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Deep eutectic solvents (DESs) are industrially promising solvents and posses numerous applications in wide areas such as metal processing, synthesis media, synthesis of nanoparticles, gas sequestration and many more. In this work, we synthesized and investigated the performance of three deep eutectic solvents (DESs) i.e., reline, glyceline and ethaline in the separation of pure asphaltene from organic solvents, i.e., toluene and n-heptane using experimental techniques and classical molecular dynamics (MD) simulations. The DESs are prepared and characterized by Fourier transform infrared (FTIR) spectroscopy and density meter analysis. The separation and aggregation of asphaltene from the organic solvent phase into the DES phase at various DES concentrations are visually observed using optical microscopy. MD simulations are used to probe the end-to-end distance and diffusion coefficient of the asphaltene molecules in DESs-organic solvent mixtures. Further, the trajectory density contours of asphaltene in three DESs-toluene/n-heptane systems are calculated to analyze asphaltene aggregation in the presence of the DESs. Our experimental-simulations synergistic study shows the superior performance of glyceline DES in toluene and reline DES in n-heptane for efficient separation of the asphaltene., Team Poulumi Dey

One of the possible fluid-fluid interactions during water-flooding in oil reservoirs, that is still debated, is the effect of injected brine salinity on asphaltene destabilization. If asphaltene precipitation is induced by salinity changes in the oil reservoirs and surface facilities, this could have a massive impact on the economy of a low salinity water-flooding project. Therefore, this study aims to investigate the effect of brine salinity on the amount of asphaltene precipitation and the governing destabilization mechanisms. Direct asphaltene precipitation measurements, along with the analyses of optical microscopy images and ion chromatography (IC), indicate that the asphaltene precipitation mechanism is dependent on brine salinity. At a high brine salinity, ions play the primary role as possible nuclei for asphaltene aggregates and might promote asphaltene precipitation through asphaltene-ions bonding. While at low salinity, the polarity of the brine-oil interface causes the asphaltenes to be adsorbed toward the brine-oil interface, and this also might disrupt the stability of asphaltenes in the oil bulk. Of all the brines investigated, the highest amount of asphaltene precipitation was observed for the case in which crude oil was in contact with formation water. Based on the IC results, sulfate and magnesium are the most active ions to play the role of the nucleus in the structure of asphaltene agglomerates. Results also showed that the presence of Naphthenic Acids (NAs) in crude oil composition can affect the amount of asphaltene precipitation.

The article explains that oil sludge has not been sufficiently studied when obtaining fixers for mobile sands and soil, which limits their use in road construction. Taking this into account, we analyzed two samples of oil sludge obtained from Dzharkurgan oil, physical and chemical indicators. Everyone knows that oil sludge is a hydrophobic substance that protects the effect of water on the formed crust of the fixer of mobile sands and soils. In laboratory conditions, the influence of the content of oil sludge on the fixing parameters of the resulting crust in mobile sands and soils was studied. It was revealed that the oil sludge of the Dzharkurgan oil treatment plant and the oil refinery can be used up to 20% in the composition of the obtained fixers of mobile sands and soils, and more than this amount greatly increases the mechanical strength of the formed crust, which negatively affects the phytomelioration of plants.

Globally, the reserves of heavy crude oil are seven times more abundant than that of light crude, and yet, they are underutilized because of their high viscosity and density, which is largely due to the presence of large amounts of asphaltenes. Biotransformation of heavy oil asphaltenes into smaller metabolites can be used for reducing their viscosity. Several microorganisms capable of asphaltene biodegradation have been reported but only few have been characterized for its biotransformation. In the present study, a 9-membered microbial consortium was isolated from an oil contaminated soil. About 72% and 75% asphaltene biotransformation was achieved by growing cells at shake flask level and in a 1.5 l bioreactor, respectively. A representative structure of asphaltene was constructed based on LC–MS, 1H-NMR, 13C-NMR, FT-IR, ICPMS and elemental analysis (CHNS) of n-heptane purified asphaltene from Maya crude oil. Biotransformation of asphaltene, as analyzed by performing 1H-NMR, FT-IR and elemental analysis, resulted in 80% decrease in S and N when compared to the control along with incorporation of oxygen in the structure of asphaltene. About 91% decrease in the viscosity of the Maya crude oil was observed after two weeks when oil: aqueous phase ratio was 1:9. The results suggest that the isolated microbial consortium can be used for biological upgradation of heavy crude oil. To our knowledge, this is the first report where a microbial consortium resulted in such high asphaltene biotransformation.

