Chemical Looping Materials for CO2 Driven Oxidation of Methane PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Chemical Looping Materials for CO2 Driven Oxidation of Methane PDF full book. Access full book title Chemical Looping Materials for CO2 Driven Oxidation of Methane by Michelle Smithenry. Download full books in PDF and EPUB format.
Author: Michelle Smithenry
Publisher:
ISBN:
Category : Carbon dioxide
Languages : en
Pages : 112
Get Book Here
Book Description
In this work the performance of cerium-based oxygen carriers is investigated in a simulated chemical looping dry reforming system using methane and carbon dioxide as fuel and oxidizing gas respectively. The samples to be studied are pure cerium oxide and cerium oxide doped with zirconium, yttrium, samarium, and scandium more specifically: CeO2, Ce0.8Y0.2O1.9, Ce0.85Y0.05Zr0.1O1.975, Ce0.95Zr0.05O2, Ce0.9Sm0.05Zr0.05O1.975, and Ce0.9Sc0.05Zr0.05O1.975. Characteristics such as crystallography including lattice parameter and particle size of the samples are evaluated using X-ray diffraction (XRD) and particle size analysis. The oxygen transport capacity will also be measured using a thermogravimetric analyzer (TGA). This method of measurement also allowed for insight on oxygen release temperatures as well as recyclability of the samples. The particle size analysis showed that the synthesis method of precipitation-agglomeration resulted in samples with consistent particle size distribution indicating the method can be scaled up. The X-ray analysis of samples before and after the TGA tests show that all the materials tested had a cubic fluorite crystal structure which was maintained through the oxidation reduction cycles. The lattice parameter was found to increase slightly with a loss in oxygen content in the samples. The addition of trivalent dopants resulted in a decrease in the temperature of initiation of reduction in methane. While reduction of commercial ceria initiated near 800 oC. the addition of trivalent dopants resulted in a lowering of the initialization temperature between of 150 - 200oC. The activation energy of commercial ceria was 248.42 kJ/mol for reduction in methane, indicating that the rate controlling mechanism is chemical reaction rather than diffusion. The addition of trivalent dopants resulted in a significant lowering in the activation energy. The activation energies obtained in this study show that the addition of dopant increased the significance of diffusion through the solid and the controlling mechanisms were both diffusion and chemical reaction. Overall, the addition of trivalent dopants enhanced the extent of oxygen exchange in CLDR process.
Author: Michelle Smithenry
Publisher:
ISBN:
Category : Carbon dioxide
Languages : en
Pages : 112
Get Book Here
Book Description
In this work the performance of cerium-based oxygen carriers is investigated in a simulated chemical looping dry reforming system using methane and carbon dioxide as fuel and oxidizing gas respectively. The samples to be studied are pure cerium oxide and cerium oxide doped with zirconium, yttrium, samarium, and scandium more specifically: CeO2, Ce0.8Y0.2O1.9, Ce0.85Y0.05Zr0.1O1.975, Ce0.95Zr0.05O2, Ce0.9Sm0.05Zr0.05O1.975, and Ce0.9Sc0.05Zr0.05O1.975. Characteristics such as crystallography including lattice parameter and particle size of the samples are evaluated using X-ray diffraction (XRD) and particle size analysis. The oxygen transport capacity will also be measured using a thermogravimetric analyzer (TGA). This method of measurement also allowed for insight on oxygen release temperatures as well as recyclability of the samples. The particle size analysis showed that the synthesis method of precipitation-agglomeration resulted in samples with consistent particle size distribution indicating the method can be scaled up. The X-ray analysis of samples before and after the TGA tests show that all the materials tested had a cubic fluorite crystal structure which was maintained through the oxidation reduction cycles. The lattice parameter was found to increase slightly with a loss in oxygen content in the samples. The addition of trivalent dopants resulted in a decrease in the temperature of initiation of reduction in methane. While reduction of commercial ceria initiated near 800 oC. the addition of trivalent dopants resulted in a lowering of the initialization temperature between of 150 - 200oC. The activation energy of commercial ceria was 248.42 kJ/mol for reduction in methane, indicating that the rate controlling mechanism is chemical reaction rather than diffusion. The addition of trivalent dopants resulted in a significant lowering in the activation energy. The activation energies obtained in this study show that the addition of dopant increased the significance of diffusion through the solid and the controlling mechanisms were both diffusion and chemical reaction. Overall, the addition of trivalent dopants enhanced the extent of oxygen exchange in CLDR process.
