Thermal transformations of high-molecular-mass-components of heavy petroleum residues

Kopytov, M. A.; Головко, А. К.; Kirik, N. P.; Anshits, A. G.

doi:10.1134/s0965544113010076

Cited by 23 publications

(10 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The use of process flow diagrams for separation and deep purification of FSs concentrates, which include granulometric, hydrodynamic, dry, and wet magnetic separation stages, enables classification of four known ash types, sialic (S), ferrisialic (FS), ferricalsialic (FCS), and calsialic (CS), into narrow FSs fractions of constant composition with the Fe 2 O 3 content in a range of 30–92 wt % and globule size in a range of 50–250 μm , and with reproducible magnetic properties. , The produced FSs fractions have the common composition–morphology–microstructure relationship for iron-containing phases, which, in turn, suggests their application areas as functional materials. FSs of constant composition can be used as effective catalysts for deep oxidation, oxidative coupling of methane, − thermolysis of heavy oils and oil residues, and magnetic carriers for affinity sorbents in protein separation …”

Section: Introductionmentioning

confidence: 99%

“…27,28 The produced FSs fractions have the common composition−morphology−microstructure relationship for iron-containing phases, 25 which, in turn, suggests their application areas as functional materials. FSs of constant composition can be used as effective catalysts for deep oxidation, 29 oxidative coupling of methane, 30−32 thermolysis of heavy oils and oil residues, 33 and magnetic carriers for affinity sorbents in protein separation. 34 The differences in chemical and phase compositions and functional properties of FSs from different ashes are explained by the presence of several morphological globule types with their different contents in narrow fractions.…”

Section: ■ Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Composition, Structure, and Formation Routes of Blocklike Ferrospheres Separated from Coal and Lignite Fly Ashes

et al. 2020

View full text Add to dashboard Cite

The structure–composition relationship of blocklike ferrospheres (FSs) isolated from fly ash from the coal and lignite combustion has been studied systematically by scanning electron microscopy and energy dispersive X-ray spectroscopy. Groups of globules for which the gross composition of polished sections corresponds to the general equations for the relationship of the concentrations SiO2 = f(Al2O3) and CaO = f(SiO2) are highlighted from FSs of two series. It is shown that blocklike FSs are formed during the sequential transformation of dispersed products of thermal conversion of mineral precursor associates: pyrite, quartz, and Ca, Al-humates in the case of brown coal; and pyrite, siderite, quartz, and calcite in the case of coal. Anorthite is the aluminosilicate precursor of blocklike FSs of both series. The dependence CaO = f(SiO2) that reflects the influence of glass-forming components reveals six groups of FSs. An analysis of SEM images of polished globule sections demonstrates that an increase in the concentration of glass-forming components in all groups is accompanied by gradual changes in the structure of globules, from a large blocklike type to a fine crystalline type with a high glass-phase content. The size and shape of crystallites are controlled by the size of a local melt area where the total concentration of spinel-forming oxides exceeds 85 wt %. An increase in the glass-phase concentration and a decrease in the crystallite size in globules with FeO ≤ 46–50 wt % are explained by expansion of the segregation region in the FeO–Fe2O3–SiO2 system as the oxidation potential rises.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%

Composition, Structure, and Formation Routes of Blocklike Ferrospheres Separated from Coal and Lignite Fly Ashes

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The most detailed information about the structure of molecules of resins and asphaltenes could be obtained using the methods of directed cleavage of their macromolecules into identifiable moieties that, however, can store information about their original structure and in some cases about the form of connectivity. These methods include thermal destruction of RAS within a wide temperature range with a detailed analysis of the products obtained. − However, under high-temperature conditions, processes may occur that result in the formation of secondary products, whose presence in the reaction mixture makes it difficult to obtain reliable information about the chemical nature of RAS. ,, Hence, works aimed at the detailed study of the composition and structure of RAS and focused on the selective chemical destruction of RAS macromolecules are growing in number. ,− , Thus, chemical degradation allows the establishment of the details of the “blocks” involved in the construction of macromolecules of resins and asphaltenes, in particular, to obtain data on the presence of C–S, C–O bridges in their structure and to determine the qualitative composition of the “bound” moieties. It has been shown that the main “sulfur- and ether-bound” compounds in RAS molecules are saturated and aromatic hydrocarbons (HCs) and sulfur- and oxygen-containing structures. ,,− , No bound nitrogen-containing compounds have been identified in the building blocks of molecules of resins and asphaltenes.…”

