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The use of charcoal (CC) for various industries was analysed; the modern ideas about the factors influencing the process of obtaining CC were considered. The effect of raw materials nature (wood or agricultural wastes) and their characteristics (size, physical properties, chemical composition), as well as carbonization temperature, heating rate, oxygen level and pressure on the yield and quality of CC was described. The existing technologies for charcoal production were analyzed; they were classified according to the type of heating initiation and temperature maintenance during the carbonization process. The Lambiotte, DPC and Carbonex technologies were considered.

The conditions providing proceeding of the reactions between pyrite sulphur of medium-metamorphized coal and air-steam mixture in the kinetic area have been found. Experimental-statistical mathematical model has been designed. The optimal factors of mediumcoalificated coal oxidative desulphurization have been determined on its basis. Under optimal conditions two samples of coking coal have been desulphurized. These samples will be used as components of the coal charge in the production of special types of coke.

In this paper, the desulphurisation of high sulphur low-rank coal is proposed as a raw material for pulverised coal injection technology. Therefore, the influence of oxidant linear velocity and the size of the coal grain was investigated in a fluidised bed. The hydrodynamic parameters of the fluidised bed including: porosity, Sherwood criterion (diffusion Nusselt number), and mass transfer coefficient (external surface) were calculated. Furthermore, the study examined the effects of intensity and efficiency on the desulphurised coal properties; organic matter, ash, and volatile matter contents. The key changes during the conversion of pyritic sulphur and coal organic matter were subsequently examined. The results showed that the sulphur content (S t d 3.16 wt%) of the low-rank coal, was transformed to (S t d B 1.5 wt%) after desulfurization. Other enhanced properties were: V daf B 38.0 wt%; A d B 10.0 wt%, now suitable for pulverised coal injection technology.

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In the article the chemistry of the noncatalytic oxidative desulfurization process of distillate oil fractions is analyzed. The study involves the characteristics of high-sulfur straight-run diesel fraction of narrow composition (593–623 K) before and after oxidation by air at 453–493 K and a pressure of 3.0 MPa. The composition of sulfur compounds in the raw material fraction was determined. It is shown that straight-run fractions of raw materials may also contain sulfoxides, which are products of oxidation of organosulfur compounds and are formed during storage of petroleum products. On the basis of IR spectroscopic studies of raw materials, oxidized products and model mixtures, the transformation depth of fr. 593–623 K sulfur compounds, which are distributed in the form of sulfones and sulfoxides in solid and liquid oxidation products, and partially remain in the purified fuel, was analyzed in the above-mentioned process.