Investigation of Methanol Transport and Reaction Kinetics in Direct Methanol Fuel Cells 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 Investigation of Methanol Transport and Reaction Kinetics in Direct Methanol Fuel Cells PDF full book. Access full book title Investigation of Methanol Transport and Reaction Kinetics in Direct Methanol Fuel Cells by Srikanth Arisetty. Download full books in PDF and EPUB format.
Author: Srikanth Arisetty Publisher: ISBN: 9781124240503 Category : Fuel cells Languages : en Pages :
Book Description
Direct Methanol Fuel Cells (DMFCs) have been demonstrated extensively as electrical power sources for portable applications. In DMFCs, the chemical energy stored in methanol is converted directly to electrical energy through a number of chemical, transport and kinetic processes. The overall efficiency of the DMFC system can be improved by optimizing these processes with precise control over operating conditions. The goal of this research is to evaluate optimal operating conditions and system design for improving the DMFC's electrical performance through a combination of experimental strategies and process models. A DMFC system incorporating metal foams as the flow field was designed to increase system efficiency. The influence of metal foam parameters and operating conditions on fuel cell performance was investigated. Our results indicated that due to the opposing effects of methanol concentration on anode and cathode kinetics, there exists an optimal value of methanol concentration at each current density that will yield the highest electrical performance. A control algorithm employing feedback from the fuel cell voltage was implemented to dynamically adjust the methanol feed concentration for peak DMFC performance. Additionally, water and methanol crossover fluxes across the membrane were also measured to understand their transport rates under different conditions. The physico-chemical processes in DMFCs were investigated by developing an accurate mathematical model coupling mass transport with reaction kinetics within the five-layer membrane electrode assembly of the DMFC. An experimental scheme was developed to measure the overpotential contributions of anode methanol oxidation, cathode oxygen reduction and cathode methanol oxidation. Subsequently, the kinetic constants for these three reactions are characterized for various catalyst loadings. The model predicted that methanol undergoes electrochemical adsorption on the Pt/C cathode catalyst layer, followed by both electrochemical and chemical oxidation. The overpotential loss due to methanol oxidation on the cathode with 2 mg/cm 2 catalyst loading is as large as 80 mV at 20 mA/cm 2 . Our model indicated that most of the methanol adsorbed on the cathode catalyst undergoes purely chemical oxidation with oxygen and causes mass transport limitations for oxygen electro-reduction. We also found that the transport of methanol to the anode catalyst layer was significantly enhanced by the convection of CO 2 bubbles towards the flow field. This model should prove useful in optimizing the supply rates of methanol and oxygen in DMFCs.
Author: Srikanth Arisetty Publisher: ISBN: 9781124240503 Category : Fuel cells Languages : en Pages :
Book Description
Direct Methanol Fuel Cells (DMFCs) have been demonstrated extensively as electrical power sources for portable applications. In DMFCs, the chemical energy stored in methanol is converted directly to electrical energy through a number of chemical, transport and kinetic processes. The overall efficiency of the DMFC system can be improved by optimizing these processes with precise control over operating conditions. The goal of this research is to evaluate optimal operating conditions and system design for improving the DMFC's electrical performance through a combination of experimental strategies and process models. A DMFC system incorporating metal foams as the flow field was designed to increase system efficiency. The influence of metal foam parameters and operating conditions on fuel cell performance was investigated. Our results indicated that due to the opposing effects of methanol concentration on anode and cathode kinetics, there exists an optimal value of methanol concentration at each current density that will yield the highest electrical performance. A control algorithm employing feedback from the fuel cell voltage was implemented to dynamically adjust the methanol feed concentration for peak DMFC performance. Additionally, water and methanol crossover fluxes across the membrane were also measured to understand their transport rates under different conditions. The physico-chemical processes in DMFCs were investigated by developing an accurate mathematical model coupling mass transport with reaction kinetics within the five-layer membrane electrode assembly of the DMFC. An experimental scheme was developed to measure the overpotential contributions of anode methanol oxidation, cathode oxygen reduction and cathode methanol oxidation. Subsequently, the kinetic constants for these three reactions are characterized for various catalyst loadings. The model predicted that methanol undergoes electrochemical adsorption on the Pt/C cathode catalyst layer, followed by both electrochemical and chemical oxidation. The overpotential loss due to methanol oxidation on the cathode with 2 mg/cm 2 catalyst loading is as large as 80 mV at 20 mA/cm 2 . Our model indicated that most of the methanol adsorbed on the cathode catalyst undergoes purely chemical oxidation with oxygen and causes mass transport limitations for oxygen electro-reduction. We also found that the transport of methanol to the anode catalyst layer was significantly enhanced by the convection of CO 2 bubbles towards the flow field. This model should prove useful in optimizing the supply rates of methanol and oxygen in DMFCs.
