditions, the process can also be coupled with systems that increase the overall efficiency such as hydrogen purification with membranes, microreactors or enhanced reforming with CO2 capture. However, at low temperature, in order to get conversion values close to the equilibrium ones, very active catalysts are needed. For this purpose, the Rh4(CO)12 cluster was synthetized and deposited over Ce0.5Zr0.5O2 and ZrO2 supports, prepared by microemulsion, and tested in low-temperature steam methane reforming reactions under different conditions. The catalysts were active at 750 °C at low Rh loadings (0.05%) and outperformed an analogous Rh-impregnated catalyst. At higher Rh concentrations (0.6%), the Rh cluster deposited on Ce0.5Zr0.5 oxide reached conversions close to the equilibrium values and good stability over long reaction time, demonstrating that active phases derived from Rh carbonyl clusters can be used to catalyze steam reforming reactions. Conversely, the same catalyst suffered from a fast deactivation at 500 °C, likely related to the oxidation of the Rh phase due to the oxygen-mobility properties of Ce. Indeed, at 500 °C the Rh-based ZrO2-supported catalyst was able to provide stable results with higher conversions. The effects of different pretreatments were also investigated: at 500 °C, the catalysts subjected to thermal treatment, both under N2 and H2, proved to be more active than those without the H2 treatment. In general, this work highlights the possibility of using Rh carbonyl-cluster-derived supported catalysts in methane reforming reactions and, at low temperature, it showed deactivation phenomena related to the presence of reducible supports.

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Saad, M. A., N. H. Abdurahman, Rosli Mohd Yunus, Mohammed Kamil, and Omar I. Awad. "An Overview of Reforming Technologies and the Effect of Parameters on the Catalytic Performance of Mesoporous Silica/Alumina Supported Nickel Catalysts for Syngas Production by Methane Dry Reforming." Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) 13, no. 4 (June 2, 2020): 303–22. http://dx.doi.org/10.2174/2405520413666200313130420.

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Анотація:

Synthetic gas - a combination of (H2) and (CO) - is an important chemical intermediate for the production of liquid hydrocarbon, olefin, gasoline, and other valuable chemicals. Several reforming methods that use steam, carbon dioxide, and oxygen in the presence of various catalytic systems have been extensively investigated, and this paper reviews the recent research on the state-of-the-art of reforming technologies and the effect of parameters on the catalytic activity of mesoporous silica/alumina supported nickel catalysts for syngas production by methane dry reforming. First, we provide an overview of reforming technologies, including methane dry reforming, steam methane reforming, partial oxidation of CH4, and auto thermal reforming of CH4. Then, we review the literature on dry reforming catalysts. Next, we describe recent findings on the effect of parameters on the catalytic activity of mesoporous silica/alumina supported nickel catalysts for syngas production. Finally, we make proposals for future research. This study can help achieve a better understanding of the reforming technologies and the effects of parameters on catalytic performance for syngas production, thus contributing to the development of green technologies.

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Rakib, Abdelmajid, Cédric Gennequin, Thierry Dhainaut, Sylvain Ringot, Antoine Aboukaïs, and Edmond Abi-Aad. "Promoting Effect of CeO₂ Addition on Activity and Catalytic Stability in Steam Reforming of Methane over Ni/Al₂O₃." Advanced Materials Research 324 (August 2011): 153–56. http://dx.doi.org/10.4028/www.scientific.net/amr.324.153.

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Анотація:

Hydrogen production by steam reforming of methane was studied over Ni catalysts supported on CeO2, Al2O3 and CeO2-Al2O3. These catalysts were prepared using the impregnation method and characterized by XRD. The effect of CeO2 promoter on the catalytic performance of Ni/Al2O3 catalyst for methane steam reforming reaction was investigated. In fact, CeO2 had a positive effect on the catalytic activity in this reaction. Experimental results demonstrated that Ni/CeO2-Al2O3 catalyst showed excellent catalytic activity and high reaction performance. In addition, the effects of reaction temperature and metal content on the conversion of CH4 and H2/CO ratio were also investigated. Results indicated that CH4 conversion increased significantly with the increase of the reaction temperature and metal content.

