Hydrocarbons fuel cells using

In the case of a hydrocarbon fuel-cell using a protonic conductor, ethane is supplied to the anode compartment and the following pyrolysis reaction occurs exothermically. 

Fuel reforming is popular way for hydrogen production for fuel cell use. Hydrocarbons are used for the fuel resource. Methane (CH4) steam reforming process consists of the following two gas phase reactions with various catalysts. 

When a fuel cell consumes natural gas or other hydrocarbons, it produces some carbon dioxide, though much less than burned fuel. Advanced fuel cells using natural gas, for example, could potentially reduce carbon dioxide emissions by 60% compared to a conventional coal plant and by 25% compared to modern natural gas plants. 

Fuel cells using directly liquid fuels are advantageous in this aspect. Methanol, formaldehyde (water solution), formic acid (water solution) and hydrazine are among fuels relatively easy to oxidize electrochemically. Alcohol and hydrocarbon with larger molecular weight are much harder to oxidize completely to C02- Other qualifications to be considered are price, availability, safety, energy density and ease of handling. 

A primary issue in the operation of any fuel cell using hydrocarbon fuels, whether or not steam is present with the hydrocarbon fuel, is the requirement... 

T) The reformer section processes hydrocarbon fuel for fuel cell use... 

A fusion between these direct hydrocarbon proposals and IT/SOFCs such as that of the Mitsubishi Materials Corp. (Section 4.5), or that of Ceres Power Ltd (Section 4.6), could make a hugely competitive, simplified and cheaper future system, with further major development potential to take account of the points in Appendix A of this book, that is fuel cells allied to concentration cell circulators, namely complete fuel cells. Such a development will await judgement of this book, and departure into the history of the application of combustion theory to fuel cells using isothermal oxidation. 

The selective ODS has shown many potential advantages for deep desulfurization of the fuels for fuel cell applications, because the process usually has higher desulfurization capacity than the adsorption desulfurizaton, and also can run at mild operating conditions without the use of H2. For ODS of liquid hydrocarbons fuels, direct use of oil-soluble peroxides or 02 as oxidants in an ODS process is greatly attractive, as the process does not involve a complicated biphasic oil-aqueous solution system. The key in ODS is how to increase the oxidation selectivity for the sulfur compounds. 

The other fuel cells can use hydrogen as the fuel without a problem, but they were primarily developed to function on hydrocarbon fuels. Their use will continue for industrial applications but in this book only the solid polymer fuel cells will be considered. 

Onboard reforming for fuel cells, uses catalytic reactions to convert conventional hydrocarbon fuels, such as gasoline or methanol, into hydrogen that fuel cells use to produce electricity to power vehicles. 

Ford Motor Corporation Developed several sedan and SUV-sized fuel cell vehicles based on methanol reformers and stored hydrogen. Uses Ballard FC electric powertrain. Also is collaborating with Mobil on a fuel processor to extract hydrogen from hydrocarbon fuel cell vehicles. 

Most important in these processes is an active cathode. In most cases finely divided platinum is used for this purpose. Unsupported platinum, particularly the one reduced from Adams catalyst, and carbon-supported platinum electrocatalysts are effective in reducing the amount of platinum required for a given amount of power from a hydrocarbon fuel cell. A propane-oxygen fuel cell, which uses 10 mg Pt per cm supported on carbon can deliver about 35 mW cm using a hydrofluoric acid electrolyte at 105... 

To a certain extent, the decline of interest in fuel cells was due to difficulties in the conunercial realization of earlier achievements. Despite the demonstration that low-temperature electrochemical oxidation of hydrocarbons is basically possible, reaction rates realized in practice were too low, and the amounts of platinum-metal catalyst required to achieve them were so large that the economic prospects of fuel cells using these reactions were very poor. Platinum catalysts were used in most of the fuel cell built, despite the fact that in many studies it had been shown that nonplatinum catalysts could be useful for hydrogen and oxygen electrodes. For economic reasons, the number of potentially interested users decreased gradually. The financial support of work on fuel cells decreased correspondingly. 

Solid oxide fuel cell - Similar to a MCFC, a SOFC is also a kind of high temperature fuel cell working at around 1000°C. Solid ceramic material hke yttria-stabhized zitconia is employed as the electrolyte. The internal reform reaction of fuel makes SOFC flexible to various hydrocarbon fuels without using a fuel reform system. However, the sulfur tolerance of SOFC is poor. Because of the slow start up and high operation temperature, SOFC is suitable to large-scale stationary power applications with heat cogeneration. 

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