Author: Paul Fennell
Publisher: Elsevier
ISBN: 0857097601
Category : Technology & Engineering
Languages : en
Pages : 467
Get Book Here
Book Description
Calcium and Chemical Looping Technology for Power Generation and Carbon Dioxide (CO2) Capture reviews the fundamental principles, systems, oxygen carriers, and carbon dioxide carriers relevant to chemical looping and combustion. Chapters review the market development, economics, and deployment of these systems, also providing detailed information on the variety of materials and processes that will help to shape the future of CO2 capture ready power plants. - Reviews the fundamental principles, systems, oxygen carriers, and carbon dioxide carriers relevant to calcium and chemical looping - Provides a lucid explanation of advanced concepts and developments in calcium and chemical looping, high pressure systems, and alternative CO2 carriers - Presents information on the market development, economics, and deployment of these systems
Author: Ronald W. Breault
Publisher: John Wiley & Sons
ISBN: 3527342028
Category : Business & Economics
Languages : en
Pages : 488
Get Book Here
Book Description
This comprehensive and up-to-date handbook on this highly topical field, covering everything from new process concepts to commercial applications. Describing novel developments as well as established methods, the authors start with the evaluation of different oxygen carriers and subsequently illuminate various technological concepts for the energy conversion process. They then go on to discuss the potential for commercial applications in gaseous, coal, and fuel combustion processes in industry. The result is an invaluable source for every scientist in the field, from inorganic chemists in academia to chemical engineers in industry.
Author: Elena Yin-Yin Chung
Publisher:
ISBN:
Category :
Languages : en
Pages : 154
Get Book Here
Book Description
In order to overcome these process limitations, the chemical looping technology platform presents an attractive opportunity to convert hydrocarbons to flexible products utilizing intermediate oxygen carriers rather than gaseous co-fed oxidants. This study compares the traditional co-feed approach to the chemical looping approach for selectively controlling both the OCM and selective n-butane oxidation reactions with a focus on overcoming the technical issues that prevented these processes from achieving commercial application. These experimental results are used in process simulations in order to model and compare the theoretical commercial co-feed system with the commercial chemical looping system. For example, previous work demonstrated that pressure and steam have an effect on methane conversion and C2+ selectivity with the OCM co-feed and chemical looping processes. Initial simulations demonstrate that with proper heat integration, the OCM chemical looping process exhibits promising reactor and process operations for an alternative direct approach to utilize methane. The processes demonstrate that the application of chemical looping can be used as a novel and efficient approach for the conversion of hydrocarbons, especially alkanes, to electricity with CO2 capture, syngas and chemicals. With the emerging challenge of climate change and the continued escalation of energy demands, innovative and flexible fuel conversion technologies are necessary and gaining recognition. Chemical looping technologies have the potential to not only reduce energy costs, but also to mitigate carbon emissions. Historically, the general concept of this reduction-oxidation mechanism has been suggested, but the process was never commercialized. Recent interests in carbon capture techniques have revitalized the adaptive chemical looping system. Chemical looping technologies can utilize both gaseous and solid fuels such as natural gas and coal, respectively, for power, hydrogen or chemical generation. However, the success of technological adoption requires a thorough understanding of the types of chemical looping techniques, the design considerations, and the reactor modes of configurations.
Author: Liang-Shih Fan
Publisher: Cambridge University Press
ISBN: 1108160417
Category : Technology & Engineering
Languages : en
Pages : 497
Get Book Here
Book Description
This is the first comprehensive guide to the principles and techniques of chemical looping partial oxidation. With authoritative explanations from a pioneer of the chemical looping process, you will: • Gain a holistic overview of metal oxide reaction engineering, with coverage of ionic diffusion, nanostructure formation, morphological evolution, phase equilibrium, and recyclability properties of metal oxides during redox reactions • Learn about the gasification of solid fuels, the reforming of natural gas, and the catalytic conversion of methane to olefins • Understand the importance of reactor design and process integration in enabling metal oxide oxygen carriers to produce desired products • Discover other applications of catalytic metal oxides, including the production of maleic anhydride and solar energy conversions Aspen Plus® simulation software and results accompany the book online. This is an invaluable reference for researchers and industry professionals in the fields of chemical, energy and environmental engineering, and students studying process design and optimization.