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A. Ibrahim, Ahmed, Ashraf Amin, Ahmed S. Al-Fatesh, Nadavala Siva Kumar, Samsudeen Olajide Kasim, Abdulrhman S. Al-Awadi, Ahmed M. El-Toni, Ahmed Elhag Abasaeed, and Anis H. Fakeeha. "Nanosized Ni/SBA-15 Catalysts for CO2 Reforming of CH4." Applied Sciences 9, no. 9 (May 10, 2019): 1926. http://dx.doi.org/10.3390/app9091926.

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Ni, Co, and Co–Ni bimetallic catalysts supported over SBA-15 and over SBA-15 doped with Zn or Ce oxides were prepared and tested in a methane dry reforming reaction. The loading of the metals in the catalyst was 5 wt % for either mono or bimetallic catalysts. The prepared catalysts were tested in a continuous-flow fixed-bed reactor at 800 °C under atmospheric pressure. XRD, TPR, TPD, and SEM characterization techniques were employed to investigate the catalytic properties of fresh catalysts. SEM and TGA were used to study the catalytic properties of spent catalysts. A remarkable effect on the reduction properties and catalytic performance of catalysts was observed after adding Zn and Ce. Over an 8 h test, Ni/SBA-15 showed the best activity and stability. The conversion was 90% for CH4 and CO2. Co–Ni/SBA-15 and Co–Ni/Ce–SBA-15 have shown a reasonable activity and stability. Selectivity of the Ni/SBA-15 catalyst was higher than all other catalysts as indicated by the H2/CO ratio. Co/SBA-15 and Co–Ni/Zn–SBA-15 showed a low activity and selectivity. TPD–NH3 profiles indicated that doping SBA-15 with Ce and/or Zn increased the catalyst acidic sites. Ni/SBA-15 is an excellent potential catalyst for commercial methane dry reforming processes.

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Hossain, M. Anwar, Bamidele Victor Ayodele, Chin Kui Cheng, and Maksudur R. Khan. "Syngas Production from Catalytic CO2 Reforming of CH4 over CaFe2O4 Supported Ni and Co Catalysts: Full Factorial Design Screening." Bulletin of Chemical Reaction Engineering & Catalysis 13, no. 1 (April 2, 2018): 57. http://dx.doi.org/10.9767/bcrec.13.1.1197.57-73.

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Анотація:

In this study, the potential of dry reforming reaction over CaFe2O4 supported Ni and Co catalysts were investigated. The Co/CaFe2O4 and Ni/CaFe2O4 catalysts were synthesized using wet impregnation method by varying the metal loading from 5-15 %. The synthesized catalysts were tested in methane dry reforming reaction at atmospheric pressure and reaction temperature ranged 700-800 oC. The catalytic performance of the catalysts based on the initial screening is ranked as 5%Co/CaFe2O4 < 10%Co/CaFe2O4 < 5%Ni/CaFe2O4 < 10%Ni/CaFe2O4 according to their performance. The Ni/CaFe2O4 catalyst was selected for further investigation using full factorial design of experiment. The interaction effects of three factors namely metal loading (5-15 %), feed ratio (0.4-1.0), and reaction temperature (700-800 oC) were evaluated on the catalytic activity in terms of CH4 and CO2 conversion as well as H2 and CO yield. The interaction between the factors showed significant effects on the catalyst performance at metal loading, feed ratio and reaction temperature of 15 %, 1.0, and 800 oC. respectively. The 15 wt% Ni/CaFe2O4 was subsequently characterized by Thermogravimetric (TGA), X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray Spectroscopy (EDX), X-ray Photoelectron Spectroscopy (XPS), N2-physisorption, Temperature Programmed Desorption (TPD)-NH3, TPD-CO2, and Fourier Transform Infra Red (FTIR) to ascertain its physiochemical properties. This study demonstrated that the CaFe2O4 supported Ni catalyst has a good potential to be used for syngas production via methane dry reforming. Copyright © 2018 BCREC Group. All rights reservedReceived: 5th May 2017; Revised: 8th August 2017; Accepted: 9th August 2017; Available online: 22nd January 2018; Published regularly: 2nd April 2018How to Cite: Hossain, M.A., Ayodele, B.V., Cheng, C.K., Khan, M.R. (2018). Syngas Production from Catalytic CO2 Reforming of CH4 over CaFe2O4 Supported Ni and Co Catalysts: Full Factorial Design Screening. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (1): 57-74 (doi:10.9767/bcrec.13.1.1197.57-74)

