High-temperature gases reference materials

The aim with the present paper is to survey the literature on catalytic fuel combustion for high temperature gas turbine applications with emphasis on the progress during the last five years. Reference to work before 1993 can be found in an earlier review from our laboratory. Following a brief introduction to catalytic combustion and a discussion on formation and abatement of emission, state-of-the-art in materials development will be reviewed in Section 3. Recent results from mathematical modelling are covered in Section 4. An update of new concepts of catalytic combustors and advanced pilot-scale tests will be presented in Section 5, where also a case study on a recently finished European project is reported. Finally, deactivation of combustion catalysts is discussed in Section 6 and a spin-off effect of catalytic combustion is recapitulated in Section 7. 

The reaction of metals with gas mixtures such as CO/CO2 and SO2/O2 can lead to products in which the reaction of the oxygen potential in the gas mixture to form the metal oxides is accompanied by the formation of carbon solutions or carbides in the first case, and sulphide or sulphates in the second mixture. Since the most important aspects of this subject relate to the performance of materials in high temperature service, the reactions are referred to as hot corrosion reactions. These reactions frequently result in the formation of a liquid as an intermediate phase, but are included here because the solid products are usually rate-determining in the corrosion reactions. 

In addition to catalytic applications, the perovskite backbone is a key component in modern high-temperature superconductive materials. By definition, a superconductor exhibits no resistance to electrical conductivity, and will oppose an external magnetic field, a phenomenon referred to as the Meissner effect (Figure 2.19). Many pure transition metals e.g., Ti, Zr, Hf, Mo, W, Ru, Os, Ir, Zn, Cd, Hg) and main group metals e.g., Al, Ga, In, Sn, Pb) exhibit superconductivity, many only when exposed to high-pressure conditions. These materials are referred to as Type I or soft superconductors. 

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