Author: Liang-Shih Fan
Publisher: John Wiley & Sons
ISBN: 1118063139
Category : Technology & Engineering
Languages : en
Pages : 353
Get Book Here
Book Description
This book presents the current carbonaceous fuel conversion technologies based on chemical looping concepts in the context of traditional or conventional technologies. The key features of the chemical looping processes, their ability to generate a sequestration-ready CO2 stream, are thoroughly discussed. Chapter 2 is devoted entirely to the performance of particles in chemical looping technology and covers the subjects of solid particle design, synthesis, properties, and reactive characteristics. The looping processes can be applied for combustion and/or gasification of carbon-based material such as coal, natural gas, petroleum coke, and biomass directly or indirectly for steam, syngas, hydrogen, chemicals, electricity, and liquid fuels production. Details of the energy conversion efficiency and the economics of these looping processes for combustion and gasification applications in contrast to those of the conventional processes are given in Chapters 3, 4, and 5.Finally, Chapter 6 presents additional chemical looping applications that are potentially beneficial, including those for H2 storage and onboard H2 production, CO2 capture in combustion flue gas, power generation using fuel cell, steam-methane reforming, tar sand digestion, and chemicals and liquid fuel production. A CD is appended to this book that contains the chemical looping simulation files and the simulation results based on the ASPEN Plus software for such reactors as gasifier, reducer, oxidizer and combustor, and for such processes as conventional gasification processes, Syngas Chemical Looping Process, Calcium Looping Process, and Carbonation-Calcination Reaction (CCR) Process. Note: CD-ROM/DVD and other supplementary materials are not included as part of eBook file.
Author: Yan Liu
Publisher:
ISBN:
Category : Methane
Languages : en
Pages : 177
Get Book Here
Book Description
Natural gas, which is mainly composed of methane, is an important industrial resource for syngas production. Nevertheless, the conventional methane to syngas conversion processes are highly energy intensive and suffer from low methane conversion. Chemical looping partial oxidation of methane is a promising alternative technology that consists two reactors connected by an oxygen carrier particle loop. This process has high syngas selectivity with higher energy efficiency, minimal environmental impact, and proper H2 to CO ratio for downstream operations. The major challenge for chemical looping processes is the development of high-performance oxygen carriers with high reactivity, recyclability, and recyclability. Our group employed novel iron-based oxygen carrier mixed with metal oxide support. The particles show extraordinary recyclability that sustained over 3000 redox cycles at 1000 oC without reactivity or mechanical deteriorates. Despite research efforts have been put into oxygen carrier development, there are still scopes for syngas yield and purification improvement, especially at low temperatures. In this dissertation, nanoscaled oxygen carriers are explored as oxygen carrier for chemical looping partial oxidation process. Nanoparticles have higher surface area and smaller size compared to bulk material, therefore increasing reaction rate by enhancing the surface reactivity and ionic diffusion. Mesoporous support was utilized to disperse and stabilize the nanoscaled oxygen carrier. The confinement effect of the mesopores of the support can separate the nanoparticles and prevent their aggregation during the reaction. SBA-15 supported iron oxides nanoparticles shows near 100% syngas selectivity and sustained over 75 redox cycles at 800 oC. Density functional theory calculations also indicate that nanoparticles have higher methane conversion rate and syngas selectivity. The effect of the mesoporous support structure on the reactivity of the oxygen carrier is also studied by both experiments and Dynamic Monte-Carlo simulations. With 2-D hexagonal cylindrical structure, SBA-15 can trap gas molecules and decrease the gas diffusion rate in the mesopores. While 3-D interconnected mesoporous support SBA-16 can decrease the congestion and trapping effect, therefore nanoparticles supported on SBA-16 show increased reaction rate compared with those on SBA-15. Dopant modification was also applied to nanoparticles. Nevertheless, doped iron oxide nanoparticles do not show extraordinary improvement in reactivity, stability, or selectivity, since the reactivity of the nanoparticles are not limited by surface active sites or ionic diffusivity. With the growing energy and environmental demands, chemical looping processes are facing more opportunities and challenges in oxygen carrier development. The research in this dissertation enlightens the chemical looping technology in the near future.
