Coal, determination

The conditions of pyrolysis either as low or high temperature carbonization, and the type of coal, determine the composition of Hquids produced, known as tars. Humic coals give greater yields of phenol (qv) [108-95-2] (up to 50%), whereas hydrogen-rich coals give more hydrocarbons (qv). The whole tar and distillation fractions are used as fuels and as sources of phenols, or as an additive ia carbonized briquettes. Pitch can be used as a biader for briquettes, for electrode carbon after coking, or for blending with road asphalt (qv). 

Solids Sampling and Analysis. The coal consumption data is compiled in Table II. The ash, BTU, and sulfur analyses on the coal consumed during the 1-wk test period is presented in Table III. The data from the mercury in coal determinations are given in Table IV. Based on the authors experience with mercury in coal studies, the resulting concentrations are average for eastern United States coals. The author has found the spread in the individual coal determinations to be common when analyzing 0.5-g samples. The data in Tables III and IV show a relation-... 

Figure 5. Methane isotherms on Pittsburgh coal determined in increasing temperature sequence desorption points are solid...

Differences in the degree of metamorphism occurring during the formation of coal determine the different ranks of coal. 

ISO 11722. Hard Coal Determination of Moisture in the General Analysis Test Sample by Drying in Nitrogen. 

ISO. 1994. Hard Coal—Determination of Oxygen Content. International Organization for Standardization, Geneva, Switzerland. 

Some general applications of TG-FTIR are evolved gas analysis, identification of polymeric materials, additive analysis, determination of residual solvents, degradation of polymers, sulphur components from oil shale and rubber, contaminants in catalysts, hydrocarbons in source rock, nitrogen species from waste oil, aldehydes in wood and lignins, nicotine in tobacco and related products, moisture in pharmaceuticals, characterisation of minerals and coal, determination of kinetic parameters and solid fuel analysis. 

Information on the element and mineral content of coals provides only a partial picture of the potential behavior of the trace elements in coal. The picture can be brought into sharper focus if we know an element s mode of occurrence (chemical form). The mode of occurrence of an element in coal determines its technological behavior, environmental impact, and economic potential, and provides insight into the geochemical processes that occurred during coalihcation. 

Treating a bituminous coal with potassium hydroxide in glycols at 250°C yields a largely soluble product that results from the reduction of polycyclic aromatics and the cleavage of aryl ether linkages. The reduction in aromaticity was demonstrated in two ways. First, the fraction of aromatic carbons ( J of the soluble product, which was determined by NMR, was compared with the of the whole coal determined by fluorination. Secondly, the aromatic acids produced in a selective oxidation of both the product and coal were compared, and evidence for ether cleavage was obtained from the oxidation results. The effects of rank and different protic solvents on the reaction were examined. 

The Ultrafine Structure of Coal Determined by Electron Microscopy... 

Wiese, R. G., Jr., Muir, 1. J., and Fyfe, W. S., 1990, Trace element siting in iron sulfides from coal determined by secondary ion mass spectrometry Energy Sources, v. 12, no. 3, p. 251-264. 

In a recent study, measurements were made for a number of coals to verify van Krevelen s correlation (15). Values of C(ar), computed using the Brown-Ladner relation with values of H(al) determined by FT-IR are plotted in Fig. 31 against the ASTM determined values for FC. Also plotted are data for the coals reported by van Krevelen. The values of C(ar) for similar rank coals determined by the two methods are in agreement. Values for C(ar) show a systematic variation with FC but, as noted by van Krevelen, are typically higher than FC. The data seem to contradict the observation that volatile tars have appreciable aromatic contents (see Figs. 27 and 30). The reasons for this correlation are discussed in (15) ... 

ISO. 2011. Hard Coal—Determination of Forms of Sulfur (ISO 157). International Standards Organization, Geneva, Switzerland, 331. 

The determination of the mineral matter content of coal (determined as mineral ash after combustion) has been an essential part of coal evaluation for many years (Shipley, 1962 Rees, 1966 Given and Yarzab, 1978 Huggins et al., 1982 Nadkarni, 1982) (Chapter 8). For example, when coal is cleaned by various processes to reduce the sulfur and mineral content, it is an advantage to be aware of the mineral (ash) content to determine the best cleaning method insofar as the various cleaning methods have different tolerance levels for the mineral constituents of coal. Fnrthermore, the ash content is also a means of assessing the adequacy of the various sampling procednres (Chapter 8), and it is one of the criteria normally specified in contracts between a pnrchaser and a supplier of coal. 

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