The Experts below are selected from a list of 5580 Experts worldwide ranked by ideXlab platform
J A Menendez - One of the best experts on this subject based on the ideXlab platform.
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Dry Reforming of coke oven gases over activated carbon to produce syngas for methanol synthesis
Fuel, 2010Co-Authors: J M Bermudez, Beatriz Fidalgo, A Arenillas, J A MenendezAbstract:The Dry Reforming of coke oven gases (COG) over an activated carbon used as catalyst has been studied in order to produce a syngas suitable for methanol synthesis. The primary aim of this work was to study the influence of the high amount of hydrogen present in the COG on the process of Dry Reforming, as well as the influence of other operation conditions, such us temperature and volumetric hourly space velocity (VHSV). It was found that the reverse water gas shift (RWGS) reaction takes place due to the hydrogen present in the COG, and that its influence on the process increases as the temperature decreases. This situation may give rise to the consumption of the hydrogen present in the COG, and the consequent formation of a syngas which is inappropriate for the synthesis of methanol. This reaction can be avoided by working at high temperatures (about 1000 °C) in order to produce a syngas that is suitable for methanol synthesis. It was also found that the RWGS reaction is favoured by an increase in the VHSV. In addition, the active carbon FY5 was proven to be an adequate catalyst for the production of syngas from COG.
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comparative study of conventional and microwave assisted pyrolysis steam and Dry Reforming of glycerol for syngas production using a carbonaceous catalyst
Journal of Analytical and Applied Pyrolysis, 2010Co-Authors: Y Fernandez, A Arenillas, J M Bermudez, J A MenendezAbstract:The thermal valorization of glycerol to produce synthesis gas has been investigated under conventional and microwave heating systems. Different processes (pyrolysis, steam Reforming and Dry Reforming) are compared, using a commercial activated carbon as catalyst. The Reforming processes that employ oxidizing agents (CO2 or H2O) were found to promote higher glycerol conversions than mere thermal decomposition. Steam Reforming generates the lowest gas fraction and the highest amounts of hydrogen and syngas, while the opposite occurs in the Dry Reforming experiments. Microwave processing produced higher gas yields with large syngas content than conventional heating processes in all cases. The use of carbon-based catalysts appears to be highly suitable for producing synthesis gas with a H2/CO ratio close to 1, minimum CO2 emissions being an additional advantage.
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microwave assisted Dry Reforming of methane
International Journal of Hydrogen Energy, 2008Co-Authors: Beatriz Fidalgo, A Dominguez, J J Pis, J A MenendezAbstract:Abstract The microwave-assisted Dry Reforming of methane over an activated carbon, which acted as catalyst and microwave receptor, was investigated. As a preliminary study, the CO2 Reforming of CH4 was carried out using conventional heating and microwave heating in order to compare both heating devices. Higher conversions of CH4 and CO2 were achieved by microwave heating. Under microwave heating, various operating variables were studied in order to determine the best conditions for performing Dry Reforming with high conversions and the most suitable H2/CO ratio. Thus, the Dry Reforming reaction was studied at different temperatures. An optimum range of working temperatures (between 700 °C and 800 °C) was established. In this range of temperatures, the Dry Reforming reaction is believed to take place as a combination of CH4 decomposition and CO2 gasification. Carbonaceous deposits from CH4 decomposition are gasified by CO2 and, as a result, active centres for the Dry Reforming reaction are constantly regenerated. The effect of the proportion of CO2 fed in on the CH4 and CO2 conversions was also investigated. Small increases in the percentage of CO2 fed in gave rise to large increases in both conversions, but especially in the case of CH4. The volumetric hourly space velocity was also studied. It was found that the lower the space velocity, the higher the conversions obtained.
Fagen Wang - One of the best experts on this subject based on the ideXlab platform.
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performance enhancement of methane Dry Reforming reaction for syngas production over ir ce0 9la0 1o2 nanorods catalysts
Catalysis Today, 2019Co-Authors: Fagen Wang, Linjia Zhang, Leilei Xu, Zhongcheng Li, Hao Yu, Zhiyong DengAbstract:Abstract Ir catalysts supported on Ce0.9La0.1O2 nanorods and nanoparticles were comparatively investigated for syngas production from methane Dry Reforming reaction. The exposure of active {110} and {100} crystal planes in the Ir/Ce0.9La0.1O2- nanorods catalysts contributed to the stronger redox property and more oxygen vacancy than those in the Ir/Ce0.9La0.1O2-nanoparticles catalysts. These advantages facilitated activation and transformation of methane and carbon dioxide, giving an enhanced performance of methane Dry Reforming reaction over the Ir/Ce0.9La0.1O2-nanorods catalysts. The work demonstrated significant influences of support morphologies in obtaining stable catalysts for methane Dry Reforming reaction.
