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Sample records for oil components asphaltene

  1. Characterisation of crude oil components, asphaltene aggregation and emulsion stability by means of near infrared spectroscopy and multivariate analysis

    Energy Technology Data Exchange (ETDEWEB)

    Aske, Narve

    2002-06-01

    Effective separation of water-in-crude oil emulsions is a central challenge for the oil industry on the Norwegian Continental Shelf, especially with the future increase in subsea and even down-hole processing of well fluids. The mechanisms and properties governing emulsion stability are far from fully understood but the indigenous surface active crude oil components are believed to play a major role. In this work a thorough physico-chemical characterisation of a set of crude oils originating from a variety of production fields has been performed. Crude oil properties responsible for emulsion stability were identified by use of multivariate analysis techniques like partial least squares regression (PLS) and principal component analysis (PCA). Interfacial elasticity along with both asphaltene content and asphaltene aggregation state were found to be main contributors to emulsion stability. Information on a crude oils ability to form elastic crude oil-water interfaces was found to be especially crucial when discussing emulsion stability. However, measured values of interfacial elasticity were highly dependent on asphaltene aggregation state. Several experimental techniques was utilised and partly developed for the crude oil characterisation. A high-pressure liquid chromatography (HPLC) scheme was developed for SARA-fractionation of crude oils and an oscillating pendant drop tensiometer was used for characterisation of interfacial rheological properties. For emulsion stability a cell for determining the stability as a function of applied electric fields was used. In addition, near infrared spectroscopy (NIR) was used throughout the work both for chemical and physical characterisation of crude oils and model systems. High pressure NIR was used to study the aggregation of asphaltenes by pressure depletion. A new technique for detection of asphaltene aggregation onset pressures based on NIR combined with PCA was developed. It was also found that asphaltene aggregation is

  2. A molecular-thermodynamic framework for asphaltene-oil equilibria

    Energy Technology Data Exchange (ETDEWEB)

    Wu, J.; Prausnitz, J.M. [Univ. of California, Berkeley, CA (United States). Dept. of Chemical Engineering]|[Lawrence Berkeley National Lab., CA (United States). Chemical Sciences Div.; Firoozabadi, A. [Reservoir Engineering Research Inst., Palo Alto, CA (United States)

    1997-02-01

    Asphaltene precipitation is a perennial problem in production and refinery of crude oils. To avoid precipitation, it is useful to predict the solubility of asphaltenes in petroleum liquids as a function of temperature, pressure and liquid-phase composition. In the molecular-thermodynamic model presented here, both asphaltenes and resins are represented by pseudo-pure components, and all other components in the solution are represented by a continuous medium which affects interactions among asphaltene and resin particles. The effect of the medium on asphaltene-asphaltene, resin-asphaltene, resin-resin pair interactions is taken into account through its density and molecular-dispersion properties. To obtain expressions for the chemical potential of asphaltene and for the osmotic pressure of an asphaltene-containing solution, the authors use the integral theory of fluids coupled with the SAFT model to allow for asphaltene aggregation and for adsorption of resin on asphaltene particles. With these expressions, a variety of experimental observations can be explained including the effects of temperature, pressure and composition on the phase behavior of asphaltene-containing fluids. For engineering application, the molecular parameters in this model must be correlated to some macroproperties of oil such as density and molecular weight. When such correlations are established, it will be possible to calculate asphaltene-precipitation equilibria at a variety of conditions for realistic systems.

  3. Kinetics of asphaltene precipitation from crude oils

    Energy Technology Data Exchange (ETDEWEB)

    Maqbool, T.; Hussein, I.A.; Fogler, H.S. [Michigan Univ., Ann Arbor (United States). Dept. of Chemical Engineering

    2008-07-01

    The kinetics of asphaltene precipitation from crude oils was investigated using n-alkane precipitants. Recent studies have shown that there is a kinetic phenomenon associated with asphaltene precipitation. This study showed that the time needed to precipitate the asphaltenes can vary from a few minutes to several months, depending on the amount of n-alkane precipitant added. As such, the onset of asphaltene precipitation is a function of the concentration of precipitant and time. A technique to quantify the amount of asphaltenes precipitated as a function of time and precipitant concentration was presented. This study also investigated the kinetic effects caused by various precipitants. Optical microscopy was used to monitor the growth of asphaltene aggregates with time. Refractive index measurements provided further insight into the kinetics of asphaltene precipitation. Polarity based fractionation and dielectric constant measurements were used to compare the nature of asphaltenes precipitated early in the precipitation process with the asphaltenes precipitated at later times. It was concluded that asphaltenes precipitating at different times from the same crude oil-precipitant mixture are different from one another. 3 refs.

  4. Asphaltene Precipitation inHeavy-Oil Systems

    OpenAIRE

    Verås, Tor Jørgen

    2011-01-01

    Vapor-Assisted Petroleum Extraction (VAPEX) is a relatively new and promising method for recovering heavy crude oils in Canada. The technique upgrades the oil in-situ through asphaltene precipitation, but it may also cause damage to the formation by clogging its pore throats. This thesis brings some clarity to what asphaltenes are and how they form from mixes of bitumen and solvent, depending on the type and amount of solvent used. This was investigated through a series of laboratory experime...

  5. Waxes and asphaltenes in crude oils

    Energy Technology Data Exchange (ETDEWEB)

    Thanh, N.X. [Branch of Vietnam Petroleum Institute, Ho Chi Min City (Viet Nam). Dept. of Geochemistry; Hsieh, M.; Philp, R.P. [University of Oklahoma, Norman, OK (United States). School of Geology and Geophysics

    1999-07-01

    High molecular weight (HMW) hydrocarbons (> C{sub 40}) and asphaltenes are important constituents of petroleum, and can cause problems related to crystallization and deposition of paraffin waxes during production and transportation, as well as in the formation of tar mats. However, traditional methods to isolate asphaltene fractions, by adding 40 volumes in excess of low boiling point solvents such as pentane, hexane or heptane, can produce asphaltene fractions which are contaminated with a significant amount of microcrystalline waxes (> C{sub 40}). The presence of these microcrystalline waxes in the asphaltene fractions has the potential to provide misleading and ambiguous results in modeling and treatment programs. The sub-surface phase behaviour of an asphaltene fraction will be quite different from that of a wax-contaminated asphaltene fraction. Similarly accurate modelling of wax drop-out requires information on pure wax fractions and not asphaltene-dominated fractions. Hence the aim of this paper is to describe a novel method for the preparation of wax-free asphaltene fractions. In addition, this method provides a quantitative subdivision of the wax fraction into pentane soluble and insoluble waxes which, when correlated with physical properties of crude oil such as viscosity, pour point, cloud point, etc., may help explain causes of wax deposition during production, transportation and storage of petroleum. (author)

  6. Asphaltene precipitates in oil production wells

    DEFF Research Database (Denmark)

    Kleinitz, W,; Andersen, Simon Ivar

    1998-01-01

    At the beginning of production in a southern German oil field, flow blockage was observed during file initial stage of production from the oil wells. The hindrance was caused by the precipitation of asphaltenes in the proximity of the borehole and in the tubings. The precipitates were of solid...

  7. Influence of asphaltene aggregation and pressure on crude oil emulsion stability

    Energy Technology Data Exchange (ETDEWEB)

    Auflem, Inge Harald

    2002-07-01

    Water-in-crude oil emulsions stabilised by various surface-active components are one of the major problems in relation to petroleum production. This thesis presents results from high-pressure separation experiments on ''live'' crude oil and model oil emulsions, as well as studies of Interactions between various indigenous stabilising materials in crude oil. A high-pressure separation rig was used to study the influence of gas and gas bubbles on the separation of water-in-crude oil emulsions. The results were interpreted as a flotation effect from rising gas bubbles, which led to increased separation efficiency. The separation properties of a ''live'' crude oil were compared to crude oil samples recombined with various gases. The results showed that water-in-oil emulsions produced from the ''live'' crude oil samples, generally separated faster and more complete, than emulsions based on recombined samples of the same crude oil. Adsorption of asphaltenes and resins onto a hydrophilic surface from solutions with varying aromatic/aliphatic character was investigated by a quarts crystal microbalance. The results showed that asphaltenes adsorbed to a larger degree than the resins. The resins were unable to desorb pre-adsorbed asphaltenes from the surface, and neither did they adsorb onto the asphaltene-coated surface. In solutions of both of resins and asphaltenes the two constituents associated in bulk liquid and adsorbed to the surface in the form of mixed aggregates. Near infrared spectroscopy and pulsed field gradient spin echo nuclear magnetic resonance were used to study asphaltene aggregation and the influence of various amphiphiles on the asphaltene aggregate size. The results showed Interactions between the asphaltenes and various chemicals, which were proposed to be due to acid-base interactions. Among the chemicals used were various naphthenic acids. Synthesised monodisperse acids gave a reduction of

  8. Effect of asphaltenes on crude oil wax crystallization

    DEFF Research Database (Denmark)

    Kriz, Pavel; Andersen, Simon Ivar

    2005-01-01

    The paper summarizes the experimental work done on asphaltene influenced wax crystallization. Three different asphaltenes (from stable oil, instable oil, and deposit) were mixed at several concentrations or dispersions into the waxy crude oil. These blends were evaluated by viscometry and yield...... stress measurement and compared with the original crude oil. A complex asphaltene−wax interaction as a function of asphaltene concentration and degree of asphaltene dispersion under dynamic and static condition was observed. The crystallization and the wax network strength was strongly dependent...... influence the wax crystallization at static condition more significantly than the more flocculated....

  9. Effect of asphaltenes on crude oil wax crystallization

    DEFF Research Database (Denmark)

    Kriz, Pavel; Andersen, Simon Ivar

    2005-01-01

    The paper summarizes the experimental work done on asphaltene influenced wax crystallization. Three different asphaltenes (from stable oil, instable oil, and deposit) were mixed at several concentrations or dispersions into the waxy crude oil. These blends were evaluated by viscometry and yield...... stress measurement and compared with the original crude oil. A complex asphaltene−wax interaction as a function of asphaltene concentration and degree of asphaltene dispersion under dynamic and static condition was observed. The crystallization and the wax network strength was strongly dependent...... influence the wax crystallization at static condition more significantly than the more flocculated....

  10. Isolation of Asphaltene-Degrading Bacteria from Sludge Oil

    Directory of Open Access Journals (Sweden)

    Pingkan Aditiawati

    2015-03-01

    Full Text Available Sludge oil contains 30%–50% hydrocarbon fractions that comprise saturated fractions, aromatics, resins, and asphaltene. Asphaltene fraction is the most persistent fraction. In this research, the indigenous bacteria that can degrade asphaltene fractions from a sludge oil sample from Balikpapan that was isolated using BHMS medium (Bushnell-Hass Mineral Salt with 0.01% (w/v yeast extract, 2% (w/v asphaltene extract, and 2% (w/v sludge oil. The ability of the four isolates to degrade asphaltene fractions was conducted by the biodegradation asphaltene fractions test using liquid cultures in a BHMS medium with 0.01% (w/v yeast extract and 2% (w/v asphaltene extract as a carbon source. The parameters measured during the process of biodegradation of asphaltene fractions include the quantification of Total Petroleum Hydrocarbon (g, log total number of bacteria (CFU/ml, and pH. There are four bacteria (isolates 1, 2, 3, and 4 that have been characterized to degrade asphaltic fraction and have been identified as Bacillus sp. Lysinibacillus fusiformes, Acinetobacter sp., and Mycobacterium sp., respectively. The results showed that the highest ability to degrade asphaltene fractions is that of Bacillus sp. (isolate 1 and Lysinibacillus fusiformes (Isolate 2, with biodegradation percentages of asphaltene fractions being 50% and 55%, respectively, and growth rate at the exponential phase is 7.17x107 CFU/mL.days and 4.21x107 CFU/mL.days, respectively.

  11. Interaction Mechanism of Oil-in-Water Emulsions with Asphaltenes Determined Using Droplet Probe AFM.

    Science.gov (United States)

    Shi, Chen; Zhang, Ling; Xie, Lei; Lu, Xi; Liu, Qingxia; Mantilla, Cesar A; van den Berg, Frans G A; Zeng, Hongbo

    2016-03-15

    Emulsions with interface-active components at the oil/water interface have long been of fundamental and practical interest in many fields. In this work, the interaction forces between two oil droplets in water in the absence/presence of asphaltenes were directly measured using droplet probe atomic force microscopy (AFM) and analyzed using a theoretical model based on Reynolds lubrication theory and the augmented Young-Laplace equation by including the effects of disjoining pressure. It was revealed that the interaction forces measured between two pristine oil droplets (i.e., toluene) could be well described by the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, while an additional steric interaction should be included in the presence of asphaltenes in the oil. The surface interaction and the stability of oil droplets in aqueous solution were demonstrated to be significantly influenced by the asphaltenes concentration in oil, salt concentration, pH, and presence of divalent ions (Ca(2+)) in water. Adsorbed asphaltenes at the oil/water interface led to more negative surface potential of the oil/water interface and also induced steric repulsion between oil droplets, inhibiting the drop coalescence and stabilizing the oil-in-water emulsion. Lower pH of aqueous solution could lead to less negative surface potential and weaken the repulsion between oil droplets. Addition of divalent ions (Ca(2+)) was found to disrupt the protecting effects of adsorbed asphaltenes at oil/water interface and induce coalescence of oil droplets. Our results provide a useful methodology for quantifying the interaction forces and investigating the properties of asphaltenes at the oil/water interfaces and provide insights into the stabilization mechanism of oil-in-water emulsions due to asphaltenes in oil production and water treatment.

  12. Structural Study of Asphaltenes from Iranian Heavy Crude Oil

    Directory of Open Access Journals (Sweden)

    Davarpanah L.

    2015-11-01

    Full Text Available In the present study, asphaltene precipitation from Iranian heavy crude oil (Persian Gulf off-shore was performed using n-pentane (n-C5 and n-heptane (n-C7 as light alkane precipitants. Several analytical techniques, each following different principles, were then used to structurally characterize the precipitated asphaltenes. The yield of asphaltene obtained using n-pentane precipitant was higher than asphaltene precipitated with the use of n-heptane. The asphaltene removal affected the n-C5 and n-C7 maltene fractions at temperatures below 204°C, as shown by the data obtained through the simulated distillation technique. Viscosity of heavy oil is influenced by the asphaltene content and behavior. The viscosity dependence of the test heavy oil on the shear rate applied was determined and the flow was low at y. above 25 s-1 . The reconstituted heavy oil samples were prepared by adding different amounts of asphaltenes to the maltenes (deasphalted heavy oil and asphaltene effects were more pronounced at the low temperature of 25°C as compared with those at the higher temperatures. According to the power law model used in this study the flowability of the test heavy oil exhibited a pseudoplastic character. Structural results obtained from Fourier Transform InfraRed (FTIR spectroscopy showed the presence of the different functional groups in the precipitated asphaltenes. For instance, the presence of different hydrocarbons (aliphatic, aromatic and alicyclic based on their characteristics in the FTIR spectra was confirmed. Resins are effective dispersants, and removal of this fraction from the crude oil is disturbing to the colloidal nature of heavy oil; asphaltene flocculation and precipitation eventually occur. Appearance of pores in the Scanning Electron Microscopy (SEM images was used as an indicator of the resin detachment. With the use of 1H and 13C Nuclear Magnetic Resonance (NMR spectroscopy, two important structural parameters of the

  13. Heavy Oil Process Monitor: Automated On-Column Asphaltene Precipitation and Re-Dissolution

    Energy Technology Data Exchange (ETDEWEB)

    John F. Schabron; Joseph F. Rovani; Mark Sanderson

    2007-03-31

    An automated separation technique was developed that provides a new approach to measuring the distribution profiles of the most polar, or asphaltenic components of an oil, using a continuous flow system to precipitate and re-dissolve asphaltenes from the oil. Methods of analysis based on this new technique were explored. One method based on the new technique involves precipitation of a portion of residua sample in heptane on a polytetrafluoroethylene-packed (PTFE) column. The precipitated material is re-dissolved in three steps using solvents of increasing polarity: cyclohexane, toluene, and methylene chloride. The amount of asphaltenes that dissolve in cyclohexane is a useful diagnostic of the thermal history of oil, and its proximity to coke formation. For example, about 40 % (w/w) of the heptane asphaltenes from unpyrolyzed residua dissolves in cyclohexane. As pyrolysis progresses, this number decrease to below 15% as coke and toluene insoluble pre-coke materials appear. Currently, the procedure for the isolation of heptane asphaltenes and the determination of the amount of asphaltenes soluble in cyclohexane spans three days. The automated procedure takes one hour. Another method uses a single solvent, methylene chloride, to re-dissolve the material that precipitates on heptane on the PTFE-packed column. The area of this second peak can be used to calculate a value which correlates with gravimetric asphaltene content. Currently the gravimetric procedure to determine asphaltenes takes about 24 hours. The automated procedure takes 30 minutes. Results for four series of original and pyrolyzed residua were compared with data from the gravimetric methods. Methods based on the new on-column precipitation and re-dissolution technique provide significantly more detail about the polar constituent's oils than the gravimetric determination of asphaltenes.

  14. Asphaltene and solids-stabilized water-in-oil emulsions

    Science.gov (United States)

    Sztukowski, Danuta M.

    Water-in-crude oil emulsions are a problem in crude oil production, transportation, and processing. Many of these emulsions are stabilized by asphaltenes and native oilfield solids adsorbed at the oil-water interface. Design of effective emulsion treatments is hampered because there is a lack of understanding of the role asphaltenes and solids play in stabilizing these emulsions. In this work, the structural, compositional and rheological properties of water/hydrocarbon interfaces were determined for model emulsions consisting of water, toluene, heptane, asphaltenes and native oilfield solids. The characteristics of the interface were related to the properties of asphaltenes and native solids. Emulsion stability was correlated to interfacial rheology. A combination of vapour pressure osmometry, interfacial tension and emulsion gravimetric studies indicated that asphaltenes initially adsorb at the interface as a monolayer of self-associated molecular aggregates. It was demonstrated why it is necessary to account for asphaltene self-association when interpreting interfacial measurements. The interfacial area of Athabasca asphaltenes was found to be approximately 1.5 nm2 and did not vary with concentration or asphaltene self-association. Hence, more self-associated asphaltenes simply formed a thicker monolayer. The interfacial monolayer observed in this work varied from 2 to 9 nm in thickness. The asphaltene monolayer was shown to adsorb reversibly only at short interface aging times. The film gradually reorganizes at the interface to form a rigid, irreversibly adsorbed network. The elastic and viscous moduli can be modeled using the Lucassen-van den Tempel (LVDT) model when the aging time is less than 10 minutes. An increase in film rigidity can be detected with an increase in the total elastic modulus. Increased film rigidity was shown to reduce the rate of coalescence in an emulsion and increase overall emulsion stability (reduce free water resolution). The rate of

  15. Asphaltenes molecular modeling of Boscan crude oil

    Energy Technology Data Exchange (ETDEWEB)

    Kowalewski, I.; Vandenbroucke, M.; Behar, F.; Huc, A.Y. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France); Faulon, J.L. [Sandia National Labs., Albuquerque, NM (United States); Taylor, M.J.

    1996-01-01

    The asphaltenes presence in the petrochemical feedstocks can disturb a lot some refining processes. In this context, some molecular models have been carried out to better understand the chemical structures of these asphaltenes molecules. The aim of this work is to estimate for the asphaltenes molecules the molecular models potentialities by the use of crystal structure elucidation programs (XMOL and SIGNATURE softwares) and by molecular simulation (INSIGHT II/DISCOVER softwares). In particular, two models of Boscan asphaltenes covalent molecules with intense reticulation degrees are discussed. (O.L.). 29 refs., 6 figs., 6 tabs.

