Showing papers in "Fuel in 1979"

TL;DR: In this article, the devolatilization behavior of coarse-ground Loy Yang brown coal was investigated under rapid heating conditions using a small-scale fluidized-bed pyrolyser.

TL;DR: The chemical structure of two extracts prepared by supercritical extraction of low-rank coals with toluene, with and without hydrogen, have been determined using solvent and Chromatographic fractionation followed by ultimate analysis, 1 H nuclear magnetic resonance (n.m.r.) spectroscopy, molecular weight and OH measurements as discussed by the authors.

TL;DR: In this article, the authors used high-power proton decoupling, cross polarization and magic-angle spinning to obtain the carbon distribution between aromatic and non-aromatic structures in coal samples.

TL;DR: In this article, a raw lignite has been treated with HCl and HF to demineralize it and to increase its carboxyl content prior to exchanging selected cations with the hydrogen on the Carboxyl groups.

TL;DR: In this paper, a new selective alkylation procedure was developed which converted polar hydroxyls into relatively non-polar ethers and esters, and has been successfully tested on a bituminous and sub-bituminous coal.

TL;DR: In this article, coal was converted by methanol/KOH systems to a product which was extractable by pyridine fully, and 15-25% of the mixture was enriched in hydrogen relative to the starting coal.

TL;DR: In this paper, petrographic methods and coking tests were used to quantify the effects of weathered coal on coking properties and coke quality, and the results showed that the presence of coal weathered in coal mixes causes a decrease in coke stability and rate.

TL;DR: The effect of low-temperature pyrolysis (up to 300 °C) on acid groups of two low-rank coals (a brown coal from Victoria, Australia, and a lignite from Texas, U.S.A.) has been studied for samples in both acid and cation forms.

TL;DR: In this paper, the authors used various amounts of boron and several kinds of carbon in an attempt to reveal whether the BORON exhibits other kinds of catalytic effect.

TL;DR: In this article, the authors measured the reactivity of seventeen 40 × 100 mesh (U.S.) coals charred to 1000 °C in 0.1 MPa of a N2H2O mixture containing water vapour at a partial pressure of 2.27 kPa.

TL;DR: In this paper, a new method is described for determining the mineral-matter content of coals, based on low-temperature ashing in an oxygen plasma, which is unsuitable for use with HVC coals from Western provinces of the USA or with lignites and subbituminous coals.

TL;DR: In this paper, the pyrolysis of a Yallourn brown coal in the acid form and several different cation forms has been studied at temperatures up to 900 °C, in regard to the decomposition of acid groups, the relation between oxygen products evolved and these groups, and the fate of cations.

TL;DR: Yallourn brown coal was oxidized with pure molecular oxygen at temperatures of 35 and 70 °C until, after about 45 days, no further gain in mass occurred as mentioned in this paper, despite the loss of considerable quantities of carbon and hydrogen from the coal as carbon dioxide, carbon monoxide and water.

TL;DR: In this article, coal is consumed within an aqueous electrolyte to produce gaseous oxides of carbon at the anode and hydrogen at the cathode, and an abrupt and reproducible jump in potential is observed which suggests at least two different mechanisms for the overall process.

TL;DR: In this article, the authors studied the self-heating tendency of Australian coals and chars and found that the rate of oxidation increases with increasing moisture content and decreases with increasing carbonization temperature of the parent coal and with the extent of the char's weathering.

TL;DR: Athabasca asphaltene has been pyrolysed at 350, 500 and 800 °C, and the condensible volatile products analysed using gas Chromatographic and mass spectrometric procedures as discussed by the authors.

TL;DR: For four Kentucky coals, a comparison was made between pore volume distribution evaluated from CO2 adsorption isotherms calculated from the Cranston-Inkley method and the Medek method.

TL;DR: In this paper, tetralin was heated for various periods at temperatures between 300 and 450 °C without hydrogen or coal, and the products were analysed by capillary chromatography.

TL;DR: In this paper, the role of solvent in coal liquefaction of different rank was studied with a variety of solvents at 370-390 °C under nitrogen in order to find a suitable solvent for the highest yields of liquidation.

TL;DR: In this article, a mathematical model of the self-heating reaction of coal or char in bulk has been developed, which takes into account a local oxidation reaction which depends on temperature and the concentrations of unreacted and reacted oxygen.

TL;DR: In this article, the effects of different coal ashes on the gasification kinetics of graphite were compared, and a parallel study was made by adding lignite ash to a coal of low reactivity.

TL;DR: In this paper, the basic components contained in a coal liquefaction product obtained from the Wilsonville, Alabama coal-liquefaction pilot plant were examined by means of capillary-column Chromatographic-mass spectroscopy.

TL;DR: The surface area changes in chars are markedly dependent upon whether the acid treatment is given to the coal precursor prior to charring or to the char produced from the raw coal.

TL;DR: In this article, the pyrolysis of tetralin has been studied at 500 °C and the products resulting from the decomposition of 1-13 C-tetralin were analysed by 13 C n.m.r. spectroscopy.

TL;DR: In this article, the effects of alkaline earths on the steam gasification of two coal chars, one of low and one of high intrinsic reactivity, were evaluated gravimetrically.

TL;DR: In this paper, properties and compound types were examined in detail for tar-sand bitumens representative of four major deposits in Utah and Alberta, and methods for bitumen extraction, separation, and compound type (functional group) analysis were presented.

TL;DR: In this paper, coal devolatilization studies were carried out with a pressurized laboratory fluidized-bed reactor, where coal was injected into a hot bed of char; the off-gas was sampled and analyzed; and the char and agglomerates produced were examined and characterized.

TL;DR: In this article, the authors summarize the current state of knowledge of the mechanisms of these interactions possible mechanisms of interactions are summarized, kinetic and chemical structural aspects of reactions are outlined, the importance is mentioned of the formation of liquid phases enabling anisotropic optical textures in modified cokes to be created, and the industrial relevance of its possible development is discussed.