Author: Publisher: Academic Press ISBN: 0123868750 Category : Technology & Engineering Languages : en Pages : 481
Book Description
Fuel cells are attractive electrochemical energy converters featuring potentially very high thermodynamic efficiency factors. The focus of this volume of Advances in Chemical Engineering is on quantitative approaches, particularly based on chemical engineering principles, to analyze, control and optimize the steady state and dynamic behavior of low and high temperature fuel cells (PEMFC, DMFC, SOFC) to be applied in mobile and stationary systems. - Updates and informs the reader on the latest research findings using original reviews - Written by leading industry experts and scholars - Reviews and analyzes developments in the field
Author: Kingshuk Dutta Publisher: Elsevier ISBN: 0128191597 Category : Technology & Engineering Languages : en Pages : 565
Book Description
Direct Methanol Fuel Cell Technology presents the overall progress witnessed in the field of DMFC over the past decade, highlighting the components, materials, functions, properties and features, designs and configurations, operations, modelling, applications, pros and cons, social, political and market penetration, economics and future directions. The book discusses every single aspect of DMFC device technology, the associated advantages and drawbacks of state-of-the-art materials and design, market opportunities and commercialization aspects, and possible future directions of research and development. This book, containing critical analyses and opinions from experts around the world, will garner considerable interest among actual users/scientists/experts. - Analyzes developments of membrane electrolytes, electrodes, catalysts, catalyst supports, bipolar plates, gas diffusion layers and flow channels as critical components of direct methanol fuel cells - Includes modeling of direct methanol fuel cells to understand their scaling up potentials - Discusses commercial aspects of direct methanol fuel cells in terms of market penetration, end application, cost, viability, reliability, social and commercial perception, drawbacks and prospects
Author: Lindiwe Khotseng Publisher: BoD – Books on Demand ISBN: 0854661107 Category : Technology & Engineering Languages : en Pages : 124
Book Description
This book provides a comprehensive overview of methanol fuel. It reviews challenges and solutions in using methanol fuel in the transportation sector. Methanol is also used as the fuel in direct methanol fuel cells (DMFCs), and thus, the book reviews their working principles, performance, challenges, solutions, and applications. It also explores new developments in anode and cathode electrocatalysts, with an emphasis on nanostructured carbon support materials and their structure, electrochemical properties, and performance.
Author: Horacio R. Corti Publisher: Springer Science & Business Media ISBN: 9400777086 Category : Science Languages : en Pages : 377
Book Description
Direct Alcohol Fuel Cells: Materials, Performance, Durability and Applications begins with an introductory overview of direct alcohol fuel cells (DAFC); it focuses on the main goals and challenges in the areas of materials development, performance, and commercialization. The preparation and the properties of the anodic catalysts used for the oxidation of methanol, higher alcohols, and alcohol tolerant cathodes are then described. The membranes used as proton conductors in DAFC are examined, as well as alkaline membranes, focusing on the electrical conductivity and alcohol permeability. The use of different kinds of carbon materials as catalyst supports, gas diffusion layers, and current collectors in DAFC is also discussed. State of the art of the modeling is used to estimate performance and durability. The closing chapter reviews the use of DAFC in portable equipment and mobile devices and features a detailed discussion on the mechanisms of component degradation which limits their durability. This book is written to facilitate the understanding of DAFC technology, applications, and future challenges. It is an excellent introduction for electrochemical and material engineers interested in small fuel cells as portable energy sources, scientists focused on materials science for energy production and storage, as well as policy-makers in the area of renewable energies.
Author: Ramiz Gültekin Akay Publisher: Academic Press ISBN: 0128186240 Category : Science Languages : en Pages : 328
Book Description
Direct Liquid Fuel Cells is a comprehensive overview of the fundamentals and specificities of the use of methanol, ethanol, glycerol, formic acid and formate, dimethyl ether, borohydride, hydrazine and other promising liquid fuels in fuel cells. Each chapter covers a different liquid fuel-based fuel cell such as: Anode catalysts of direct methanol fuel cells (DMFCs), future system designs and future trends for direct ethanol fuel cells (DEFCs), development of catalysts for direct glycerol fuel cells (DGFCs), the mechanisms of the reactions taking place at the anode and cathode electrodes, and the reported anode catalysts for direct formic acid fuel cell (DFAFC) and direct formate fuel cell (DFFC), characteristics of direct dimethyl ether fuel cell (DDMEFC), including its electrochemical and operating systems and design, the developments in direct borohydride fuel cells, the development of catalysts for direct hydrazine fuel cells (DHFCs), and also the uncommonly used liquids that have a potential for fuel cell applications including 2-propanol, ethylene glycol, ascorbic acid and ascorbate studied in the literature as well as utilization of some blended fuels. In each part, the most recent literature is reviewed and the state of the art is presented. It also includes examples of practical problems with solutions and a summarized comparison of performance, advantages, and limitations of each type of fuel cell discussed. Direct Liquid Fuel Cells is not a typical textbook but rather designed as a reference book of which any level of students (undergraduate or graduate), instructors, field specialists, industry and general audience, who benefit from current and complete understanding of the many aspects involved in the development and operation of these types of fuel cells, could make use of any chapter when necessary. Presents information on different types of direct liquid fuel cells. Explores information under each section, for specific fuel-based fuel cells in more detail in terms of the materials used. Covers three main sections: direct alcohol, organic fuel-based and inorganic fuel-based fuel cells
Author: Guoyan Hou Publisher: ISBN: 9781109926262 Category : Languages : en Pages : 114
Book Description
In this dissertation three topics were studied: CO tolerance of Pt and PtRu alloy; methanol oxidation on Pt and PtRu electrodes; the membrane degradation in polymer electrolyte fuel cells.
