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1.3. Structure of oil asphaltenes


Asphaltenes are the most high-molecular and the most difficult on element composition and a molecular structure an oil part. To asphaltenes traditionally carry the substances settling from oil at the big dilution by the lowest aliphatic solvents (alkanes С3-С7, petroleum aethers, etc.).
Thus, asphaltenes are defined from the point of view solventnoj classifications.
Asphaltenes play a paramount role in structuring of the VAT and cause stability of colloidal structure neftej. Therefore asphaltenes represent the major class of components of oil [25-28]. Asphaltenes define rheological behaviour of oil systems [27, 28], considerably influence extraction [29], transportation and processing neftej [25-28]. Extraction vysokoobvodnennyh and heavy neftej, especially sensitive to difficult behaviour asfaltenovoj phases [29] Recently grows.
The maintenance of asphaltenes in neftjah fluctuates in the range of 0,1-10 mas. %., and in native bitumens can reach 50 % of weights. Despite rather low maintenance of asphaltenes in neftjah (in comparison with hydrocarbons and resins) interest of researchers to chemistry of these high-molecular components owing to the objective reasons continuously increases. The certificate to that is discussion of results of studying of composition and a structure of molecules of asphaltenes, revealing of perspective directions of their processing and practical use at numerous forums and conferences.
The major, and to this day, the question on size of molecular weight of asphaltenes is debatable. More than 20th years are discussed order of magnitude of molecular weight of asphaltenes [30, 31]. If order of magnitude of molecular weight the problem of an establishment of the general communication between a molecular structure and physical properties of asphaltenes is at a loss is unknown at least.
According to all available information [31-34] the reasons of distinctions of sizes of molecular weights of asphaltenes estimated by various methods (from 200 to 20000 a.e.m are defined.). The Most real values of molecular weights yield methods of mass spectroscopy [35-37] and fluorescent depoljarizatsionnoj to spectroscopy [30, 31]. According to these methods the expert-faltenov makes value of molecular weight 500-1000 a.e.m.
Thus, asphaltenes not the huge molecules making a dispersive phase of oil systems, and so-called [34] monomeric units, combining in molecular aggregates.
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A source: Tagirzjanov, Marseilles Ilgisovich. ASPHALTENES VANADIJSODERZHASHCHIH neftej (on an example of oil objects of deposits of Tatarstan) the Dissertation on competition of a scientific degree of a Cand.Chem.Sci. Kazan - 2003. 2003

More on topic 1.3. Structure of oil asphaltenes:

  1. 1.3.1. Composition and structure polycyclic and alifaticheskihfragmentov structures of asphaltenes
  2. 3.1. Laws of interrelation of the maintenance vanadilovyh complexes with the maintenance of sulphur, asphaltenes and free radicals in neftjah and asphaltenes.
  3. Tagirzjanov, Marseilles Ilgisovich. ASPHALTENES VANADIJSODERZHASHCHIH neftej (on an example of oil objects of deposits of Tatarstan) the Dissertation on competition of a scientific degree of a Cand.Chem.Sci. Kazan -, 2003 2003
  4. 6.1. Degree of extraction of free stable radicals and vanadilovyh complexes asphaltenes from neftej
  5. 2.2.7 Technique of definition of maintenance VK and CP in neftjah and asphaltenes method EPR
  6. 5.2. Studying of interrelation of the maintenance vanadilovyh complexes isvobodnyh radicals in neftjah and asphaltenes
  7. Z.Strukturnye types of asphaltenes with the various maintenance of vanadium
  8. 6.2. Comparison of spectral characteristics of asphaltenes
  9. 6. STUKTURNYE FEATURES of ASPHALTENES neftej With the VARIOUS MAINTENANCE of VANADIUM
  10. 4.2. Fenalenilnyj a radical as a part of heavy resin of pyrolysis iosobennosti technogenic asphaltenes
  11. 1.2.2. Features of the organisation of high-molecular components of oil systems
  12. 1.1.3 Adsorbed residual oil
  13. 1.1.2 Is capillary-jammed residual oil