Kazan Federal University

Injection of destructive hydrogenation catalysts into heavy oil reservoirs is a technol. that has already been implemented in the fields.Effect of catalysts in oil refining and viscosity reductionThe main reason for such reduction is intensive catalytic breakdown of carbon-heteroatom bonds in asphaltene mols.In most of the realized projects, the catalysts are formed in situ by decomposition of a pre-introduced precursor containing catalytically active metals.There has been evidence that the presence of certain surfactants significantly enhances the efficiency of such catalysts.These surfactants were thought to peptization asphaltene agglomerates, involve more asphaltenes in the degradation processes and hence increase the asphaltene conversion rate.In this work, synthesis of a nanoscale catalyst derived from NaNiO₂ under hydrothermal conditions was investigated, employing the use of two thermally stable non-ionic surfactants.The combination of aquathermolysis catalysts with surfactants provides oil refining mainly due to thermal degradation of heavy fractions such as resins and asphaltenes.Concurrently, there is a significant reduction of asphaltene fraction content up to 40 %, as well as an increase in the content of saturated and aromatic hydrocarbons in heavy oil by 20 and 30 % accordingly.The content of gaseous C₂-C₄ alkenes increased by 45 %.Complete neutralization of H₂S was observed when surfactants and Na-containing precursors were injected together.Asphaltene degradation was the main contributor to the 70 % reduction in oil viscosity.This technol. of combined catalyst and surfactant injection for heavy oil refining is effective and environmentally safe due to H₂S neutralization.

The exptl. data on the phase transition enthalpies and heat capacities of numerous polyphenols, polyanilines and aminophenols in the condensed and ideal gas state were analyzed to obtain the reliable values at 298.15 K.For this purpose, we combined exptl. data on the crystal, liquid, and ideal gas heat capacities and fusion, sublimation and vaporization enthalpies.Significant part of these data, including the ideal gas heat capacities of 16 mols., vapor pressures and vaporization enthalpies of 1,3-diaminobenzene and 1,6-dihydroxynaphthalene, were obtained in this work.A modified approach for the estimation of the temperature dependence of vaporization enthalpies of polyphenols, polyanilines and aminophenols showing performance competitive with the exptl. one was proposed based on the anal. performed.

The viscosity of crude oil is an important phys. property that largely determines the fluidity of oil and its ability to seep through porous media such as geol. rock.Predicting crude oil viscosity requires the development of reliable models that can reproduce viscosity over a wide range of temperatures and pressures.Such viscosity models must operate with a set of phys. characteristics that are sufficient to describe the viscosity of an extremely complex multi-phase and multi-component system such as crude oil.The present work considers empirical data on the temperature dependence of the viscosity of crude oil samples from various fields in Russia, China, Saudi Arabia, Nigeria, Kuwait and the North Sea.For the first time, within the reduced temperature concept and using the universal scaling viscosity model, the viscosity of crude oil can be accurately determined over a wide temperature range: from low temperatures corresponding to the amorphous state to relatively high temperatures, at which all oil fractions appear as melts.A novel methodol. for determining the glass transition temperature and the activation energy of viscous flow of crude oil is proposed.A relationship between the parameters of the universal scaling model for viscosity, the API gravity, the fragility index, the glass transition temperature and the activation energy of viscous has been established for the first time.It is shown that the accuracy of the results of the universal scaling model significantly exceeds the accuracy of known empirical equations, including those developed directly to describe the viscosity of petroleum products.