Coke and Chemistry最新文献

In the first article of this series, the influence of the preparation and heat treatment of heavy tar on the yield, softening point, degree of coking, and density of petroleum pitch was considered [1]. In the present article, the influence of the preparation of heavy pyrolysis tar on the group composition of the produced is studied. The influence of the group components on the coking properties and softening point of the pitch is considered. By adjusting the production conditions, the group composition of the pitch may be regulated, and pitch of specified quality may be obtained.

The morphology, structure, and mineral composition of carbonized industrial samples are studied by scanning electron microscopy. According to the results, the carbonized samples include particles of different sizes, which are covered by a layer of organic mass containing oxygen. Disperse amorphous calcium carbonate is also present, as confirmed by the decrease in oxygen content at the surface of the particles after heating the sample to 800°C in an inert atmosphere. The mineral component of the carbonized sample is found to contain the elements Ca and Mg, which are typical of lignite. The microstructure established for the sample is also typical of carbonized lignite.

Humic substances—humic acid, hymatomelanic acid, humus acid, and fulvic acid—have been isolated from lignite mined in the Tisulsky deposit of Kansk-Achinsk Basin. The samples obtained are characterized by means of technical and elemental analysis. The content of functional groups is determined by potentiometric titration. For all the acids, the content of carboxyl and hydroxyl groups in the humic substances may be ranked as follows: Ar–OH > Ar–COOH > Alk–COOH.

A method is proposed for the heat treatment of solid carbon residue from the pyrolysis of rubber products in an oxygen-free atmosphere, so as to improve its quality and expand its practical applications. The initial residue and the heat-treated residue are studied by electron microscopy, IR spectroscopy, and X-ray phase analysis.

Preliminary data are gathered regarding the effectiveness of various reagents on the basicity of Kaa-Khem coal in laboratory flotation.

The following coal samples are compared: Kansk-Achinsk lignite from the Kaichasky-1 and Berezovsky mines; and long-flame (bituminous) coal from the Pervomaisky mine in the Kuznetsk Basin. Their composition and results of their technical analysis, elemental analysis, and petrography are presented. In all cases, the ash content is low (5.0–8.0%), as is the sulfur content (0.2–0.4%). In the mineral component of the lignite samples, the main elements are calcium, silicon, and sulfur; for the bituminous coal, they are silicon, aluminum, and iron. The samples are complex mixtures of macerals in the vitrinite, semivitrinite, inertinite, and liptinite groups. For all the coal samples, the reflectogram is free of discontinuities; the petrographic nonuniformity is minimal, with a predominance of the vitrinite group. The goal of the research is to select the optimal sample for the production of specialized activated coal additives in the thermal hydrocracking of heavy oil refining residues (tars). Such additives must meet requirements regarding the sulfur content, the content of the ash, its composition, and the porosity of the structure.

The aluminum content in coal wastes in the Kemerovo region of the Kuznetsk Basin is investigated. The possibility of using such waste to extract aluminum concentrate by acidic leaching using sulfuric acid and nitric acid is assessed. Complete aluminum extraction in one processing cycle is impossible, but around 96% extraction is possible by successive leaching. The content of aluminum oxide in the concentrate is 84.5%.