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00011 Elucidation of the nature of organic nitrogen in the Argonne premium coals
01 Elucidation of the nature of organic nitrogen in the 98100011 Argonne premium coals Winans, R. E. and Tomczyk, N. A. DGMK Tagungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume l), 151-154. The study aims to give detailed information on the types of nitrogen compounds in coals as a function of rank and age. Desorption highresolution mass spectrometry was used to examine both whole coals and their pyridine extracts. Nitrogen compounds tend to have larger ring numbers compared to all other aromatic clusters. In low rank coals the majority of N-containing compounds have one or more oxygen atoms. The most abundant group of molecules have a N plus two 0 atoms and an average ring size between four and five. It has been demonstrated that many of these molecules may be derived from alkaloids. In the higher rank coals, the average ring size increases to seven for the medium volatile Upper Freeport coal. These multiple ring N compounds play an important role in coal processing and in NO, production and elimination in combustion. Estimation of hydrogen bondings in coal utilizing 9810007 2 FTIR and differential scanning calorimetry (DSC) Mae, K. and Miura, K. Sekitan Kagaku Kaigi Happy0 Ronbunshu, 1996, 33, 153-156. (In Japanese) The authors introduce a new method for estimating the hydrogen bondings in coal using DSC and FTIR. Utilizing the equations proposed by K. F. Purcell and R. S. Drago (1967) for relating the OH bond energy, AEou, the energy of formation of a hydrogen bonding, Eun, and the OH wavenumber shift on adduct formation of phenol with donor, an equation was developed. This equation relates the enthalpy difference, AH, and the OH wavenumber shift between raw coal and a coal in a different state. Since both AH and AvoH are measurable, an equation relating Eun and Avou could be the strength distribution of hydrogen established. Using this equation, bonding in Taiheiyo coal was estimated. The peak value of hydrogen bondings of the coal is 20 kJ/mol-OH. The method represented the change in the hydrogen bondings through heat treatment well. Evaluation of paramagnetic species in coals with 9810007 3 iodine doping technique Aizawa, S. et al. Sekitan Kagaku Kaigi Happy0 Ronbunshu, 1996, 33, 149152. (In Japanese) Measurements of EPR power saturation for both original and iodine-doped coals were carried out ‘to evaluate paramagnetic species in the coals. The EPR spectra of high rank coal consist of two components, one broad and one narrow signal. The power saturation characteristics of the broad signal changed with iodine doping, while that of narrow signal did not change. No significant change was observed in EPR spectra and power saturation characteristics in low rank coal with iodine doping. Flocculation and settling behavior of coking and 9810007 4 non-coking coal fines. A comparative study Karmakar, N. C. et al. DGMK Tagungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume I), 531-534. Two coal fines suspension were studied in relation to their flocculation and natural settling behaviour. Four commercial flocculants and two polysaccharide-based graft copolymers were used. Much greater resistance to settling was observed in the non-coking coal suspension. The performance of amylopectin-r-polyacrylamide and Superfloc N300 for flocculation of coking coal suspensions is better than of other commercial flocculants. Geochemistry of beryllium in coals: ecological 9810007 5 aspect Kizil’shtein, L. Y. Geokhimiya, 1997, (3), 336-342. (In Russian) Coal-fired power stations contaminate the air with beryllium, a highly toxic element occurring in coal. Beryllium geochemistry in coal is discussed. Be emissions in aerosol and gaseous combustion products is assessed. Hazardous beryllium concentrations in coals from selected coal basins of Russia are estimated.
The influence of the humic constituents upon the 98lOOO7 8 nature of thermal conversions of brown coal Butuzova, L. and Krzton, A. DGMK Tagungsber., 1997,9703, (Proceedings ICCS ‘97, Volume 2), 549-552. FT-IR diffuse reflectance spectroscopy was employed to study the relative distribution of various types of C-O bonds in original brown coal (OC), residual coal (RC) after removing humic acids (HA), in pyrolysis products thereof, and in HA. OH groups are the principal form of active 0 in all samples. Their relative number increases, if HA are extracted, whereas HA themselves contain less OH groups. RC is remarkable for the maximum content of aromatic H, minimal content of C-O bonds in relation to C=C bonds, and the highest strength of intermolecular interactions C=O/CHA,,. A method for brown coal pyrolysis with simultaneous preparation of adsorbents, resins, and humic acids with high biological activity is proposed.