The adsorption and desorption of asphaltene on silica surface is highly dependent on the heteroatoms present in its structure. Herein, some model asphaltene molecules with different heteroatoms (i.e., N, O, S) at different positions (in the aromatic cores, in the middle and termination of alkane side chains) are selected as the adsorbates to investigate their adsorption and desorption behaviors on silica surface through molecular dynamics (MD) simulation. Results reveal that the characteristic adsorption configuration of asphaltenes is ascribed to the competition between the asphaltene-silica interaction and π–π stacking interaction among the asphaltene polyaromatic rings. The presence of heteroatoms is found to be able to strengthen the interactions between asphaltenes and silica, depending on their type and location. For example, the terminal polar groups, especially the carboxyl (COOH), exhibit the greatest contribution to the electrostatic interaction (increasing from −81 to −727 kJ/mol). The S atoms are also found to increase the van der Waals interaction energies by 25%. According to the equilibrium desorption conformation and density profile, the presence of heteroatoms is found to significantly hinder the desorption of asphaltenes from silica due to the enhanced polar interactions. The impeded desorption is also confirmed by the slower detachment of asphaltenes based on the time-dependent interaction energies and center of mass (COM) distances analysis. Additionally, the terminal polar groups lead to extraordinary desorption properties of asphaltenes. It is observed that the strong asphaltene-silica and asphaltene-water interactions coexist in these systems due to the high polarity and hydrophilicity of the terminal polar groups.

Asphaltenes are surface-active molecules which naturally appear in the crude oil. They can adsorb at the water-oil interface and form a viscoelastic film, which stabilizes emulsion drops and makes water-oil separation extremely challenging. These emulsion drops can cause serious problems in the petroleum industry, so the understanding of the asphaltene film and a reliable method to enhance water-oil separation needs to be established.In this study, we apply the interfacial shear rheology on the water-oil interface to characterize the adsorption of asphaltene. Generally, the evolving asphaltene adsorption results in the increase of interfacial stiffness and brings a transition from viscous-dominated to more viscoelastic response to the interface. However, significant variation in the rheological evolution is observed between the nominally-identical experiments. The direct visualization of the interface reveals the mechanical heterogeneity appearing at the evolving film, from both micron and millimeter scale. This heterogeneity seems to be an inherent feature of the asphaltene film and impact the coalescence of asphaltene-stabilized emulsion drops. In addition, we also reveal that the asphaltenes interfacial rheology can be impacted by the chemical and physical parameters of the experiment. The oil composition such as aromatic fraction, bulk asphaltene composition and the choice of model oil can all influence the evolving rheology. Furthermore, the water-oil geometry, selection of rheometry probes and the way conducted shear rheology can also vary the measured rheological response. Our results thus reveal a more complex adsorption process and interfacial structure than that reported in the literature and provide a deep understanding of how to control the asphaltene adsorption.The asphaltene-stabilized emulsions are often demulsified by the chemical demulsifier. The second focus in this dissertation is investigating how the various chemical demulsifiers impact the asph

The research has been done for removing asphaltene by pickling process of diesel oil from pyrolysis oil self-made by waste rubber in this paper, and the study showed that pickling effect of concentrated sulfuric acid was better than concentrated hydrochloric acid. The best pickling effect was found when the concentration of sulfuric acid was 18.4mol/L, acid to oil ratio, namely, the amount of concentration of sulfuric acid to the amount of diesel oil ratio, was 25%. This experiment proved that removing asphaltene by pickling process using concentrated sulfuric acid was remarkable.