  16. Enhanced Oil Recovery (EOR by Miscible CO2 and Water Flooding of Asphaltenic and Non-Asphaltenic Oils

    Directory of Open Access Journals (Sweden)

    Edwin A. Chukwudeme

    2009-09-01

    Full Text Available An EOR study has been performed applying miscible CO2 flooding and compared with that for water flooding. Three different oils are used, reference oil (n-decane, model oil (n-C10, SA, toluene and 0.35 wt % asphaltene and crude oil (10 wt % asphaltene obtained from the Middle East. Stearic acid (SA is added representing a natural surfactant in oil. For the non-asphaltenic oil, miscible CO2 flooding is shown to be more favourable than that by water. However, it is interesting to see that for first years after the start of the injection (< 3 years it is shown that there is almost no difference between the recovered oils by water and CO2, after which (> 3 years oil recovery by gas injection showed a significant increase. This may be due to the enhanced performance at the increased reservoir pressure during the first period. Maximum oil recovery is shown by miscible CO2 flooding of asphaltenic oil at combined temperatures and pressures of 50 °C/90 bar and 70 °C/120 bar (no significant difference between the two cases, about 1% compared to 80 °C/140 bar. This may support the positive influence of the high combined temperatures and pressures for the miscible CO2 flooding; however beyond a certain limit the oil recovery declined due to increased asphaltene deposition. Another interesting finding in this work is that for single phase oil, an almost linear relationship is observed between the pressure drop and the asphaltene deposition regardless of the flowing fluid pressure.

  17. Waxes in asphaltenes of crude oils and wax deposits

    Directory of Open Access Journals (Sweden)

    Yulia M. Ganeeva

    2016-07-01

    Full Text Available Abstract Composition and molecular mass distribution of n-alkanes in asphaltenes of crude oils of different ages and in wax deposits formed in the borehole equipment were studied. In asphaltenes, n-alkanes from C12 to C60 were detected. The high molecular weight paraffins in asphaltenes would form a crystalline phase with a melting point of 80–90 °C. The peculiarities of the redistribution of high molecular paraffin hydrocarbons between oil and the corresponding wax deposit were detected. In the oils, the high molecular weight paraffinic hydrocarbons C50–C60 were found, which were not practically detected in the corresponding wax deposits.

  18. Chemical composition of asphaltenes of crude oil from Baradero field in Cuba

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Proskuryakov, V.A.; Klyavina, O.A.; Kolyabina, N.A. [L.N. Tolstoi Tula State Pedagogical Institute (Russian Federation)

    1994-09-10

    Asphaltenes of crude oil from Baradero field in Cuba have been studied by physical and physicochemical methods. Dynamics of distribution of nitrogen, sulfur, and oxygen and also various functional groups in asphaltenes has been described. These data can be used for the proper deasphalting of crude oil and further treatment of asphaltenes.

  19. Comparisons Between Asphaltenes from the Dead and Live-Oil Samples of the Same Crude Oils

    DEFF Research Database (Denmark)

    Aquino-Olivos, M.A.; Andersen, Simon Ivar; Lira-Galeana, C.

    2003-01-01

    Asphaltenes precipitated from pressure-preserve bottomhole oil samples have been obtained for three oils at different pressures, using a bulk high-pressure filtration apparatus. The precipitates captured on the filter were recovered, the asphaltenes defined by the n-heptane insolubility were extr...

  20. Thin film pyrolysis of oil sands asphaltenes for structural analysis

    Energy Technology Data Exchange (ETDEWEB)

    Karimi, Arash; Gray, Murray R [Department of Chemical and Materials Engineering, University of Alberta (Canada); Qian, Kuangnan; Olmstead, William N.; Freund, Howard [ExxonMobil Research and Engineering (United States)], email: murray.gray@ualberta.ca

    2010-07-01

    Current methods to extract asphaltene building blocks only produce small sample quantities per batch for analysis. To reach sample quantities sufficient for several analytical methods on each batch, the following method was investigated in a preliminary study. Asphaltenes from Alberta bitumen were spray coated as thin films on alloy plates to be used in controlled pyrolysis. Each batch of six plates reacted around 1 g of asphaltenes in the furnace. Reaction products were purged from the reaction chamber with cold nitrogen, then cooled in a cold trap. Gases were collected and analysed using gas chromatography. Liquid products were condensed in a cold trap, rinsed with solvent, and evaporated overnight. The coke was also recovered from the plates and analysed. The method yielded mass balances greater than 90%. Products analysis revealed molecular fragment sizes ranging from C10 to C100. Lighter components (C5-C10) were not detected, having probably evaporated during solvent removal.

  1. Asphaltenes in Mexican fuel oils; Asfaltenos en combustoleos mexicanos

    Energy Technology Data Exchange (ETDEWEB)

    Longoria Ramirez, Rigoberto [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1996-12-31

    In this article the main aspects in which the Instituto de Investigaciones Electricas (IIE) has worked to contribute to the solution of problems due to the presence of asphaltenes in national fuel oils, are emphasized. The increment of these compounds, that concentrate harmful elements, in the last ten years has reached 22% by weight of the fuel oil. It is demonstrated that the quantification of asphaltenes depends on the type of solvent employed. [Espanol] En este articulo se subrayan los principales aspectos en los que el Instituto de Investigaciones Electricas (IIE) ha trabajado para contribuir a la solucion de problemas debidos a la presencia de asfaltenos en combustoleos nacionales. El incremento de estos compuestos, que concentran elementos nocivos, en los ultimos diez anos ha llegado hasta un 22% del peso del combustoleo. Se demuestra que la cuantificacion de los asfaltenos depende del tipo de solvente utilizado.

  2. Precipitation, fractionation and characterization of asphaltenes from heavy and light crude oils

    Energy Technology Data Exchange (ETDEWEB)

    F. Trejo; G. Centeno; J. Ancheyta [Instituto Mexicano del Petroleo, Mexico (Mexico). Programa de Tratamiento de Crudo Maya

    2004-11-01

    Asphaltenes of Maya and Isthmus crude oils were precipitated, fractionated and characterized in this work. Isolation of asphaltenes was performed by following the ASTM D3279 method, which uses n-heptane for solvent precipitation. Asphaltenes were separated into three fractions by Soxhlet extraction with a binary solvent system of toluene and n-heptane. C, H, O, N, S, and Ni and V contents were determined in asphaltenes and in their fractions by elemental analysis and atomic absorption, respectively. VPO aggregate weight and NMR measurements were also performed in all samples. Important differences in properties of unfractionated asphaltenes and asphaltenes fractions were observed. Some of these differences were attributed to impurities in the unfractionated asphaltenes. 26 refs., 5 figs., 2 tabs.

  3. Interfacial and colloidal behavior of asphaltenes obtained from Brazilian crude oils

    Energy Technology Data Exchange (ETDEWEB)

    Carlos da Silva Ramos, Antonio; Haraguchi, Lilian; Mohamed, Rahoma S. [School of Chemical Engineering, Universidade Estadual de Campinas C.P. 6066, SP Campinas (Brazil); Notrispe, Fabio R.; Loh, Watson [Institute of Chemistry, Universidade Estadual de Campinas, SP Campinas (Brazil)

    2001-12-29

    In this work, we present new data on the interfacial and colloidal behavior of asphaltenes in model aromatic solvents and crude oils and discuss the implications of these data on the aggregation, adsorption on solid surfaces, inhibition of deposition and emulsion stabilization capacities for two types of asphaltenes obtained from Brazilian crude oils. Surface tension measurements in solutions formed by any of these two types of asphaltenes, pentane insolubles (C5I) or heptane insolubles (C7I), in aromatic solvents suggested the occurrence of an aggregation phenomenon of asphaltenes in each of the solvents studied. Viscosity measurements in these same solutions revealed yet another type of aggregation at higher asphaltene concentrations. Both aggregation processes were found to be a function of temperature and type of asphaltenes. For the asphaltenes investigated, C7I was always more prone to aggregation, a characteristic ascribed to its higher asphaltene and lower resin content as revealed by SARA chromatographic analysis, and to its larger average molecular weight as determined by VPO. The effect of temperature on these two processes confirmed the exothermic nature of both. A number of block copolymers, ionic and non-ionic surfactants, were tested for their effectiveness as asphaltenes stabilizers in crude oil. The results revealed different and distinct mechanisms for solubilization/dispersion of asphaltenes in aromatic (aliphatic) solvents and for the inhibition of asphaltene precipitation in crude oils. The two types of asphaltenes (C5I and C7I) were found to be effective in the stabilization of water/oil emulsions as well as water/toluene emulsions, with larger effects for C7I in water/toluene emulsions, consistent with its greater surface activity and its larger tendency to self-associate. Finally, the interaction of asphaltenes with solid surfaces was evaluated by determining the adsorption isotherms of asphaltenes on silica and activated carbon. The organic

  4. Molecular dynamic simulation of asphaltene co-aggregation with humic acid during oil spill.

    Science.gov (United States)

    Zhu, Xinzhe; Chen, Daoyi; Wu, Guozhong

    2015-11-01

    Humic acid in water and sediment plays a key role in the fate and transport of the spilled oil, but little is known about its influence on the aggregation of heavy oil asphaltenes which is adverse for remediation. Molecular dynamic simulation was performed to characterize the co-aggregation of asphaltenes (continental model and Violanthrone-79 model) with Leonardite humic acid (LHA) at the toluene-water interface and in bulk water, respectively, to simulate the transport of asphaltenes from oil to water. At the toluene-water interface, a LHA layer tended to form and bind to the water by hydrogen bonding which provided a surface for the accumulation of asphaltenes by parallel or T-shape stacking. After entering the bulk water, asphaltene aggregates stacked in parallel were tightly sequestrated inside the inner cavity of LHA aggregates following surface adsorption and structure deformation. Asphaltene aggregation in water was 2-fold higher than at the toluene-water interface. The presence of LHA increased the intensity of asphaltene aggregation by up to 83% in bulk water while relatively less influence was observed at the toluene-water interface. Overall results suggested that the co-aggregation of asphaltene with humic acid should be incorporated to the current oil spill models for better interpreting the overall environmental risks of oil spill. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Evaluating the hydrophilic-lipophilic nature of asphaltenic oils and naphthenic amphiphiles using microemulsion models.

    Science.gov (United States)

    Kiran, Sumit K; Acosta, Edgar J; Moran, Kevin

    2009-08-01

    Asphaltenes and naphthenic acid derivatives, which are polar and surface-active species, are known to interfere with the recovery of heavy crude oil by promoting the formation of stable emulsions. In this study, previously established microemulsion phase behavior models were applied to quantify the hydrophilic-lipophilic nature of asphaltenic oils (bitumen, deasphalted bitumen, asphalt, naphthalene) and surface-active species found in heavy oils (naphthenic compounds and asphaltenes). For the test oils, the equivalent alkane carbon number (EACN) was determined by evaluating the "salinity shifts" of microemulsions formulated with a reference surfactant (sodium dihexyl sulfosuccinate--SDHS) and a reference oil (toluene) as a function of test oil volume fraction. Similarly, the characteristic curvature (C(C)) of surface-active species was determined by evaluating the salinity shifts as a function of the molar fraction of the surface-active species in mixture with SDHS. As a part of the oil phase, asphaltenes and asphaltene-like species are highly hydrophilic, which lead to low EACN values despite their large molecular weight. As a surface-active material, asphaltenes are hydrophobic species that lead to the formation of water-in-oil emulsions. Naphthenates, particularly sodium naphthenates, are highly hydrophilic compounds that lead to the formation of oil-in-water emulsions. These hydrophilic-lipophilic characterization parameters, and the methods used to determine them, can be used in the future to understand the phase behavior of complex oil-water systems.

  6. An FTIR method for the analysis of crude and heavy fuel oil asphaltenes to assist in oil fingerprinting.

    Science.gov (United States)

    Riley, Brenden J; Lennard, Chris; Fuller, Stephen; Spikmans, Val

    2016-09-01

    A proof-of-concept spectroscopic method for crude and heavy fuel oil asphaltenes was developed to complement existing methods for source determination of oil spills. Current methods rely on the analysis of the volatile fraction of oils by Gas Chromatography (GC), whilst the non-volatile fraction, including asphaltenes, is discarded. By discarding the non-volatile fraction, important oil fingerprinting information is potentially lost. Ten oil samples representing various geographical regions were used in this study. The asphaltene fraction was precipitated from the oils using excess n-pentane, and analysed by Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR). Based on visual interpretation of FTIR spectra along with peak height ratio comparisons, all ten oil samples could be differentiated from one another. Furthermore, ATR-FTIR was not able to differentiate a weathered crude oil sample from its source sample, demonstrating significant potential for the application of asphaltenes in oil fingerprinting.

  7. Sorption and distribution of asphaltene, resin, aromatic and saturate fractions of heavy crude oil on quartz surface: molecular dynamic simulation.

    Science.gov (United States)

    Wu, Guozhong; He, Lin; Chen, Daoyi

    2013-09-01

    The molecular scale sorption, diffusion and distribution of asphaltene, resin, aromatic and saturate fractions of heavy crude oil on quartz surface were studied using molecular dynamic simulation. Sorption of saturates on quartz decreased by 31% when temperature increased from 298 to 398K while opposite trend was observed for resins, but insignificant changes were found in asphaltenes and aromatics. Despite of this variety, the main contribution of interactions was van der Waals energy (>90%) irrespective of molecular components and temperatures. The diffusion coefficient of saturates was predicted as 10.8×10(-10)m(2)s(-1) while that of the remaining fractions was about 4×10(-10)m(2)s(-1) at 298K. The most likely oil distribution on quartz surface was that aromatics and saturates transported randomly into and out of the complex consisting of asphaltenes surrounded by resins, which was influenced by temperature. Overall, the knowledge on quartz-oil and oil-oil interactions gained in this study is essential for future risk assessment and remediation activities as previous studies on soil remediation either limited to light oil fractions with <40 carbons or treated the heavy crude oil as a single pseudo entity ignoring the interactions between oil fractions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. The effect of asphaltene-paraffin interactions on crude oil stability

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M.C. del; Carbogani, L. [PDVSA, Caracas (Venezuela)

    2000-08-01

    The effect of asphaltene-paraffin complexes on crude oil stability, in terms of wax crystallization and asphaltene deposits solubility, was studied. The influence of flocculated asphaltenes on the wax crystallization tendency of a paraffinic crude oil was evaluated by means of Polarized Light Microscopy. Heavy linear paraffins (nC24+ paraffins) were added to the crude oil in a controlled fashion in order to evaluate its effect on the cloud point and the effectiveness of a maleic anhydride copolymer derivative paraffin inhibitor. Experiments done in the presence and absence of asphaltene fraction allowed to demonstrate that flocculated asphaltenes provide wax crystallization sites whose presence increases the cloud point of crude oil and also interferes with crystal inhibition mechanism. The existence of asphaltene-paraffins complexes and some structural effects were further assessed by HPLC kinetic dissolution studies of composite materials formed by combinations of such hydrocarbon types. Commercial macrocrystalline and microcrystalline waxes were used in these experiments. Different types of asphaltenes were probed as well, covering varying ranges of aromaticities and stability. (au)

  9. Investigating Asphaltenes Composition in Crude Oil Samples using ...

    African Journals Online (AJOL)

    MBI

    2015-12-22

    Dec 22, 2015 ... asphaltene recovered by precipitation is analogous to Iatroscan analysis carried out prior to ... tagged 8676 was observed to comparatively have higher asphaltene composition (1125 mg, 11.22 %) than its ... increase in molecular weight, density, viscosity, .... developed in another mobile phase made up of.

  10. Using the biomarker bonded on the asphaltenes for biodegraded oil-source correlation

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Ruthenium-ion-catalyzed oxidation (RICO) has been used to investigate asphaltenes from three oils with the same origin in the Juquan Basin and three oils with the same origin but with different degree of biodegradation in the Turpan Basin, Northwest China. The preliminary results showed that the biomarkers bonded on the asphaltenes with the same origin is similar and is correlated with the free biomarker in saturates. The bonded biomarkers have no relationship with the biodegradation. An application on the severely biodegraded oils is reported here. The biomarker and benzenecarboxylic methyl esters reflecting the structure of the asphaltenes after RICO should provide a new way for oil-source correlation and it should be specially useful for severely biodegraded oil-source correlation.

  11. Upgrading fuzzy logic by GA-PS to determine asphaltene stability in crude oil

    Directory of Open Access Journals (Sweden)

    Saeid Ahmadi

    2017-06-01

    Full Text Available Precipitation and deposition of asphaltene are undesirable phenomena that arise during petroleum production which give rise to a pronounced rate of increase in operational cost and adversely affect production rates as well. Hence, it is imperative to develop a mathematical model for the assessment of asphaltene stability in crude oil. In the present study, delta RI which constitutes the difference between refractive index of crude oil (RI and refractive index of crude oil at the onset of asphaltene precipitation (PRI is employed as the principal factor for determining the asphaltene stability of the region. Fuzzy logic is a potent tool capable of extracting the underlying dependency between SARA fractions (saturate, aromatic, resin, and asphaltene data and delta RI for the inexpensive and rapid diagnosis of asphaltene stability. In this study a novel strategy known as hybrid genetic algorithm-pattern search (GA-PS is suggested for the development of an optimal fuzzy logic model as a reliable alternative for the widely-applied subtractive clustering (SC method. While SC solely optimizes mean of input Gaussian membership functions (GMFs, GA-PS tool optimizes both mean and variance of input GMFs. Comparison between GA-PS and SC methods confirmed the capability of GA-PS for developing an optimal fuzzy logic model.

  12. Preparation and characterization of a composite membrane based on the asphaltene component of coal

    Institute of Scientific and Technical Information of China (English)

    Zhang Liying; Qin Zhihong; Li Xinyan; Chen Juan; Liu Peng; Wang Xiaoyan

    2011-01-01

    Asphaltene-ceramic composite membranes were fabricated from ceramic supports and an asphaltene component,which was obtained from the separation of coal to give a kind of new carbonaceous precursor material.Using SEM and thermogravimetric analysis to measure the microstructure and properties of the asphaltene component allowed the porosity,permeability,and retention ratios to be determined.The results show that the asphaltene component can be regarded as a good carbon membrane precursor material because of its high carbon content and strong bonding capacity.When ceramic supports are impregnated with asphaltene colloid the asphaltene easily combines with the support surface and forms a good carbonaceous film after carbonization.Little of the asphaltene component permeates into the internal pores of the ceramic support.Although the number of coats applied to the substrate had little affect on the porosity of the asphaltene-ceramic composite membranes the permeability varied depending upon the number of times the substrate was treated.The way bubbles escape from the film.and the phenomenon of coalescence,as affected by different film thicknesses also seem closely related to the number of coats.A composite membrane carbonized at a final temperature of 600 ℃ is relatively dense and the permeability of Fe(OH)3 colloid through it is very low.A membrane fired at 800 ℃ is porous and its permeability and retention of Fe(OH)3 colloid are 88 L/(m2 h MPa) and 85.3%,respectively when the trans-membrane pressure is 0.22 MPa.

