Reforming of liquid hydrocarbon fuels for fuel cell applications PDF Download

Author: Dushyant Shekhawat
Publisher:
ISBN:
Category :
Languages : en
Pages : 111

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Author: Dushyant Shekhawat
Publisher: Elsevier
ISBN: 0444535640
Category : Technology & Engineering
Languages : en
Pages : 569

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Book Description
Fuel Cells: Technologies for Fuel Processing provides an overview of the most important aspects of fuel reforming to the generally interested reader, researcher, technologist, teacher, student, or engineer. The topics covered include all aspects of fuel reforming: fundamental chemistry, different modes of reforming, catalysts, catalyst deactivation, fuel desulfurization, reaction engineering, novel reforming concepts, thermodynamics, heat and mass transfer issues, system design, and recent research and development. While no attempt is made to describe the fuel cell itself, there is sufficient description of the fuel cell to show how it affects the fuel reformer. By focusing on the fundamentals, this book aims to be a source of information now and in the future. By avoiding time-sensitive information/analysis (e.g., economics) it serves as a single source of information for scientists and engineers in fuel processing technology. The material is presented in such a way that this book will serve as a reference for graduate level courses, fuel cell developers, and fuel cell researchers. Chapters written by experts in each area Extensive bibliography supporting each chapter Detailed index Up-to-date diagrams and full colour illustrations

Author: Terry Grice DuBois
Publisher:
ISBN:
Category : Fuel
Languages : en
Pages : 343

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The effect of oxygen-enriched catalytic reforming of heavy liquid hydrocarbon fuels has been theoretically and experimentally investigated. The objective of this research is to analyze the reactions, reaction products, and reformer and system level effects from oxygen enriched reforming of heavy hydrocarbon fuels (JP-8). To achieve the objective of this dissertation analytical modeling was employed to develop a theoretical basis for experimental work; a research grade experimental apparatus was designed, constructed, and tested; via experimentation, a JP-8 surrogate fuel was developed; and autothermal reformer performance was characterized with air and enriched oxygen under various operating scenarios. Notable contributions of this work were: good carbon conversion (~100%) and hydrogen yield can be achieved in autothermal reforming of heavy liquid hydrocarbon fuels; the development of a JP-8 surrogate fuel through experimental evaluation of the major hydrocarbon chemical classes present in JP-8: n-paraffin, cyclo-paraffin and mono-aromatics; a detailed study of the influence of each chemical class was evaluated under broad operating conditions and the contribution of each along with synergistic effects in mixtures was studied and contrasted with a target JP-8 fuel; oxygen enriched reforming of the surrogate fuel under varying oxygen concentration, fuel flows, and oxygen-to-carbon ratios was experimentally evaluated; and the influence of oxygen enriched reforming on the fuel cell system was analyzed. Oxygen enrichment is shown to allow for independent control of both reactor space time and the oxygen-to-carbon ratio during autothermal reforming. This allows for much better control over the reformer and allows for significant gains in reformer through-put without negative impacts to reformer performance. Additionally, the use of oxygen enriched reforming is shown to result in enhanced reformer performance and also enhanced fuel cell stack performance due to greatly increased hydrogen concentration in the reformate.

Author: Qusay Yousef Bkour
Publisher:
ISBN:
Category : Catalytic reforming
Languages : en
Pages : 367

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Book Description
The reforming of logistic liquid fuels for fuel cell applications is a challenging proposition because of the severe carbon deposition on the surface of the reforming catalyst and sulfur problems. It becomes more challenging for a catalyst to be able to reform fuels within realistic operation conditions that are compatible with fuel cells and tolerate the influence of various aromatic and poison compounds present in these fuels. Therefore, the successful reforming of these hydrocarbons will largely depend on the development of a catalyst. Supported nickel (Ni) catalyst and molybdenum carbide (Mo2C) have attracted considerable attention because of their unique chemical and physical properties and their affordable prices. However, coking over Ni catalyst and oxidation of Mo2C catalyst are the main challenges of these two catalysts. Coke formation often leads to the rapid deactivation of Ni-based catalysts and Mo2C catalysts cannot guarantee sufficient long-term stability under liquid fuel reforming conditions due to their phase instability. This work aims to improve the coking resistance of Ni catalyst by introducing a low contraction of Mo, and improve the phase stability and the performance of Mo2C by introducing of Ni and Ti.The Ni-Mo catalyst showed high reforming activity and stability with isooctane (gasoline surrogate) conversion of 97% and H2 yield of 73% over 24 hours. Our results indicated that less degree of sintering took place for the sample with Mo. Ni-Mo catalyst was used as an internal micro-reforming layer on top of conventional Ni-YSZ anode supported single cells. By applying the Ni-Mo/YSZ catalytic internal reforming layer, the single-cell displayed significantly improved stability with a low degradation rate compared to the cell without the catalyst layer. Ni-Mo2C and Ti-Mo2C catalysts exhibited excellent stability over the 24 h test period without indication of oxidation or coking with carbon conversion of 90%, H2 yield of 56% and CO yield of 63%. The addition of Ti or Ni to Mo2C improves hydrocarbon activation, which enhances the carburization process of the carbide catalysts. Thus, the balance between the oxidation of Mo2C and carburization of MoOx can be achieve.