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thermally stable ir ce0 9la0 1o2 catalyst for high temperature methane Dry Reforming reaction
Nano Research, 2017Co-Authors: Fagen Wang, Leilei Xu, Jian Zhang, Kai Wu, Yu Zhao, Hui Li, He Xing Li, Guo Qin Xu, Wei ChenAbstract:In this study, the use of a thermally stable Ir/Ce0.9La0.1O2 catalyst was investigated for the Dry Reforming of methane. The doping of La2O3 into the CeO2 lattice enhanced the chemical and physical properties of the Ir/Ce0.9La0.1O2 catalyst, such as redox properties, Ir dispersion, oxygen storage capacity, and thermal stability, with respect to the Ir/CeO2 catalyst. Hence, the Ir/Ce0.9La0.1O2 catalyst exhibits higher activity and stabler performance for the Dry Reforming of methane than the Ir/CeO2 catalyst. This observation can be mainly attributed to the stronger interaction between the metal and support in the Ir/Ce0.9La0.1O2 catalyst stabilizing the catalyst structure and improving the oxygen storage capacity, leading to negligible aggregation of Ir nanoparticles and the Ce0.9La0.1O2 support at high temperatures, as well as the rapid removal of carbon deposits at the boundaries between the Ir metal and the Ce0.9La0.1O2 support.
Genira Carneiro De Araujo - One of the best experts on this subject based on the ideXlab platform.
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catalytic evaluation of perovskite type oxide lani1 xruxo3 in methane Dry Reforming
Catalysis Today, 2008Co-Authors: Genira Carneiro De Araujo, Sania M De Lima, Jose Mansur Assaf, M A Pena, J L G Fierro, Maria Do Carmo RangelAbstract:The methane Reforming with carbon dioxide (Dry Reforming) has been proposed as one of the most promising technologies for producing hydrogen by the use of two greenhouse gases. However, undesirable coke formation is the crucial issue to develop efficient catalysts for the reaction. In order to find alternative catalysts, which can be more resistant against coke deactivation, perovskite-type oxides LaRu x Ni 1-x O 3 (0.0 < x < 1.0) were studied in this work. Samples were prepared by thermal decomposition of amorphous citrate precursors followed by heating at 800 or 1000 °C, for 12 h, in air. The solids were characterized by X-ray diffraction, temperature-programmed reduction, temperature-programmed desorption, specific surface area measurements and X-ray photoelectron spectroscopy. The catalysts were reduced under hydrogen and tested in methane Dry Reforming at 1 atm and 750 °C. The coke produced was characterized by thermogravimetry, carbon measurement and scanning and transmission electron microscopy. The oxide precursors showed low specific surface areas and different reducing behavior. All catalysts were active in the reaction. They all produced filamentous coke but it was not harmful to the catalysts. Nickel is more active and selective to hydrogen than ruthenium but the later improved the stability of the catalysts decreasing coke formation. The most promising catalyst was the LaNi 0.8 Ru 0.2 O 3 sample, which was the most resistant against coke deposition.
Jianguo Jiang - One of the best experts on this subject based on the ideXlab platform.
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A review of recent developments in hydrogen production via biogas Dry Reforming
Energy Conversion and Management, 2018Co-Authors: Yuchen Gao, Yuan Meng, Jianguo Jiang, Feng Yan, Aikelaimu AihemaitiAbstract:Biogas is a promising renewable energy resource. Among the existing biogas utilization technologies, Dry Reforming can convert two major greenhouse gases in biogas, methane and carbon dioxide, into syngas. In this review, we summarize the recent advances in biogas Dry Reforming toward hydrogen production, including the preparation of catalysts, the optimization of operation conditions, and the influence of impurities in biogas. The development of bimetallic catalysts and core-shell structure catalysts has become increasingly attractive due to their high catalytic activity and stability. Choosing active metals, supports, and promoters for catalysts is systematically discussed, and different catalyst synthesis methods are compared. Solid waste-derived catalysts have been developed as a new approach to obtain a high added value of solid waste and reduce the costs of catalyst preparation. The influences of reaction temperature, pressure, calcination conditions, reduction conditions, and gas hourly space velocity on Dry Reforming reactions are discussed in detail. In addition to conventional fixed bed and fluidized bed reactors, several newer reactors are introduced, including membrane reactors, microreactors, and solar thermal flow reactors. Impurities in biogas such as hydrogen sulfide, oxygen, and siloxanes have significant effects on Dry Reforming. These effects are summarized to improve overall understanding of biogas Dry Reforming and to provide guidelines for its industrial application in hydrogen energy generation.