  13. Athabasca asphaltene structures

    Energy Technology Data Exchange (ETDEWEB)

    Dettman, H.; Salmon, S.; Zinz, D. [National Centre for Upgrading Technology, Devon, AB (Canada)

    2009-07-01

    In order to model petroleum behaviour during production and refining processes, it is important to understand the molecular character of oil components. Gas chromatography can be used to separate components with boiling points less than 524 degrees C. However, since asphaltenes have a higher boiling point, gel permeation chromatography (GPC) must be used to separate species before analysis. Analysis of Athabasca asphaltene GPC fractions has shown that asphaltenes consist of 2 types of species, notably crunchy species that are graphitic in appearance, and oily species. The molecular weights range from 400 to 2000 g/mole as measured by low resolution mass spectrometry. This poster described the ongoing effort to separate the asphaltenes by polarity. Athabasca asphaltenes were subfractioned into 4 parts according to differential solubility in pentane and centrifugation. Acidic species were isolated from the asphaltenes using adsorption chromatography. The 4 polarity fractions and acid species have been characterized with particular reference to elemental and metals content. Analyses were performed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) carbon type analyses. This poster provided comparisons of their elution profiles by GPC. tabs., figs.

  14. Molecular Dynamics Simulation: The Behavior of Asphaltene in Crude Oil and at the Oil/Water Interface

    KAUST Repository

    Gao, Fengfeng

    2014-12-18

    Carboxyl asphaltene is commonly discussed in the petroleum industry. In most conditions, electroneutral carboxyl asphaltene molecules can be deprotonated to become carboxylate asphaltenes. Both in crude oil and at the oil/water interface, the characteristics of anionic carboxylate asphaltenes are different than those of the carboxyl asphaltenes. In this paper, molecular dynamics (MD) simulations are utilized to study the structural features of different asphaltene molecules, namely, C5 Pe and anionic C5 Pe, at the molecular level. In crude oil, the electroneutral C5 Pe molecules prefer to form a steady face-to-face stacking, while the anionic C5 Pe molecules are inclined to form face-to-face stacking and T-shaped II stacking because of the repulsion of the anionic headgroups. Anionic C5 Pe has a distinct affinity to the oil/water interface during the simulation, while the C5 Pe molecules persist in the crude oil domain. A three-stage model of anionic C5 Pe molecules adsorbed at the oil/water interface is finally developed.

  15. The zeta potential and surface properties of asphaltenes obtained with different crude oil/n-heptane proportions

    Energy Technology Data Exchange (ETDEWEB)

    Hilda Parra-Barraza; Daniel Hernandez-Montiel; Jaime Lizardi; Javier Hernandez; Ronaldo Herrera Urbina; Miguel A. Valdez [Universidad de Sonora, Sonora (Mexico). Departamento de Ciencias Quimico Biologicas

    2003-05-01

    We have investigated some surface properties of asphaltenes precipitated from crude oil with different volumes of n-heptane. According to the crude oil/n-heptane proportions used, asphaltenes are identified as 1:5, 1:15 and 1:40. Zeta potential results indicate that the amount of n-heptane determines the electrokinetic behaviour of asphaltenes in aqueous suspensions. Asphaltene 1:5 exhibits an isoelectric point (IEP) at pH 4.5 whereas asphaltenes 1:15 and 1:40 show an IEP at about pH 3. Surface charge on asphaltenes arises from the dissociation of acid functionalities and the protonation of basic functional groups. The presence of resins remaining on the asphaltene molecules may be responsible for the different IEP of asphaltene 1:5. Both sodium dodecyl sulfate (an anionic surfactant) and cetylpyridinium chloride (a cationic surfactant) were found to adsorb specifically onto asphaltenes. They reverse the sign of the zeta potential under certain conditions. These surfactants may be potential candidates to aid in controlling the stability of crude oil dispersions. Critical micelle concentration, interfacial tension measurements, and Langmuir isotherms at the air water interface confirm the different nature of asphaltene 1:5, which also showed more solubility and a larger molecular size. 26 refs., 3 figs., 1 tab.

  16. Small angle neutron scattering (SANS and V-SANS) study of asphaltene aggregates in crude oil.

    Science.gov (United States)

    Headen, Thomas F; Boek, Edo S; Stellbrink, Jörg; Scheven, Ulrich M

    2009-01-06

    We report small angle neutron scattering (SANS) experiments on two crude oils. Analysis of the high-Q SANS region has probed the asphaltene aggregates in the nanometer length scale. We find that the radius of gyration decreases with increasing temperature. We show that SANS measurements on crude oils give similar aggregate sizes to those found from SANS measurements of asphaltenes redispersed in deuterated toluene. The combined use of SANS and V-SANS on crude oil samples has allowed the determination of the radius of gyration of large scale asphaltene aggregates of approximately 0.45 microm. This has been achieved by the fitting of Beaucage functions over two size regimes. Analysis of the fitted Beaucage functions at very low-Q has shown that the large scale aggregates are not simply made by aggregation of all the smaller nanoaggregates. Instead, they are two different aggregates coexisting.

  17. Structural Characterisation of Asphaltenes during Residue Hydrotreatment with Light Cycle Oil as an Additive

    Directory of Open Access Journals (Sweden)

    Yong-Jun Liu

    2015-01-01

    Full Text Available Several atmospheric residues (AR of Kuwaiti crude, in the absence, or in the presence, of light cycle oil (LCO as an aromatic additive, were hydrotreated in an experimental plant. Asphaltenes (precipitated from Kuwaiti AR, a hydrotreated AR, and a hydrotreated blend of AR and LCO were characterised by chemical structure and changes during residue hydrotreatment. The average structural parameters of these asphaltenes, obtained from a combined method of element analysis, average molecular weight, X-ray diffraction, and NMR, demonstrate that, after hydrotreatment, the aromatic cores of the asphaltenes become more compact and smaller whereas the peripheral alkyl branches are decreased in number and shortened. The influence of LCO on residue hydrotreating is also studied in terms of structural changes in the asphaltenes. The findings imply that LCO added to AR during hydrotreating improves the degree of aromatic substitution, the total hydrogen/carbon atomic ratio per average molecule, the distance between aromatic sheets and aliphatic chains, and so forth, by modifying the colloidal nature and microstructure of asphaltene: this is beneficial for the further hydroprocessing of AR. Three hypothetical average molecules are proposed to represent the changes undergone by such asphaltenes during hydrotreatment as well as the effects of additive LCO.

  18. A new thermodynamic model for the prediction of asphaltene precipitation in crude oil

    Directory of Open Access Journals (Sweden)

    Alireza Fazlali

    2010-01-01

    Full Text Available It has been proved that asphaltene precipitation is a difficult problem to define and study. Precipitation of these complex and heavy organic compounds can cause serious problems in crude oil production and transportation, residual oil processing and heavy oil combustion. Several theories have been proposed to explain the mechanism of asphaltenes precipitation. The Flory-Huggins (F-H is one of the famous models, which are used to describe the asphaltene precipitation mechanisms in the same ways as polymeric solutions. In this research, the F-H model has been modified to predict the phasebehavior of asphaltene precipitation process during adding non-polar (normal alkane solvents. The adjustable parameters of this model are computed by using a least-square approach between the modeling results and experimental data. Then, the results of these models are compared with the obtained results of the original F-H and the experimental data at different conditions. According to the interaction parameter as an adjustable parameter, four new functionalities have been used for this target. According to the obtained results, the modified model with a second order equation can predict the amount of asphaltene precipitation better than the others with a minimum error. The calculation shows good agreement between theexperimental data and the results of the modified model.

  19. The fractal aggregation of asphaltenes.

    Science.gov (United States)

    Hoepfner, Michael P; Fávero, Cláudio Vilas Bôas; Haji-Akbari, Nasim; Fogler, H Scott

    2013-07-16

    This paper discusses time-resolved small-angle neutron scattering results that were used to investigate asphaltene structure and stability with and without a precipitant added in both crude oil and model oil. A novel approach was used to isolate the scattering from asphaltenes that are insoluble and in the process of aggregating from those that are soluble. It was found that both soluble and insoluble asphaltenes form fractal clusters in crude oil and the fractal dimension of the insoluble asphaltene clusters is higher than that of the soluble clusters. Adding heptane also increases the size of soluble asphaltene clusters without modifying the fractal dimension. Understanding the process of insoluble asphaltenes forming fractals with higher fractal dimensions will potentially reveal the microscopic asphaltene destabilization mechanism (i.e., how a precipitant modifies asphaltene-asphaltene interactions). It was concluded that because of the polydisperse nature of asphaltenes, no well-defined asphaltene phase stability envelope exists and small amounts of asphaltenes precipitated even at dilute precipitant concentrations. Asphaltenes that are stable in a crude oil-precipitant mixture are dispersed on the nanometer length scale. An asphaltene precipitation mechanism is proposed that is consistent with the experimental findings. Additionally, it was found that the heptane-insoluble asphaltene fraction is the dominant source of small-angle scattering in crude oil and the previously unobtainable asphaltene solubility at low heptane concentrations was measured.

  20. Interfacial rheology of asphaltenes at oil-water interfaces and interpretation of the equation of state.

    Science.gov (United States)

    Rane, Jayant P; Pauchard, Vincent; Couzis, Alexander; Banerjee, Sanjoy

    2013-04-16

    In an earlier study, oil-water interfacial tension was measured by the pendant drop technique for a range of oil-phase asphaltene concentrations and viscosities. The interfacial tension was found to be related to the relative surface coverage during droplet expansion. The relationship was independent of aging time and bulk asphaltenes concentration, suggesting that cross-linking did not occur at the interface and that only asphaltene monomers were adsorbed. The present study extends this work to measurements of interfacial rheology with the same fluids. Dilatation moduli have been measured using the pulsating droplet technique at different frequencies, different concentrations (below and above CNAC), and different aging times. Care was taken to apply the technique in conditions where viscous and inertial effects are small. The elastic modulus increases with frequency and then plateaus to an asymptotic value. The asymptotic or instantaneous elasticity has been plotted against the interfacial tension, indicating the existence of a unique relationship, between them, independent of adsorption conditions. The relationship between interfacial tension and surface coverage is analyzed with a Langmuir equation of state. The equation of state also enabled the prediction of the observed relationship between the instantaneous elasticity and interfacial tension. The fit by a simple Langmuir equation of state (EOS) suggests minimal effects of aging and of nanoaggregates or gel formation at the interface. Only one parameter is involved in the fit, which is the surface excess coverage Γ∞ = 3.2 molecules/nm(2) (31.25 Å(2)/molecule). This value appears to agree with flat-on adsorption of monomeric asphaltene structures consisting of aromatic cores composed of an average of six fused rings and supports the hypothesis that nanoaggregates do not adsorb on the interface. The observed interfacial effects of the adsorbed asphaltenes, correlated by the Langmuir EOS, are consistent with

  1. Modeling of asphaltene particle deposition from turbulent oil flow in tubing: Model validation and a parametric study

    Directory of Open Access Journals (Sweden)

    Peyman Kor

    2016-12-01

    Full Text Available The deposition of asphaltenes on the inner wall of oil wells and pipelines causes flow blockage and significant production loss in these conduits. The major underlying mechanism(s for the deposition of asphaltene particles from the oil stream are still under investigation as an active research topic in the literature. In this work, a new deposition model considering both diffusional and inertial transport of asphaltene toward the tubing surface was developed. Model predictions were compared and verified with two sound experimental data available in the literature to evaluate the model's performance. A parametric study was done using the validated model in order to investigate the effect of the asphaltene particle size, flow velocity and oil viscosity on the magnitude of asphaltene deposition rate. Results of the study revealed that increasing the oil velocity causes more drag force on wall's inner surface; consequently, particles tend to transport away from the surface and the rate of asphaltene deposition is decreased. In addition, the developed model predicts that at low fluid velocity (∼0.7 m/s, the less viscous oil is more prone to asphaltene deposition problem.

  2. Characterization of asphaltene molecular structures by cracking under hydrogenation conditions and prediction of the viscosity reduction from visbreaking of heavy oils

    Science.gov (United States)

    Rueda Velasquez, Rosa Imelda

    The chemical building blocks that comprise petroleum asphaltenes were determined by cracking samples under conditions that minimized alterations to aromatic and cycloalkyl groups. Hydrogenation conditions that used tetralin as hydrogen-donor solvent, with an iron-based catalyst, allowed asphaltenes from different geological regions to yield 50-60 wt% of distillates (recovery of cracking products and characterization of the distillates, by gas chromatography-field ionization--time of flight high resolution mass spectrometry, displayed remarkable similarity in molecular composition for the different asphaltenes. Paraffins and 1-3 ring aromatics were the most abundant building blocks. The diversity of molecules identified, and the high yield of paraffins were consistent with high heterogeneity and complexity of molecules, built up by smaller fragments attached to each other by bridges. The sum of material remaining as vacuum residue and coke was in the range of 35-45 wt%; this total represents the maximum amount of large clusters in asphaltenes that could not be converted to lighter compounds under the evaluated cracking conditions. These analytical data for Cold Lake asphaltenes were transformed into probability density functions that described the molecular weight distributions of the building blocks. These distributions were input for a Monte Carlo approach that allowed stochastic construction of asphaltenes and simulation of their cracking reactions to examine differences in the distributions of products associated to the molecular topology. The construction algorithm evidenced that a significant amount of asphaltenes would consist of 3-5 building blocks. The results did not show significant differences between linear and dendritic molecular architectures, but suggested that dendritic molecules would experience slower reaction rates as they required more breakages to reach a given yield of distillates. Thermal cracking of asphaltenes in heavy oils and bitumens can

  3. Model molecules mimicking asphaltenes.

    Science.gov (United States)

    Sjöblom, Johan; Simon, Sébastien; Xu, Zhenghe

    2015-04-01

    Asphalthenes are typically defined as the fraction of petroleum insoluble in n-alkanes (typically heptane, but also hexane or pentane) but soluble in toluene. This fraction causes problems of emulsion formation and deposition/precipitation during crude oil production, processing and transport. From the definition it follows that asphaltenes are not a homogeneous fraction but is composed of molecules polydisperse in molecular weight, structure and functionalities. Their complexity makes the understanding of their properties difficult. Proper model molecules with well-defined structures which can resemble the properties of real asphaltenes can help to improve this understanding. Over the last ten years different research groups have proposed different asphaltene model molecules and studied them to determine how well they can mimic the properties of asphaltenes and determine the mechanisms behind the properties of asphaltenes. This article reviews the properties of the different classes of model compounds proposed and present their properties by comparison with fractionated asphaltenes. After presenting the interest of developing model asphaltenes, the composition and properties of asphaltenes are presented, followed by the presentation of approaches and accomplishments of different schools working on asphaltene model compounds. The presentation of bulk and interfacial properties of perylene-based model asphaltene compounds developed by Sjöblom et al. is the subject of the next part. Finally the emulsion-stabilization properties of fractionated asphaltenes and model asphaltene compounds is presented and discussed.

  4. Asphaltene dispersants as demulsification aids

    Energy Technology Data Exchange (ETDEWEB)

    Manek, M.B.

    1995-11-01

    Destabilization of petroleum asphaltenes may cause a multitude of problems in crude oil recovery and production. One major problem is their agglomeration at the water-oil interface of crude oil emulsions. Once agglomeration occurs, destabilized asphaltenes can form a thick pad in the dehydration equipment, which significantly reduces the demulsification rate. Certain polymeric dispersants increase asphaltene solubilization in hydrocarbon media, and when used in conjunction with emulsion breakers, facilitate the demulsification process. Two case studies are presented that demonstrate how asphaltene dispersants can efficiently inhibit pad formation and help reduce demulsifier dosage. Criteria for dispersant application and selection are discussed, which include the application of a novel laboratory technique to assess asphaltene stabilization in the crude oil. The technique monitors asphaltene agglomeration while undergoing titration with an incompatible solvent (precipitant). The method was used to evaluate stabilization of asphaltenes in the crude oil and to screen asphaltene dispersants.

  5. Composting and vermicomposting experiences in the treatment and bioconversion of asphaltens from the Prestige oil spill.

    Science.gov (United States)

    Martín-Gil, Jesús; Navas-Gracia, Luís Manuel; Gómez-Sobrino, Ernesto; Correa-Guimaraes, Adriana; Hernández-Navarro, Salvador; Sánchez-Báscones, Mercedes; del Carmen Ramos-Sánchez, María

    2008-04-01

    This work illustrates the effectiveness of composting and vermicomposting in degrading fuel-in-water emulsions from oil spills (chapapote), and the isolation of potentially useful microorganisms for its biodegradation. Firstly, an alternative to the biodegradation of asphaltens from the Prestige oil spill (still present in some chapapote rafts in the Cantabrian coast) by means of the application of composting techniques to a microbial partnership acclimated to fuel-oil is offered. Our aim is that, after a relatively short period of time, the microorganisms can obtain its source of carbon and energy from asphaltens. The addition of metabolic co-substrates, like cow bed and potato peelings, allows the fragmentation of complex compounds into smaller structures, susceptible to further degradation. Afterwards, a maturation of the compost by means of a treatment with earthworms (Eisenia foetida) is necessary. Thus, through the vermicomposting it will be possible to obtain a valued product, useful in the processes of ground amendment, with little presence of asphaltens and occluded polycyclic aromatic hydrocarbons, rich in humus, and with an important bacterial flora of Bacillus genera, so that it can be typical of co-activators and accelerating products in composting processes. Along with this article, we show some parameters that control the evolution of the compost products (evolved gases, acidity, temperature and humidity); the chemical and microbiological analytical results; and the germination assays of vermicomposting. Results reveal that by using microorganisms living in either earthworm intestines (Stenotrophomonas maltophilia) or vermiculture substrates (Scedosporium apiospermium), it is possible to degrade and to eliminate the polycyclic asphaltens into CO(2) and H(2)O, helped by evaporation, dissolution and/or photo-oxidation processes. The obtained end product has contents of interesting vegetal nutrients and, mainly, it displays very high germination indices.

  6. Effect on molecular interactions of chemical alteration of petroleum asphaltenes. I

    DEFF Research Database (Denmark)

    Juyal, Priyanka; Garcia, Daniel Merino; Andersen, Simon Ivar

    2005-01-01

    Asphaltenes are naturally occurring components of crude oil and have been the subject of many studies that have involved a variety of methods to determine their complex structure, their association in crude oil with resins, and their agglomeration phenomena. Yet, the molecular structures of aspha......Asphaltenes are naturally occurring components of crude oil and have been the subject of many studies that have involved a variety of methods to determine their complex structure, their association in crude oil with resins, and their agglomeration phenomena. Yet, the molecular structures...... these fractions. Experimental data from isothermal titration calorimetry has been used in assessing the role of polar hydrogen bonding functionalities in self-association of these complex molecules. Stability characteristics of these altered asphaltenes have further been studied by onset flocculation titration...... asphaltenes in crude oil. It has been inferred that the stability of these asphaltenes in crude oil definitely can be related to the extent of intrinsic polarity....

  7. Evaluation of hydrotreating reaction time of Furrial crude oil for improvement of asphaltene and their fractions in p-nitrophenol

    Energy Technology Data Exchange (ETDEWEB)

    Luis, M.A. [Univ. de Carabobo, Estado Carabobo (Venezuela, Bolivarian Republic of). Dept. de Quimica, Laboratorio de Catalisis y Metales de Transicion; Villasana, Y. [Univ. de Carabobo, Estado Carabobo (Venezuela, Bolivarian Republic of). Dept. de Quimica, Laboratorio de Catalisis y Metales de Transicion; Univ. de Carabobo, Estado Carabobo (Venezuela, Bolivarian Republic of). Dept. de Quimica, Grupo de Petroleo, Hidrocarburo y Derivados; Labrador, H. [Univ. de Carabobo, Estado Carabobo (Venezuela, Bolivarian Republic of). Dept. de Quimica, Grupo de Petroleo, Hidrocarburo y Derivados

    2008-07-01

    This study evaluated the hydrotreating (HDT) reaction time of Furrial crude oil using NiMoS/g- Al2O3 as a catalyst. The objective was to improve asphaltene and their fractions obtained by the p-nitrophenol method. The reaction conditions in terms of temperature, pressure and stirring times in the batch reactor were presented. Two hydrotreating reactions were conducted without catalysts at 6 and 8 hours under the same conditions in order to compare the effect of the catalyst on the asphaltene. In addition, 2 other reactions were conducted in which the catalysts were varied. The hydrotreated asphaltene was precipitated with n-heptane, and was later fractionated using the p-nitrophenol method (PNP). Two fractions were obtained. One was insoluble in toluene, while the other was a soluble fraction. Nuclear magnetic resonance and elemental analysis of C, H, N and S were used to characterize the asphaltene obtained in each reaction along with their fractions. The optimum reaction time was 6 hours. The asphaltene was as stable as the original and was predominantly aliphatic with less nitrogen and sulphur content. The hydrotreating reactions without a catalyst did not improve the asphaltene characteristic.