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Singh, Satyapaul A., Yaddanapudi Varun, Priyanka Goyal, I. Sreedhar, and Giridhar Madras. "Feed Effects on Water–Gas Shift Activity of M/Co3O4-ZrO2 (M = Pt, Pd, and Ru) and Potassium Role in Methane Suppression." Catalysts 13, no. 5 (May 4, 2023): 838. http://dx.doi.org/10.3390/catal13050838.

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Анотація:

Water–gas shift (WGS) is an industrial process to tackle CO abatement and H2 upgradation. The syngas (CO and H2 mixture) obtained from steam or dry reformers often has unreacted (from dry reforming) or undesired (from steam reforming) CO2, which is subsequently sent to downstream WGS reactor for H2 upgradation. Thus, industrial processes must deal with CO2 and H2 in the reformate feed. Achieving high CO2 or H2 selectivities become challenging due to possible CO and CO2 methanation reactions, which further increases the separation costs to produce pure H2. In this study, M/Co3O4-ZrO2 (M = Ru, Pd and Pt) catalysts were prepared using sonochemical synthesis. The synthesized catalysts were tested for WGS activity under three feed conditions, namely, Feed A (CO and steam), Feed B (CO, H2 and steam) and Feed C (CO, H2, CO2 and steam). All the catalysts gave zero methane selectivity under Feed A conditions, whereas the methane selectivity was significant under Feed B and C conditions. Among all catalysts, PtCZ was found to be the best performing catalyst in terms of CO conversion and CO2 selectivity. However, it still suffered with low but significant methane selectivity. This best performing catalyst was further modified with an alkali component, potassium to suppress undesirable methane selectivity. All the catalysts were well characterized with BET, SEM, TEM to confirm the structural properties and effective doping of the noble metals. Additionally, the apparent activation energies were obtained to showcase the best catalyst.

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Yang, Hui, Hui Wang, Lisha Wei, Yong Yang, Yong-Wang Li, Xiao-dong Wen, and Haijun Jiao. "Simple mechanisms of CH₄ reforming with CO₂ and H₂O on a supported Ni/ZrO₂ catalyst." Physical Chemistry Chemical Physics 23, no. 46 (2021): 26392–400. http://dx.doi.org/10.1039/d1cp04048k.

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Анотація:

To understand the metal–support interaction of oxide supported transition metal catalysts, we computed the reaction mechanisms of dry and steam reforming of methane on a tetragonal ZrO2(101) supported Ni catalyst.

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Fakeeha, A. H., A. S. Al–Fatesh, and A. E. Abasaeed. "Ni/Y- Zeolite Catalysts for Carbon Dioxide Reforming of Methane." Advanced Materials Research 550-553 (July 2012): 325–28. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.325.

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Carbon deposits play a crucial role in the performance of catalysts, in terms of controlling both reaction selectivity and activity, this is most often manifest through catalyst deactivation. Understanding the structure and electronic properties of the carbon deposits formed on the surface of a catalyst is therefore an importance key. In this study the catalytic performance of Ni based on Y-Zeolite (CBV300) prepared by incipient wetness impregnation. The prepared catalyst was tested in a micro tubular reactor using temperature ranges of 500, 600 and 700 °C at atmospheric pressure, using a total flow rate of 36 ml/min consisting of 2 ml/min of N2, 17 ml/min of CO2and 17 ml/min of CH4. The calcination was carried out in the range of 500–900 °C. The catalyst is activated inside the reactor using hydrogen gas.The conversion of CH4observed over 5wt%Ni/ Y-Zeolite at 700 °C were 59.6%. The supported Ni catalysts were characterized by BET and TG/DTA techniques.