Solid fuels (sources,
winning, propetiies)
9810007 7 Inverse gas chromatography determination of some physicochemical parameters of a high rank Colombian coal Baquero-Haeberlin, M. C. and Rincan, J. M. DGMK Tagungsber.. 1997, 9702, (Proceedings ICCS ‘97, Volume I), 107-110. Inverse gas chromatography (IGC), at zero coverage, injecting the series of n-alkanes at 313, 333, 353, and 373 K, was used to determine the dispersive component of the free surface energy of a Colombian semianthracite-type coal (Paramo do Giuerrero). The mass centre determination was used for the retention time instead of the maximum peak in the chromatograms. The free surface energy increased linearly with the C atom number to the alkanes but was not constant due, probably to the conformational structure of the probes. The IGC study of the adsorption process in function of the temperature, provide the respective enthalpy and entropy values. 98lOOO18 Investigation of asphaltenes from bituminous coals to evaluate coal chemical structure Liu, Y. et al. DGMK Tagungsber, 1997, 9702, (Proceedings ICCS ‘97, Volume 1). 127-130. Asphaltenes from coals of different rank were subjected to non-isothermal pyrolysis in a thermobalance at a low heating rate. The mechanistic and kinetic data on decomposition of asphaltenes indicate that functional groups and basic structural units of coals originated from the same deposit but with different rank are similar on account of the similarity of temperature range and shape of gas formation curves. Compared with high molecular weight model compounds, ary-alkyl-ethers, methylene, and bi-arylether bridges between aromatic units and Me groups an aromatic rings, were found in asphaltene structure. In addition, ‘H and “C NMR analyses of asphaltenes show the presence of long side-chains attached to aromatic and hydroaromatic ring systems. Therefore, these lung chains not only exist in the mobile phase of coal molecular structure as it is wellknown, but also work as an integral part of coal macromolecular network. 98100019 Kinetics of solvent-swelling of coal Mureno, G. et al. DGMK Tagungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume I), 219-222. Solvents of different basic strength were used to monitor the kinetics of coal swelling. Cerrejun and Yerbabuena (Colombian coals), Sacer-Endsdorf and Ruhr-Anna (Germany coals) were swollen with THF, pyridine, and butylamine. The swelling index decrease both with solvent basicity and coal rank. With increasing coal rank, the swelling rates are: initially, THF follows Fickian diffusion then follows an anomalous case near case II; pyridine follows anomalous case near Fickian diffusion, whereas the rate with butylamine initially is an anomalous case of transport near to Fickian diffusion. Low-rank coal formation in Poland and the United 98100020 States. Part 1. Zittau Basin, Poland Kasinski, J. R. et al. DGMK Tagungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume l), 35-38. A summary of the results from the collaborative study of Miocene brown coals in the Zittau Basin in south-western Poland is presented. Between 1991 and 1994 the Polish Geological Institute (PGI) and the US Geological Survey (USGS) conducted a joint low-rank coal research project. The main goals of the project were to compare stratigraphic, sedimentary, and geochemical characteristics of low-rank coals from Poland and the US and to assess their potential environmental impacts. The studies were conducted in four basins: the Zittau and Konin brown coal basins in Poland and the Gulf Coast lignite and Powder River sub-bituminous coal basins in the United States. 98looo21 Material design of coal ash-composite. Mechanical strength and ash characteristics Katsuse, K. et al. Hokkaidoritsu Kogyo Shikenjo Hokoku, 1997, 296, 7-14. (In Japanese) Using each of 10 kinds of fly ash from overseas coals, phenolic novolakifly ash (FA) composites, as well as those containing chopped glass fibre were, prepared. The effects of the kind of FA on mechanical properties were investigated and the properties were closely related to the bulk density of FA. The chemical compositions and powder characteristics of each FA used were given in tables and graphs in detail. 98100022 Mining and geological characteristics of the LvovVolyn coal basin Shul’ga, V. F. et al. Ugol’ Ukr., 1995, (12) 2-9. (In Russian) The paper studies the geological structure of the Lvov-Volyn Basin and the geology, reserves, and quality of its coal deposits. 98100023 Modelling of the relation between trace elements and three species of sulfur in coal Lu, X. et al. Huanjing Huaxue, 1997, 16, (4), 306-310. (In Chinese) Seven parts of Qingshan bituminous coal classified according to specific gravity had their trace elements Be, Cd, Co, Cu, Pb, Cr, Ni, As and sulfur forms determined. Close relationships between the content of trace elements and sulfur species was found and a regression model of three variables was established to fit the data of trace elements and sulfates, sulfides and organic sulfur in coal and used for trace elements prediction. The results were satisfactory.
Fuel and Energy Abstracts
January 1998
3
The influence of the humic constituents upon the 98lOOO7 8 nature of thermal conversions of brown coal Butuzova, L. and Krzton, A. DGMK Tagungsber., 1997,9703, (Proceedings ICCS ‘97, Volume 2), 549-552. FT-IR diffuse reflectance spectroscopy was employed to study the relative distribution of various types of C-O bonds in original brown coal (OC), residual coal (RC) after removing humic acids (HA), in pyrolysis products thereof, and in HA. OH groups are the principal form of active 0 in all samples. Their relative number increases, if HA are extracted, whereas HA themselves contain less OH groups. RC is remarkable for the maximum content of aromatic H, minimal content of C-O bonds in relation to C=C bonds, and the highest strength of intermolecular interactions C=O/CHA,,. A method for brown coal pyrolysis with simultaneous preparation of adsorbents, resins, and humic acids with high biological activity is proposed.
