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In this study, a small molecular viscosity reducer containing benzene ring was synthesized and evaluated its ability of dispersing asphaltenes and resins. It is helpful for introduction of polar groups to dispersing asphaltene. Benzene ring structure can make viscosity reducer molecules penetrate into the stacking structure of asphaltene and resin better. The long carbon chain in the molecule can interact with paraffin to change the crystalline state of paraffin and reduce the viscosity of heavy oil. Therefore, viscosity reducer has the function of reducing viscosity of heavy oil. And the smaller molecular weight can effectively avoid the phenomenon of viscosity increase in the process of viscosity reduction due to the excessive molecular weight of viscosity reducer. The experimental results show that VR‐1 has good viscosity reduction ability. And VR‐1 has excellent effect on the dispersion of asphaltene and the reduction of particle size. The mechanism of viscosity reduction is studied, and the results are consistent with the experimental results. [ABSTRACT FROM AUTHOR]

Heavy crude oil fractions which form the residues from fractional distillation are a significant proportion of current hydrocarbon reserves. However, processing residues for use as chemicals or fuels is hampered by the high polyaromatic content of this material. Selective reduction of aromaticity by targeted ring opening and the preservation of alkylated chain side groups are key requirements for the upgrading of alkylated polynuclear aromatic hydrocarbons (PAHs) to more easily processed and higher value molecules. In this study, a H2WO4 catalyst combined with H3PO4 and H2O2 oxidant is applied to the selective oxidation of PAHs containing different lengths of substituent alkylated chain, and different numbers of rings in the fused aromatic core. For a model substrate of 2-ethylnaphthalene, using traditional organic solvents, aliphatic carbon was oxidized more readily compared to aromatic carbon. However, it was found that the oxidation to desired products can be specifically controlled as the selectivity is directed by the choice of solvent, with reactions carried out in acetonitrile giving oxidation only in the aromatic region of the molecule. With larger polyaromatic molecules, a biphasic solvent system is used with Aliquat 336 as a phase transfer agent. Even for this more complex reaction system high conversion to the corresponding alkylated ring opened compounds was obtained. [ABSTRACT FROM AUTHOR]

The performance of both ebullated bed H-Oil vacuum residue (VR) hydrocracking and fluid catalytic cracking (FCC) of vacuum gas oils (VGO) is interrelated. The increase of H-Oil unit reaction temperature maximizes VR conversion and augments the aromaticity and density of the hydrocracked heavy oils. The FCC of VGO blends that contain more aromatic H-Oil VGOs is featured by a lower VGO conversion. It was found in this study that the reactivity of the H-Oil heavy oils depends on their molecular weight (T50) instead on their aromatics content as observed during catalytic cracking of straight run VGOs reported in other studies. [ABSTRACT FROM AUTHOR]

In this research, four different crude oils from Tatarstan oil fields with wide range of API gravities (from 16.6 to 32.5 °API) were used for hydrogen and carbon nuclear magnetic resonance spectroscopy (H NMR and C NMR) determinations. The hydrogen and carbon aromaticity factors were calculated by using the results of H NMR and C NMR spectroscopy results. The results show that the aromaticity factors were high for heavy crude oils. For predicting SARA fractions, the correlations were developed as a function of aromaticity factors. The developed correlations showed high accuracy for predicting SARA fractions for four crude oils. • The hydrogen and carbon aromaticity factors are increasing with increasing crude oil gravity. • The developed correlations showed high accuracy for predicting SARA fractions for four crude oils. • The maximum error was around 9.4% while the minimum was 0.1% for the developed correlations. [ABSTRACT FROM AUTHOR]

Asphaltenes from three crudes were precipitated with a mixture of n-heptane and toluene, the size of the particles formed under different solvent mixtures and different agitation regimes were studied. The kinetic size reduction of aggregates formed with an excess of precipitant agent is followed, contrary to other published studies where the kinetic followed is of growing particles. It was found that the particle size of precipitated asphaltenes decreases as precipitant aromaticity increases and agitation energy rises, which indicates the formation of aggregates bonded by weak forces, since the agitation applied was not of high energy, except for the ultrasonic device. [ABSTRACT FROM AUTHOR]

This paper discusses aquathermolysis process of heavy crude oil from Boca de Jaruco reservoir, which is developed by CSS method. The catalysts based on cobalt, nickel, iron and cupper are used to intensify the in-situ conversion processes. The active form of catalysts generates after steam injection. In second part of work the conversion of aromatic hydrocarbons depending on thermo-catalytic conditions and composition of catalysts are investigated. The thermo-catalytic treatment destructs resin and asphaltene molecules. The destruction products transform into aromatic fractions. The correlation between the C4-phenanthrene/naphtabenzothiophen ratio and the yields of aromatics and resins are revealed. The increase in high-molecular aromatic hydrocarbon, particularly tetramethyl-phenanthrene content is observed. However, the content of heteroatom compounds such as naphtabenzothiophen is constant. Based on IR-spectroscopy, the changes in composition of aromatic fraction are revealed. The lowest value of aromaticity index is detected for experiments with only hydrogen donor (without catalysts) and for experiments with Ni-, Cu-based catalysts. [ABSTRACT FROM AUTHOR]