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Ewbank, Jessica L., Libor Kovarik, Christian C. Kenvin, and Carsten Sievers. "Effect of preparation methods on the performance of Co/Al2O3 catalysts for dry reforming of methane." Green Chem. 16, no. 2 (2014): 885–96. http://dx.doi.org/10.1039/c3gc41782d.

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Анотація:

Co/Al₂O₃ catalysts were synthesized by dry impregnation and controlled adsorption. The effect of catalyst preparation methods on their performance in methane dry reforming was studied.

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40

Samojeden, Bogdan, Marta Kamienowska, Armando Izquierdo Colorado, Maria Elena Galvez, Ilona Kolebuk, Monika Motak, and Patrick Da Costa. "Novel Nickel- and Magnesium-Modified Cenospheres as Catalysts for Dry Reforming of Methane at Moderate Temperatures." Catalysts 9, no. 12 (December 14, 2019): 1066. http://dx.doi.org/10.3390/catal9121066.

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Анотація:

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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Lyu, Linghui, Yunxing Han, Qingxiang Ma, Shengene Makpal, Jian Sun, Xinhua Gao, Jianli Zhang, Hui Fan, and Tian-Sheng Zhao. "Fabrication of Ni-Based Bimodal Porous Catalyst for Dry Reforming of Methane." Catalysts 10, no. 10 (October 20, 2020): 1220. http://dx.doi.org/10.3390/catal10101220.

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Анотація:

Dry reforming of methane (DRM) can effectively convert two greenhouse gases into high-valued chemicals, in which the syngas produced by the reaction can be directly used as raw gases for Fischer–Tropsch synthesis and methanol synthesis. Ni-based catalysts for the DRM reaction with comparable initial activity to noble metals are the focus of most researchers, but their poor carbon deposition resistance easily causes their low stability. More importantly, the nickel loading will affect the catalytic activity and carbon deposition resistance of the catalyst. Herein, a series of Ni/Al2O3 catalysts with bimodal pores was prepared and characterized by X-ray diffraction (XRD), N2 physical adsorption–desorption, H2-temperature programmed reduction (H2-TPR), temperature programmed hydrogenation (TPH), Raman, and thermogravimetric analysis (TG). The results show that the interesting bimodal structure catalysts could provide a high surface area and contribute to the mass transfer. Besides, the catalytic performance of the DRM reaction is sensitive to nickel loadings. In this study, the Ni/Al2O3 catalyst with nickel loadings of 6% and 8% exhibited excellent catalytic activity and carbon deposition resistance. These findings will provide a new strategy to design a highly efficient and stable heterogeneous catalyst for industry.

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42

Shi, Yu, Shiwei Wang, Yiming Li, Fan Yang, Hongbo Yu, Yuting Chu, Tong Li, and Hongfeng Yin. "Improving Anti-Coking Properties of Ni/Al2O3 Catalysts via Synergistic Effect of Metallic Nickel and Nickel Phosphides in Dry Methane Reforming." Materials 15, no. 9 (April 22, 2022): 3044. http://dx.doi.org/10.3390/ma15093044.

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A series of NiP-x/Al2O3 catalysts containing different ratio of metallic nickel to nickel phosphides, prepared by varying Ni/P molar ratio of 4, 3, 2 through a co-impregnation method, were employed to investigate the synergistic effect of metallic nickel-nickel phosphides in dry methane reforming reaction. The Ni/Al2O3 catalyst indicates good activity along with severe carbon deposition. The presence of phosphorus increases nickel dispersion as well as the interaction between nickel and alumina support, which results in smaller nickel particles. The co-existence of metallic nickel and nickel phosphides species is confirmed at all the P contained catalysts. Due to the relative stronger CO2 dissociation ability, the NiP-x/Al2O3 catalysts indicate obvious higher resistance of carbon deposition. Furthermore, because of good balance between CH4 dissociation and CO2 dissociation, NiP-2/Al2O3 catalyst exhibits best resistance of carbon deposition, few carbon depositions were formed after 50 h of dry methane reforming.