  8. Investigation of some solvents for asphalten-wax-paraffin depositions formed on the oil refinery equipment

    Directory of Open Access Journals (Sweden)

    О. В. Тертишна

    2013-07-01

    Full Text Available Тhe methods of asphalten - wax- paraffin depositions removal from the oil refinery equipment were studied. The effectiveness of solvents were estimated by mass losses of samples wrapped up in filter paper after exposition in different reagents, such as once-run petrol, benzene, toluene, hexane and some mixtures of these substances. The best results were obtained in the hexane - benzene mixture with volume ratio 1:1. The maximal level of dissolution was achieved at 30-35 °С

  9. Definition of asphaltenes

    Energy Technology Data Exchange (ETDEWEB)

    Speight, J.G. (Exxon Research and Engineering, Co., Linden, NJ); Long, R.B.; Trowbridge, T.D.

    1982-01-01

    Asphaltenes have been defined by various methods, but these methods are almost always based on a method of separation or purification of the materials. This paper provides a selective review of the methods which have been employed for the determination of asphaltenes in petroleum, heavy oils, bitumens, and residua; and the applications of these methods to Athabasca bitumen is described. The influence of the method of separation on the molecular weight of the asphaltenes is examined in detail, and the effects on the variations in recommended procedures are noted. Thus it is obvious that asphaltenes are not only a complex chemical fraction but a complex physical fraction that is difficult to define. (BLM)

  10. Colloidal analysis of the asphaltene and their fractions with p-nitrophenol (PNP) of the Furrial crude oil for effect of the hydrotreating to different pressures

    Energy Technology Data Exchange (ETDEWEB)

    Labrador-Sanchez, H. [Univ. de Carabobo, Estado Carabobo (Venezuela, Bolivarian Republic of). Dept. de Quimica, Grupo de Petroleo, Hidrocarburo y Derivados; Lindarte, L. [Univ. de Carabobo, Estado Carabobo (Venezuela, Bolivarian Republic of). Dept. de Quimica, Grupo de Petroleo, Hidrocarburo y Derivados; Univ. de Carabobo, Estado Carabobo (Venezuela, Bolivarian Republic of). Dept. de Quimica, Laboratorio de Catalisis y Metales de Transicion; Luis, M.A. [Univ. de Carabobo, Estado Carabobo (Venezuela, Bolivarian Republic of). Dept. de Quimica, Laboratorio de Catalisis y Metales de Transicion

    2008-07-01

    A study was conducted to investigate the effect of hydrotreating Furrial crude oil on asphaltene and its fractions (A1 and A2) obtained by the p-Nitrophenol (PNP) method. A batch reactor was used at different pressures of hydrogen to perform 8 hydrotreating reactions on the Furrial crude oil. Asphaltenes were separated from the oil and fractioned with PNP to obtain A1 and A2. The asphaltene and their fractions were characterized for flocculation threshold, percentage of total sulfur, nuclear magnetic resonance of 13C and elemental composition. The study showed that hydrotreating influenced the colloidal behaviour of the asphaltene and that the catalyst promoted the conversion of asphaltene, its stability, and its desulfurization. Hydrotreating had a greater affect on the A2 fraction than the A1 fraction. 2 refs.

  11. Methods of making carbon fiber from asphaltenes

    Energy Technology Data Exchange (ETDEWEB)

    Bohnert, George; Bowen, III, Daniel E.

    2017-02-28

    Making carbon fiber from asphaltenes obtained through heavy oil upgrading. In more detail, carbon fiber is made from asphaltenes obtained from heavy oil feedstocks undergoing upgrading in a continuous coking reactor.

  12. Carbon isotopic compositions of 1,2,3,4-tetramethylbenzene in marine oil asphaltenes from the Tarim Basin: Evidence for the source formed in a strongly reducing environment

    Institute of Scientific and Technical Information of China (English)

    JIA WangLu; PENG PingAn; XIAO ZhongYao

    2008-01-01

    Although 1-alkyl-2,3,6-trimethylbenzenes and a high relative amount of 1,2,3,4-tetramethylbenzene have been detected in marine oils and oil asphaltenes from Tabei uplift in the Tarim Basin, their biological sources are not determined. This paper deals with the molecular characteristics of typical marine oil asphaltenes from Tabei and Tazhong uplift in the Tarim Basin and the stable carbon isotopic signatures of individual compounds in the pyrolysates of these asphaltenes using flash pyrolysis-gas chromatograph-mass spectrometer (PY-GC-MS) and gas chromatograph-stable isotope ratio mass spectrometer (GC-C-IRMS), respectively. Relatively abundant 1,2,3,4-tetramethylbenzene is detected in the pyrolysates of these marine oil asphaltenes from the Tarim Basin. δ13C values of 1,2,3,4-tetramethylbenzene in the pyrolysates of oil asphaltenes vary from -19.6‰ to -24.0‰, while those of n-alkanes in the pyrolysates show a range from -33.2‰ to -35.1‰. The 1,2,3,4-tetramethylbenzene in the pyrolysates of oil asphaltenes proves to be significantly enriched in 13C relative to n-alkanes in the pyrolysates and oil asphaltenes by 10.8‰-15.2%. and 8.4‰-13.4‰, respectively. This result indicates a contribution from photosynthetic green sulfur bacteria Chlorobiaceae to relatively abundant 1,2,3,4-tetramethylbenzene in marine oil asphaltenes from the Tarim Basin. Hence, it can be speculated that the source of most marine oil asphaltenes from the Tarim Basin was formed in a strongly reducing water body enriched in H2S under euxinic conditions.

  13. Charge dependent asphaltene adsorption onto metal substrate : electrochemistry and AFM, STM, SAM, SEM analysis

    Energy Technology Data Exchange (ETDEWEB)

    Batina, N.; Morales-Martinez, J. [Univ. Autonoma Metropolitana-Iztapalapa (Mexico). Lab. de Nanotecnologia e Ingenieria Molecular; Ivar-Andersen, S. [Technical Univ. of Denmark (Denmark). Dept. Hem. Eng; Lira-Galeana, C. [Inst. Mexicano del Petroleo, Lazaro (Mexico). Molecular Simulation Research Program; De la Cruz-Hernandez, W.; Cota-Araiza, L.; Avalos-Borja, M. [Univ. Nacional Autonoma de Mexico (Mexico)

    2008-07-01

    Asphaltenes have been identified as the main component of pipeline molecular deposits that cause plugging of oil wells. In this study, Atomic Force Microscopy (AFM), Scanning Tunneling Microscopy (STM), Scanning Auger Microprobe Spectroscopy (SAM) and Scanning Electron Microscopy (SEM) were used to characterized molecular deposits of Mexican crude oil and asphaltenes formed at a charged metal surface. The qualitative and quantitative characterization involved determining the size and shape of adsorbed molecules and aggregates, and the elemental analysis of all components in molecular films. Samples were prepared by electrolytic deposition under galvanostatic or potentiostatic conditions directly from the crude oil or asphaltene in toluene solutions. The study showed that the formation of asphaltene deposit depends on the metal substrate charge. Asphaltenes as well as crude oil readily adsorbed at the negatively charged metal surface. Two elements were present, notably carbon and sulfur. Their content ratio varied depending on the metal substrate charge.

  14. Extraction and characterization of crude oil asphaltenes sub fractions; Extracao e caracterizacao de subfracoes de asfaltenos de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Silas R.; Calado, Lucas S.; Honse, Siller O.; Mansur, Claudia R.E.; Lucas, Elizabete F., E-mail: silas@ima.ufrj.br [Universidade Federal do Rio de Janeiro, Instituto de Macromoleculas, Laboratorio de Macromoleculas e Coloides na Industria de Petroleo, Rio de Janeiro, RJ (Brazil)

    2011-07-01

    Asphaltenes from crude oil have been studied for a long time. However, until today their chemical structures and physical-chemical properties are not well established. Nowadays, it is accepted that asphaltenes are dispersed in the crude oil as macro structures, which are mainly constituted of some condensed aromatic rings (about 6-20), containing aliphatic or naphthenic groups. The asphaltenes are also defined as the crude oil fraction that is insoluble in low molar mass n-alkanes and soluble in aromatic solvents, like benzene and toluene In order to investigate the molecular structure, in this work the asphaltenes were separated by using a different procedure as that normally described in the literature and characterized by infrared spectrometry, nuclear magnetic resonance, x-ray fluorescence, elemental analyses and particle size and size distribution. The difference in subfractions polarity can be attributed not only to the aromaticity changes but also to the content of elements, such as N, O, Fe, V, Si e Ni. (author)

  15. Enhancing the Effectiveness of Carbon Dioxide Flooding by Managing Asphaltene Precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Deo, Milind D.

    2002-02-21

    This project was undertaken to understand fundamental aspects of carbon dioxide (CO2) induced asphaltene precipitation. Oil and asphaltene samples from the Rangely field in Colorado were used for most of the project. The project consisted of pure component and high-pressure, thermodynamic experiments, thermodynamic modeling, kinetic experiments and modeling, targeted corefloods and compositional modeling.

  16. Hydrogen bonding in asphaltenes and coal. Quarterly Report for July 1, 1978 - September 30, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Li, N.C.; Tewari, K.C.

    1978-09-29

    Two coal liquid products derived from the same Kentucky hvAb coal have been separated into toluene-insoluble, asphaltene, and pentane-soluble heavy oil fractions. Viscosity and calorimetric studies are reported of the interaction between heavy oil and asphaltene(A) and its acid/neutral(AA) and base(BA) components in solvent benzene. The increase in viscosity and molar enthalpy of interaction, {Delta}H{sup 0}, in the order BA>A>AA, correlate well with the proton magnetic resonance downfield chemical shift of the OH signal of o-phenylphenol, as a function of added asphaltene (A, AA, BA) concentration in solvent CS{sub 2}· The results suggest that when asphaltene .and heavy oil are present together, hydrogen-bonding involving largely phenolic OH, is one of the mechanisms by which asphaltene-heavy oil interactions are achieved and, in part, is responsible for the viscosity increase of coal liquids.

  17. Study of flow properties of asphaltenic oils in a porous medium; Etude des proprietes d`ecoulement des bruts asphalteniques en milieu poreux

    Energy Technology Data Exchange (ETDEWEB)

    Petrova-Bensalem, R.

    1998-06-30

    Deposits of asphaltenes during production can adversely affect the exploitation of certain fields, that of Hassi Messaoud is a known example. The objective of this study is essentially focused on the damage aspects due to formation of this deposits. A methodology has been developed which makes it possible to determine the flow properties of asphaltenic oils in a porous medium under conditions close to those of a reservoir and to detect the formation of organic deposits in situ. Several types of rocks with different morphology were selected along with a number of asphaltenic oils having varied geographic origins. It was shown with these that it was possible to evaluate, in laboratory, the reduction in permeability to the oil resulting from an asphaltene deposit during the circulation of crude oil in the samples. It was observed that the variation in blocking the cores as a function of the volume of injected fluid is similar to the blocking kinetics ascertained for the retention of solid suspended particles in injection water. This similarity in the phenomena led to using particle damage models developed for the latter case. Several experiments involving blocking by asphaltenes could thus be satisfactory simulated, showing that this approach is worth developing despite the differences between the two types of colloidal suspension. The method using injection or `squeeze` of co- solvents was studied with the same systems (rock/crude oil) as a possible remedy for asphaltene deposition. To select suitable solvents and additives. A methodology was established based on application of Hansen`s theory for adjusting the polarity of solvent to the chemical properties of the asphaltene to be eliminated. This was combined with a series of in vitro tests with separated asphaltenes and the minerals of the reservoir rock. The efficiency of the co-solvents thus selected was verified by slug injection in to cores which has been damaged by asphaltenes. This approach may well help the

  18. Effect of demulsifiers on interfacial films and stability of water-in-oil emulsions stabilized by asphaltenes

    Energy Technology Data Exchange (ETDEWEB)

    Baydak, E.N.; Yarranton, H.W.; Ortiz, D. [Calgary Univ., AB (Canada). Dept. of Chemical and Petroleum Engineering; Moran, K. [Syncrude Research Centre, Edmonton, AB (Canada)

    2008-07-01

    In water-in-toluene/heptane emulsions stabilized by asphaltenes, there is a correlation between emulsion stability and the compressibility of interfacial asphaltene films. In order to determine if this correlation for emulsion stability is more generally applicable, a study was conducted in which the effect of commercial demulsifiers on the film properties and emulsion stability was measured. A naphthenic acid (NA) and a branched dodecylbenzene sulfonic acid (DDBS) were examined. Surface pressure isotherms were measured in a drop shape analyzer for droplets of asphaltenes, toluene, and heptane surrounded by a solution of water and surfactant. The experimental variables included heptane, asphaltene and surfactant concentration along with aging time. The compressibilities of the interfacial films were determined from the slope of the surface pressure isotherms. Water-in-oil emulsions were prepared from the same solutions. Emulsion stability was evaluated in terms of the free water evolved after a treatment of centrifugation and heating. Initial results suggest that the demulsifiers increase the compressibility of the interfacial films. In most cases, the addition of the demulsifier increased emulsion stability. The timing of the addition of the demulsifier or the phase to which it was added did not appear to have an influence on the results. It was concluded that the reduction in interfacial tension from the added surfactant may inhibit coalescence more than the weakening of the interfacial film promotes coalescence. 1 ref.

  19. Enthalpies of hydrogen bonding of quinoline with o-phenylphenol and of hydrogen-bonding reactions involving the acid and base components of a coal-derived asphaltene

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, A.G.; Blaha, C.; Li, N.C.

    1977-01-01

    Calorimetric studies are reported of hydrogen bonding between quinoline (Qu) and o-phenylphenol (OPP). The enthalpies of hydrogen-bonding of the acid and base components of a coal-derived asphaltene with OPP and Qu are also reported. The results provide strong evidence that the acid and base components of asphaltene function substantially as hydrogen donor and acceptor, respectively. 1 figure, 1 table.

  20. Modeling of Asphaltene Precipitation from Crude Oil with the Cubic Plus Association Equation of State

    DEFF Research Database (Denmark)

    Arya, Alay; Liang, Xiaodong; von Solms, Nicolas

    2017-01-01

    to calculate the asphaltene onset condition during the addition of different n-paraffin precipitants (n-pentane to n-hexadecane). Three parameters per precipitant are fitted to calculate the asphaltene yield during the addition of the precipitant. The results obtained from the model are compared...

  1. Ruthenium-ion-catalyzed oxidation of asphaltenes and oil-source correlation of heavy oils from the Lunnan and Tahe oilfields in the Tarim Basin, NW China

    Institute of Scientific and Technical Information of China (English)

    MA Anlai; ZHANG Shuichang; ZHANG Dajiang; JIN Zhijun; MA Xiaojuan; CHEN Qingtang

    2005-01-01

    The identification of marine source rocks in the Tarim Basin is debated vigorously. The intention of this paper is to investigate the asphaltenes in heavy oils from the Lunnan and Tahe oilfields and Well TD2 with ruthenium-ions-catalyzed oxidation technique (RICO), in order to explore its role in oil-oil and oil-source correlations. The RICO products included n-alkanoic acids, α, ω-di-n-alkanoic acids, branched alkanoic acids, tricyclic terpanoic acids, hopanoic acids, gammacerane carboxylic acid , regular sterane carboxylic acids and 4-methylsterane carboxylic acids. The n-alkyl chains and biomarkers bounded on the asphaltenes were of unsusceptibility to biodegradation. The distribution and absolute concentrations of n-alkanoic acids in the RICO products of heavy oils from the Lunnan and Tahe oilfields are different from those of Well TD2. The biomarkers bounded on the asphaltenes, especially steranes, have a distribution trend similar to that of the counterparts in saturates. The sterane carboxylic acids and 4-methylsterane carboxylic acids in the RICO products of heavy oils from the Lunnan and Tahe oilfields, dominated by C30 sterane and C31 4-methylsterane carboxylic acids, respectively, are significantly different from those of the heavy oils of Well TD2, whose dominating sterane and 4-methylsterane carboxylic acids are C2s sterane and C29 4-methylsterane acids, respectively. The RICO products of the asphaltenes further indicate that the Middle-Upper Ordovician may be the main source rocks for heavy oils from the Lunnan and Tahe oilfields.

