Showing papers in "Fuel in 1982"

TL;DR: In this paper, the preparation of coal samples for the determination of hydroxyl content by FTIR is described, and it is concluded that the FTIR method provides good quality infrared spectra on opaque materials such as coal and char.

TL;DR: In this article, the conditions necessary for efficient, small-scale separation of coal macerals are investigated, and an isopycnic density gradient centrifugation (DGC) technique is used to isolate pure macers.

TL;DR: In this article, the average molecular structures of bitumens were investigated and the most probable average structural parameters were calculated without making any assumptions, and average structural models for the Athabasca series are proposed.

TL;DR: In this paper, the authors describe the experimental techniques used, to develop low-cost, calcium catalysts for the steam gasification of coal and present the results obtained in this work.

TL;DR: The relation between the rate of CO2 gasification and the properties of coal is quantitatively explained in this paper, where the specific gravity separation method is used to prepare coals which possess almost the same reflectance, but contain different amounts of inertinite and ash.

TL;DR: In this article, the authors used thermogravimetric and differential scanning calorimetry to examine, in nitrogen, four sewage sludges at modest heating rates and derived a mechanism consisting of two independent reactions for an undigested sludge.

TL;DR: In this article, a set of 21 vitrinite concentrates have been characterized by FTIR and the variation in values of the extinction coefficients for aromatic and aliphatic CH bands are determined as a function of assumed values for the extinction coefficient of the OH bands.

TL;DR: In this paper, diffuse reflectance Fourier transform infrared spectrometers have been used to measure coal in-situ, and the degree of oxidation of coals, both for natural oxidation in the seam and for laboratory oxidation, can be determined from the second derivative of these spectra.

TL;DR: In this paper, a typical hydrogen-donor system was studied for the hydrogenation of naphthalene to tetralin using activated red mud as a catalyst, and the most active catalyst, prepared by adding 20 wt% of Ti0 2 to the red mud, followed by acid digestion and re-precipitation, resulted in a 58% conversion of NPH.

TL;DR: The first detailed chemical analysis of an Australian shale oil was carried out by as discussed by the authors using gas chromatography-mass spectrometry (GC-MS) to identify 500 compounds, including homologous series of straight-chain alkanes, 1-, 2-and 3-alkenes, nitriles, methyl ketones, amides and substituted cyclopentanes, cyclohexanes, benzenes, naphthalenes, pyridines and quinolines.

TL;DR: In this article, the percentage of aromatic carbon in three representative solid coal samples and one pitch sample have been determined by three different n.m. techniques: cross-polarization/magic-angle spinning (CP/MAS), magnetization curves fitted to a theoretical expression and the fit parameters used to calculate the proportion of aromatic carbons.

TL;DR: In this paper, the effects of minerals on product compositions from rapid pyrolysis of a Pittsburgh Seam bituminous coal were investigated, and the results were similar to demineralized coal results under all conditions.

TL;DR: In this paper, the design of a compact, environmentally acceptable, carbon dioxide-diluted, coal-oxygen-fired power plant is described, where the oxygen for combustion is separated in an air liquefaction plant and the effluent nitrogen is available for use in oil well production.

TL;DR: In this paper, an alternative method for the proximate analysis of coals and cokes using a thermobalance is described, which measures water content, volatile matter, fixed carbon and ash residue and takes

TL;DR: In this paper, the authors predict the behavior of alkalis in the furnace gases of pulverized-coal-fired boilers, and show that a large proportion of the volatile sodium in the coal reacts with silica or silicate fly ash and forms a low viscosity surface layer of sodium silicate on the ash which, depending on its thickness, may enhance retention of the ash particles impinging on boiler tubes.

TL;DR: In this article, a model of pericondensed aromatic rings was used to estimate the average number of condensed polynuclear rings in an average molecule in anthracite coal.

TL;DR: In this article, the authors measured the rates of evolution of C 0 2, CO, H 2, CH 4 and the C 2 and C 3 hydrocarbons during pyrolysis of seven Colorado oil shales.

TL;DR: In this article, a triple-path coupled burn-off adsorption site was proposed to describe the oxidation of coal in a fixed-bed reactor under mild conditions, i.e. conditions which are useful in pretreatment for gasification.

TL;DR: In this paper, high-volatile bituminous coal and coal saturated with fully deuterated solvents, were studied using the 1 H n.m.r. pulse technique.

TL;DR: In this article, the formation of sodium silicates in reactions between silica particles and a synthetic furnace gas containing sodium, chlorine, sulphur and water vapour was investigated, and it was shown that in large pulverized-coal-fired boilers, in the presence of alkali-ash reactions, the formation can be predicted by thermodynamic considerations.

TL;DR: In this article, the chemical structure and hydroliquefaction characteristics of oxygen-rich Yallourn brown coal were investigated, and the structural parameters (fa, f' a, and H aru C ar ) were derived from spectral data.

TL;DR: In this paper, a space filling model for low-, intermediate-, and high-rank coal molecules was constructed for experimentally determined parameters, such as chemical composition, aromaticity and ring index.

TL;DR: Asphaltenes which differ in their abilities to form water/oil emulsions were analysed by acidimetry, infrared and nuclear magnetic resonance spectroscopies as mentioned in this paper.

TL;DR: In this article, a number of ring alkyl-substituted phenols were investigated in the presence of a commercial Co-Mo-Al2O3 catalyst and the results indicate that the catalytically active site is stereochemically demanding.

TL;DR: In this paper, the results of magic-angle spinning (CP/MAS) nuclear magnetic resonance (n.m.r.) experiments are reported on two fusinites, three vitrinites, one micrinite, one sample of attrite, one exinite, resinite and one lignite.

TL;DR: In this article, the authors used 13C n.m.r. measurements of the organic carbon distribution of oil shales, before and after Fischer assaying, and for oil shale of different grades, geographic location, geologic ages and formations.

TL;DR: In this article, an electrically-heated grid was used to flash-pyrolys the bituminous coals, an anthracite and a lignite, with activation energies of 16 and 35 kJ mol −1.

TL;DR: In this paper, a total of 21 coal covering all ranks have been burned under a wide variety of conditions to ascertain the impact of coal properties on the fate of fuel nitrogen during combustion.

TL;DR: In this article, a model compound, guaiacol, is used for the study of the behavior of the carbon-oxygen bonds under thermolytic conditions, and the thermodynamic properties of the compound are studied in tetralin, naphthalene and without solvent under hydrogen or nitrogen pressure at 578-618 K.

TL;DR: In this article, experimental data for devolatilization of coal in sizes and at operating conditions pertinent to fluidized-bed combustors are examined, showing that the time for coal deformation is characteristic of a diffusion-limited situation.