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43

Abdelsadek, Z., S. Gonzalez-Cortes, O. Cherifi, D. Halliche, and PJ Masset. "Reduction effect on the catalytic performances of NiAl-SPC takovite catalysts in syngas synthesis process." IOP Conference Series: Earth and Environmental Science 1167, no. 1 (May 1, 2023): 012031. http://dx.doi.org/10.1088/1755-1315/1167/1/012031.

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Abstract In the downstream of the Oil & Gas industry and decline in oil production, the NiAl-HT derived hydrotalciteis a candidate as catalyst to produce syngas in the methane dry reforming process. Hydrotalcite are lamellar compounds of general formulation[M1-x 2+ Mx 3+ (OH) 2]x+[An-] x/n .m H2Owhere the ionic or cationic character can be tuned by the choice of the metal nature and oxidation degree. NiAl-SPC samples were obtained by coprecipitation at constant alkaline pH, then the product was thermal treated at 450°C for 6h to obtain mixed oxides phases. Samples prior and after calcination were characterized by XRD, ICP, BET, FTIR, SEM, TEM, TPR, TGA/DTA and Raman. Catalysts were examined in CO2 dry reforming of methane to examine the influence and the role of the reducibility ability on the catalytic reactivity and stability of NiAl-SPC hydrotalcite generics. They were reduced at 500°C, 600°C, and 700°Cfor 1h to evaluate the effect of its morphology changes on the carbon dioxide reforming of methane carried out at 700°C versus time on stream. It was shown that the reduction conditions strongly influence the reactivity of Ni metallic active phase catalyst, catalytic selectivity and its resistance to carbone deposit for methane reforming by carbon dioxide.This study proposes a further understanding of the synthesis, effects of additives and treatment of hydrotalcite as a catalyst for the DRM reaction. This knowledge will also be beneficial for the development of catalysts for other high temperature industrial applications (ammonia cracking, alcohol to hydrogen conversion...) and for longer term applications such as drug delivery or energy storage materials.

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44

Yakovenko, R. E., V. B. Ilyin, A. P. Savostyanov, I. N. Zubkov, A. V. Dulnev, and O. A. Semyonov. "Conversion of Liquefied Hydrocarbon Gases on Commercial Nickel Catalysts." Kataliz v promyshlennosti 19, no. 6 (November 14, 2019): 455–64. http://dx.doi.org/10.18412/1816-0387-2019-6-455-464.

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The two-step conversion of industrial liquefied hydrocarbon gases (LHG) on NIAP-07-01 (NKM-1) and NIAP-03-01 catalysts for the production of hydrogen-containing gases was investigated. The experiments were carried out in flow reactors with a fixed catalyst bed at a pressure of 0.1 MPa under the following conditions: temperature 350–450 °C, gas hourly space velocity (GHSV) 1000–3000 h–1, steam-gas ratio 4 : 1–8 : 1 (pre-reforming); and temperature 700 °C, GHSV 2000 h–1, air-gas ratio 1.2 : 1 (steam-air reforming). Under the studied conditions, the concentrations of components of the converted gas correspond to the equilibrium values calculated within the Peng-Robinson model. The conversion of methane homologs in the pre-reforming step was found to be virtually 100 %; therewith, the methane concentration reached 32–54 %, and that of hydrogen, 24–47 %. To prevent the formation of elemental carbon (carbonization), pre-reforming of hydrocarbon gases with a high methane equivalent should be performed at H2O : C > 2. In the two-step reforming, the yield of hydrogen-containing gas reaches 15.6 m3 from 1 m3 of the initial LHG with the hydrogen content 41.81 %, and the total content of CO and H2 exceeds 52 %.

