Molten reforming

Impurities can be removed by formation of a gaseous compound, as in the fire-refining of copper (qv). Sulfur is removed from the molten metal by oxidation with air and evolution of sulfur dioxide. Oxygen is then removed by reduction with C, CO, in the form of natural gas, reformed... 

Corrosion Resistance. Zirconium is resistant to corrosion by water and steam, mineral acids, strong alkaUes, organic acids, salt solutions, and molten salts (28) (see also Corrosion and corrosion control). This property is attributed to the presence of a dense adherent oxide film which forms at ambient temperatures. Any break in the film reforms instantly and spontaneously in most environments. 

The PAFC is, however, suitable for stationary power generation, but faces several direct fuel cell competitors. One is the molten carbonate fuel cell (MCFC), which operates at "650°C and uses an electrolyte made from molten potassium and lithium carbonate salts. Fligh-teinperature operation is ideal for stationary applications because the waste heat can enable co-generation it also allows fossil fuels to be reformed directly within the cells, and this reduces system size and complexity. Systems providing up to 2 MW have been demonstrated. 

Dynamic Simulation of Plate-Type Reformer and Combustor System for Molten Carbonate Fuel Cell... 

W. He and Kas Hemmes, Operating characteristics of a reformer for molten carbonate fuel-cell power-generation systems. Fuel Processing Technology, 67 (2000) 61. 

The crystallinity levels in ethylene ionomers are generally low due to their high levels of branching and the clustering of the metal salts. At high temperatures, the clusters dissociate and the individual chains can move independently in the molten state, permitting them to be molded. When the ionomer is cooled dusters reform, crosslinking the chains... 

Cavallaro, S. Freni, S., Ethanol steam reforming in a molten carbonate fuel cell. A preliminary kinetic investigation. International Journal of Hydrogen Energy 1996, 21, 465-469. 

Ghezell-Ayagh et al. (1999) Development of a stack simulatioin model for control study on direct reforming molten carbonate fuel cell power plant, IEEE Trans. Energy Conversion, Vol. 14, No. 4. 

S. Kaneko et al., "Research on On-Site Internal Reforming Molten Carbonate Fuel Cell," 1989 Intemational Gas Research Conference, 1989. 

T. Tanaka, et al., "Development of Internal Reforming Molten Carbonate Fuel Cell Technology," in Proceedings of the 25th lECEC, American Institute of Chemical Engineers, New York, NY, August 1990. 

In general, reforming of the CH4 fuel with excess H2O outside the cell has been practiced both in molten carbonate and solid oxide fuel cell systems in order to produce H2, more reactive on a fuel cell anode, and to avoid the possible deposition of C. This reforming reaction... 

First, we will refer to the direct use of hydrocarbon fuels in an SOFC as direct utilization rather than direct oxidation. Second, we recognize that the broadest definition of direct utilization, exclusive from mechanistic considerations, should include rather conventional use of fuel by internal reforming, with steam being cofed to the fuel cell with the hydrocarbon. Indeed, this nomenclature has been used for many years with molten-carbonate fuel cells. However, because internal reforming is essentially limited to methane and because the addition of steam with the fuel adds significant system complexity, we will focus primarily on systems and materials in which the hydrocarbons are fed to the fuel cell directly without significant amounts of water or oxygen. 

In the molten carbonate fuel cell, methane is used as the fuel. This cell runs at high temperatures and uses a molten mixture of lithium and potassium carbonates as electrolyte. In most such cells, the methane is reformed into hydrogen and carbon monoxide before reacting in the cell ... 

An electrolysis reaction in which the oxidation reaction is not the reverse of the reduction reaction is the electrolysis of molten sodium chloride. Molten sodium chloride (NaCl), with calcium chloride (CaCy added to decrease the melting point, is electrolyzed in a Downs cell, in which the sodium and chlorine products are separated so that sodium chloride does not reform. The following reactions occur ... 

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