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Copyright of Revista CienciaUAT is the property of Universidad Autonoma de Tamaulipas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista CIENCIA UNEMI is the property of Universidad Estatal de Milagro (UNEMI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract This study was focused on the development of a surface alteration protocol for aluminum discs based on the asphaltenes precipitation, to the future development of cellular aluminum treated superficially for the treatment of contaminated water with oil. Roughness tests were developed to guarantee homogeneity of the samples considered. Water and oil contact angles were measured before and after treatment to evaluate variations in the surface affinity of the specimens and it was found that, although there are variations consistent with the increase of the surface hydrophobicity, this is not significant inside the design of experiments proposed within the methodology. [ABSTRACT FROM AUTHOR]

This research presents the results of the application of coconut oil (Cocos nucifera), as a stabilizer of asphaltenes and the effect of warming on their performance, in a sample of Monagas state oil, Venezuela. The coconut oil was subjected to 11 temperatures between 25 and 200 ° C, and then 12 mixtures with diesel oil were prepared. The flocculation onset of the asphaltenes was determined to samples of 10 mL of petroleum dosed with 8µL of each mixture, applying successive volumes of n-heptane until observing the aggregates in an optical microscope and the dispersion point applying successive volumes of Xylene up to observe the dissolution of the aggregates. The Instability Index was determined as the ratio between the dispersion point and the flocculation onset. ANOVA analysis was applied to establish the significance of the effect of temperature on the Stability Index. It was concluded that mixtures of coconut oil and diesel increase the stability of asphaltenes when applied to the oil sample, however the temperature has a statistically significant effect. The effect of the oil was positive until the sample heated to 130 °C, losing its effect from that temperature. [ABSTRACT FROM AUTHOR]

Heavy metals are present in porphyrins in oil asphaltenes. High content of V and Ni could be attractive to produce high value metal oxides. These metals are undesirable due to corrosion issues and catalyst contamination in cracking processes. The purpose of this project was to prepare an electrochemical cell, with graphite work electrode, wire Ag counterelectrode and a Ag/AgNO reference electrode, in order to evaluate and make the electrochemical characterization and deposition of V and Ni content in resin asphaltene concentrate and pure asphaltenes obtained from Colombian heavy oils. High resolution analytics before and after the deposition was done: elemental analysis, FT-IR, and atomic absorption. The variables as work potential, reaction time and electrode materials during the electro-reduction was evaluated by cyclic voltammetry and chronoamperommeter in two solutions: (I) Tetrahydrofuran and LiClO4 at 0.02 M, and (II) 20% CH3OH, 0.5 % H3PO4, 0.1 M LiClO4 in acetonitrile. Results are discussed compared with traditional method of demetallization by acid digestion. [ABSTRACT FROM AUTHOR]

It was studied the morphology of asphaltenes Zuata, Boscan and Morichal from differents heavy and extra heavy Venezuelan oils, and San Jacinto asphaltenes from an extra heavy Peruvian oil through scanning electron microscopy. The spectroscopy characterization was performed by infrared absorption, proton nuclear magnetic resonance and carbon 13 nuclear magnetic resonance to the resins and asphaltenes Boscan. In order to study the effect of the precipitating agent, the asphaltenes Zuata and Morichal were precipitated using n-pentane and n-heptane as aliphatic solvents, it found that according decreases the molecular mass of precipitating agent increases the porosity of the asphaltenes after completing the respective Soxhlet extraction to remove resins adsorbed and occluded. Asphaltenes Boscan and San Jacinto were precipitated with n-heptane, showed similar morphological structures, where the only difference may be attributable to the composition of oil as well as the origin and geochemical processes involved in the formation of oil. Moreover spectroscopic characterization performed for asphaltene and resin Boscan precipitated with n-heptane showed the high content of aromatic rings, linear and branched aliphatic chains present in its structure. [ABSTRACT FROM AUTHOR]

Asphaltenes are polar polynuclear compounds of high molecular weight, which form a colloidal suspension in crude oil. These compounds tend to precipitate on the internal surface of pipelines and equipment, which may cause extraction and crude fractionation technological processes problems. For this reason, we have developed chemicals that stabilize the colloidal aggregates, allowing the oil to flow and modify their rheological properties. We used dynamical systems tools to study the effect of an asphaltene stabilizer called BRV, in oil. It is further proposed a model for assessing the ratio of precipitation of asphaltenes, which can quantify the effectiveness of a viscosity reducer, finding that the increase in the concentration of the dispersant can reduce the coefficient of precipitation. [ABSTRACT FROM AUTHOR]

Crude oil and seawater form a dispersed system in which petroleum droplets tend to coalesce reducing the interface area, hampering the biological treatment efficiency methods used in the sea decontamination when oil spills occur. Therefore chemicals have been developed, such as those derived from a viscosity bioreducer (VBR), which increase the degree of dispersion of this system. To evaluate effectiveness of these dispersants it was used a method based on the pattern fractal dimension formed by the interface seen in 2D. Since images of dispersed system it was also determined the particle size distribution and the total area of the interface. The analysis of these experimental results showed that there was a significant positive correlation between the fractal dimension and the interface estimated area, as well as a correspondence between the increase in the fractal dimension and turbidity with increasing dispersion. This technique was used to evaluate the effectiveness of the action of VBR and VBR-C in three types of crude. It was demonstrated in all cases that dispersion degree increasing and the agents effectiveness depends on the composition of crude and decreases with increase in the concentration of asphaltenes. [ABSTRACT FROM AUTHOR]

Copyright of Revista ION is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Fuentes, El Reventón Energético is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Fuentes, El Reventón Energético is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Fuentes, El Reventón Energético is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Se presenta un estudio de laboratorio de mezclas de Diesel-Fuel oil, enfocado en evaluar la viscosidad, la concentración de asfaltenos y la estabilidad de las mezclas. El estudio, basado en la teoría termodinßmica de Flory-Huggins, indica una relación significativa entre la viscosidad y la presencia de asfaltenos y demuestra la incidencia de los asfaltenos en la inestabilidad de las mezclas consideradas.