Section: Introductionmentioning

confidence: 99%

Resins and Asphaltenes of Light and Heavy Oils: Their Composition and Structure

et al. 2019

View full text Add to dashboard Cite

The complex of physicochemical methods of analysis (elemental analysis, cryoscopy in benzene, IR and 1H NMR spectroscopies, structural group analysis, gas chromatography–mass spectrometry, and selective chemical cleavage of sulfide and ether bonds) is used to comparatively characterize resins and asphaltenes of light and heavy oils. Attention is paid to the study of their structural group composition and the composition of moieties bound in molecules of resin–asphaltene substances (RAS) through ether and sulfide bridges, as well as the composition of compounds occluded by asphaltene molecules and nitrogen bases of resins. It is found that resins and asphaltenes of the heavy oil are characterized by higher average molecular masses and large overall sizes of mean molecules, due to the increased content of aromatic cycles in the naphthenic–aromatic system. The similar sets of linear and branched alkanes, alkylcyclopentanes, alkylcyclohexanes, steranes, mono- and disubstituted alkylbenzenes, and dibenzothiophenes identified in occluded compounds and products of chemolysis of resins and asphaltenes under study suggest the presence of most of these compounds as structural fragments in RAS molecules of light and heavy crude oils under study. Alkyl-substituted quinolines and benzoquinolines are identified in the nitrogen bases of resins. The feature of the light oil is the presence of “sulfur-bound” alkenes and polycycloalkenes in the structure of its asphaltenes. The findings expand our understanding of the structure of petroleum resins and asphaltenes. They can be used to simulate their structure in developing new controlled methods for processing hydrocarbon feedstock.

show abstract

“…The products of such thermo-destructive processes are gases, liquids, substances insoluble in a hydrocarbon medium, and organic solvents. An analysis of the gaseous and liquid products of the destruction of asphaltene molecules revealed that their structural blocks contain normal and branched alkanes, monocyclic and polycyclic naphthenes and arenes, and benzologues of thiophene, furan, and indole. ,− However, some data that have been obtained using this approach may be unreliable, because of the possible occurrence of secondary processes of thermal destruction and coke formation at high temperatures. ,, Changes in the nature and mechanism of thermal destruction processes are possible in the flow of supercritical fluids.…”

Section: Introductionmentioning

confidence: 99%

Characteristics of Products of Thermal Decomposition of Heavy Oil Asphaltenes under Supercritical Conditions

et al. 2020

View full text Add to dashboard Cite

This paper presents the results of a comparative study of the composition of asphaltenes of two heavy oils and liquid products of their conversion in a supercritical hexane (SCH) stream. Using elemental analysis, cryoscopy in benzene, infrared and 1 H nuclear magnetic resonance spectroscopy, structural group analysis and chromatography, and mass spectrometry, the secondary asphaltenes, the resulted resins and oils, and concentrations of high-molecular-weight nitrogen bases isolated from maltene fractions of thermolysates are characterized. It is shown that the molecular mass of secondary asphaltenes increases as a result of SCH conversion, while the molecular mass of resins decreases, compared to the initial samples. This is due to an increase in the number of structural blocks in mean molecules of secondary asphaltenes and a decrease in their number in mean resin molecules. In both cases, the structural blocks become more compact, because of the decrease in the total number of rings, mainly naphthenic. The structural fragments of the molecules of asphaltenes of both oils are normal alkanes, alkenes, alkyl-substituted monocyclic, tetracyclic, and pentacyclic naphthenes, which are similar in the molecular mass distribution, including unsaturated, monocyclic, bicyclic, tricyclic, tetracyclic, pentacyclic, and hexacyclic aromatic hydrocarbons, benzothiophenes, dibenzothiophenes, naphthobenzothiophenes, and carbazoles. Some of these compounds can be bound in asphaltene molecules via methylene, ether, and sulfide bridges. Among the nitrogen bases of asphaltenes, C 11 −C 15 alkylquinolines, C 15 −C 17 benzoquinolines, C 18 dibenzoquinolines, and C 16 H 33 NO, C 18 H 35 NO, C 18 H 37 NO aliphatic amides are identified. Their presence in the composition of asphaltene structures is most likely associated with the participation of high-molecular-weight nitrogen bases in intermolecular interactions, which are due to the structural similarity of their molecules with asphaltene molecules.

show abstract

Thermal transformations of high-molecular-mass-components of heavy petroleum residues

Cited by 23 publications

References 2 publications

Composition, Structure, and Formation Routes of Blocklike Ferrospheres Separated from Coal and Lignite Fly Ashes

Composition, Structure, and Formation Routes of Blocklike Ferrospheres Separated from Coal and Lignite Fly Ashes

Resins and Asphaltenes of Light and Heavy Oils: Their Composition and Structure

Characteristics of Products of Thermal Decomposition of Heavy Oil Asphaltenes under Supercritical Conditions

Contact Info

Product

Resources

About