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Dry Reforming of model biogas on a ni sio2 catalyst overall performance and mechanisms of sulfur poisoning and regeneration
ACS Sustainable Chemistry & Engineering, 2017Co-Authors: Yuchen Gao, Jianguo Jiang, Feng Yan, Xuejing Chen, Sicong Tian, Hui ZhouAbstract:Carbon-neutral application of renewable biogas to valuable chemical raw materials has received much attention in sustainable areas, while sulfur poisoning remains a big problem in biogas Dry Reforming process. In this work, sulfur deactivation and regeneration performance of a Ni/SiO2 catalyst in model biogas Dry Reforming and related mechanisms were studied. The effects of H2S content (50 and 100 ppm) and reaction temperature (700–800 °C) on biogas Dry Reforming were investigated. Three regeneration methods (H2S feeding cessation, temperature-programmed calcination (TPC), and O2 activation) were applied. The results showed that the presence of H2S caused server deactivation in catalytic activity, and higher H2S content led to faster deactivation. The deactivation was not reversed simply by stopping H2S feeding and TPC, but O2 activation could totally recover deactivated catalysts. The formation of Ni7S6, detected for the first time in biogas conditioning catalytic processes, confirmed by X-ray diffractio...
Yuchen Gao - One of the best experts on this subject based on the ideXlab platform.
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A review of recent developments in hydrogen production via biogas Dry Reforming
Energy Conversion and Management, 2018Co-Authors: Yuchen Gao, Yuan Meng, Jianguo Jiang, Feng Yan, Aikelaimu AihemaitiAbstract:Biogas is a promising renewable energy resource. Among the existing biogas utilization technologies, Dry Reforming can convert two major greenhouse gases in biogas, methane and carbon dioxide, into syngas. In this review, we summarize the recent advances in biogas Dry Reforming toward hydrogen production, including the preparation of catalysts, the optimization of operation conditions, and the influence of impurities in biogas. The development of bimetallic catalysts and core-shell structure catalysts has become increasingly attractive due to their high catalytic activity and stability. Choosing active metals, supports, and promoters for catalysts is systematically discussed, and different catalyst synthesis methods are compared. Solid waste-derived catalysts have been developed as a new approach to obtain a high added value of solid waste and reduce the costs of catalyst preparation. The influences of reaction temperature, pressure, calcination conditions, reduction conditions, and gas hourly space velocity on Dry Reforming reactions are discussed in detail. In addition to conventional fixed bed and fluidized bed reactors, several newer reactors are introduced, including membrane reactors, microreactors, and solar thermal flow reactors. Impurities in biogas such as hydrogen sulfide, oxygen, and siloxanes have significant effects on Dry Reforming. These effects are summarized to improve overall understanding of biogas Dry Reforming and to provide guidelines for its industrial application in hydrogen energy generation.
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Dry Reforming of model biogas on a ni sio2 catalyst overall performance and mechanisms of sulfur poisoning and regeneration
ACS Sustainable Chemistry & Engineering, 2017Co-Authors: Yuchen Gao, Jianguo Jiang, Feng Yan, Xuejing Chen, Sicong Tian, Hui ZhouAbstract:Carbon-neutral application of renewable biogas to valuable chemical raw materials has received much attention in sustainable areas, while sulfur poisoning remains a big problem in biogas Dry Reforming process. In this work, sulfur deactivation and regeneration performance of a Ni/SiO2 catalyst in model biogas Dry Reforming and related mechanisms were studied. The effects of H2S content (50 and 100 ppm) and reaction temperature (700–800 °C) on biogas Dry Reforming were investigated. Three regeneration methods (H2S feeding cessation, temperature-programmed calcination (TPC), and O2 activation) were applied. The results showed that the presence of H2S caused server deactivation in catalytic activity, and higher H2S content led to faster deactivation. The deactivation was not reversed simply by stopping H2S feeding and TPC, but O2 activation could totally recover deactivated catalysts. The formation of Ni7S6, detected for the first time in biogas conditioning catalytic processes, confirmed by X-ray diffractio...
