Published in Solid Fuel Chemistry
AbstractExperimental results on the kinetics of hydrogenation of a wide fraction of coal tar (bp 230–300°C) in the presence of a Fe3O4 nanocatalyst are presented. The rate constants, overall rate constants, and activation energies were calculated. It was established that the conversion of preasphaltenes into asphaltenes is the rate-limiting stage o...
Published in Solid Fuel Chemistry
AbstractClose-packed materials (CPMs) were prepared by pressing dispersed carbon powders with various physicochemical properties. It was found that a maximum density of CPMs based on dispersed carbon was achieved when a sample was held under pressure for 2 to 3 h, and the complete degradation of secondary structures occurred in the low-structure sa...
Published in Solid Fuel Chemistry
AbstractThe effect of alkaline extraction parameters on the yield, biological activity, and functional group composition of the humic acids (HAs) of brown coals was investigated. It was found that the functional group composition of the HAs can be intentionally affected by varying alkaline extraction parameters (the amount of an alkali and the dura...
Published in Solid Fuel Chemistry
AbstractThe oxidation of lignite and bituminous coal modified with an activating additive of Fe(NO3)2 (5 wt %) was investigated. Iron nitrate was applied by incipient wetness impregnation with the preliminary dissolution of Fe(NO3)2 in a water–alcohol solution with the volume ratio C2H5OH : H2O = 50 : 50. The reactivity of the samples was studied b...
Published in Solid Fuel Chemistry
AbstractThe concentration levels of valuable (rare, rare-earth, noble, nonferrous, radioactive, etc.) metals in coals were studied for the preliminary assessment of their possible industrial importance. With consideration for the similarity of the composition of the mineral matrix of coal or coal ash to the trace-element composition of the industri...
Published in Solid Fuel Chemistry
AbstractThe effect of the conditions of mechanochemical peat acetylation with acetic anhydride on the concentration of bound acetyl groups and the solubility of the resulting products in acetone was studied. Highly substituted esterification products containing to 17.8% bound acetyl groups and soluble in acetone to 60% were obtained.
Published in Solid Fuel Chemistry
AbstractIt was established that a shift of equilibrium in the graphite–calcium oxide system toward the formation of calcium carbide can be observed at a temperature of 900°C due to the formation of a volatile substance—carbon monoxide. Upon the addition of anthracite, a maximum of calcium carbonate decomposition decreased from 813 to 780°C, and the...
Published in Solid Fuel Chemistry
AbstractThe necessary conditions and integral characteristics of the ignition and subsequent combustion of mixed fuels prepared on the basis of peat, crude oil, and water were studied. Fuel mixtures were burned in the form of a layer (a weighed sample), slurry droplets, or pellets in a model combustion chamber at a temperature of 300–900°C. The res...
Published in Solid Fuel Chemistry
AbstractA method for the synthesis of metal–carbon nanocomposites in which metal-centered particles of the core–graphite-like shell type are distributed in the bulk of an amorphous sp2-carbon matrix is proposed. Polyvinyl chloride (PVC) was used as a carbon matrix precursor. The synthesis procedure included the following stages: The dehydrochlorina...
Published in Solid Fuel Chemistry
AbstractThe thermal decomposition of peat in a drop tube furnace was studied under conditions typical of the low-temperature combustion chambers of industrial heat-generating plants, and the combustion of peat charcoal was examined on a thermogravimetric analyzer with dynamic heating. It was established that the thermal properties of peat are well ...