  2. Interfacial properties of asphaltenes at toluene-water interfaces.

    Science.gov (United States)

    Zarkar, Sharli; Pauchard, Vincent; Farooq, Umer; Couzis, Alexander; Banerjee, Sanjoy

    2015-05-05

    Asphaltenes are "n-alkane insoluble" species in crude oil that stabilize water-in-oil emulsions. To understand asphaltene adsorption mechanisms at oil-water interfaces and coalescence blockage, we first studied the behavior in aliphatic oil-water systems in which asphaltenes are almost insoluble. They adsorbed as monomers, giving a unique master curve relating interfacial tension (IFT) to interfacial coverage through a Langmuir equation of state (EoS). The long-time surface coverage was independent of asphaltene bulk concentration and asymptotically approached the 2-D packing limit for polydisperse disks. On coalescence, the surface coverage exceeded the 2-D limit and the asphaltene film appeared to become solidlike, apparently undergoing a transition to a soft glassy material and blocking further coalescence. However, real systems consist of mixtures of aliphatic and aromatic components in which asphaltenes may be quite soluble. To understand solubility effects, we focus here on how the increased bulk solubility of asphaltenes affects their interfacial properties in comparison to aliphatic oil-water systems. Unlike the "almost irreversible" adsorption of asphaltenes where the asymptotic interfacial coverage was independent of the bulk concentration, an equilibrium surface pressure, dependent on bulk concentration, was obtained for toluene-water systems because of adsorption being balanced by desorption. The equilibrium surface coverage could be obtained from the short- and long-term Ward-Tordai approximations. The behavior of the equilibrium surface pressure with the equilibrium surface coverage was then derived. These data for various asphaltene concentrations were used to determine the EoS, which for toluene-water could also be fitted by the Langmuir EoS with Γ∞ = 3.3 molecule/nm(2), the same value as that found for these asphaltenes in aliphatic media. Asphaltene solubility in the bulk phase only appears to affect the adsorption isotherm but not the Eo

  3. Interaction of oil components and clay minerals in reservoir sandstones

    Energy Technology Data Exchange (ETDEWEB)

    Changchun Pan; Linping Yu; Guoying Sheng; Jiamo Fu [Chinese Academy of Sciences, State Key Lab. of Organic Geochemistry, Wushan, Guangzhou (China); Jianhui Feng; Yuming Tian [Chinese Academy of Sciences, State Key Lab. of Organic Geochemistry, Wushan, Guangzhou (China); Zhongyuan Oil Field Co., Puyang, Henan (China); Xiaoping Luo [Zhongyuan Oil Field Co., Puyang, Henan (China)

    2005-04-15

    The free oil (first Soxhlet extract) and adsorbed oil (Soxhlet extract after the removal of minerals) obtained from the clay minerals in the <2 {mu}m size fraction as separated from eight hydrocarbon reservoir sandstone samples, and oil inclusions obtained from the grains of seven of these eight samples were studied via GC, GC-MS and elemental analyses. The free oil is dominated by saturated hydrocarbons (61.4-87.5%) with a low content of resins and asphaltenes (6.0-22.0% in total) while the adsorbed oil is dominated by resins and asphaltenes (84.8-98.5% in total) with a low content of saturated hydrocarbons (0.6-9.5%). The inclusion oil is similar to the adsorbed oil in gross composition, but contains relatively more saturated hydrocarbons (16.87-31.88%) and less resins and asphaltenes (62.30-78.01% in total) as compared to the latter. Although the amounts of both free and adsorbed oils per gram of clay minerals varies substantially, the residual organic carbon content in the clay minerals of the eight samples, after the free oil extraction, is in a narrow range between 0.537% and 1.614%. From the decrease of the percentage of the extractable to the total of this residual organic matter of the clay minerals with burial depth it can be inferred that polymerization of the adsorbed polar components occurs with the increase of the reservoir temperature. The terpane and sterane compositions indicate that the oil adsorbed onto the clay surfaces appears to be more representative of the initial oil charging the reservoir than do the oil inclusions. This phenomenon could possibly demonstrate that the first oil charge preferentially interacts with the clay minerals occurring in the pores and as coatings around the grains. Although the variation of biomarker parameters between the free and adsorbed oils could be ascribed to the compositional changes of oil charges during the filling process and/or the differential maturation behaviors of these two types of oils after oil

  4. Mixture Effect on the Dilatation Rheology of Asphaltenes-Laden Interfaces.

    Science.gov (United States)

    Liu, Fang; Darjani, Shaghayegh; Akhmetkhanova, Nelya; Maldarelli, Charles; Banerjee, Sanjoy; Pauchard, Vincent

    2017-02-28

    Asphaltenes are a solubility class of crude oils comprising polyaromatic and heterocyclic molecules with different interfacial activities. The previously neglected effects of compositional mixture on dilatational rheology are discussed in the light of diffusional relaxation models. It is demonstrated that the reported deviations from the Lucassen-van den Tempel model for a single-component solution could largely originate from a distribution in adsorption coefficients within the asphaltenes class. This particularly applies to the peculiar gel point rheology previously ascribed to asphaltenes cross-linking at the interface. Furthermore, an extensive bibliographical review shows that asphaltenes dilatational rheology data always verify the main features of diffusional relaxation, including a decrease in modulus at high bulk concentrations and phase shift values always lower than 45°. Using diffusional relaxation concepts, the reanalysis of the most extensive dataset so far confirmed recently published studies, showing that asphaltenes exhibit a unique equation of state (EOS) irrespective of adsorption conditions. This EOS proves to be very similar for bitumen and petroleum asphaltenes. Finally, a numerical application of a binary diffusional model proved efficient to capture both dynamic interfacial tension and dilatational rheology, with the same parameters. It appears that a minority of asphaltenes (less than 10%) have a much stronger interfacial activity than the bulk of them, as previously demonstrated by fractionation. These results open up the need for a reinterpretation of the physical mechanisms of asphaltenes adsorption in terms of classical amphiphilic behavior, with a potential impact on emulsion breaking and enhanced oil recovery strategies.

  5. Revisiting the flocculation kinetics of destabilized asphaltenes.

    Science.gov (United States)

    Vilas Bôas Fávero, Cláudio; Maqbool, Tabish; Hoepfner, Michael; Haji-Akbari, Nasim; Fogler, H Scott

    2017-06-01

    A comprehensive review of the recently published work on asphaltene destabilization and flocculation kinetics is presented. Four different experimental techniques were used to study asphaltenes undergoing flocculation process in crude oils and model oils. The asphaltenes were destabilized by different n-alkanes and a geometric population balance with the Smoluchowski collision kernel was used to model the asphaltene aggregation process. Additionally, by postulating a relation between the aggregation collision efficiency and the solubility parameter of asphaltenes and the solution, a unified model of asphaltene aggregation model was developed. When the aggregation model is applied to the experimental data obtained from several different crude oil and model oils, the detection time curves collapsed onto a universal single line, indicating that the model successfully captures the underlying physics of the observed process. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Hydrogen bonding in asphaltenes and coal

    Energy Technology Data Exchange (ETDEWEB)

    Li, N.C.; Tewari, K.C.

    1978-04-01

    The objective of this program is to investigate and to determine the nature of hydrogen bonding and other molecular interactions that occur in asphaltene and coal liquids, and to seek possible correlations between the interactions and the viscosity. The asphaltene components of samples of centrifuged liquid product, CLP, and solvent-refined coal, SRC, supplied by the Pittsburgh Energy Research Center, are isolated by solvent fractionation. The compositions of the asphaltenes are obtained by elemental analysis and the molecular weights by vapor pressure osmometry. The acid/neutral and base components of the asphaltenes are separated and again elemental analysis and molecular weights are obtained. The magnetic resonance, infrared and calorimetric methods are used to determine the strength of hydrogen-bond and other molecular interactions in the fractions isolated. Investigations on the toluene-insoluble and heavy-oil fractions are also carried out. In addition, extensive proton magnetic resonance, near infrared and calorimetric studies are carried out for o-phenylphenol and quinoline, which serve as model compounds for the aromatic phenols and the heteronuclear aromatic base nitrogens, respectively, found in coal liquefaction products. This is the final report, giving a summary of activities under the Contract for the entire period.

  7. Atomistic modeling of oil shale kerogens and asphaltenes along with their interactions with the inorganic mineral matrix

    Energy Technology Data Exchange (ETDEWEB)

    Facelli, Julio [Univ. of Utah, Salt Lake City, UT (United States); Pugmire, Ronald [Univ. of Utah, Salt Lake City, UT (United States); Pimienta, Ian [Univ. of Utah, Salt Lake City, UT (United States)

    2011-03-31

    The goal of this project is to obtain and validate three dimensional atomistic models for the organic matter in both oil shales and oil sands. In the case of oil shales the modeling was completed for kerogen, the insoluble portion of the organic matter; for oil sands it was for asphaltenes, a class of molecules found in crude oil. The three dimensional models discussed in this report were developed starting from existing literature two dimensional models. The models developed included one kerogen, based on experimental data on a kerogen isolated from a Green River oil shale, and a set of six representative asphaltenes. Subsequently, the interactions between these organic models and an inorganic matrix was explored in order to gain insight into the chemical nature of this interaction, which could provide vital information in developing efficient methods to remove the organic material from inorganic mineral substrate. The inorganic substrate used to model the interaction was illite, an aluminum silicate oxide clay. In order to obtain the feedback necessary to validate the models, it is necessary to be able to calculate different observable quantities and to show that these observables both reproduce the results of experimental measurements on actual samples as well as that the observables are sensitive to structural differences between models. The observables that were calculated using the models include 13C NMR spectra, the IR vibrational spectra, and the atomic pair wise distribution function; these were chosen as they are among the methods for which both experimental and calculated values can be readily obtained. Where available, comparison was made to experiment results. Finally, molecular dynamic simulations of pyrolysis were completed on the models to gain an understanding into the nature of the decomposition of these materials when heated.

  8. Carbon isotopic compositions of 1,2,3,4-tetramethylbenzene in marine oil asphaltenes from the Tarim Basin:Evidence for the source formed in a strongly reducing environment

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Although 1-alkyl-2,3,6-trimethylbenzenes and a high relative amount of 1,2,3,4-tetramethylbenzene have been detected in marine oils and oil asphaltenes from Tabei uplift in the Tarim Basin, their bio-logical sources are not determined. This paper deals with the molecular characteristics of typical ma-rine oil asphaltenes from Tabei and Tazhong uplift in the Tarim Basin and the stable carbon isotopic signatures of individual compounds in the pyrolysates of these asphaltenes using flash pyrolysis-gas chromatograph-mass spectrometer (PY-GC-MS) and gas chromatograph-stable isotope ratio mass spectrometer (GC-C-IRMS), respectively. Relatively abundant 1,2,3,4-tetramethylbenzene is detected in the pyrolysates of these marine oil asphaltenes from the Tarim Basin. δ 13C values of 1,2,3,4-tetrame-thylbenzene in the pyrolysates of oil asphaltenes vary from-19.6‰ to-24.0‰, while those of n-alkanes in the pyrolysates show a range from-33.2‰ to-35.1‰. The 1,2,3,4-tetramethylbenzene in the pyro-lysates of oil asphaltenes proves to be significantly enriched in 13C relative to n-alkanes in the pyro-lysates and oil asphaltenes by 10.8‰―15.2‰ and 8.4‰―13.4‰, respectively. This result indicates a contribution from photosynthetic green sulfur bacteria Chlorobiaceae to relatively abundant 1,2,3,4-tetramethylbenzene in marine oil asphaltenes from the Tarim Basin. Hence, it can be speculated that the source of most marine oil asphaltenes from the Tarim Basin was formed in a strongly reducing water body enriched in H2S under euxinic conditions.

  9. Diagnosis of asphaltene stability in crude oil through “two parameters” SVM model

    DEFF Research Database (Denmark)

    Chamkalani, Ali; Mohammadi, Amir H.; Eslamimanesh, Ali

    2012-01-01

    is determined using the existing SARA fractions experimental data for this purpose. The powerful Least-Square modification of Support Vector Machine (LSSVM) strategy is applied to develop a computer program, by which the asphaltene stability region can be determined for various crudes. The developed two...

  10. Raman spectrum of asphaltene

    KAUST Repository

    Abdallah, Wael A.

    2012-11-05

    Asphaltenes extracted from seven different crude oils representing different geological formations from around the globe were analyzed using the Raman spectroscopic technique. Each spectrum is fitted with four main peaks using the Gaussian function. On the basis of D1 and G bands of the Raman spectrum, asphaltene indicated an ordered structure with the presence of boundary defected edges. The average aromatic sheet size of the asphaltene molecules is estimated within the range of 1.52-1.88 nm, which represents approximately seven to eight aromatic fused rings. This estimation is based on the integrated intensity of D1 and G bands, as proposed by Tunistra and Koenig. The results here are in perfect agreement with so many other used techniques and indicate the potential applicability of Raman measurements to determine the average aromatic ring size and its boundary. © 2012 American Chemical Society.

  11. Rheological properties of hydrate suspensions in asphaltenic crude oils; Proprietes rheologiques de suspensions d'hydrate dans des bruts asphalteniques

    Energy Technology Data Exchange (ETDEWEB)

    Marques de Toledo Camargo, R.

    2001-03-01

    The development of offshore oil exploitation under increasing water depths has forced oil companies to increase their understanding of gas hydrate formation and transportation in multiphase flow lines in which a liquid hydrocarbon phase is present. This work deals with the flow behaviour of hydrate suspensions in which a liquid hydrocarbon is the continuous phase. Three different liquid hydrocarbons are used: an asphaltenic crude oil, a condensate completely free of asphaltenes and a mixture between the asphaltenic oil and heptane. The rheological characterisation of hydrate suspensions is the main tool employed. Two original experimental devices are used: a PVT cell adapted to operate as a Couette type rheometer and a semi-industrial flow loop. Hydrate suspensions using the asphaltenic oil showed shear-thinning behaviour and thixotropy. This behaviour is typically found in flocculated systems, in which the particles attract each other forming flocs of aggregated particles at low shear rates. The suspensions using the condensate showed Newtonian behaviour. Their relative viscosities were high, which suggests that an aggregation process between hydrate particles takes. place during hydrate formation. Finally, hydrate suspensions using the mixture asphaltenic oil-heptane showed shear-thinning behaviour, thixotropy and high relative viscosity. From these results it can be inferred that, after the achievement of the hydrate formation process, the attractive forces between hydrate particles are weak. making unlikely pipeline obstruction by an aggregation process. Nevertheless, during the hydrate formation, these attractive forces can be sufficiently high. It seems that the hydrate surface wettability is an important parameter in this phenomena. (author)

  12. Hydrogen bonding study of quinoline and coal-derived asphaltene components with o-phenylphenol by proton magnetic resonance. [9 references

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, S.R.; Galya, L.G.; Brown, B.J.; Li, N.C.

    1976-01-01

    Proton magnetic resonance (PMR) studies are reported of hydrogen bonding between the OH proton of o-phenylphenol (OPP) and the nitrogen electron donor of quinoline (Qu). Data are also reported on the hydrogen bonding of a coal-derived asphaltene and its acid and base components with OPP. Determination was made of the equilibrium constants of the 1 : 1 complex between OPP and Qu at 39, 32, 1, and -18/sup 0/C from the PMR studies. Qualitative results are reported for the interaction between the base fraction of asphaltene and OPP at 32, 1, and -26/sup 0/C.

  13. Hydrogen bonding study of quinoline and coal-derived asphaltene components with o-phenylphenol by proton magnetic resonance. [9 refs

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, S.C.; Galya, L.G.; Brown, B.J.; Li, N.C.

    1976-01-01

    Proton magnetic resonance (PMR) studies are reported of hydrogen bonding between the OH proton of o-phenylphenol (OPP) and the nitrogen electron donor of quinoline (Qu). Data are also reported on the hydrogen bonding of a coal-derived asphaltene and its acid and base components with OPP. Determination was made of the equilibrium constants of the 1:1 complex between OPP and Qu at 39, 32, 1, and -18/sup 0/C from the PMR studies. Qualitative results are reported for the interaction between the base fraction of asphaltene and OPP at 32, 1, and -26/sup 0/C.

  14. Effect of asphaltene and resin oils on the viscosity of bituminous petroleum materials to be used as asphalt primers

    Directory of Open Access Journals (Sweden)

    Bencomo, M. R.

    2006-03-01

    Full Text Available The bituminous crude from the Machete, Venezuela, area, which has such a fluid consistency that it falls outside the normal scope of the A5TM D-5 (1 penetration test exceeding the 3D-mm ceiling specified in that standard and can be used as an asphalt primer: Like other asphalt products, these materials are -chemically speaking- a mix of numerous naphthenic, paraffinic and aromatic hydrocarbons and heterocyclic compounds containing sulphur, nitrogen, oxygen and so on. They have a dense and a malthene oil phase which, along with the natural hydrocarbons additives used in these products acts as a volatile fluidizer. The former is described as a mix of asphaltenes: complex high molecular weight substances that are insoluble in paraffinic hydrocarbons and soluble in aromatic compounds such as benzene. The malthene oil phase, in turn, consists in a mix of resins and hydrocarbons and together the two constitute a colloidal system. The experiments discussed in the present paper were conducted to determine the effect of the proportion of asphaltenes and resin oils on the viscosity of such bituminous crude emulsions/ with a view to their use as primers. These experiments were run in a Parr batch reactor in a nitrogen atmosphere using n-heptane as a solvent. The resins were separated after the asphaltenes precipitated from the samples and subsequently from the malthene fraction obtained. The results showed that the asphaltenes account for the structural characteristics and consistency of the medium and the resin oils for its cohesive properties/,the malthene oils act as solvents.Los crudos extrapesados procedentes del área Machete (Venezuela son materiales de consistencia blanda o fluida, por lo que se salen del campo en el que normalmente se aplica el ensayo de penetración a productos asfálticos según el método ASTM D-5 (1, cuyo límite máximo es 30 mm, y pueden ser utilizados como pinturas asfálticas de imprimación. Al igual que otros productos

  15. Polymeric dispersants delay sedimentation in colloidal asphaltene suspensions.

    Science.gov (United States)

    Hashmi, Sara M; Quintiliano, Leah A; Firoozabadi, Abbas

    2010-06-01

    Asphaltenes, among the heaviest components of crude oil, can become unstable under a variety of conditions and precipitate and sediment out of solution. In this report, we present sedimentation measurements for a system of colloidal scale asphaltene particles suspended in heptane. Adding dispersants to the suspension can improve the stability of the system and can mediate the transition from a power-law collapse in the sedimentation front to a rising front. Additional dispersant beyond a crossover concentration can cause a significant delay in the dynamics. Dynamic light scattering measurements suggest that the stabilization provided by the dispersants may occur through a reduction of both the size and polydispersity of the asphaltene particles in suspension.

  16. Evaluation of oil ducts wettability by measurements of contact angle. Effect of asphaltenes and naphtenic acids; Avaliacao da molhabilidade de oleodutos atraves de medidas de angulo de contato. Efeitos de asfaltenos e acidos naftenicos do petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Ronaldo G. dos; Mokamed, Rahoma S. [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Quimica; Loh, Watson [Universidade Estadual de Campinas, SP (Brazil). Inst. de Quimica

    2003-07-01

    The recent interest of the petroleum companies for heavy crude oils reserves have been increased in the last decades. Rheological properties of these oils interferes with their economical production and transportation. Technologies based on the flow of lubricated oil through an aqueous film (Core Flows) represent an alternative way to improve of the flow efficiency and viability of the recovery of these heavy oils. In the systems, the pressure drop caused from the high values of viscosity can be reduced to values similar to those encounter in single aqueous flow. The progressive accumulation oil on the pipeline walls is, however, the major problem for the implementation of core flow. For oil accumulation to take place, pipeline surface would need to be oil-wet. This work examines the wettability of pipeline surfaces and the effect of oil phase polar constitute such as asphaltenes and naphtenic acids in the possible alteration of these surfaces from water-wet to oil-wet. The effect of crude oil fractions on the wettability is shown by measurements of contact angle. Commercial and carbon steel are tested. The results show that the wettability of the surfaces depend on oil composition and can be rectified by components in aqueous phase. (author)

  17. Thermogravimetric assessment of thermal degradation in asphaltenes

    Energy Technology Data Exchange (ETDEWEB)

    Barneto, Agustín García, E-mail: agustin.garcia@diq.uhu.es [Department of Chemical Engineering, Physical Chemistry and Organic Chemistry, University of Huelva, Huelva (Spain); Carmona, José Ariza [Department of Chemical Engineering, Physical Chemistry and Organic Chemistry, University of Huelva, Huelva (Spain); Garrido, María José Franco [CEPSA, RDI Centre, Madrid (Spain)

    2016-03-20

    Graphical abstract: - Highlights: • Asphaltenes content of visbreaking streams in oil refinery can be measured by using TGA. • Deconvoluting TGA curves allows the thermal-based composition of asphaltenes to be elucidated. • Asphaltenes cracking involves acceleratory stages compatible with autocatalytic kinetic. • Activation energy during asphaltenes pyrolysis increased with increasing temperature. • Activation energy remained almost constant at 200–225 kJ/mol during oxidative cracking. - Abstract: Monitoring asphaltenes is very important with a view to optimizing visbreaking units in oil refineries. Current analyses based on selective dissolution in different solvents are slow, so new, more expeditious methods for measuring asphaltenes are required to facilitate fuel-oil production. In this work, we studied the thermal degradation of asphaltenes as the potential basis for a thermogravimetric method for their monitoring in visbreaking streams. The thermal degradation of asphaltenes occurs largely from 400 to 500 °C; the process is quite smooth in an inert environment but involves several fast mass loss events in the air. Kinetic parameters for characterizing the process were determined by using two model-free methods and the modified Prout–Tompkins kinetic equation to examine asphaltene thermolysis. Both types of methods showed the activation energy to increase during pyrolysis but to remain almost constant during cracking in the presence of oxygen or even diminish during char oxidation. Deconvoluting the thermogravimetric profiles revealed that asphaltene thermolysis in the air cannot be accurately described in terms of an nth order kinetic model because it involves some acceleratory phases. Also, thermogravimetric analyses of visbreaking streams revealed that char production in them is proportional to their asphaltene content. This relationship enables the thermogravimetric measurement of asphaltenes.