In this work, a study of the adsorption/desorption of n-C7 asphaltenes at low and high concentrations (100 - 30000 mg/L) was performed for which the effects of adsorbent particle size (nano and microsilica), pressure, solvent, and temperature were evaluated. Adsorption/desorption tests on different silica surfaces were performed in batch-mode using UV-vis spectrophotometry and thermogravimetric analyses. Owing to its high surface area and dispersibility, nanosilica adsorbed higher quantities of n-C7 asphaltenes than microsilica. Asphaltene desorption from nanosilica surface was significant, while the desorption from microsilica surfaces was insignificant, suggesting a higher adsorption potential for the latter. Asphaltene adsorption increased with pressure and decreased with temperature. Type of solvent plays a significant role on the asphaltene desorption. The wettability tests for virgin nanosilica and nanosilica contained adsorbed asphaltenes showed that even at high asphaltene loading, the nanoparticles maintained its water-wet nature., Resumo Neste trabalho foi realizado um estudo sobre a adsorção/dessorção de asfaltenos n-C7 em concentrações altas e baixas (100 - 30000 mg/L) no intuito de avaliar os efeitos do tamanho da partícula adsorvente (nano e microsílica), pressão, solvente e temperatura. Testes de adsorção/dessorção em diferentes superfícies de sílica foram realizados em série utilizando análises termogravimétricos e de espectrofotometria UV-vis. Vista sua grande área de superfície e capacidade de dispersão, a nanosílica adsorveu maiores quantidades de asfaltenos n-C7 do que a microsílica. A dessorção de asfalteno da superfície da microsílica foi insignificante, isso sugere a existência de um maior potencial de adsorção para a microsílica. A adsorção de asfalteno aumentou com a pressão e diminui com a temperatura. O tipo de solvente tem um papel preponderante na dessorção de asfalteno. Os testes de molhabilidade para nanosílica virgem e asfaltenos adsorvidos com conteúdo de nanosílica mostraram que mesmo durante uma carga alta de asfaltenos, as nanopartículas preservaram sua natureza de humidade-agua., Resumen En este trabajo, se desarrolló un estudio de la adsorción/desorción de asfaltenos a bajas y altas concentraciones (100 - 30000 mg/L) incluyendo el efecto del tamaño de partícula del adsorbente (nano y microsílice), efecto de la presión, de la temperatura y el tipo de solvente. Las pruebas de adsorción/desorción en las diferentes superficies de sílice se realizaron mediante pruebas por lotes usando espectrofotometría UV-vis y análisis termogravimétricos. Debido a sus especiales características de alta área superficial y dispersabilidad, las nanopartículas de sílice adsorben una mayor cantidad de asfaltenos que la sílice microparticulada. Además, se observó que la desorción de los asfaltenos de las nanopartículas de sílice fue significativa, mientras que para el sistema microparticulado fue insignificante, sugiriendo un mayor potencial de adsorción para la sílice microparticulada. La cantidad de asfaltenos adsorbidos aumentó al incrementar la presión, al mismo tiempo que disminuye al aumentar la temperatura del sistema. También, los resultados obtenidos demuestran que el tipo de solvente juega un papel importante en el proceso de desorción de los asfaltenos. Adicionalmente, se realizaron pruebas de humectabilidad para las nanopartículas de sílice en presencia y en ausencia de asfaltenos adsorbidos y se evidenció que incluso a altas cantidades adsorbidas, las nanopartículas mantienen su condición humectable al agua.

Asphaltene aggregation process was studied using molecular dynamics techniques. Four different structures were used. The first three molecules have a continental structure, with condensed aromatic cores, while the forth has an archipelago structure, with small groups of aromatic rings connected with saturated chains. The molecules were constructed in an atomistic framework, in which atoms are described individually. Interaction forces were calculated at 300 K and 200 atm; Van der Waals and electrostatic interactions were evaluated separately. For all four molecules the solubility parameter was calculated. It was found that Van der Waals interactions due to the presence of aromatic rings and electrostatic forces caused by the presence of heteroatoms such as oxygen, nitrogen and sulfur, are equally relevant in the aggregation of asphaltene molecules. For all molecules it was found asphaltene systems are more stable in aggregation state than in monomeric state. For continental structures, the presence of long ramifications obstructs the formation of asphaltene aggregates. For archipelago structures, the flexibility of the molecules enables the aggregation with other structures. The presence of heteroatoms creates a repulsive force that hinders the aggregation process. The molecular volume and the cohesive energy are also sensitive to the geometric configuration and the composition of the species, which affects the solubility parameter., Se estudió el proceso de agregación de asfaltenos utilizando técnicas de dinámica molecular. Se utilizaron cuatro estructuras diferentes. Las primeras tres moléculas tienen una estructura continental, con núcleos aromáticos condensador, mientras que la cuarta posee una estructura tipo archipiélago, con pequeños grupos de anillos aromáticos conectados con cadenas saturadas. Las moléculas fueron construidas de manera atomística, en la cual cada átomo se describe individualmente. Se calcularon las fuerzas de interacción a 300 K y 200 atm; las fuerzas de Van der Waals y las interacciones electrostáticas fueron evaluadas separadamente. Se calculó el parámetro de solubilidad para las cuatro moléculas. Se encontró que las interacciones de Van der Waals asociadas a los anillos aromáticos y las fuerzas electrostáticas ocasionadas principalmente por la presencia de heteroátomos como oxígeno, azufre y nitrógeno, son igualmente relevantes en la agregación de moléculas de asfalteno. Para todas las moléculas se encontró que los sistemas de asfaltenos tienen menor energía en estado de agregación que en estado monomérico. Para las estructuras continentales, la presencia de largas cadenas obstruye el proceso de formación de agregados. Para las estructuras tipo archipiélago, la flexibilidad de las moléculas facilita la agregación con otras estructuras. La presencia de heteroátomos ocasiona una fuerza repulsiva que dificulta la agregación. El volumen molecular y la energía de cohesión también son sensibles a la configuración geométrica y la composición de las especies, lo cual afecta el parámetro de solubilidad.