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45

Abiev, Rufat Sh, Dmitry A. Sladkovskiy, Kirill V. Semikin, Dmitry Yu Murzin, and Evgeny V. Rebrov. "Non-Thermal Plasma for Process and Energy Intensification in Dry Reforming of Methane." Catalysts 10, no. 11 (November 22, 2020): 1358. http://dx.doi.org/10.3390/catal10111358.

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Plasma-assisted dry reforming of methane (DRM) is considered as a potential way to convert natural gas into fuels and chemicals under near ambient temperature and pressure; particularly for distributed processes based on renewable energy. Both catalytic and photocatalytic technologies have been applied for DRM to investigate the CH4 conversion and the energy efficiency of the process. For conventional catalysis; metaldoped Ni-based catalysts are proposed as a leading vector for further development. However; coke deposition leads to fast deactivation of catalysts which limits the catalyst lifetime. Photocatalysis in combination with non-thermal plasma (NTP), on the other hand; is an enabling technology to convert CH4 to more reactive intermediates. Placing the catalyst directly in the plasma zone or using post-plasma photocatalysis could generate a synergistic effect to increase the formation of the desired products. In this review; the recent progress in the area of NTP-(photo)catalysis applications for DRM has been described; with an in-depth discussion of novel plasma reactor types and operational conditions including employment of ferroelectric materials and nanosecond-pulse discharges. Finally, recent developments in the area of optical diagnostic tools for NTP, such as optical emission spectroscopy (OES), in-situ FTIR, and tunable diode laser absorption spectroscopy (TDLAS), are reviewed.

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46

Lee, Jong-Heon, Seongbin Jo, Tae-Young Kim, Jin-Hyeok Woo, Yeji Lee, Min-Seok Kim, Hye-Ok Park, Soo-Chool Lee, and Jae-Chang Kim. "Preparation of Eggshell-Type Ru/Al2O3 Catalysts for Hydrogen Production Using Steam-Methane Reforming on PEMFC." Catalysts 11, no. 8 (August 9, 2021): 951. http://dx.doi.org/10.3390/catal11080951.

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Ru-based eggshell-type catalysts, in which Ru is located at the outer region of the pellet, were prepared by the impregnation method, using spherically shaped γ-Al2O3 pellets for steam-methane reforming (SMR). Ru was only supported on the external region of the pellet because of the strong interaction between its precursor and the alumina pellet. The Ru precursor penetrated the inside of the pellet by adding nitric acid to the impregnation solution. The distribution and thickness of the Ru layer in the catalyst can be controlled using the HNO3/Ru molar ratio and contact time at the impregnation step. Among the catalysts, the graded eggshell-type catalyst showed the highest activity and long-term stability in the SMR reaction. In addition, in the daily startup and shutdown (DSS) operation, similar to the hydrogen production environment for domestic polymer electrolyte membrane fuel cells (PEMFC), the graded eggshell-type catalyst showed high activity and stability after multiple cycles. Based on the experimental studies, it was confirmed that Ru-based catalysts are suitable for steam-methane reforming for PEMFC.

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47

Araújo, L. C. B. de, D. M. de A. Melo, M. A. de F. Melo, J. M. de F. Barros, R. M. Braga, C. de C. Costa, and G. Rodrigues. "Nickel catalyst supported on magnesium and zinc aluminates (MgAl2O4 and ZnAl2O4) spinels for dry reforming of methane." Cerâmica 63, no. 365 (March 2017): 77–81. http://dx.doi.org/10.1590/0366-69132017633652056.

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Abstract Materials such as MgAl2O4 and ZnAl2O4 assessed in the reaction of dry reforming of methane to produce syngas were synthesized by microwave-assisted combustion method using urea as fuel. Samples of synthesized oxides were calcined at 800 °C for 2 h and impregnated with 5% nickel. The impregnated samples were calcined at 850 °C for 4 h to obtain the desired phases. The results of the catalytic tests showed that the catalysts are active for the reaction of dry reforming of methane, and the catalyst that showed the best performance for methane conversion was 5% Ni/MgAl2O4 calcined at 850 °C/4 h.

