Characterization of coals

England, B.M. Mikka, R.A. Bagnall, B.J. Petrographic Characterization of Coal Using Automatic Image Analysis, J. Microscopy. 1979, 116, 329-336. 

Ladesma, R., Compo, P., and Isaacs, L. L., Thermal Characterization of Coal... 

Nelson, E.C., Ghoshal, S., Edwards. J.C., Marsh. G.X., and Luthy, R.G. Chemical characterization of coal tar-water interfacial films, Environ. Sci Technol, 30(3) 1014-1022, 1996. 

The principal advantage of the ion microprobe (as opposed to the Auger microprobe) is the ability to obtain depth profiles for trace elemental species present in the analytical volume. The characterization of coal fly ash clearly illustrates this point (11-14). Auger detection limits are comparable to BSCA, and thus only elements with bulk concentrations greater than 1% by weight in fly ash (Si, Al, Fe, Ca, S, Na, K) can be... 

Granger, J. E. Clark, G. A. 1991. Fuel characterization of coal/shredded tire blends. Proceedings 1991 Conference on Waste Tires as a Utility Fuel. Electric Power Research Institute, Palo Alto, CA, EPRI GS-7538, 5/1-5/14. 

Nathan, Y., Dvorachek, M., Pelly, I. Mimran, U. 1999. Characterization of coal fly ash from Israel. Fuel, 78, 205-213. 

The volume percent of physical components of coal is used as an aid in the characterization of coal for use in carbonization, gasification, and combustion processes. To determine the volume percent of the physical components of coal (ASTM D-2799), the components in a representative crushed coal sample (ASTM D-2797) are identified under a microscope according to their reflectance, other optical properties, and morphology. The proportion of each component in the sample is determined by observation of a statistically adequate number of points and summing those representative of each component. Only area proportions of components are determined on a surface section of a sample. However, the area and volume proportions are the same when the components are distributed randomly throughout the sample. 

All of the papers in this book deal with the chemistry and characterization of coal macerals and, as such, recognize the heterogeneous nature of coal. Coal is, in fact, a rock derived from a variety of plant materials which have undergone a variety of physical and chemical transformations. While a number of chemical studies of coal have found the concept of a single "coal molecule" useful, the papers in this book are aimed at characterizing in some way the various macromolecules that comprise the many kinds of coal macerals. 

In the late 1950 s and early 1960 s the reflectance characterization of coal macerals was used with great success in carbonization studies. For example, it was shown by Spackman et al. (12) that the properties of the various coal macerals... 

Although the characterization of coal macerals on the basis of their fluorescence spectra is a recent innovation, it has already proven to be an excellent fingerprinting tool for the various macerals. In some cases, it is even more sensitive than normal petrographic analysis. The initial results of fluorescence spectral studies show that the various fluorescent macerals in single coals can be statistically discriminated on the basis of their spectral parameters and that even varieties of a single maceral type can be distinguished. Although the spectra obtained at this time are rather broad and not suitable for chemical structure analysis, the potential for structural analysis exists and may be realized with improvements in instrumentation. 

Granger, John E. Fuel Characterization of coal/Shredded Tire Blends. Presented at EPRI Conference Waste Fuels in Utility Boilers. San Jose, CA. January 28, 1991. 

Chemistry and Characterization of Coal Macerals Winans, R. E. Crelling, J. C., Eds. ACS Symposium Series No. 252 American Chemical Society Washington, DC, 1984 pp 65-77. 

Cascade Impactors in the Chemical and Physical Characterization of Coal-Combustion Aerosol Particles... 

Chung, K. E., "Characterization of Coal-Derived Liquids— Relationships to Chemical Structures in Coal," Ph.D. Thesis, University of Utah, June 1980. 

Characterization of Coal-Derived Materials by Matrix Isolation Spectroscopy... 

Coal Liquids to Gas Turbine Fuels. 1. Analytical Characterization of Coal Liquids, Ind. Eng. Chem., Prod. Res. Dev. 1976,15(4), 223-233. 

J. E. Characterization of Coal Liquids Derived from the H-Coal Process, ERDA-BERC/RI-76/10, Nov. 1976. 

Microstructure. The characterization of coal-derived asphaltene is quite similar to that of petroleum-derived asphaltene. Since it is anticipated that coal-derived asphaltene will have acid/neutral and base characteristics (26, 36), the average structure of both must be considered. In Table III, Structure I is amphoteric (or slightly basic), and Structure II is an acid/neutral representation. A mixture of both may be typical of the average structure of a coal-derived asphaltene. At present, we will illustrate this by an asphaltene obtained from coal liquid of the Synthoil process. (The coal is hvAb, West Kentucky, Homestead Seam the coal liquid is obtained by catalytic hydrogenation at 450° C and 4000 psig having %C, 86.7 %H, 8.38 %N, 0.93 %S, 0.09 %Q, 3.2 and %Ash, 0.7.)... 

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