Carbonate fuel cell

Molten Carbonate Fuel Cell. The electrolyte ia the MCFC is usually a combiaation of alkah (Li, Na, K) carbonates retaiaed ia a ceramic matrix of LiA102 particles. The fuel cell operates at 600 to 700°C where the alkah carbonates form a highly conductive molten salt and carbonate ions provide ionic conduction. At the operating temperatures ia MCFCs, Ni-based materials containing chromium (anode) and nickel oxide (cathode) can function as electrode materials, and noble metals are not required. 

Hydrogen use as a fuel in fuel cell appHcations is expected to increase. Fuel cells (qv) are devices which convert the chemical energy of a fuel and oxidant directiy into d-c electrical energy on a continuous basis, potentially approaching 100% efficiency. Large-scale (11 MW) phosphoric acid fuel cells have been commercially available since 1985 (276). Molten carbonate fuel cells (MCFCs) ate expected to be commercially available in the mid-1990s (277). 

Not all of the gas is wasted. About 300 MW of electricity is generated from landfills. A variety of electric generation systems have been employed by a small number of developers. Most projects use simple technology and are small (2—10 MW). However, an EPRI study has estimated that landfill gas resources in the United States could support 6,000 MW of generation if utilized in 2-MW-sized carbonate fuel cells. Constmction on the world s first utihty-scale direct carbonate fuel cell demonstration was begun in California. If successful, EPRI estimates that precommercial 3-MW plants based on this design could become available by the end of this decade at an installed cost of 17,000/kW. 

Molten Carbonate Fuel Cell The electrolyte in the MCFC is a... 

Molten Carbonate Fuel Cell developed by Baur (1921)... 

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. 

The Surface Fractal Investigatioii of Anode Electrode of Molten Carbonate Fuel Cell... 

In order to describe the geometrical and structural properties of several anode electrodes of the molten carbonate fuel cell (MCFC), a fractal analysis has been applied. Four kinds of the anode electrodes, such as Ni, Ni-Cr (lOwt.%), Ni-NiaAl (7wt.%), Ni-Cr (5wt.%)-NijAl(5wt.%) were prepared [1,2] and their fractal dimensions were evaluated by nitrogen adsorption (fractal FHH equation) and mercury porosimetry. These methods of fractal analysis and the resulting values are discussed and compared with other characteristic methods and the performances as anode of MCFC. 

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

Figure 28. Isotherms of the shear viscosities of (Li, Na)2C03. (Reprinted from Y. Sato, T. Yamamura, H. Zhu, M. Endo, T. Yamazaki, H. Kato, and T. Ejima, Viscosities of Alkali Carbonate Melts for MCFC, in Carbonate Fuel Cell Technology, D. Shores, H. Mam, I. Uchida, and J. R. Selman, eds., p. 427, Fig. 9, 1993. Reproduced by permission of the Electrochemical Society, Inc.)...

Proceedings of the Third International Symposium on Carbonate Fuel Cell Technology, Ed. by D. Shores, H. Mara, I. Uchida, and I R. Sehnan, The Electrochemical Society, Pennington, NJ, 1993, p. 416. 

High-temperature molten-carbonate fuel cells (MCFCs). The electrolyte is a molten mixture of carbonates of sodium, potassium, and lithium the working temperature is about 650°C. Experimental plants with a power of up to... 

Schmidt TJ, Gasteiger HA, Behm RJ. 1999b. Rotating disk electrode measurements on a high-surface area Pt/Vulcan carbon fuel cell catalyst. J Electrochem Soc 146 1296-1304. 

Just as the aqueous, alkaline fuel cell can be adopted to C02 separation and concentration, the molten carbonate fuel cell (MCFC) can function in this application as well. Recall that the MCFC cathode operates with the net reaction... 

Fig. 23. (a) Experimental IR-free overpotentials in MCFC-based separator. Cell performance 0.25% C02 Feed. All curves calculated [32] (b) C02 production scheme using molten carbonate fuel cell stack. 

There are six different types of fuel cells (Table 1.6) (1) alkaline fuel cell (AFC), (2) direct methanol fuel cell (DMFC), (3) molten carbonate fuel cell (MCFC), (4) phosphoric acid fuel cell (PAFC), (5) proton exchange membrane fuel cell (PEMFC), and (6) the solid oxide fuel cell (SOFC). They all differ in applications, operating temperatures, cost, and efficiency. 

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. 

Molten carbonate fuel cells use a mixture of lithium and potassium carbonate as an electrolyte and have an OT of 630 to 650°C. 

Advanced power generation cycles that combine high-temper-ature fuel cells and gas turbines, reciprocating engines, or another fuel cell are the hybrid power plants of the future. As noted, these conceptual systems have the potential to achieve efficiencies greater than 70% and projected to be commercially ready by the year 2010 or sooner. The hybrid fuel cell/turbine (FC/T) power plant will combine a high-temperature, conventional molten carbonate fuel cell or a solid oxide... 

Ghezell-Ayagh et al. (2001) An explicit model for direct reforming carbonate Fuel Cell stack, IEEE Trans. Energy Conversion, Vol. 16, No. 3. 

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