Methanol fuel distribution

Fuel Flexible Vehicles. Using dedicated alcohol fuel vehicles pointed to the importance of a wide distribution of fueling stations. Methanol-fueled vehicles require refueling more often than gasoline vehicles. 

However, there are several issues with widespread methanol usage. Methanol production from natural gas is relatively inefficient ( 67%), and this largely offsets the vehicular improvement in efficiency and carbon dioxide reduction (since gasoline can be made with "85% efficiency from oil). Additionally, the PEM fuel cell demands very pure methanol, which is difficult to deliver using existing oil pipelines and may require a new fuel distribution infrastructure. 

Determination of Current Distributions Governed by Laplace s Equation Direct Methanol Fuel Cells From a Twentieth Century Electrochemist s Dream to a Twenty-First Century Emerging Technology West, A. C. Newman, J. Lamy, C. Ueger, J.-M. Srinivasan, S. 23... 

Fuels that are most directly suited to the fuel cell are the most difficult and costly to produce and distribute. Gasoline and methanol are the leading candidates to power fuel cell engines. Both the gasoline and methanol fuel cell vehicles should be more fully developed prior to making a commercial decision on fuel choice. 

Methanol is distributed throughout the U.S. as an industrial chemical. Most suppliers can be found in the phone book under chemical or industrial supplies. The price of methanol in small quantities is much higher than if delivered in large bulk quantities (such as how petroleum fuels are delivered). 

Methanol is completely soluble in water unlike gasoline and diesel fuel which are essentially non-soluble in water. (Actually, gasoline and diesel fuel will absorb a very small amount of water, depending on the amount of aromatics present.) This could prove to be a problem in commerce since the current fuel distribution and storage systems for gasoline and diesel fuel are not water-tight. While water that enters a gasoline or diesel fuel system is a nuisance, it does not immediately... 

Also at Palm Springs, two papers by the Methanol Fuel Cell Alliance (Ballard/BASF/BPAmoco/Daimler Chrysler/Methanex/Statoil) and the Methanol Institute, respectively, portray the existing substantial methanol production, distribution and trading based on natural gas reform/synthesis gas/methanol, as in the Methanex Canada plant. Methanol from biomass is a future possibility. A methanol pump can be fitted within the footprint of many existing diesel/gasoline filling stations, and an Identic refuelling nozzle has been developed in Sweden, to avoid confusion between methanol and alternative fuels. 

Science Applications, Inc., has recently completed a comprehensive technical and economic assessment of producing methanol from biomass feedstocks employing developed gasification technology. This study includes an assessment of biomass availability and the distribution and markets for methanol fuels as well as thermochemical conversion technology. 

Mench, M.M. Wang, C.Y. An in situ method for determination of current distribution in PEM fuel cells applied to a direct methanol fuel cell. J. Electrochem. Soc. 2003,150 (1), A79-A85. 

Whereas uniform distribution of water within the membrane is desired, the permeability of the material to reactants (i.e., hydrogen or methanol and oxygen) has to be low to prevent direct chemical reaction between fuel and oxidant, which may lead to hotspots and, eventually, pinhole formation. Methanol permeability is a major challenge in the direct methanol fuel cell (DMFC), largely because methanol transport is strongly correlated with water transport, leading to significant penalties in fuel efficiency and poor cathode performance [189]. 

Higuchi E, Asano N, Miyatake K, Uchida H, Watanabe M (2007) Distribution profile of water and supression of methanol crossover in sulfonated polyimide electrolyte membrane for direct methanol fuel cells. Eiectrochim Acta 52 5272-5280... 

An intrinsic time-dependent one-dimensional (ID) model and a macro two-dimensional (2D) model for the anode of the DMFC are presented in [178]. The two models are based on the dual-site mechanism, which includes the coverage of intermediate species of methanol, OH, and CO on the surface of Pt and Ru. The intrinsic ID model focused on the analysis of the effects of operating temperature, methanol concentration, and overpotential on the transient response. The macro 2D model emphasizes the dimensionless distributions of methanol concentration, overpotential and current density in the CL which were affected by physical parameters such as thickness, specific area, and operating conditions such as temperature, bulk methanol concentration, and overpotential. The models were developed and solved in the PDEs module of COMSOL Multiphysics, giving good agreement with experimental data. The dimensionless distributions of methanol concentration, overpotential, and current density and the efficiency factor were calculated quantitatively. The models can be used to give accurate simulations for the polarizations of methanol fuel cell. 

The anode plate at the center of the stack used as a methanol reservoir permit a more efficient fuel distribution and reduces the stack weight. In Fig. 9.4 (right) six dual side stacks were connected in series to generate a 600 mW mobile phone charger that developed a power density of 25 mW.cm. ... 

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