97 p. ; ill. ; 30 cm, Vue la forte demande en carburant essence dans le monde, le craquage catalytique a acquis une grande importance dans l'industrie de raffinage du pétrole : c'est un moyen d'augmenter la production d'essence au prix des produits plus lourds et de moindre valeur, qui sans traitements complémentaires ne pourrait être utilisées qu’en tant que combustible. pourrait être utilisées qu’en tant que combustible. L’objectif attendu de cette étude est l’optimisation de la qualité des coupes lourdes pétrolières (fuel, résidu atmosphérique et leurs compoundage à différentes proportionnalités) sur le rendement et la qualité des produits issus du craquage catalytique, et ce en utilisant des différents catalyseurs préparés à base de bentonite en faisant varier le rapport SiO2/ Al2O3. On a aussi déterminé la stabilité agrégative des charges afin de déterminer l’influence des asphaltènes sur les rendements en essence. Finalement, on a analysé les essences obtenues pour connaître l’influence de la nature de la charge sur la qualité d’essence

As a widely accepted concept, bitumen consists of four fractions that can be distinguished by their polarity. Highly polar asphaltene micelles are dispersed in a viscous phase of saturates, aromatics and resins (maltene phase). Different concentrations of asphaltenes in the bitumen result in a range of mechanical response properties. In an interdisciplinary study the impact of the maltene phase and asphaltenes on the linear viscoelastic behavior and the microstructure of bitumen were analyzed by creep recovery testing in a DSR and by atomic force microscopy (AFM). Therefore, bitumen was separated into the maltene and asphaltene fractions and artificial bitumen samples with different, pre-defined asphaltene concentrations were produced and investigated. It was found that the artificially produced, precipitated bitumen samples can be regarded as a representative, bitumen-like material in terms of mechanical behavior and microstructure. Asphaltenes play an important role in the typical viscoelastic behavior of bitumen being mainly responsible for stiffness and elasticity. Also, their concentration appears to be correlated to the occurrence and shape of the bee-like inclusions which can be typically observed by AFM., Structural Engineering, Civil Engineering and Geosciences

For the purpose of experimental verification of the assumption that the elastic properties of heavy petroleum can be characterized by a matrix of elasticity for a transversely isotropic medium, molecular dynamics simulation studies were performed. It is shown that the main structural elements of heavy petroleum are some saturated hydrocarbons, resin-solvated asphaltenes and self-associated asphaltenes. The obtained numerical results of the Young's modulus, shear modulus and Poisson's ratio in a wide temperature range for these compounds suggest that their elastic properties are closer in nature to the properties of solids, rather than amorphous entities. The method presented for determining the elasticity of a complex material in this paper can be found convenient and sufficiently accurate. This is so, since by analyzing the molecular composition of a complex compound and defining the main structural elements of it, properties of each of them can be estimated separately, in a first place, and then a general result can be derived for a substance as a whole.Numerical results obtained in this research may be useful for those who are interested in heavy petroleum fractions rheology, and those who perform numerical studies in petroleum hydrodynamics and acoustics., Исследованы упругие свойства некоторых предельных углеводородов и ассоциатов смолисто-асфальтеновых соединений путем моделирования молекулярной динамики. Получены числовые результаты модуля Юнга, модуля сдвига и коэффициента Пуассона для этих веществ в широком диапазоне температур. Автором предложено оценивать реологические поведение тяжелых нефтепродуктов матрицей упругости трансверсально-изотропного вещества. Показано, что числовые значения матрицы прямо пропорциональны химическому составу нефтепродукта., Досліджені пружні властивості деяких граничних вуглеводнів та асоціатів смолисто-асфальтенових сполук шляхом моделювання молекулярної динаміки. Отримані числові результати модуля Юнга, модуля зсуву та коефіцієнта Пуассона для цих речовин у широкому діапазоні температур. Автором запропоновано оцінювати реологічну поведінку важких нафто-продуктів матрицею пружності трансверсально-ізотропного речовини. Показано, що числові значення матриці прямо пропорційні хімічному складу нафтопродукту.