Author: Alexandra M. F. R. Pinto Publisher: Academic Press ISBN: 0128118989 Category : Technology & Engineering Languages : en Pages : 356
Book Description
Direct Alcohol Fuel Cells for Portable Applications: Fundamentals, Engineering and Advances presents the fundamental concepts, technological advances and challenges in developing, modeling and deploying fuel cells and fuel cell systems for portable devices, including micro and mini fuel cells. The authors review the fundamental science of direct alcohol fuel cells, covering, in detail, thermodynamics, electrode kinetics and electrocatalysis of charge-transfer reactions, mass and heat transfer phenomena, and basic modeling aspects. In addition, the book examines other fuels in DAFCs, such as formic acid, ethylene glycol and glycerol, along with technological aspects and applications, including case studies and cost analysis. Researchers, engineering professionals, fuel cell developers, policymakers and senior graduate students will find this a valuable resource. The book's comprehensive coverage of fundamentals is especially useful for graduate students, advanced undergraduate students and those new to the field. - Provides a comprehensive understanding of the fundamentals of DAFCs and their basic components, design and performance - Presents current and complete information on the state-of-the-art of DAFC technology and its most relevant challenges for commercial deployment - Includes practical application examples, problems and case studies - Covers the use of other fuels, such as formic acid, ethylene glycol and glycerol
Author: Christoph Hartnig Publisher: Elsevier ISBN: 0857095471 Category : Technology & Engineering Languages : en Pages : 437
Book Description
Polymer electrolyte membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs) technology are promising forms of low-temperature electrochemical power conversion technologies that operate on hydrogen and methanol respectively. Featuring high electrical efficiency and low operational emissions, they have attracted intense worldwide commercialization research and development efforts. These R&D efforts include a major drive towards improving materials performance, fuel cell operation and durability. In situ characterization is essential to improving performance and extending operational lifetime through providing information necessary to understand how fuel cell materials perform under operational loads.This two volume set reviews the fundamentals, performance, and in situ characterization of PEMFCs and DMFCs. Volume 1 covers the fundamental science and engineering of these low temperature fuel cells, focusing on understanding and improving performance and operation. Part one reviews systems fundamentals, ranging from fuels and fuel processing, to the development of membrane and catalyst materials and technology, and gas diffusion media and flowfields, as well as life cycle aspects and modelling approaches. Part two details performance issues relevant to fuel cell operation and durability, such as catalyst ageing, materials degradation and durability testing, and goes on to review advanced transport simulation approaches, degradation modelling and experimental monitoring techniques.With its international team of expert contributors, Polymer electrolyte membrane and direct methanol fuel cell technology Volumes 1 & 2 is an invaluable reference for low temperature fuel cell designers and manufacturers, as well as materials science and electrochemistry researchers and academics. - Covers the fundamental science and engineering of polymer electrolyte membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs), focusing on understanding and improving performance and operation - Reviews systems fundamentals, ranging from fuels and fuel processing, to the development of membrane and catalyst materials and technology, and gas diffusion media and flowfields, as well as life cycle aspects and modelling approaches - Details performance issues relevant to fuel cell operation and durability, such as catalyst ageing, materials degradation and durability testing, and reviews advanced transport simulation approaches, degradation modelling and experimental monitoring techniques
Author: Srikanth Arisetty
Author: Srikanth Arisetty
Author: 
Author: Kingshuk Dutta
Author: Pertti S. Kauranen
Author: Lindiwe Khotseng
Author: Horacio R. Corti
Author: Ramiz Gültekin Akay
Author: Guoyan Hou
Author: Alexandra M. F. R. Pinto
Author: Christoph Hartnig