Author: Yi Cheng
Publisher: John Wiley & Sons
ISBN: 1119251087
Category : Technology & Engineering
Languages : en
Pages : 1041
Get Book Here
Book Description
Provides a comprehensive review on the brand-new development of several multiphase reactor techniques applied in energy-related processes Explains the fundamentals of multiphase reactors as well as the sophisticated applications Helps the reader to understand the key problems and solutions of clean coal conversion techniques Details the emerging processes for novel refining technology, clean coal conversion techniques, low-cost hydrogen productions and CO2 capture and storage Introduces current energy-related processes and links the basic principles of emerging processes to the features of multiphase reactors providing an overview of energy conversion in combination with multiphase reactor engineering Includes case studies of novel reactors to illustrate the special features of these reactors
Author: Azadeh Amiri
Publisher:
ISBN:
Category : Carbon dioxide
Languages : en
Pages : 166
Get Book Here
Book Description
The focus of this work is to investigate the feasibility of oxygen extraction from CO2 by doped ceria in chemical looping process. In order to increase the oxygen capacity and oxygen release rates, Cerium- based oxygen carriers are doped with ZrO2. Additionally, the zirconia-doped ceria is modified by iron and copper to boost the oxygen release in the fuel reactor. It should be noted that the level of doping allows the solids to maintain the cubic fluorite structure of CeO2. The redox activity of oxygen carriers is studied in order to determine the most promising material due to the oxygen transfer capacity and methane conversion. The chemical looping dry reforming in a quartz fixed-bed reactor is carried out in two steps. In the first step, the oxygen carriers are reduced by methane through the combustion reaction. In the second step, CO2 is used for oxidation of reduced metal oxides. The obtained results at different doping levels were compared to determine the optimal oxygen carrier. The results indicate that doping ceria can boost the reactivity with methane and enhance the methane conversion during combustion reaction. CeO2 modified by Fe presents a progress in both oxygen release and uptake with an increase in oxygen capacity of metal oxide. However, zirconia and copper ceria show different effect on reduction and oxidation. This means that zirconia doped ceria results in an increase in oxygen release during reduction and decrease in oxygen uptake during oxidation with CO2. In contrast, addition of copper to ceria metal oxides shows a negative effect on oxygen release, while it enhances the ability of oxygen uptake. Out of all mixed cerium oxides investigated in this study, cerium oxide containing 10% mole iron is determined as the most promising oxygen carrier for CLDR due to the methane conversion, facilitating oxygen release, increasing the level of reduction and improving the oxidation uptake of the metal oxide in the reaction with CO2.
Author: Fabrizio Scala
Publisher: Elsevier
ISBN: 0857098802
Category : Technology & Engineering
Languages : en
Pages : 1091
Get Book Here
Book Description
Fluidized bed (FB) combustion and gasification are advanced techniques for fuel flexible, high efficiency and low emission conversion. Fuels are combusted or gasified as a fluidized bed suspended by jets with sorbents that remove harmful emissions such as SOx. CO2 capture can also be incorporated. Fluidized bed technologies for near-zero emission combustion and gasification provides an overview of established FB technologies while also detailing recent developments in the field.Part one, an introductory section, reviews fluidization science and FB technologies and includes chapters on particle characterization and behaviour, properties of stationary and circulating fluidized beds, heat and mass transfer and attrition in FB combustion and gasification systems. Part two expands on this introduction to explore the fundamentals of FB combustion and gasification including the conversion of solid, liquid and gaseous fuels, pollutant emission and reactor design and scale up. Part three highlights recent advances in a variety of FB combustion and gasification technologies before part four moves on to focus on emerging CO2 capture technologies. Finally, part five explores other applications of FB technology including (FB) petroleum refining and chemical production.Fluidized bed technologies for near-zero emission combustion and gasification is a technical resource for power plant operators, industrial engineers working with fluidized bed combustion and gasification systems and researchers, scientists and academics in the field. - Examines the fundamentals of fluidized bed (FB) technologies, including the conversion of solid, liquid and gaseous fuels - Explores recent advances in a variety of technologies such as pressurized FB combustion, and the measurement, monitoring and control of FB combustion and gasification - Discusses emerging technologies and examines applications of FB in other processes