This paper reviews the impact of asphaltenes on wax crystallization and on the properties of crude oils, and the consequences thereof on the flow assurance of waxy crude oil. It initially includes studies of the crystallization of both pure n-alkanes as well as the mixtures thereof, because they have led to an understanding of how their precipitation occurs along with their transitions of crystalline phases, particularly, by studies of X-ray diffraction (XRD). This is followed by the studies and results of crystallization in crude oils and/or the fractions thereof and how their properties are affected in the presence of asphaltenes. The results on the influence of asphaltenes are inconclusive and sometimes contradictory: some confirm that their presence decreases pour point, others affirm that it increases it and yet others say there is no effect. Similar results have been reported for properties such as crystallization point, phase transition and rheological properties. The influence of the chemical structure of asphaltenes on the change in crude oil properties has not been generalized either. It has been inferred that is possibly due to the interaction between aliphatic chains of asphaltenes and waxes, and it has been established that there is synergy in coprecipitation due to evidence in the analysis of organic deposits., É apresentada uma revisão do efeito que os asfaltenos têm na cristalização de parafinas, nas propriedades de crus parafínicos e nas consequências na garantia de escoamento. Inicialmente são incluídos os estudos de cristalização de n-alcanos puros e de suas misturas onde foi possível entender como ocorre sua precipitação e transições de fases cristalinas, especialmente, por estudos de difração de raios-X (DRX). São analisados os resultados de estudos de cristalização em crus e/ou suas frações e como a presença dos asfaltenos afeta suas propriedades. Sobre a influência dos asfaltenos, os resultados não são conclusivos e em ocasiões são contraditórios: alguns confirmam sua contribuição para diminuir o ponto de fluidez, outros que o aumenta e em alguns casos que não o afeta. Resultados semelhantes são relatados para o ponto de cristalização, a transição de fases e as propriedades reológicas. Também não é possível generalizar qual é a influência da estrutura química dos asfaltenos sobre as propriedades dos crus. Infere-se que possivelmente é devida à interação entre suas cadeias alifáticas com as parafinas e estabelece-se que existe sinergia na coprecipitação pela evidência nas análises dos depósitos orgânicos., Se presenta una revisión del efecto que tienen los asfaltenos en la cristalización de parafinas, en las propiedades de crudos parafínicos y las consecuencias en el aseguramiento de flujo. Inicialmente se incluyen los estudios de cristalización de n-alcanos puros y de sus mezclas donde se ha podido entender como ocurre su precipitación y transiciones de fases cristalinas, especialmente, por estudios de difracción de rayos-X (DRX). Se analizan los resultados de estudios de cristalización en crudos y/o sus fracciones y cómo la presencia de los asfaltenos afecta sus propiedades. Sobre la influencia de los asfaltenos, los resultados no son concluyentes y en ocasiones contradictorios: algunos confirman su contribución a disminuir el punto de fluidez, otros que lo aumenta y en algunos casos que no hay efecto. Resultados semejantes se han reportado para el punto de cristalización, la transición de fases y propiedades reológicas. Tampoco se ha podido generalizar cuál es la influencia de la estructura química de los asfaltenos sobre las propiedades de los crudos. Se infiere que posiblemente se deba a la interacción entre sus cadenas alifáticas con las parafinas y se ha establecido que existe sinergia en la coprecipitación por la evidencia en los análisis de los depósitos orgánicos.

The main objective was to obtain kinetic and thermodynamic equilibrium of asphaltene sorption onto powder ROCK obtained from the Guadalupe formation (washed and unwashed) at different times, temperatures and concentrations. However, the effect of temperature in the equilibrium sorption is not significant. Rock powders were characterized by N2 sorption at -196°C. Equilibrium sorption of asphaltenes in rock powders, within a range of concentrations from 250 to 1500 ppm, was determined using a static method. Sorption curves show Type I behavior, according to IUPAC. Langmuir model was used for computing the monolayer asphaltene content values for the sorption at different temperatures, showing a good fit respect to the experimental data. Sorption kinetics of asphaltenes in rock samples is function of the concentration and for concentrations of 1500 ppm equilibrium is reached about 90 min. Pseudo first order and pseudo second order kinetic models were applied to the experimental data for the different concentrations for the two rock samples with a better result for the pseudo-first order kinetic model. The washing effect on the equilibrium was not significant; however the adsorptive capacity of the rock without washing was slightly higher than the rock washed with n-heptane and toluene.