  18. Wetting Alteration of Solid Surfaces by Crude Oils and Their Asphaltenes Modification de la mouillabilité des surfaces solides par les pétroles bruts et leurs asphaltènes

    Directory of Open Access Journals (Sweden)

    Buckley J. S.

    2006-12-01

    Full Text Available Crude oils contain a variety of components - including asphaltenes - that can adsorb onto mineral surfaces and alter wetting. What distinguishes the asphaltenes from other constituents of an oil is their tendency to aggregate and even separate from the oil in response to changes in oil solvency. Because they change in size, asphaltenes can be viewed as both macromolecules and colloids. Their influence on wettability can change with this shift from molecular to colloidal regimes. As macromolecules, asphaltenes and other crude oil components with polar functionality can adsorb on mineral surfaces. Many different crude oils have been shown to have similar effects on wetting of dry silicate surfaces. When water is present, however, the results of exposing surfaces to different oils can be quite complex, depending on the distribution of water, the compositions of oil and brine, and mineralogy of rock surfaces. Acid and base numbers and the relationship between them provide a measure of the potential for a particular oil to alter wetting through ionic interactions. As colloids, asphaltenes can alter wetting by an additional mechanism. Near the onset of precipitation, wetting alteration occurs by surface precipitation because of the interfacial aggregation of the colloidal asphaltenes, which can precede flocculation in bulk. The influence of asphaltenes on wetting is thus strongly dependent on the environment in which they are found. Mixture refractive index is a useful measure for quantifying the stability of asphaltenes in a crude oil and thus in differentiating between macromolecular and colloidal contributions of asphaltenes to wetting alteration. Les pétroles bruts contiennent de nombreux constituants - dont les asphaltènes - qui peuvent être adsorbés sur les surfaces minérales et modifier leurs caractéristiques de mouillage. Ce qui distingue les asphaltènes des autres constituants de l'huile est leur tendance à s'agréger et même à se s

  19. Quantification of asphaltene precipitation by scaling equation

    Science.gov (United States)

    Janier, Josefina Barnachea; Jalil, Mohamad Afzal B. Abd.; Samin, Mohamad Izhar B. Mohd; Karim, Samsul Ariffin B. A.

    2015-02-01

    Asphaltene precipitation from crude oil is one of the issues for the oil industry. The deposition of asphaltene occurs during production, transportation and separating process. The injection of carbon dioxide (CO2) during enhance oil recovery (EOR) is believed to contribute much to the precipitation of asphaltene. Precipitation can be affected by the changes in temperature and pressure on the crude oil however, reduction in pressure contribute much to the instability of asphaltene as compared to temperature. This paper discussed the quantification of precipitated asphaltene in crude oil at different high pressures and at constant temperature. The derived scaling equation was based on the reservoir condition with variation in the amount of carbon dioxide (CO2) mixed with Dulang a light crude oil sample used in the experiment towards the stability of asphaltene. A FluidEval PVT cell with Solid Detection System (SDS) was the instrument used to gain experimental knowledge on the behavior of fluid at reservoir conditions. Two conditions were followed in the conduct of the experiment. Firstly, a 45cc light crude oil was mixed with 18cc (40%) of CO2 and secondly, the same amount of crude oil sample was mixed with 27cc (60%) of CO2. Results showed that for a 45cc crude oil sample combined with 18cc (40%) of CO2 gas indicated a saturation pressure of 1498.37psi and asphaltene onset point was 1620psi. Then for the same amount of crude oil combined with 27cc (60%) of CO2, the saturation pressure was 2046.502psi and asphaltene onset point was 2230psi. The derivation of the scaling equation considered reservoir temperature, pressure, bubble point pressure, mole percent of the precipitant the injected gas CO2, and the gas molecular weight. The scaled equation resulted to a third order polynomial that can be used to quantify the amount of asphaltene in crude oil.

  20. Properties of Tahe crude oil and influence of separation components on crude oil viscosity

    Energy Technology Data Exchange (ETDEWEB)

    Chaogang, Chen; Hongjun, Deng [Northwest Oilfield Branch Engineering and Technology Institute of Sinopec (China); Jixiang, Guo; Heyi, Wang; Meiqin, Lin [Enhanced Oil Recovery Research Center, China University of Petroleum (China)], email: guojx002@163.com

    2010-07-01

    The Tahe oil field in Xinjiang produces oil from depths of 5500m to 7000m whose temperatures range from 128 to 140 Celsius. The formation waters have a high salinity. To determine the major factors that contribute to the viscosity of the oil, such as saturate, aromatic resin, and asphaltene, a variety of techniques were used. Measurements were done using IR, scanning electron microscopy, energy spectrum analysis (EDX), elemental analysis, and ICP techniques. It was found, as predicted, that the viscosity of the crude oil decreased with increase of the temperature. However, different types of crude oil have various levels of temperature-sensitive turning points. The Tahe oil fields have a higher turning point due to the asphaltene and resins. To conduct the experiment the Tahe crude AD11 was separated into oil fractions using toluene as the solvent. It was concluded that the asphaltene has the greatest impact on viscosity.

  1. Aggregation of asphaltenes and development of inhibitors and dispersants in Brazilian crude oil; Agregacao de asfaltenos e desenvolvimento de inibidores e dispersantes em petroleos brasileiros

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, Rahoma Sadeg; Ramos, Antonio Carlos da Silva [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Quimica; Loh, Watson [Universidade Estadual de Campinas, SP (Brazil). Inst. de Quimica

    1999-07-01

    The behavior of two asphaltenes (C7I - insoluble in n-heptane and C5I - insoluble in n-pentane), obtained from samples of Brazilian crude oils, in aromatics solvents was investigated using from surface/interfacial tension data. The experiments were carried out at 25 o C using an automatic tensiometer and employing Du Nouy ring method. The results indicated the presence of a critical micelle concentration in the range of 4.0 e 16.0 g/L. Kinematic viscosity measurements has indicated still another aggregation at higher asphaltene concentration. The effects of some surfactants, and copolymers on the precipitation of asphaltenes, in crude oils, were investigated using optical microscopy for the determination of the onset of precipitation induced by the addition of n-heptane to the oil/inhibitor system. Positives results were found with low molecular weight nonylphenol ethoxylated (Renex) and ethoxylated alcohols. The dispersant effects of the same inhibitors were also investigated with the best results obtained using dodecylbenzenesulfonic acid. (author)

  2. Molecular thermodynamics for prevention of asphaltene precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jianzhong; Prausnitz, J.M.

    1996-06-01

    Crude petroleum is a complex mixture of compounds with different chemical structures and molecular weights. Asphaltenes, the heaviest and most polar fraction of crude oil, are insoluble in normal alkanes such as n-heptane, but they are soluble in aromatic solvents such as toluene. The molecular nature of asphaltenes and their role in production and processing of crude oils have been the topic of numerous studies. Under some conditions, asphaltenes precipitate from a petroleum fluid, causing severe problems in production and transportation Our research objective is to develop a theoretically based, but engineering-oriented, molecular-thermodynamic model which can describe the phase behavior of asphaltene precipitation in petroleum fluids, to provide guidance for petroleum-engineering design and production. In this progress report, particular attention is given to the potential of mean force between asphaltene molecules in a medium of asphaltene-free solvent. This potential of mean force is derived using the principles of colloid science. It depends on the properties of asphaltene and those of the solvent as well as on temperature and pressure. The effect of a solvent on interactions between asphaltenes is taken into account through its density and through its molecular dispersion properties.

  3. Asphaltenes analysis arising of non conventional oils; Analise de asfaltenos oriundos de petroleos nao convencionais

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Fernanda B. da; Fiorio, Paula G.P.; Guimaraes, Maria Jose O.C.; Seidl, Peter R. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Escola de Quimica

    2012-07-01

    The need to use heavy fractions in an efficient way in the production of nobler fractions has motivated the search for ways of separating the asphaltenes, since these molecules increase the viscosity of the fractions submitted to distillation, contribute to the formation of coke and to poisoning and deactivation of catalysts used in process such as cracking, reform, etc, besides provoking cloggings and blockages caused by its deposition, generating losses on the productivity and increases of the operational costs. This paper evaluates the influence of solvent blends (EQ-NP) in the selective extraction of constituents of three samples from Brazilian heavy crude. For the extraction process was used two solvent blends (N1P1 and N1P2). The solvent blend composed of N1P1 showed a higher selectivity in the extraction of aggregates than N1P2. The extracted fraction was characterized by Hydrogen Nuclear Magnetic Resonance ({sup 1}H-NMR) and revealed that the chemical species extracted from different blends exhibit very small differences. (author)

  4. Compositional thermodynamic model of asphaltenes flocculation out of crudes; Modelisation thermodynamique compositionnelle de la floculation des bruts asphalteniques

    Energy Technology Data Exchange (ETDEWEB)

    Szewczyk, V.

    1997-12-02

    The aim of this work is to propose to the oil industry a compositional thermodynamic model able to predict the operating conditions which induce asphaltenes flocculation out of crudes. In this study, various analytical methods (calorimetry, elemental analysis, {sup 13}C nuclear magnetic resonance, neutron diffusion,...) have been used in order to get a better description of the asphaltene fraction to infer its flocculation mechanism. The proposed model describes this flocculation as a thermodynamic transition inducing the formation of a new liquid phase with a high asphaltene content and formed by all the components initially in the crude: the asphaltene deposit. Asphaltenes are represented as a pseudo-component essentially made of carbon and hydrogen. The analytical modelling of the F11-F20 light fraction is the one proposed by Jaubert (1993). The F20+ heavy fraction is represented by four pseudo-components, their physical properties are calculated using the group contribution methods of Avaullee (1995) and of Rogalski and Neau (1990). The Peng-Robinson equation of state (1976) combined with the Abdoul and Peneloux group contribution mixing rules (1989) is used in order to restitute the gas-liquid-asphaltene deposit phase equilibria. This model not being able to compute flocculation conditions on a predictive manner, the method consists in fitting some physical properties of the pseudo-components introduced in the analytical representation of the asphaltene crudes. he obtained results show results show that the proposed flocculation model is then well adapted to the description of the thermodynamic properties (saturation pressures, relative volumes, flocculation curves) of asphaltene crudes within a relatively large range of temperature (30-150 deg C) and pressure (0.1-50 MPa), covering the majority of conditions met in oil production. (author) 109 refs.

  5. Evaluation of nano emulsion containing asphaltenes dispersant additive in dehydration of oil; Avaliacao de nanoemulsoes contendo aditivo dispersante de asfaltenos na desidratacao de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Priscila F. de; Rodrigues, Jessica S.; Mansur, Claudia R.E. [Universidade Federal do Rio de Janeiro/ Instituto de Macromoleculas/ Laboratorio de Macromoleculas e Coloides na Industria de Petroleo, Rio de Janeiro, RJ (Brazil)], e-mail: prisfrias@hotmail.com

    2011-07-01

    Due to the problem of the formation of emulsions type water-oil during oil production, new alternatives of the breakdown of these emulsions have been proposed over the years. Several polymers have been used to destabilize these emulsions and among them are those based on polyphenylene ether. The aim of this study was to develop nanoemulsions type oil / water, where an asphaltenes dispersant additive was dissolved in dispersed phase in order to evaluate them as a new alternative in the breakdown of oil emulsions. The nanoemulsions were prepared in the presence of surfactant based on polyoxide using a high pressure homogenizer (HPH). We obtained stable nanoemulsions for more than 30 days in the presence or absence of additive. These nanoemulsions were effective in water /oil phase separation, and the nanoemulsion containing the dispersant additive provided a faster separation of these phases. (author)

  6. Petroleum asphaltenes: Part 1. Asphaltenes, resins and the structure of petroleum; Les asphaltenes, composes petroliers. Partie 1: asphaltenes, resines et structure du petrole

    Energy Technology Data Exchange (ETDEWEB)

    Speight, J.G. [CD and W Inc., Laramine, Wyoming (United States)

    2004-07-01

    The definition of the nonvolatile constituents of petroleum (i.e., the asphaltene constituents, the resin constituents, and, to some extent, part of the oils fraction insofar as nonvolatile oils occur in residua and other heavy feedstocks) is an operational aid. It is difficult to base such separations on chemical or structural features. This is particularly true for the asphaltene constituents and the resin constituents, for which the separation procedure not only dictates the yield but can also dictate the quality of the fraction. For example, the use of different hydrocarbon liquids influences the yield by a considerable factor. The technique employed also dictates whether or not the asphaltene contains coprecipitated resins. This is based on the general definition that asphaltene constituents are insoluble in n -pentane (or in n-heptane) but resins are soluble n -pentane (or in n-heptane). The results of structural studies of asphaltene constituents are moving away from the older ideas that asphaltene constituents contained large polynuclear aromatic systems and there are a variety of functional types that also play a role in asphaltene behavior. The stability of petroleum is dependent upon the molecular relationships of the asphaltene and resin constituents and the balance with the other constituents of petroleum. Thus, the stability of petroleum can be represented by a three-phase system in which the asphaltene constituents, the aromatic fraction (including the resin constituents), and the saturate fraction are in a delicately balanced harmony. Various factors, such as oxidation, can have an adverse effect on the system, leading to instability or incompatibility as a result of changing the polarity, and bonding arrangements, of the species in crude oil. (author)

  7. Separation and characterization of asphaltenic subfractions

    Energy Technology Data Exchange (ETDEWEB)

    Honse, Siller O.; Ferreira, Silas R.; Mansur, Claudia R. E.; Lucas, Elizabete F. [Universidade Federal do Rio de Janeiro (IMA/UFRJ), RJ (Brazil). Inst. de Macromoleculas Professora Eloisa Mano; Gonzalez, Gaspar, E-mail: elucas@ima.ufrj.br [Centro de Pesquisas da PETROBRAS (CENPES), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    The structure of the various asphaltenic subfractions found in crude oil was evaluated. For this purpose, C5 asphaltenes were extracted from an asphaltic residue using n-pentane as the flocculant solvent. The different subfractions were isolated from the C5 asphaltenes by the difference in solubility in different solvents. These were characterized by infrared spectroscopy, nuclear magnetic resonance, X-ray fluorescence, elementary analysis and mass spectrometry. The results confirmed that the subfractions extracted with higher alkanes had greater aromaticity and molar mass. However, small solubility variations between the subfractions were attributed mainly to the variation in the concentrations of cyclical hydrocarbon compounds and metals (author)

  8. Separation of Asphaltenes by Polarity using Liquid-Liquid Extraction

    DEFF Research Database (Denmark)

    Andersen, Simon Ivar

    1997-01-01

    In order to investigate the nature of petroleum asphaltenes in terms of polarity a process was developed using initial liquid-liquid extraction of the oil phase followed by precipitation of the asphaltenes using n-heptane. The liquid-liquid extraction was performed using toluene-methanol mixtures...... with increasing content of toluene. Although large fractions of the crude oil (Alaska ´93) was extracted in the higher polarity solvents (high concentration of methanol), the asphaltene content of the dissolved material was low. As the toluene content increased more asphaltenes were transferred to the solvent...... of the maltene phase also increase while H/C decreases. The content of heteroatoms in the asphaltenes are relatively higher and apparently increase with the polarity of the solvent. It is concluded that these asphaltenes are indeed dominated by high molecular weight substances that cannot be extracted...

  9. The low temperature oxidation of Athabasca oil sand asphaltene observed from {sup 13}C, {sup 19}F, and pulsed field gradient spin-echo proton n.m.r. spectra

    Energy Technology Data Exchange (ETDEWEB)

    Desando, M.A.; Lahanjar, G.; Ripmeester, J.A.; Zupancic, I. [National Research Council of Canada, Ottawa, ON (Canada). Division of Chemistry

    1999-01-01

    Carbon-13 and fluorine-19 nuclear magnetic resonance spectra of chemically derivatized, by phase transfer methylation and trifluoroacetylation, Athabasca oil sand asphaltene, reveal a broad site distribution of different types of hydroxyl-containing functional groups, viz., carboxylic acids, phenols, and alcohols. The low temperature air oxidation of asphaltene, at ca. 130{degree}C for 3 days, generates a few additional carboxyl and phenolic groups. These results are consistent with a mechanism in which diaryl methylene and ether moieties react with oxygen. Self-diffusion coefficients, from the pulsed field gradient spin-echo proton magnetic resonance technique, suggest that low temperature oxidation does not appreciably alter the average particle size and diffusion properties of asphaltene in deuterochloroform. 55 refs., 9 figs., 3 tabs.

  10. Understanding mechanisms of asphaltene adsorption from organic solvent on mica.

    Science.gov (United States)

    Natarajan, Anand; Kuznicki, Natalie; Harbottle, David; Masliyah, Jacob; Zeng, Hongbo; Xu, Zhenghe

    2014-08-12

    The adsorption process of asphaltene onto molecularly smooth mica surfaces from toluene solutions of various concentrations (0.01-1 wt %) was studied using a surface forces apparatus (SFA). Adsorption of asphaltenes onto mica was found to be highly dependent on adsorption time and asphaltene concentration of the solution. The adsorption of asphaltenes led to an attractive bridging force between the mica surfaces in asphaltene solution. The adsorption process was identified as being controlled by the diffusion of asphaltenes from the bulk solution to the mica surface with a diffusion coefficient on the order of 10(-10) m(2)/s at room temperature, depending on the asphaltene bulk concentration. This diffusion coefficient corresponds to a hydrodynamic molecular radius of approximately 0.5 nm, indicating that asphaltene diffuses to mica surfaces as individual molecules at very low concentration (e.g., 0.01 wt %). Atomic force microscopy images of the adsorbed asphaltenes on mica support the results of the SFA force measurements. The results from the SFA force measurements provide valuable insights into the molecular interactions (e.g., steric repulsion and bridging attraction as a function of distance) of asphaltenes in organic media and hence their roles in crude oil and bitumen production.

