Solid Fuel Chemistry最新文献

The composition of biomarkers of the Upper Jurassic rocks in the Vostochno-Payduginskaya exploration well of the section of the Maryanovskaya and Naunaksk formations was investigated. The conditions of organic matter (OM) sedimentation were characterized based on data on the hydrocarbon composition, namely, the distribution of normal and isoprenoid alkanes, phenanthrenes, steranes, hopanes, and alicyclic and aromatic hydrocarbons. It was found out that OM was deposited throughout the section under study under oxidizing conditions. The sediments of the Naunaksk formation were formed in a shallow basin uncontaminated with hydrogen sulfide, while the OM of the Maryanovsk formation was formed in a lacustrine environment. The presence of low concentrations of gammacerane in the Maryanovsk formation and the lower parts of the Naunaksk formation indicated weakly saline waters of the sedimentation basin in this period. The participation of higher plants in the formation of the OM composition of the Naunaksk rocks was evidenced by high concentrations of cadalene and retene and the presence of simonellite and C₂₅ and C₂₇ n‑alkanes.

The influence of the duration of thermal action on the composition of cracking products of resins, asphaltenes, and their mixtures isolated from methane heavy crude oil of Zyuzeevskoye oil field was studied. Cracking was performed in a closed reactor at 450^оС for 60, 90, and 120 min. Data on the mass balance of the process and the composition of hydrocarbons and sulfur-containing compounds in the cracking products were obtained. It was shown that the yield of coke increased with the process duration in the cracking of every studied material. The joint presence of resins and asphaltenes in a mixture changed the direction of thermal transformations of these components in the cracking process.

The results of laboratory tests of an acidic oil-displacing composition based on a deep eutectic solvent (DES) are presented. The dissolving ability of the composition in relation to a carbonate reservoir rock was determined, and corrosion activity toward St3 steel was studied. Filtration tests demonstrated the high oil-displacing efficiency of the composition due to the equalization of filtration flows, increased formation sweep, and high oil-displacing ability.

A comparative analysis of changes in the microbiological and chemical composition of water and peat in the drained and fire-event areas of the Bakchar bog (the northeastern part of the Great Vasyugan Mire) was performed during the growing season of 2022. It was revealed that the fire effect persists in the upper layer (up to 50 cm) of the post-pyrogenic area even 6 years after the fire. It manifests itself in a disruption of the seasonal dynamics of the content of a number of components (O₂, CO₂, ({text{NH}}_{4}^{ + }), ({text{NO}}_{3}^{ - })), and in the size variance of different physiological microflora groups: ammonifying, pedotrophic, oligotrophic, hydrocarbon-oxidizing, cellulose-destructing, denitrifying, and sulfate-reducing. In addition, the correlations between the analyzed microbiological and physico-chemical parameters differ for drained and post-pyrogenic areas, which suggests the long-term pyrogenic effect on the processes of accumulation and destruction of organic matter.

Various conditions for the cracking of atmospheric residue from the Novokuibyshevsk Oil Refinery were considered and analyzed. Optimal conditions for the cracking of the atmospheric residue were found (a temperature of 450ºС and duration of 30 min), under which an additional 51.8 wt % of light fractions was formed due to the destruction of 31.3 wt % of resin–asphaltene components. The compaction products formed upon cracking were studied. Two fractions of asphaltenes (A1 and A2) from the feedstock and isolated from liquid cracking products were studied using structural group analysis. It was found that the duration of atmospheric residue cracking had an impact on the formation of secondary asphaltenes.

The composition of the products of cracking of oil shale (OS) from the Kashpirskoe deposit and kerogen isolated from it has been studied. The influence of OS mineral components on the material balance and qualitative composition of cracking products was shown. It was found that the amount of gaseous and solid products in kerogen cracking products decreased, and the yield of liquid products increased. The removal of mineral components from OS led to an increase in the oil content and a decrease in asphaltenes in liquid cracking products; the resin content changed slightly, and the yield of light fractions increased. The effects of mineral components on the structural-group characteristics of resins and asphaltenes in liquid cracking products were determined. The absence of mineral components led to an enlargement of resin molecules; on the contrary, asphaltene molecules became more compact.

The results of rheological measurements of a composition with two gelling components obtained in rotational mode and oscillation mode at different temperatures are presented. The kinetics of gel formation was characterized, and the strength of the formed structure was assessed. The gelation points and elastic moduli of the gel were determined.

The results of a study on the concentrations of rhenium and other valuable metals in oil shales from the Volga basin are presented. New data on the precise determination of Re, Co, Ni, Cu, Zn, U, and other metals by inductively coupled plasma mass spectrometry are presented. The test metal contents were compared with clarke values in carbonaceous shales. The association of metals (Mo, U, Co, Ni, Cu, Zn, Se, Ag, and Sb) with rhenium in oil shales was identified. The organic matter of oil shales acts as a concentrator of rhenium and, apparently, Mo and U. The preferred petrographic type of oil shales for the concentration of rhenium in them is the colloalginite–vitrinite–clay type. The rhenium and metal content of the Volga shales is compared with the concentrations of rhenium and a number of other valuable metals in the dictyonema shales of the Baltic sedimentary basin.

The literature sources containing information and description of experiments on the regeneration of activated carbons containing biologically active organic compounds on the surface and characteristics necessary for evaluating the effectiveness of regeneration are considered. It is shown that each regeneration method has its positive and negative sides.