Fuel active components

Aragane J, Murahashi T, Odaka T. 1988. Change of Pt distribution in the active components of phosphoric acid fuel cell. J Electrochem Soc 135 844-850. 

Many hydrocarbons bind quite tightly to soil components, and are thereby less available to microbial degradation. Intrinsic biodegradation occurs, but it usually only removes the lightest refined products, such as gasoline, diesel and jet fuel. Active intervention is typically required. Usually the least expensive approach is in situ remediation, typically with the addition of nutrients, and the attempted optimization of moisture and oxygen by tilling. 

In the past ten years the number of chemistry-related research problems in the nuclear industry has increased dramatically. Many of these are related to surface or interfacial chemistry. Some applications are reviewed in the areas of waste management, activity transport in coolants, fuel fabrication, component development, reactor safety studies, and fuel reprocessing. Three recent studies in surface analysis are discussed in further detail in this paper. The first concerns the initial corrosion mechanisms of borosilicate glass used in high level waste encapsulation. The second deals with the effects of residual chloride contamination on nuclear reactor contaminants. Finally, some surface studies of the high temperature oxidation of Alloys 600 and 800 are outlined such characterizations are part of the effort to develop more protective surface films for nuclear reactor applications. ... 

Related systems It should be noted that specific properties for applications could be enhanced by using solid solutions, doped materials, and composites, instead of pure ceria. For example, ceria-zirconia solid solution is a well known ceria based material for enhanced OSC and high ionic conductivity for solid state fuel cell components. It is also used in the three way catalysts for automobile waste gas cleaning, because of the improved thermal stability, surface area, and reducibility. The synthesis, structure, and properties of ceria-zirconia have been actively studied for a long time. Di Monte and Kaspar et al. presented feature articles on the nanostructured ceria—zirconia-mixed oxides. The studies on phase, structures, as well as the microstructures are discussed and reviewed (Di Monte et al., 2004). 

If the ammonia is condensed flrst in the upper part of a reaction tube cooled to 90° K., the reaction proceeds slowly as the vessel is warmed to 150° to 160° K. Ammonia has a vapor pressure of about 1 mm. at 160° K. and reacts slowly as a gas with the solid O2CIF3. Under these conditions the reaction proceeds smoothly without any gas evolution, while the violet color disappears and a white solid is formed. Under the same conditions pure solid CIF3 reacts much more slowly this is to be expected, since, in any reaction with a fuel, the components formed from O2CIF3—i.e., O2 and CIF3—are activated by the endothermic heat of formation of O2CIF3 (AH298 assumed to be equal to + 15 10 kcal. per mole). 

Beryllium-10 Be-10 is an activation product of Be-9. It was identified in several mobile and solid waste streams but exceeded the GQ only in fuel channel components (FCC) at HNA due to the natural Be content of the Zr D-bar fuel component. Laboratories within Magnox Electric do not currently analyse waste for Be-10 therefore the Best Estimate activity in the Nirex... 

Fuel cells, due to their higher efficiency in the conversion of chemical into electrical energy vhth respect to thermo-mechanical cycles, are another major area of R D that has emerged in the last decade. Their effective use, ho vever, still requires an intense effort to develop ne v materials and catalysts. Many relevant contributions from catalysis (increase in efficiency of the chemical to electrical energy conversion and the stability of operations, reduce costs of electrocatalysts) are necessary to make a step for vard in the application of fuel cells out of niche areas. This objective also requires the development of efficient fuel cells fuelled directly vith non-toxic liquid chemicals (ethanol, in particular, but also other chemicals such as ethylene glycol are possible). Together vith improvement in other fuel cell components (membranes, in particular), ethanol direct fuel cells require the development of ne v more active and stable electrocatalysts. 

Noble metal catalysts are highly active for the oxidation of carbon monoxide and therefore widely used in the control of automobile emissions. Numerous recent studies on noble metal-based three-way catalysts have revealed characteristics of good thermal stability and poison resistance(l). Incorporation of rare earth oxides as an additive in automotive catalysts has improved the dispersion and stability of precious metals present in the catalyst as active components(2). Monolith-supported noble-metal catalysts have also been developed(3). However, the disadvantages of noble metal catalysts such as relative scarcity, high cost and requirement of strict air/fuel ratio in three-way function have prompted attention to be focused on the development of non-noble metal alternatives. 

Catalytic activity of the anode material YSZ-cerium dioxide was tested for possible use in fuel-cell reactors, as a high-active component but is sensitive to hydrogen (Nakagawa et al. 2001). 

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