Bitumen fractions

Gray, M. R., and McCaffrey, W. C., Role of Chain Reactions and Olefin Formation in Cracking, Hydroconversion, and Coking of Petroleum and Bitumen Fractions. Energy Fuels, 2002. 16(3) pp. 756-66. 

Bitumen Fraction Off Saturates Total Distillates Heavy Saturates Total Distillates Heavy Saturates... 

Extraction of tar sands with benzene or toluene yields a bitumen fraction and a mineral fraction. Further treatment of the bitumen with heptane or n-pentane yields asphaltenes and petrolene, which are the insoluble and soluble fractions, respectively. Depending on the source, these fractions contain varying amounts of vanadium (117,118). 

The bitumen fraction obtained from the first benzene/methanol Soxhlet extraction accounts for 11.8, 16.1, and 13.5 wt% of the total organics in the original shales for the 184, 129, and... 

The paraffinic carbon composition is similar for both groups of acid/ether extracted organics as is the presence of mono- and diaromatic compounds. No significant pH effects are observed, although the basic HC1 extract has a lower aromatic content than either the pH 1 or 6.5 fraction. The NMR data for the first bitumen fraction indicate that it is also predominantly paraffinic, in agreement with the earlier results of Spiro. (2 )... 

Extracts of organic material were also obtained with other fluids as indicated in Table II. Although no detailed analyses of these extracts were obtained, it would appear that these extracts are of the bitumen fraction as expected. 

A variety of parameters are used to assess organic matter sotrrces. Btrlk parameters have the advantage that they are representative of total organic matter, whereas molectrlar parameters address only part of the extractable organic matter, which in turn is only a small portion of total organic matter. Some successfirl applications of molectrlar parameters show that the small bitumen fraction may be representative of the total, but there are many other examples where this is not the case. On the other hand, oxidation of marine organic... 

The correlation of the carbon isotope composition (<5 C) of the oil and bitumen fractions of all eventual source rock conditions , in view of the large variety of the latter, allows us to point out the sources of the hydrocarbons which supplied the one or other reservoir and thereby to better direct the prospecting activities. 

Figure 15.23 shows changes in bitumen fractional contents after PetroBeam processing. The feedstock had density of 0.9781 g/cm and kinematic viscosity of 2912 cSt at 40°C. The C/H ratio for the bitumen with completely removed water was 8.7. 

Figure 15.23 demonstrates considerable improvement in bitumen fractional contents after PetroBeam processing. The aforementioned examples show that PetroBeam process of low-temperature radiation cracking provides efficient upgrading of any type of high-viscous oil feedstock. 

The heavier oils and bitumen fractions now contained O-H and C-O bonds to show the presence of oxygenated compoxmds. These groups were initially absent from the oils when they were just produced, to show that the bituminous oils were unstable and consequently very reactive. They picked up oxygen from the atmosphere during storage. The lighter oil fractions still did not contain oxygen. 

The thermal chemistry of heavy oils and bitumen is extremely complicated because of wide variations in chemical compositions. The most refractory components in petroleum feedstocks are asphaltenes, which contribute the most to coke formation dining thermal cracking. Next to asphaltenes, resins and large aromatics also contribute to coke. To investigate the effect of these three heavy oil components on the mesophase induction period, Athabasca bitumen fractions containing varying amounts of asphaltenes (obtained by supercritical fluid extraction) and Venezuelan heavy... 

Rahuni, P. Dettman, H. Gentzis, T. Chung, K. Nowlan, V. Upgrading chemistry of Athabasca bitumen fractions derived by super critical fluid extraction. Presented at the 47 CSChE conference, Edmonton, Alberta, Canada, October 5-8,1997. 

Rahimi, P. Gentzis, T. Fairbridge, C. Interaction of clay additives with mesophase formed during thermal treatment of soUd-lree Athabasca bitumen fraction. Energy Fuels, 1999,13, 817. 

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