  11. 轻质油油井沥青质沉淀清除作业%Cleanup operation of asphaltene precipitation in light oil wells

    Institute of Scientific and Technical Information of China (English)

    董涛; 王海涛; 高巧娟

    2015-01-01

    两伊边界轻质油油田主力产层A油组在生产过程中,沥青质在井筒析出、沉淀的现象很严重,是无水开采阶段影响油井生产时率的主要因素之一。A油组异常高压,地层原油中高含硫化氢,所以整个作业过程,油管和油套环空之间不允许建立循环,这些都给井筒沥青质沉淀清除工作带来了很大困难。本次施工先采用泵车小排量控压、分段挤入、分段浸泡以及分段返排的工艺,挤入过程中井筒被沥青沉淀堵死,之后改用连续油管通洗井和泵车小排量控压挤入与浸泡相结合的工艺,顺利完成作业,使油井恢复正常生产。本次作业历时5 d,现场施工过程艰难复杂,通过作业认识到高效的沥青质沉淀溶剂、连续油管通洗、泵车控压控排量挤入、浸泡时间和浸泡深度几方面紧密配合是保证施工成功的关键。%During production of the major productive zone-Oil Reservoir A in light oil oilifeld close to Iran and Iraq borders, asphaltene precipitation and settling in wellbore is a severe problems and is one of the factors which affect the production time efifciency of oil wells in water-free production period. The Oil Reservoir A has anomalously high pressure and formation crude oil contains large amount of hydrogen sulphide (H2S), so no circulation should be established between the tubing and casing annulus during the operation process. All these factors pose great dififculty for removing the asphaltene precipitation on wellbore. In this job, the pumping unit was ifrstly used to control the pressure with small displacement, squeeze in lfuid in stages and soak in stages and lfow back in stages. During squeezing, the wellbore was fully blocked by asphaltene precipitation.Then coiled tubing was used to drift and wash the well in conjunction with controlling the pressure by pumping unit with small displacement and soaking. The job was completed successfully and the

  12. Pyrolysis of petroleum asphaltenes from different geological origins and use of methylnaphthalenes and methylphenanthrenes as maturity indicators for asphaltenes

    Indian Academy of Sciences (India)

    Manoj Kumar Sarmah; Arun Borthakur; Aradhana Dutta

    2010-08-01

    Asphaltenes separated from two different crude oils from upper Assam, India, having different geological origins, viz. DK (Eocene) and JN (Oligocene–Miocene) were pyrolysed at 600°C and the products were analysed by gas chromatography–mass spectrometry (GC/MS) especially for the generated alkylnaphthalenes and alkylphenanthrenes. Both the asphaltenes produced aliphatic as well as aromatic compound classes. Alkylnaphthalenes and alkylphenanthrenes were identified by using reference chromatograms and literature data and the distributions were used to assess thermal maturity of the asphaltenes. The ratios of -substituted to α-substituted isomers of both alkylnaphthalenes and alkylphenanthrenes revealed higher maturity of the JN asphaltenes than the DK asphaltenes. For both the asphaltenes the abundance of 1-methylphenanthrene dominated over that of 9-methylphenanthrene showing the terrestrial nature of the organic matter.

  13. Pyrolysis of petroleum asphaltenes from different geological origins and use of methylnaphthalenes and methylphenanthrenes as maturity indicators for asphaltenes

    Indian Academy of Sciences (India)

    Manoj Kumar Sarmah; Arun Borthakur; Aradhana Dutta

    2013-04-01

    Asphaltenes separated from two different crude oils from upper Assam, India, having different geological origins, viz. DK(eocene) and JN (oligocene–miocene) were pyrolysed at 600 °C and the products were analysed by gas chromatography–mass spectrometry (GC/MS) especially for the generated alkylnaphthalenes and alkylphenanthrenes. Both the asphaltenes produce aliphatic as well as aromatic compound classes. Alkylnaphthalenes and alkylphenanthrenes were identified by using reference chromatograms and literature data and the distributions used to assess thermalmaturity of the asphaltenes. The ratios of -substituted to -substituted isomers of both alkylnaphthalenes and alkylphenanthrenes revealed higher maturity of the JN asphaltenes than the DK asphaltenes. For both the asphaltenes, the abundance of 1-methylphenanthrene dominates over that of 9-methylphenanthrene showing the terrestrial nature of the organic matter.

  14. Comparing ignitability for in situ burning of oil spills for an asphaltenic, a waxy and a light crude oil as a function of weathering conditions under arctic conditions

    DEFF Research Database (Denmark)

    Fritt-Rasmussen, Janne; Brandvik, Per Johan; Villumsen, Arne

    2012-01-01

    In situ burning of oil spills in the Arctic is a promising countermeasure. In spite of the research already conducted more knowledge is needed especially regarding burning of weathered oils. This paper uses a new laboratory burning cell (100 mL sample) to test three Norwegian crude oils, Grane...... (asphalthenic), Kobbe (light oil) and Norne (waxy), for ignitability as a function of ice conditions and weathering degree. The crude oils (9 L) were weathered in a laboratory basin (4.8 m3) under simulated arctic conditions (0, 50 and 90% ice cover). The laboratory burning tests show that the ignitability...... is dependent on oil composition, ice conditions and weathering degree. In open water, oil spills rapidly become “not ignitable” due to the weathering e.g. high water content and low content of residual volatile components. The slower weathering of oil spills in ice (50 and 90% ice cover) results in longer time...

  15. A gallery of oil components, their metals and Re-Os signatures

    Science.gov (United States)

    Stein, Holly J.; Hannah, Judith L.

    2016-04-01

    Most sediment-hosted metallic ore deposits are one degree of freedom from hydrocarbon. That is, sulfide fluid inclusions may contain vestiges of travel in tandem with hydrocarbon-bearing fluids. For metallic ore deposits of stated metamorphic and magmatic origin, the degrees of freedom are several times more or, in some cases, no relationship exists. Still, the fetish for stereotyping and classifying ore types into hardline ore deposit models (or hybrid models when the data are wildly uncooperative) impedes our ability to move toward a better understanding of source rock. Fluids in the deeper earth, fluids in the crust, and the extraterrestrial rain of metals provide the Re-Os template for oil. So, too, this combination ultimately drives the composition of many metallic ore deposits. The world of crude oil and its complex history of maturation, migration, mixing, metal-rich asphaltene precipitation, and subsequent mobility of lighter and metal-poor components, is an untapped resource for students of ore geology. In the same way that Mississippi Valley-type lead and zinc deposits are described as the outcome of two converging and mixing fluids (metal-bearing and sulfur-bearing fluids), asphaltene precipitation can be an outcome of a lighter oil meeting and mixing with a heavier one. In the petroleum industry, this can spell economic disaster if the pore-space becomes clogged with a non-producible heavy oil or solid bitumen. In ore geology, sulfide precipitation on loss of permeability may create a Pb-Zn deposit. Petroleum systems provide a gallery of successive time-integrated Re-Os results. Heavy or biodegraded oils, if intersected by lighter oil or gas, can generate asphaltite or tar mats, and release a reservoir of still lighter oil (or gas). During this process there are opportunities for separation of metal-enriched aqueous fluids that may retain an imprint of their earlier hydrocarbon history, ultimately trapped in fluid inclusions. Salinity, temperature and p

  16. Properties of the Langmuir films made by petroleum asphaltenes. Model systems of crude oil-water emulsions; Proprietes des films de Langmuir formes par des asphaltenes du petrole. Systemes modeles des emulsions eau - petrole brut

    Energy Technology Data Exchange (ETDEWEB)

    Deghais, S.; Solimando, R. [Institut National Polytechnique de Lorraine, Ecole Nationale Superieure des Industries Chimiques, Lab. de Thermodynamique des Separations, 54 - Nancy (France); Zywocinski, A.; Rogalska, E. [Universite Henri Poincare, Lab. de Physco-Chimie des Colloides, UMR CNRS 7565, 54 - Vandoeuvre les Nancy (France); Rogalski, M.; Rogalska, E. [Metz Univ., Lab. de Thermodynamique et d' Analyse Chimique, 57 (France)

    2001-07-01

    This work deals with the analysis of the properties of the water-petroleum fluid interfaces using the Langmuir films technique. The stability of the water-petroleum emulsions is ensured by complex interactions which exist at the interface between paraffins and heavy petroleum compounds like asphaltenes and resins. The experiments performed have shown that the stabilizing properties of the asphaltene films depend on the dielectric constant of the fluid, on the presence or not of resins, and on the presence of possible paraffinic depositions. (J.S.)

  17. The relationship between SARA fractions and crude oil stability

    Directory of Open Access Journals (Sweden)

    Siavash Ashoori

    2017-03-01

    Full Text Available Asphaltene precipitation and deposition are drastic issues in the petroleum industry. Monitoring the asphaltene stability in crude oil is still a serious problem and has been subject of many studies. To investigate crude oil stability by saturate, aromatic, resin and asphaltene (SARA analysis seven types of crudes with different components were used. The applied methods for SARA quantification are IP-143 and ASTM D893-69 and the colloidal instability index (CII is computed from the SARA values as well. In comparison between CII results, the values of oil compositions demonstrated that the stability of asphaltenes in crude oils is a phenomenon that is related to all these components and it cannot be associated only with one of them, individually.

  18. Investigation of Asphaltene Precipitation at Elevated Temperature

    DEFF Research Database (Denmark)

    Andersen, Simon Ivar; Lindeloff, Niels; Stenby, Erling Halfdan

    1998-01-01

    In order to obtain quantitative data on the asphaltene precipitation induced by the addition of n-alkane (heptane) at temperatures above the normal boiling point of the precipitant, a high temperature/high pressure filtration apparatus has been constructed. Oil and alkane are mixed at the appropr...

  19. Study on the polarity, solubility, and stacking characteristics of asphaltenes

    KAUST Repository

    Zhang, Long-li

    2014-07-01

    The structure and transformation of fused aromatic ring system in asphaltenes play an important role in the character of asphaltenes, and in step affect the properties of heavy oils. Polarity, solubility and structural characteristics of asphaltenes derived from Tahe atmospheric residue (THAR) and Tuo-826 heavy crude oil (Tuo-826) were analyzed for study of their internal relationship. A fractionation method was used to separate the asphaltenes into four sub-fractions, based on their solubility in the mixed solvent, for the study of different structural and physical-chemical properties, such as polarity, solubility, morphology, stacking characteristics, and mean structural parameters. Transmission electron microscope (TEM) observation can present the intuitive morphology of asphaltene molecules, and shows that the structure of asphaltenes is in local order as well as long range disorder. The analysis results showed that n-heptane asphaltenes of THAR and Tuo-826 had larger dipole moment values, larger fused aromatic ring systems, larger mean number of stacking layers, and less interlayer spacing between stacking layers than the corresponding n-pentane asphaltenes. The sub-fractions that were inclined to precipitate from the mixture of n-heptane and tetrahydrofuran had larger polarity and less solubility. From the first sub-fraction to the fourth sub-fraction, polarity, mean stacking numbers, and average layer size from the TEM images follow a gradual decrease. The structural parameters derived from TEM images could reflect the largest fused aromatic ring system in asphaltene molecule, yet the parameters derived from 1H NMR data reflected the mean message of poly-aromatic ring systems. The structural parameters derived from TEM images were more consistent with the polarity variation of sub-fractions than those derived from 1H NMR data, which indicates that the largest fused aromatic ring system will play a more important role in the stacking characteristics of

  20. Characterisation of the non-asphaltene products of mild chemical degradation of asphaltenes

    Energy Technology Data Exchange (ETDEWEB)

    Ekweozor, C.M.

    1986-01-01

    The major steranes of the non-asphaltene fraction of Nigerian tar sand bitumen (maltene) are the C{sub 27-29} and C{sub 28-29} regular steranes. The reducing-metal reaction products of the corresponding asphaltenes (maltene-I) contain mainly C{sub 27-29} regular steranes with the 14{beta}(H),17{beta}(H);20R+S and 14{alpha}(H),17{alpha}(H);20R+S configurations as well as the corresponding diasteranes having the 13{beta}(H),17{alpha}(H);20R+S configuration. These sterane distributions suggest that maltene-I corresponds to an unaltered oil while the maltene is equivalent to the product of severe biodegradation of maltene-I. This is consistent with maltene-I being the remnant of original oil trapped within the asphaltene matrix and protected from the effect of in-reservoir biodegradation. Degradation of Nigerian asphaltenes by refluxing with ferric chloride-acetic anhydride or methanolic potassium hydroxide also releases soluble reaction products having the characteristics of unaltered oil such as the presence of n-alkanes having an unbiased distribution. These methods appear to be milder and more suitable than reducing-metal reactions for releasing hydrocarbons occluded by asphaltenes. 15 refs., 3 figs., 2 tabs.

  1. Characterization of the non-asphaltene products of mild chemical degradation of asphaltenes

    Energy Technology Data Exchange (ETDEWEB)

    Ekweozor, C.M.

    1986-01-01

    The major steranes of the non-asphaltene fraction of Nigerian tar sand bitumen (maltene) are the C/sub 27/-C/sub 29/ diasteranes (13..beta.. (H),17..cap alpha.. (H); 20 R + S) and C/sub 28/-C/sub 29/ regular steranes (14..beta.. (H),17..beta.. (H); 20S). The reducing metal reaction products of the corresponding asphaltenes (maltene-I) contain mainly C/sub 27/-C/sub 29/ regular steranes with the 14..beta.. (H),17..beta.. (H); 20R + S and 14..cap alpha.. (H),17..cap alpha.. (H); 20R + S configurations as well as the corresponding diasteranes having the 13..beta.. (H),17..cap alpha.. (H); 20R + S configuration. These sterane distributions suggest that maltene-I corresponds to an unaltered oil whilst the maltene is equivalent to the product of severe biodegradation of maltene-I. This is consistent with maltene-I being the remnant of original oil trapped within the asphaltene matrix and protected from the effect of in-reservoir biodegradation. Degradation of Nigerian asphaltenes by refluxing with ferric chloride-acetic anhydride or methanolic potassium hydroxide also releases soluble reaction products having the characteristics of unaltered oil such as the presence of n-alkanes having an unbiased distribution. These methods appear to be milder and more suitable than reducing metal reactions for releasing hydrocarbons occluded by asphaltenes.

  2. The effect of asphaltene particle size and distribution on the temporal advancement of the asphaltene deposition profile in the well column

    Science.gov (United States)

    Zeinali Hasanvand, Mahdi; Mosayebi Behbahani, Reza; Feyzi, Farzaneh; Ali Mousavi Dehghani, Seyed

    2016-05-01

    Asphaltene deposition in oil wells is an inconvenient production problem. Generating a precise deposition model for the well column is essential for optimal well design and prevention/reduction of deposition-associated difficulties. The goal of this study is to determine the effects of various parameters on the deposition process. These parameters include oil viscosity, temperature, flow velocity, well diameter and asphaltene particle size and particle size distribution. The first five parameters are analyzed using Escobedo and Mansoori (2010), Cleaver and Yates (1975) and Friedlander and Johnstone (1957) asphaltene deposition models. The last parameter (asphaltene particle size distribution) is not directly included in the asphaltene deposition models. Therefore, a dynamic well column model is generated by combining transport phenomena (mass, heat and momentum transfer) equations with thermodynamic models. The model is fine-tuned and verified based on field data from an Iranian producing oil well with frequent asphaltene deposition problem and subsequently used for predicting the time-dependent development of the asphaltene deposition profile in the well column for a series of asphaltene particle size distributions. The results show the effect of the said parameters depends on how the buffer layer and Brownian motion are defined. The Escobedo and Mansoori (2010) model is found to make better predictions of deposited asphaltene in the studied well.

  3. Petroleum asphaltenes Part 2. The effect of asphaltenes and resin constituents on recovery and refining processes; Les asphaltenes, composes petroliers - partie 2: l'effet des asphaltenes et des resines sur les procedes de recuperation et de raffinage

    Energy Technology Data Exchange (ETDEWEB)

    Speight, J.G. [CD and W Inc., Laramine, Wyoming (United States)

    2004-07-01

    Petroleum is a complex but delicately balanced system that depends upon the relationship of the constituent fractions to each other and the relationships are dictated by molecular interactions. Thus, some aspects of recovery and refining chemistry, especially the chemistry of the deposition of asphaltenic material (degradation or reaction products of the asphaltene constituents and the resin constituents), can be proposed by virtue of the studies that have led further knowledge of the nature of asphaltene constituents and the resin constituents and particularly the nature of their interaction in crude oil. (author)

  4. Nature of hydrogen bonding in coal-derived asphaltenes

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, S.R.; Li, N.C.

    1978-02-01

    Reports are presented on near-infrared and proton magneti resonance studies of hydrogen bonding between the hydroxyl group of o-phenylphenol (OPP) and two coal derived asphaltenes, and their acid and base components. The asphaltenes were prepared from bituminous coal under the same conditions except that one was prepared using a CoMo catalyst. The results of the studies show that the use of the CoMo catalyst leads to a base asphaltene component of lower molecular weight and higher hydrogen-bond acceptor strength.

  5. Microarray analysis of Neosartorya fischeri using different carbon sources, petroleum asphaltenes and glucose-peptone

    OpenAIRE

    Edna L. Hernández-López; Ramírez-Puebla, Shamayim T.; Rafael Vazquez-Duhalt

    2015-01-01

    Asphaltenes are considered as the most recalcitrant petroleum fraction and represent a big problem for the recovery, separation and processing of heavy oils and bitumens. Neosartorya fischeri is a saprophytic fungus that is able to grow using asphaltenes as the sole carbon source [1]. We performed transcription profiling using a custom designed microarray with the complete genome from N. fischeri NRRL 181 in order to identify genes related to the transformation of asphaltenes [1]. Data ana...

  6. COMPARISON BETWEEN ASPHALTENES (SUBFRACTIONS EXTRACTED FROM TWO DIFFERENT ASPHALTIC RESIDUES: CHEMICAL CHARACTERIZATION AND PHASE BEHAVIOR

    Directory of Open Access Journals (Sweden)

    Silas R. Ferreira

    2016-01-01

    Full Text Available Asphaltenes are blamed for various problems in the petroleum industry, especially formation of solid deposits and stabilization of water-in-oil emulsions. Many studies have been conducted to characterize chemical structures of asphaltenes and assess their phase behavior in crude oil or in model-systems of asphaltenes extracted from oil or asphaltic residues from refineries. However, due to the diversity and complexity of these structures, there is still much to be investigated. In this study, asphaltene (subfractions were extracted from an asphaltic residue (AR02, characterized by NMR, elemental analysis, X-ray fluorescence and MS-TOF, and compared to asphaltene subfractions obtained from another asphaltic residue (AR01 described in a previous article. The (subfractions obtained from the two residues were used to prepare model-systems containing 1 wt% of asphaltenes in toluene and their phase behavior was evaluated by measuring asphaltene precipitation onset using optical microscopy. The results obtained indicated minor differences between the asphaltene fractions obtained from the asphaltic residues of distinct origins, with respect to aromaticity, elemental composition (CHN, presence and content of heteroelements and average molar mass. Regarding stability, minor differences in molecule polarity appear to promote major differences in the phase behavior of each of the asphaltene fractions isolated.

  7. Relations between interfacial properties and heavy crude oil emulsions stability; Relations entre les proprietes interfaciales et la stabilite des emulsions de brut lourd

    Energy Technology Data Exchange (ETDEWEB)

    Hoebler-Poteau, S.