The main objective was to obtain kinetic and thermodynamic equilibrium of asphaltene sorption onto powdered rock obtained from the Guadalupe formation (washed and unwashed) at different times, temperatures and concentrations. However, the effect of temperature in the equilibrium sorption was not significant. Rock powders were characterized by N2 sorption at -196°C. Equilibrium sorption of asphaltenes in rock powders, within a range of concentrations from 250 to 1500 ppm, was determined using a static method. Sorption curves show Type I behavior, according to IUPAC. The Langmuir model was used for computing the monolayer asphaltene content values for the sorption at different temperatures, showing a good fit with respect to the experimental data. Sorption kinetics of asphaltenes in rock samples is a function of the concentration and for concentrations of 1500 ppm equilibrium is reached at about 90 min. Pseudo first order and pseudo second order kinetic models were applied to the experimental data for the different concentrations for the two rock samples, with a better result for the pseudo-first order kinetic model. The washing effect on the equilibrium was not significant; however the adsorptive capacity of the rock without washing was slightly higher than the rock washed with n-heptane and toluene, El principal objetivo del estudio fue obtener la cinética y el equilibrio termodinámico de la sorcion de asfaltenos en polvo de roca obtenida de la formación Guadalupe (lavada y sin lavar), a diferentes tiempos, temperaturas y concentraciones. Sin embargo, el efecto de temperatura en el equilibrio de sorción no era significativo. Los polvos de roca fueron caracterizados por sorción de N2 a -196°C. El equilibrio de sorcion de los asfaltenos en los polvos de roca, dentro de un rango de concentraciones desde 250 hasta 1500 ppm, fue determinado usando un método estático. Las curvas de sorcion muestran un comportamiento Tipo I, según la IUPAC. El modelo de Langmuir se usó para calcular los valores del contenido de asfaltenos monocapa para la sorcion a diferentes temperaturas, mostrando un buen ajuste con respecto a los datos experimentales. La cinética de sorcion de los asfaltenos en muestras de rocas es función de la concentración y para concentraciones de 1500 ppm el equilibrio es alcanzado alrededor de 90 min. Se aplicaron los modelos cinéticos de pseudo primer orden y pseudo segundo orden a los datos experimentales para las diferentes concentraciones para las dos muestras de rocas con un mejor resultado para el modelo cinético de pseudo-primer orden. El efecto de lavado en el equilibrio no fue significativo, sin embargo la capacidad adsortiva de la roca sin lavar fue ligeramente mayor que la roca lavada con n-heptano y tolueno

En el presente trabajo se realiza un modelamiento termodinámico de la precipitación de asfaltenos para predecir el comportamiento de estos en un fluido de un campo colombiano, aplicando un modelo multi-sólido, y una seudo-caracterización el cual trata el asfalteno en proceso de precipitación como un solo seudo-componente en estado sólido, que reside en un fluido cuyas fases se modelan utilizando una EOS cúbica (ecuación de estado). Como producto final este trabajo pretende brindar una herramienta que permita predecir el comportamiento de la precipitación de asfaltenos y, de esta forma, como complemento en la toma de decisiones, evitar futuros problemas de producción y así minimizar los altos costos operacionales. Grupo de investigación: simulación de yacimientos y recobro mejorado

The creation of new polymer compounds to be added to asphalt has drawn considerable attention because these substances have succeeded in modifying the asphalt rheologic characteristics and physical properties for the enhancement of its behavior during the time of use. This work explains the synthesis of a new graft copolymer based on an asphalt fraction called asphaltene, modified with maleic anhydride. Polystyrene functionalization is conducted in a parallel fashion in order to obtain polybenzylamine resin with an amine - NH2 free group, that reacts with the anhydride graft groups in the asphaltene, thus obtaining the new Polystyrene/Asphaltene graft copolymer., La creación de nuevos compuestos poliméricos para ser adicionados al asfalto, ha llamado la atención de manera considerable debido a que estas sustancias han logrado modificar las características reológicas y propiedades físicas del asfalto, con la finalidad de mejorar su comportamiento en el tiempo de uso. El presente trabajo explica, la síntesis de un nuevo copolímero de injerto a partir de una fracción del asfalto llamada asfalteno, la cual es modificada con anhídrido maleico. Paralelamente se realiza la funcionalización del poliestireno, resina polibencilamina, esta posee un grupo amina - NH2 libre que reacciona con los grupos anhídro, injertados en el asfalteno, y así obtener el nuevo copolímero de injerto Poliestireno/Asfalteno.

The adsorption of extracted and purified samples of asphaltenes and resins onto gold surfaces has been studied as a function of bulk concentration using a quarts crystal microbalance with dissipation measurements (QCM-D). With this device, which works equally well in transparent, opaque, and nontransparent samples, the adsorbed amount is measured through a change in resonant frequency of the quartz oscillator. The measured change in dissipation reports on changes in layer viscoelasticity and slip of the solvent at the surface. The results show that the adsorbed amount for resins from heptane corresponds to a rigidly attached monolayer. The adsorbed amount decreases with increasing amount of toluene in the solvent and is virtually zero in pure toluene. Asphaltenes, on the other hand, adsorb in large quantities and the mass and dissipation data demonstrate the presence of aggregates on the surface. The aggregates are firmly attached and cannot be removed by addition of resins. On the other hand, resins and asphaltenes associate in bulk liquid and the adsorption from mixtures containing both resins and asphaltenes is markedly different from that obtained from the pure components. Hence, we conclude that preformed resin aggregates adsorb to the surface. These results are compared and discussed in relation to adsorption from crude oil diluted in heptane/toluene mixtures., QC 20100525 NR 20140804

High-resolution mass spectrometry indicates that the isotopic abundance of V-50 Of the Late Cretaceous La Luna petroleum asphaltenes of marine origin (highly enriched with V GT 2000 ppm)fi higher by about 3.5% than that of the inorganic source (VOSO4 X 5H(2)O, Merck). We propose that the difference in the V-50/V-51 values between the La Luna petroleum asphaltenes and the inorganic source can be best ascribed to the biological processing of seawater vanadium. The fact that the V isotopic compositions of petroleum asphaltenes vary over avery narrow range (2.46-2.52) suggests essentially the same (or similar) and fixed biological source of vanadium. (C) 2000 Elsevier Science Inc. All rights reserved.