Solid fuels (sources,
winning, propetiies)
9810007 7 Inverse gas chromatography determination of some physicochemical parameters of a high rank Colombian coal Baquero-Haeberlin, M. C. and Rincan, J. M. DGMK Tagungsber.. 1997, 9702, (Proceedings ICCS ‘97, Volume I), 107-110. Inverse gas chromatography (IGC), at zero coverage, injecting the series of n-alkanes at 313, 333, 353, and 373 K, was used to determine the dispersive component of the free surface energy of a Colombian semianthracite-type coal (Paramo do Giuerrero). The mass centre determination was used for the retention time instead of the maximum peak in the chromatograms. The free surface energy increased linearly with the C atom number to the alkanes but was not constant due, probably to the conformational structure of the probes. The IGC study of the adsorption process in function of the temperature, provide the respective enthalpy and entropy values. 98lOOO18 Investigation of asphaltenes from bituminous coals to evaluate coal chemical structure Liu, Y. et al. DGMK Tagungsber, 1997, 9702, (Proceedings ICCS ‘97, Volume 1). 127-130. Asphaltenes from coals of different rank were subjected to non-isothermal pyrolysis in a thermobalance at a low heating rate. The mechanistic and kinetic data on decomposition of asphaltenes indicate that functional groups and basic structural units of coals originated from the same deposit but with different rank are similar on account of the similarity of temperature range and shape of gas formation curves. Compared with high molecular weight model compounds, ary-alkyl-ethers, methylene, and bi-arylether bridges between aromatic units and Me groups an aromatic rings, were found in asphaltene structure. In addition, ‘H and “C NMR analyses of asphaltenes show the presence of long side-chains attached to aromatic and hydroaromatic ring systems. Therefore, these lung chains not only exist in the mobile phase of coal molecular structure as it is wellknown, but also work as an integral part of coal macromolecular network. 98100019 Kinetics of solvent-swelling of coal Mureno, G. et al. DGMK Tagungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume I), 219-222. Solvents of different basic strength were used to monitor the kinetics of coal swelling. Cerrejun and Yerbabuena (Colombian coals), Sacer-Endsdorf and Ruhr-Anna (Germany coals) were swollen with THF, pyridine, and butylamine. The swelling index decrease both with solvent basicity and coal rank. With increasing coal rank, the swelling rates are: initially, THF follows Fickian diffusion then follows an anomalous case near case II; pyridine follows anomalous case near Fickian diffusion, whereas the rate with butylamine initially is an anomalous case of transport near to Fickian diffusion. Low-rank coal formation in Poland and the United 98100020 States. Part 1. Zittau Basin, Poland Kasinski, J. R. et al. DGMK Tagungsber., 1997, 9702, (Proceedings ICCS ‘97, Volume l), 35-38. A summary of the results from the collaborative study of Miocene brown coals in the Zittau Basin in south-western Poland is presented. Between 1991 and 1994 the Polish Geological Institute (PGI) and the US Geological Survey (USGS) conducted a joint low-rank coal research project. The main goals of the project were to compare stratigraphic, sedimentary, and geochemical characteristics of low-rank coals from Poland and the US and to assess their potential environmental impacts. The studies were conducted in four basins: the Zittau and Konin brown coal basins in Poland and the Gulf Coast lignite and Powder River sub-bituminous coal basins in the United States. 98looo21 Material design of coal ash-composite. Mechanical strength and ash characteristics Katsuse, K. et al. Hokkaidoritsu Kogyo Shikenjo Hokoku, 1997, 296, 7-14. (In Japanese) Using each of 10 kinds of fly ash from overseas coals, phenolic novolakifly ash (FA) composites, as well as those containing chopped glass fibre were, prepared. The effects of the kind of FA on mechanical properties were investigated and the properties were closely related to the bulk density of FA. The chemical compositions and powder characteristics of each FA used were given in tables and graphs in detail. 98100022 Mining and geological characteristics of the LvovVolyn coal basin Shul’ga, V. F. et al. Ugol’ Ukr., 1995, (12) 2-9. (In Russian) The paper studies the geological structure of the Lvov-Volyn Basin and the geology, reserves, and quality of its coal deposits. 98100023 Modelling of the relation between trace elements and three species of sulfur in coal Lu, X. et al. Huanjing Huaxue, 1997, 16, (4), 306-310. (In Chinese) Seven parts of Qingshan bituminous coal classified according to specific gravity had their trace elements Be, Cd, Co, Cu, Pb, Cr, Ni, As and sulfur forms determined. Close relationships between the content of trace elements and sulfur species was found and a regression model of three variables was established to fit the data of trace elements and sulfates, sulfides and organic sulfur in coal and used for trace elements prediction. The results were satisfactory.
Fuel and Energy Abstracts
January 1998
3