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48

Wei, Ning, Jia Zhang, Hexiang Zhong, Liwei Pan, Zeyu Wang, Juan Wang, and Yi Zhou. "Methane Steam Reforming Over NiO/CexZryO2-Sil-1 Catalyst Prepared by In-Situ Self-Assembly." Journal of Nanoscience and Nanotechnology 19, no. 11 (November 1, 2019): 7416–20. http://dx.doi.org/10.1166/jnn.2019.16620.

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NiO/CexZryO2-Sil-1 catalysts were prepared using an In-Situ self-assembly approach by coupling silicalite-1 and CexZryO2. This one-step synthesis method utilized the high surface area and hydrothermal stability of silicalite-1 and the good oxidation-reduction ability of the CexZryO2, and hence offered high synthesis efficiency. The catalyst structure was examined by N2-physisorption, temperature-programmed reduction, transmission electron microscopy, and X-ray diffraction. All the results showed that silicalite-1 was well-encapsulated by NiO/Ce0.5Zr0.5O2. Furthermore, the effect of the Ce/Zr molar ratio on the performance of the catalysts was investigated in detail. The catalysts were subjected to methane steam reforming at high temperatures to evaluate their catalytic performance. The result showed that the NiO/Ce0.5Zr0.5O2-Sil-1 catalyst exhibited the best performance and its methane conversion efficiency reached up to 99.5%. Even after 16 h of continuous stability test, this catalyst could retain a methane conversion efficiency of 97.8%.

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49

Rusdan, Nisa Afiqah, Sharifah Najiha Timmiati, Wan Nor Roslam Wan Isahak, Zahira Yaakob, Kean Long Lim, and Dalilah Khaidar. "Recent Application of Core-Shell Nanostructured Catalysts for CO2 Thermocatalytic Conversion Processes." Nanomaterials 12, no. 21 (November 2, 2022): 3877. http://dx.doi.org/10.3390/nano12213877.

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Carbon-intensive industries must deem carbon capture, utilization, and storage initiatives to mitigate rising CO2 concentration by 2050. A 45% national reduction in CO2 emissions has been projected by government to realize net zero carbon in 2030. CO2 utilization is the prominent solution to curb not only CO2 but other greenhouse gases, such as methane, on a large scale. For decades, thermocatalytic CO2 conversions into clean fuels and specialty chemicals through catalytic CO2 hydrogenation and CO2 reforming using green hydrogen and pure methane sources have been under scrutiny. However, these processes are still immature for industrial applications because of their thermodynamic and kinetic limitations caused by rapid catalyst deactivation due to fouling, sintering, and poisoning under harsh conditions. Therefore, a key research focus on thermocatalytic CO2 conversion is to develop high-performance and selective catalysts even at low temperatures while suppressing side reactions. Conventional catalysts suffer from a lack of precise structural control, which is detrimental toward selectivity, activity, and stability. Core-shell is a recently emerged nanomaterial that offers confinement effect to preserve multiple functionalities from sintering in CO2 conversions. Substantial progress has been achieved to implement core-shell in direct or indirect thermocatalytic CO2 reactions, such as methanation, methanol synthesis, Fischer–Tropsch synthesis, and dry reforming methane. However, cost-effective and simple synthesis methods and feasible mechanisms on core-shell catalysts remain to be developed. This review provides insights into recent works on core-shell catalysts for thermocatalytic CO2 conversion into syngas and fuels

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50

Mundhwa, Mayur, and Christopher P. Thurgood. "Improved performance of a catalytic plate reactor coated with distributed layers of reforming and combustion catalysts for hydrogen production." Reaction Chemistry & Engineering 3, no. 4 (2018): 487–514. http://dx.doi.org/10.1039/c8re00013a.

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