The thermal behavior of vanadyl porphyrins was studied by electron spin resonance during heating of kerogens, isolated from the La Luna (Venezuela) anti Serpiano (Switzerland) bituminous rocks, at 250 degrees C for 1 to 20 days in the presence of air. During the thermal treatment of the kerogens, the vanadyl porphyrins resonance signals decrease monotonically and become quite small after 6 days of heating. Concomitantly, new vanadyl signals appear and, at longer heating limes, dominate the spectrum. It is suggested that the secondary vanadyl species must have been formed from vanadyl porphyrins. Similar conversions of vanadyl porphyrins are observed under the same experimental conditions for asphaltenes extracted from the La Luna and Serpiano rocks, and floating asphalt from the Dead Sea (Israel). A comparison of the spin-Hamiltonian parameters for vanadyl porphyrins and the vanadyl compounds obtained during pyrolysis of the kerogens/asphaltenes suggests that the latter are of a non-porphyrin type. For comparison a study was conducted on Western Kentucky No. 9 coal enriched with vanadium ( GT 400 ppm) from six mines. AII the coal sam!,les:show only the presence of predominant by non-porphyrin vanadyl compounds, similar to those generated through laboratory heating of the kerogens/asphaltenes in ail: In addition, some samples also contain a minor amount of vanadyl porphyrins.

© 2019, © 2019 Taylor & Francis Group, LLC. This paper discusses the physical simulation of aquathermolysis for heavy oil in the presence of minerals–dolomite and calcite. According to the SARA-analysis and IR-spectroscopy, the presence of calcite provides significant effects on the reduction of resins and asphaltenes, their condensability and aromaticity by destructing the least stable C-S-C bonds. Based on the results of gas chromatography, the thermal conversion of heavy oil increased the hydrocarbon content with homologous series of С19-С30. The analysis of geochemical coefficients revealed the high maturity of organic matters in thermally conversed heavy oil from model system with dolomite.

© Kazan Federal University (KFU)*. The resin-asphaltene model samples are studied by nuclear magnetic resonance (NMR). According to the differences in spin-spin relaxation times, we are able to distinguish two components of the resin in the mixture. The first component with slower relaxation rate corresponds to the resin in bulk. The second component with the much higher relaxation rate conforms to the resin interacting with the asphaltene particles. The dependence of the ratio between the contributions of these functions on the particle size of asphaltenes is found. It is shown that the fraction of resin molecules interacting with asphaltenes is described by the power dependence on the particle size in terms of one particle. In this case, the proportionality to the volume is given by the value of the exponent (0.9) that is closer to unity, while this exponent is 1.33 for the particle surface. This result is not consistent with the conventional simple model of an asphalt particle surrounded by a solvate resin layer. A hypothesis is formulated about the partial dissolution of asphaltene molecules in the resin is formulated, which is also confirmed by the dependence in the NMR signal of the fraction of the solid component on the particle size of asphaltenes. It is shown that the kinetic dependences of the fraction of the solid component, as well as the fraction of the resin molecules in the state of interaction with asphaltenes, reflect in general the opposite processes, although they are characterized by a close time value of 20 days.

© Kazan Federal University (KFU). Porous silica materials offer wide range of possibilities for enhancement of the productivity of oil reservoirs. However the mechanism of adsorption of polar components of crude oil on silica surface is poorly understood that hinders technological improvement of supports and oil extraction. We have synthesized opal films with the silica microspheres size of about 360 ± 20 nm, specific surface area of 5.2 m 2 × g -1 and pore size of 230 nm. We have fractionated and characterized oil and oil asphaltenes from heavy (Ashalchinskoe) oil. By pulsed electron paramagnetic resonance (EPR) and double electron-nuclear resonance (ENDOR) in the W-band frequency range (microwave frequency of 94 GHz, magnetic field of 3.4 T) we have studied the adsorption of oil asphaltenes on the surface of opal samples using the intrinsic for asphaltenes paramagnetic vanadylporphyrins (VO) complexes. 1H ENDOR spectra are found to be different for initial and the adsorbed samples in their central parts (that is a sign of asphaltenes VO disaggregation) whereas no significant changes in the W-band EPR spectra were detected. Contrasting to alumina support, no strong electron-proton interaction with the protons on the surface of SiO 2 (presumably, silanol groups) was found and infiltration of the oiled opal films with gasoline changes the central part of 1H ENDOR spectra. It shows that the proton containing groups on the surface of amorphous SiO 2 sample can significantly change the asphaltene adsorption properties and ENDOR of the intrinsic for oil paramagnetic centers could be used for the characterization of surface state in porous media in situ or operando.