Author: W. R. Alcorn
Publisher:
ISBN:
Category :
Languages : en
Pages : 73

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Theoretical and experimental studies of the integrated anode in the internal-reforming hydrocarbon-air fuel cell were conducted. Catalyst activity, reaction kinetics and mass transfer effects were evaluated with two experimental systems: a one-inch anode cell and a packed-bed reactor. A computer program was prepared to determine equilibrium gas compositions obtained in hydrocarbon reforming. 1.5 and 1.0-mil Pd/Ag membranes were activated on the gas-side with various combinations of deposited metals to determine their reforming capacity and hydrogen extraction efficiency at low pressures. Reforming capacity was very low. On the basis of limited data, hydrogen extraction efficiency appears to be somewhat improved by certain combinations of Pd, Ni, and Co. Reactor studies indicated that significant delay of catalyst reforming activity is probably associated with deposition of carbon, in some form, during reforming. Little or no effect of sulfur compounds on activity was observed. (Author).

Author: James R. Lattner
Publisher:
ISBN:
Category : Chemical engineering
Languages : en
Pages :

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Author: Ke Liu
Publisher: John Wiley & Sons
ISBN: 0471719757
Category : Technology & Engineering
Languages : en
Pages : 572

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Book Description
Covers the timely topic of fuel cells and hydrogen-based energy from its fundamentals to practical applications Serves as a resource for practicing researchers and as a text in graduate-level programs Tackles crucial aspects in light of the new directions in the energy industry, in particular how to integrate fuel processing into contemporary systems like nuclear and gas power plants Includes homework-style problems

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 11

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At Argonne National Laboratory we are developing a process to convert hydrocarbon fuels to a clean hydrogen feed for a fuel cell. The process incorporates a partial oxidation/steam reforming catalyst that can process hydrocarbon feeds at lower temperatures than existing commercial catalysts. We have tested the catalyst with three diesel-type fuels: hexadecane, low-sulfur diesel fuel, and a regular diesel fuel. We achieved complete conversion of the feed to products. Hexadecane yielded products containing 60% hydrogen on a dry, nitrogen-free basis at 800 C. For the two diesel fuels, higher temperatures,>850 C, were required to approach similar levels of hydrogen in the product stream. At 800 C, hydrogen yield of the low sulfur diesel was 32%, while that of the regular diesel was 52%. Residual products in both cases included CO, CO2, ethane, ethylene, and methane.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

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Fuel cell development has seen remarkable progress in the past decade because of an increasing need to improve energy efficiency as well as to address concerns about the environmental consequences of using fossil fuel for producing electricity and for propulsion of vehicles [1]. The lack of an infrastructure for producing and distributing H2 has led to a research effort to develop on-board fuel processing technology for reforming hydrocarbon fuels to generate H2 [2]. The primary focus is on reforming gasoline, because a production and distribution infrastructure for gasoline already exists to supply internal combustion engines [3]. Existing reforming technology for the production of H2 from hydrocarbon feedstocks used in large-scale manufacturing processes, such as ammonia synthesis, is cost prohibitive when scaled down to the size of the fuel processor required for transportation applications (50-80 kWe) nor is it designed to meet the varying power demands and frequent shutoffs and restarts that will be experienced during normal drive cycles. To meet the performance targets required of a fuel processor for transportation applications will require new reforming reactor technology developed to meet the volume, weight, cost, and operational characteristics for transportation applications and the development of new reforming catalysts that exhibit a higher activity and better thermal and mechanical stability than reforming catalysts currently used in the production of H2 for large-scale manufacturing processes.

Author: Andrew L. Dicks
Publisher: John Wiley & Sons
ISBN: 1118706978
Category : Technology & Engineering
Languages : en
Pages : 488

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Book Description
Since publication of the first edition of Fuel Cell Systems Explained, three compelling drivers have supported the continuing development of fuel cell technology. These are: the need to maintain energy security in an energy-hungry world, the desire to move towards zero-emission vehicles and power plants, and the mitigation of climate change by lowering of CO2 emissions. New fuel cell materials, enhanced stack performance and increased lifetimes are leading to the emergence of the first truly commercial systems in applications that range from fork-lift trucks to power sources for mobile phone towers. Leading vehicle manufacturers have embraced the use of electric drive-trains and now see hydrogen fuel cells complementing advanced battery technology in zero-emission vehicles. After many decades of laboratory development, a global but fragile fuel cell industry is bringing the first commercial products to market. This thoroughly revised edition includes several new sections devoted to, for example, fuel cell characterisation, improved materials for low-temperature hydrogen and liquid-fuelled systems, and real-world technology implementation. Assuming no prior knowledge of fuel cell technology, the third edition comprehensively brings together all of the key topics encompassed in this diverse field. Practitioners, researchers and students in electrical, power, chemical and automotive engineering will continue to benefit from this essential guide to the principles, design and implementation of fuel cell systems.