Structure of asphaltenes occurring in oils of different chemical nature
The relevance of the work is caused by the need to obtain and generalize information on composition and structure of asphaltene components in oils of different chemical nature, since the features of structural characteristics of asphaltenes have a significant effect on the depth of their thermal des...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | Russian |
| Published: |
Tomsk Polytechnic University
2018-10-01
|
| Series: | Известия Томского политехнического университета: Инжиниринг георесурсов |
| Subjects: | |
| Online Access: | http://izvestiya.tpu.ru/archive/article/view/2089 |
| Summary: | The relevance of the work is caused by the need to obtain and generalize information on composition and structure of asphaltene components in oils of different chemical nature, since the features of structural characteristics of asphaltenes have a significant effect on the depth of their thermal destruction. Recently the works in this area are of particular importance due to the steady increase of heavy oils, which differ from traditional oils with high contents of asphaltenes, in compositions of explored and recoverable reserves. The aim of the research is the comparative analysis of structural-group compositions of asphaltenes in typical methane-naphthenic oil and heavy oil of a naphthenic-aromatic base, the molecular composition of structural fragments bonded in molecules of their asphaltene components through sulfide and ether bridges, and covalently unbonded compounds. Research methods: elemental analysis, cryoscopy in benzene, extraction, liquid-adsorption chromatography, selective chemical destruction of sulfide and ether bonds, 1 H NMR spectroscopy, structural-group analysis, chromatography-mass spectrometry. Results. The authors have carried out the comparative analysis of composition and structure of asphaltene components in methanenaphthenic and naphthenic-aromatic oils and identified the similarities and differences in their structural-group compositions, compositions of fragments bonded in asphaltene molecules via ether and sulfide bridges and in the compositions of compounds occluded by macromolecules of asphaltene substances. Using the methods of mild chemical destruction of sulfide and ether bonds, n-alkanes, cyclohexanes, steranes, hopanes, n-alkylbenzenes and n-alkyltoluenes were considered the most common fragments of asphaltene macromolecules in methane-naphthenic and naphthenic-aromatic types of oils. A peculiarity of asphaltene molecules in methane-naphthenic oil is the presence of alkenes and unsaturated steranes in composition of their structural fragments, while that in naphthenic-aromatic oil - pregnanes, cheilanthanes, thiophenic compounds and ethyl esters of alkane acids. |
|---|---|
| ISSN: | 2500-1019 2413-1830 |