© Kazan Federal University (KFU). The resin-asphaltene model systems with different sizes of asphaltenes are studied by nuclear magnetic resonance (NMR) using the solid-echo sequence. For systems with particle sizes of asphaltenes greater than 50 µm, the form of relaxation attenuation consists of two components, one of which is characterized by a typical asphaltene relaxation time of about 20 µs. In this case, the Gaussian form describes the relaxation attenuation of this component, which is typical for the NMR signal in disordered solids. At the same time, it is found that the share of the solid component in the NMR signal decreases with decreasing particle size of asphaltenes. The signal drops to zero when the size of asphaltenes particles reaches 10 microns. Based on the estimates of the rotational motion correlation time for an asphaltene particle in a dispersion medium (resin) with a known viscosity value, the influence of two factors is discussed: the difference in the values of macro-and microviscosity of the resin, as well as the possibility of partial dissolution of asphaltenes particles in the resin. The results of repeated measurements for a long time indicate the existence of a reverse process in the system, leading to the aggregation of asphaltene particles.

© SGEM2018. Heavy crudes and natural bitumen might present one of the accessible energy resources for the period of time necessary for the adoption of novel energy technologies of the future. Their development is characterized with low profitability, due to peculiarities of composition, mainly high content of high-molecular paraffin, resin and asphaltenes. At the present time in exploration of heavy hydrocarbon resources, thermal methods of production are being given more attention to. One of the key problems of thermal methods related to production of heavy crudes with high concentration of paraffin wax is precipitation of asphalt-resin-paraffin deposits in the formation and in oilfield equipment. In the present work the peculiarities of redistribution of saturated hydrocarbons between the initial crude and asphalt-resin-paraffin deposits produced under thermal steam treatment were investigated. Qualitative composition of components of deposits, melting point and dissolving capacity of hydrocarbon phase were characterized by thermal analysis. On the curves of heat flow moments of appearance and disappearance of crystalline phase of paraffin wax were detected. The amount of crystalline phase in the examined deposits was estimated by crystallization enthalpy data. Slight difference in melting and crystallization enthalpy during heating and cooling was observed, which indicated the formation of crystalline phase. The presence of low-molecular n-alkanes in asphaltenes of asphalt-resin-paraffin deposits point out to their participation in the formation of nucleation sites.

© 2018, © 2018 Taylor & Francis Group, LLC. 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. The third part of paper discusses conversion of resins and asphaltenes. The influence of thermo-catalytic conditions and composition of catalysts are also studied. The destruction of resins and asphaltenes are observed after thermocatalytic treatments. The changes in composition of resins and asphaltenes are revealed by IR-spectroscopy data.

© 2018, Pleiades Publishing, Ltd. An approach to investigate self-assembly of oil disperse systems based on high-field electron nuclear double resonance has been suggested. As exemplified by asphaltenes, the oil components most prone to self-assembly, the formation of planar rather than multilayer structures has been directly evidenced experimentally. The suggested method can be applied to elucidate the self-assembly mechanism in wide range of organic objects.

© Kazan Federal University (KFU).Changes of paramagnetic centers (PC) concentration in dispersed petroleum systems were studied in the process of low-temperature thermolysis. The kinetic model of PC concentration dynamics based on the processes of unpaired electrons formation during singlet-triplet transitions, weak chemical bonds dissociation and recombination of free radicals is proposed. PACS: 75.20.-g, 96.20.Dt, 02.30.Hq

© Kazan Federal University (KFU).Changes of paramagnetic centers (PC) concentration in dispersed petroleum systems were studied in the process of low-temperature thermolysis. The kinetic model of PC concentration dynamics based on the processes of unpaired electrons formation during singlet-triplet transitions, weak chemical bonds dissociation and recombination of free radicals is proposed. PACS: 75.20.-g, 96.20.Dt, 02.30.Hq

TT-Fed/TT-Reg-5, The objective of this research is to evaluate the characterization of asphalt binder through TLC/FID testing and SARA grouping. The results will be further analyzed and compared with the available GPC results and other available characterizations of the asphalt binders. Furthermore, the results will be correlated with performance.