    2006-02-15

    Oil in water emulsions are currently being investigated to facilitate the transport of viscous heavy oils. The behavior of these emulsions is largely controlled by oil / water interfaces. The surface-active components of crude oil such as asphaltenes and naphthenic acids compete among themselves at these interfaces and also with possibly added synthetic surfactant emulsifier.Here, we present a study of dynamic interfacial tension and rheology of interfaces between water and a model oil (toluene) in which asphaltenes and other surface active molecules from crude oil are dissolved. We show that different parameters such as aging of the interface, asphaltenes concentration, the pH and salinity of the aqueous phase have a strong influence on interfacial properties of asphaltenes at the oil/water interface. Several micro-pipette experiments, in which micrometric drops have been manipulated, are described as well as small angle neutron scattering measurements. The influence of lower molecular weight surface-active species, such as the natural naphthenic acids contained in maltenes (crude oil without asphaltenes) has been investigated, and an interaction between asphaltenes and maltenes which facilitates molecular arrangement at the interface was detected. The microscopic properties of the different interfaces and the stability of the corresponding emulsions are determined to be correlated.The results obtained on model emulsions and model oil/water interfaces were found to be helpful in order to explain and predict the behavior of heavy crude oil emulsions. (author)

  8. The influence of asphaltenes of the petroleum on the rheology of O/W (Oil/Water) emulsions; Influencia de asfaltenos do petroleo sobre a reologia de emulsoes O/A (Oleo/Agua)

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Ronaldo Goncalves dos; Mohamed, Rahoma Sadeg; Loh, Watson; Bannwart, Antonio Carlos [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil)

    2004-07-01

    Heavy oils represent a large fraction of the Brazilian petroleum reserves and display a great potential for application as substitute to the conventional oils, provided a suitable technology for their transportation is available. The high viscosity of these heavy oils leads to high flow resistance and increase in the recovery and transportation costs. Methodologies employed to reduce these problems involve application of heat of addition of diluents or lighter oils, but are associated with high costs. Formation of low viscosity oil-in-water emulsions has been proposed as an alternative for the transportation of heavy oils, as investigated in this work. Preliminary results indicate significant viscosity decreases upon emulsification of heavy oils (viscosities greater than 1,000 cP) forming o/w emulsions with high oil content (between 50-65 vol. %), which display viscosities within 4-25 cP. Additionally, the effect of different surfactants, methodology of preparation and oil asphaltene content on the emulsion stability was also evaluated. These results confirm the potential of emulsification as a viable methodology for heavy oil transportation. (author)

  9. Effect of asphaltene structure on association and aggregation using molecular dynamics.

    Science.gov (United States)

    Sedghi, Mohammad; Goual, Lamia; Welch, William; Kubelka, Jan

    2013-05-01

    The aggregation of asphaltenes has been established for decades by numerous experimental techniques; however, very few studies have been performed on the association free energy and asphaltene aggregation in solvents. The lack of reliable and coherent data on the free energy of association and aggregation size of asphaltene has imposed severe limitations on the thermodynamic modeling of asphaltene phase behavior. Current thermodynamic models either consider asphaltenes as non-associating components or use fitting parameters to characterize the association. In this work, the relations between Gibbs free energy of asphaltene association and asphaltene molecular structure are studied using molecular dynamics (MD). The free energy of association is computed from the potential of mean force profile along the separation distance between the centers of mass of two asphaltene molecules using the umbrella sampling technique in the GROMACS simulation package. The average aggregation number for asphaltene nanoaggregates and clusters is also calculated through MD simulations of 36 asphaltene molecules in toluene and heptane in order to estimate the effects of association free energy and steric repulsion on the aggregation behavior of asphaltenes. Our simulation results confirm that the interactions between aromatic cores of asphaltene molecules are the major driving force for association as the energy of association increases substantially with the number of aromatic rings. Moreover, heteroatoms attached to the aromatic cores have much more influence on the association free energy than to ones attached to the aliphatic chains. The length and number of aliphatic chains do not seem to have a noticeable effect on asphaltene dimerization; however, they have a profound effect on asphaltene aggregation size since steric repulsion can prevent asphaltenes from forming T-shape configurations and therefore decrease the aggregation size of asphaltenes significantly. Our MD simulation

  10. Adsorption and wettability study of methyl ester sulphonate on precipitated asphaltene

    Science.gov (United States)

    Okafor, H. E.; Sukirman, Y.; Gholami, R.

    2016-03-01

    Asphaltene precipitation from crude oil and its subsequent aggregation forms solid, which preferentially deposit on rock surfaces causing formation damage and wettability changes leading to loss of crude oil production. To resolve this problem, asphaltene inhibitor has been injected into the formation to prevent the precipitation of asphaltene. Asphaltene inhibitors that are usually employed are generally toxic and non-biodegradable. This paper presents a new environmentally friendly asphaltene inhibitor (methyl ester sulphonate), an anionic surfactant, which has excellent sorption on formation rock surfaces. Result from adsorption study validated by Langmuir and Freundlich models indicate a favourable adsorption. At low volumes injected, methyl ester sulphonate is capable of reverting oil-wet sandstone surface to water-wet surface. Biodegradability test profile shows that for concentrations of 100-5000ppm it is biodegradable by 65-80%.

  11. 沥青质引发的蜡油体系结蜡层分层现象及分层规律%Stratification phenomenon and laws of wax deposits of waxy oil triggered by asphaltene addition

    Institute of Scientific and Technical Information of China (English)

    李传宪; 蔡金洋; 程梁; 杨飞; 张皓若; 张莹

    2016-01-01

    Stratification phenomenon and laws of wax deposits were studied for oil samples 1 (without asphaltene) and 2 (0.75%(mass) asphaltene) with the same wax content using the Couette wax deposition device. In the study of stratification phenomenon of wax deposits, the macroscopic morphology, DSC curves, amount of precipitated wax and wax crystal microcosmic morphology of the outer and inner deposits of oil samples 1 and 2 were analyzed. It was found that the deposit of oil sample 1 had no obvious stratification while that of oil sample 2 had obvious stratification, proving that the asphaltene led to the stratification of wax deposit. Compared with outer deposit, the WAT, amount of precipitated wax and asphaltene content of inner deposit of oil sample 2 increased significantly. It was found in the study of stratification laws of wax deposits that the outer wax deposition mass decreased with the increase of the temperature of wax deposition barrel, the temperature difference of oil and wax deposition barrel and the rotate speed of oil sample barrel, while the inner one deceased with the increase of the temperature of wax deposition barrel and increased with the temperature difference of oil and wax deposition barrel and the rotate speed of oil sample barrel. The total wax deposition mass deceased with the increase of the temperature of wax deposition barrel and the rotate speed of oil sample barrel, and increased firstly then decreased with the increase of the temperature difference of oil and wax deposition barrel.%利用自主研发的Couette结蜡装置,对蜡含量相同的油样1(不含沥青质)和油样2[含0.75%(质量分数)沥青质]进行结蜡实验,并研究其结蜡层的分层现象和分层规律。通过对油样1和油样2结蜡表层和底层的宏观形貌、DSC放热、析蜡量、蜡晶微观形貌的分析发现:油样1结蜡层无明显分层现象,而油样2结蜡层分层现象明显,沥青质的加入导致了结蜡层的分

  12. Combustion of drops of Mexican fuel oils with high asphaltenes content; Combustion de gotas de combustoleos mexicanos con alto contenido de asfaltenos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Rodriguez, Jose Francisco [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-09-01

    In this work the combustion of fuel drops with a content of 18% of asphaltenes has been studied . The results obtained for this fuel were compared with the ones obtained for another with a content of 12% asphaltenes. The drops were suspended in a platinum filament and burned in an spherical radiant furnace. The drop size varied between 600 and 800 microns. The fuel drops with 12% asphaltenes showed shorter combustion times, a smaller diameter increment of the smaller diameter during the combustion stages and also a shorter burning time of the carbonaceous residue than the fuel drops with a content of 18% asphaltenes. [Espanol] En el presente trabajo se ha estudiado la combustion de gotas de combustible con 18% de contenido de asfaltenos. Los resultados obtenidos para este combustible se compararon con los obtenidos para otro con 12% de contenido de asfaltenos. Las gotas fueron suspendidas en un filamento de platino y quemadas en un horno radiante esferico. El tamano de las gotas vario entre 600 y 800 micras. Las gotas de combustible con 12% de asfaltenos mostraron tiempos de combustion mas cortos, un incremento del diametro menor durante las etapas de combustion y un tiempo de quemado del residuo carbonoso tambien mas corto que las gotas del combustible con 18% de contenido de asfaltenos.

  13. Prediction of Gas Injection Effect on Asphaltene Precipitation Onset Using the Cubic and Cubic-Plus-Association Equations of State

    DEFF Research Database (Denmark)

    Arya, Alay; Liang, Xiaodong; von Solms, Nicolas

    2017-01-01

    Gas injection is a proven enhanced oil recovery technique. The gas injection changes the reservoir oil composition, temperature, and pressure conditions, which may result in asphaltene precipitation. In this work, we have used a modeling approach from the literature in order to predict asphaltene...

  14. Chemical modification of cobalt ferrite nanoparticles with possible application as asphaltene flocculant agent

    Directory of Open Access Journals (Sweden)

    G. E. Oliveira

    2013-06-01

    Full Text Available Asphaltenes can cause enormous losses in the oil industry, because they are soluble only in aromatic solvents. Therefore, they must be removed from the petroleum before it is refined, using flocculant agents. Aiming to find new materials that can work as flocculant agents to asphaltenes, cobalt ferrite nanoparticles were chemically modified through acid-base reactions using dodecylbenzene sulfonic acid (DBSA to increase their lipophilicity. Nanoparticle synthesis was performed using the co-precipitation method followed by annealing of these nanoparticles, aiming to change the structural phase. Modified and unmodified nanoparticles were tested by FTIR-ATR, XRD and TGA/DTA. In addition, precipitation onset of the asphaltenes was performed using modified and unmodified nanoparticles. These tests showed that modified nanoparticles have a potential application as flocculant agents used to remove asphaltenes before oil refining, since the presence of nanoparticles promotes the asphaltene precipitation onset with the addition of a small amount of non-solvent.

  15. Chemical modification of cobalt ferrite nanoparticles with possible application as asphaltene flocculant agent

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, G.E.; Clarindo, J.E.S.; Santo, K.S.E., E-mail: geiza.oliveira@ufes.br [Universidade Federal do Espirito Santo (CCE/DQUI/UFES), Vitoria, ES (Brazil). Centro de Ciencias Exatas. Dept. de Quimica; Souza Junior, F.G. [Universidade Federal do Rio de Janeiro (IMA/UFRJ), Rio de Janeiro, RJ (Brazil). Instituto de Macromoleculas

    2013-11-01

    Asphaltenes can cause enormous losses in the oil industry, because they are soluble only in aromatic solvents. Therefore, they must be removed from the petroleum before it is refined, using flocculant agents. Aiming to find new materials that can work as flocculant agents to asphaltenes, cobalt ferrite nanoparticles were chemically modified through acid-base reactions using dodecylbenzene sulfonic acid (DBSA) to increase their lipophilicity. Nanoparticle synthesis was performed using the co-precipitation method followed by annealing of these nanoparticles, aiming to change the structural phase. Modified and unmodified nanoparticles were tested by FTIR-ATR, XRD and TGA/DTA. In addition, precipitation onset of the asphaltenes was performed using modified and unmodified nanoparticles. These tests showed that modified nanoparticles have a potential application as flocculant agents used to remove asphaltenes before oil refining, since the presence of nanoparticles promotes the asphaltene precipitation onset with the addition of a small amount of non-solvent (author)

  16. Synthesis and evaluation of copolymer based on cardanol and styrene on the stability of asphaltenes; Sintese e avaliacao de copolimero a base de cardanol e estireno sobre a estabilidade dos asfaltenos

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, Tatiana S.; Spinelli, Luciana S., E-mail: tatianaloureiro@ima.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Instituto de Macromoleculas

    2015-07-01

    The destabilization of asphaltenes in crude oil mainly happens due to variations in pressure, temperature and oil composition, causing significant losses. Polymers containing specific groups can be used as asphaltenes stabilizers and thus, avoid your precipitation, or as asphaltenes flocculants to assist the removal of suspended particles in a particular oil. The monitoring of asphaltenes precipitation is usually evaluated by tests with variation in stability of asphaltenes in function of adding a flocculant solvent. In this work, it was evaluated the influence of a synthesized copolymer based on cardanol and styrene on the stability of asphaltenes. The stability of asphaltenes was monitored by precipitation tests induced by a flocculant agent (n-heptane), using an ultraviolet-visible (UV-Vis) spectrometer. The structural characterization of copolymer was performed by FTIR and {sup 1}H NMR. The results showed that copolymer can act as asphaltene flocculant. (author)

  17. 稠油沥青质的基本化学组成结构与缔合性研究%STUDY ON CASIC CHE MICAL STRUCTURE AND ASSOCIATION OF ASPHALTENE IN HEAVY OIL

    Institute of Scientific and Technical Information of China (English)

    张庆; 邓文安; 李传; 吴乐乐

    2014-01-01

    从4种不同稠油中分离沉淀出正戊烷沥青质,用红外光谱表征了其官能团结构,用1 H-N MR 结合相对分子质量及元素分析测定了沥青质的基本结构参数,并得出了沥青质的平均分子式,同时测定了沥青质的偶极矩来表征其极性。研究结果表明:稠油沥青质分子中杂原子的存在使其含有较多的极性基团,沥青质具有较大极性。杂原子含量越高,其极性越大,缔合性越强,缔合数越高。此外,用两种方法计算了沥青质的分子直径,结果表明:相对分子质量越大时,沥青质分子尺寸越大,但特性黏度法测得的分子直径与其选用的溶剂有关,且关联出的分子直径偏大,而相对密度和相对分子质量法能较好地反映分子颗粒尺寸。%Four kinds of asphaltenes were obtained from four different heavy oils with n-pentane as solvent.Their functional structures were characterized by FTIR spectroscopy,and the basic structural parameters of the asphaltenes were determined by 1 H-NMR,then the average molecular formula of the asphaltene were given by molecular weight and element content.The dipole moments were also meas-ured to indicate the polarities of the asphaltene molecules.The results show that the presence of het-eroatom in asphaltene makes the asphalt form the polar groups with high polarity,and the higher the content of impurity atoms,the greater the polarity,the stronger the association,the higher the associa-tion numbers.In addition,molecular diameters were measured by two methods:intrinsic viscosity method,and relative density and relative molecular mass method.With the increase of relative molecu-lar mass,the molecular size of asphaltene becomes larger.However,the molecular diameter measured by viscosity method is related to the selected solvents and usually is larger than the size obtained by rela-tive density and relative molecular mass method,and the latter method can well reflect

  18. An electron spin resonance probe method for the understanding of petroleum asphaltene macrostructure

    Energy Technology Data Exchange (ETDEWEB)

    Wong, G.K.; Yen, T.F. [Department of Civil and Environmental Engineering, University of Southern California, 3620 South Vermont Avenue 224A, 90089-2531 Los Angeles, CA (United States)

    2000-10-01

    Molecularly, petroleum asphaltenes are induced dipoles, which agglomerate into nanometer-sized colloids of different aggregation states. The electron spin resonance (ESR) vanadyl probe method is used to investigate the asphaltene macrostructures under different temperatures and microwave powers. Oxovanadium complexes native to an asphaltene isolated from Boscan crude oil, Venezuela, function as tracers to examine the behavior of micelle agglomerates when subjected to a microwave field. Both mobile and bounded oxovanadium compounds in colloidal asphaltene solution are in a state of equilibrium. It is noted that a greater amount of mobile vanadyl complexes can be stabilized in a dispersing medium (single-aromatic ring solvent series) with a higher-valued Hansen hydrogen bonding solubility parameter. We found that conversion of ESR vanadyl hyperfine lines occurs from anisotropic to isotropic as the temperature of a 4% Boscan asphaltene solution in o-xylene increased from 25C to 100C. Free tumbling of total vanadyl complexes in organic solvent signifies dissociation of micelles at packing imperfections prior to their release from aromatic hosts. Coupling of petroleum asphaltenes with microwave power can overcome charge transfer and charge balance interactions within micelle agglomerates. The relative content of mobile to bounded vanadyl complexes in 4% Boscan asphaltene solution of o-xylene was found to increase with microwave power at 45C. Microwave energy will enable effective dispersion of colloidal asphaltene in heavy oil refining and upgrading.

  19. Change of asphaltene and resin properties after catalytic aquathermolysis

    Institute of Scientific and Technical Information of China (English)

    Yi Yufeng; Li Shuyuan; Ding Fuchen; Yu Hang

    2009-01-01

    Resin and asphaltene were separated from Liaohe heavy oil.Catalytic aquathermolysis of asphaltene and resin was investigated by using water soluble catalysts (NiSO4 and FeSO4) and oil soluble catalysts (nickel naphthenate and iron naphthenate).Before and after aquathermolysis, the properties of the resin and asphaltene was compared by means of ultimate analysis, vapor pressure osmometer (VPO) average molecular weight, X-ray diffraction (XRD), 13C and 1H nuclear magnetic resonance (NMR).The conversion sequence was as follows: No-catalystasphaltene and resin increased after reaction without catalyst.But the catalysts restrained this trend.The H/C ratio of asphaitene and resin decreased after reaction.From the results of average structural parameters and molecular weight, it was found that asphaltene and resin were partly aggregated after aquathermolysis.

  20. An experimental study of asphaltene particle sizes in n-heptane-toluene mixtures by light scattering

    Energy Technology Data Exchange (ETDEWEB)

    Rajagopal, K.; Silva, S.M.C. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Escola de Engenharia. Dept. de Engenharia Quimica]. E-mail: raja@eq.ufrj.br

    2004-12-01

    The particle size of asphaltene flocculates has been the subject of many recent studies because of its importance in the control of deposition in petroleum production and processing. We measured the size of asphaltene flocculates in toluene and toluene - n-heptane mixtures, using the light-scattering technique. The asphaltenes had been extracted from Brazilian oil from the Campos Basin, according to British Standards Method IP-143/82. The asphaltene concentration in solution ranged between 10{sup -6} g/ml and 10{sup -7} g/ml. Sizes was measured for a period of about 10000 minutes at a constant temperature of 20 deg C. We found that the average size of the particles remained constant with time and increase with an increase in amount of n-heptane. The correlation obtained for size with concentration will be useful in asphaltene precipitation models. (author)

  1. An experimental study of asphaltene particle sizes in n-heptane-toluene mixtures by light scattering

    Directory of Open Access Journals (Sweden)

    Rajagopal K.

    2004-01-01

    Full Text Available The particle size of asphaltene flocculates has been the subject of many recent studies because of its importance in the control of deposition in petroleum production and processing. We measured the size of asphaltene flocculates in toluene and toluene - n-heptane mixtures, using the light-scattering technique. The asphaltenes had been extracted from Brazilian oil from the Campos Basin, according to British Standards Method IP-143/82. The asphaltene concentration in solution ranged between 10-6 g/ml and 10-7 g/ml. Sizes was measured for a period of about 10000 minutes at a constant temperature of 20°C. We found that the average size of the particles remained constant with time and increase with an increase in amount of n-heptane. The correlation obtained for size with concentration will be useful in asphaltene precipitation models.

  2. Comparative Morphological Study of Asphaltenes in Cuban Crude Using N-Pentane and N-Hexane as Precipitating Agent

    Directory of Open Access Journals (Sweden)

    Doramis de la Caridad Vega Torres

    2015-07-01

    Full Text Available The components of petroleum are grouped into four organic classes such as: Saturated, Aromatic,Resins and Asphaltenes. Asphaltenes are compounds with a complex structure and high molecularweight, made up by carbon rings linked to alkyl chains and cycloalkanes in addition to heterocycliccompounds with. Nitrogen, Sulphur, and Oxygen. Their precipitation of compounds is associated withprocess of production, transportation and refining of crude oil. Recent studies have proved that asphalteneprecipitates vary depending on the precipitating agent used. The research objective in this study isdeveloping a comparative morphological evaluation to asphaltene samples in crude oils from Seboruco,Santa Cruz, Cabaña and Pina. The asphalting precipitations were obtained employed ASTMD-6560-00,using n-pentane and n-hexane as precipitation agents. It was characterized through the use of a ScanningElectron Microscope using 20 KV acceleration. Solids made up by overlapping flakes linked toform agglomerates were obtained with n-hexane and solids with a higher porosity were obtained withn-pentane. Such behavior is attributed to the occupied spaces where resins were initially. The quantityof precipitate that was obtained with n-pentane is higher than the one obtained with the use of n-hexane.

  3. Preliminary results on molecular modeling of asphaltenes using structure elucidation programs in conjunction with molecular simulation programs

    Energy Technology Data Exchange (ETDEWEB)

    Kowalewski, I.; Vandenbroucke, M.; Huc, A.Y.; Taylor, M.J.; Faulon, J.L. [Institut Francais du Petrole, Rueil-Malmaison (France). Division Geologie-Geochimie

    1996-01-01

    Molecular modeling using structure elucidation programs in conjunction with molecular simulation programs has been performed on asphaltene molecules, the heaviest fraction of crude oil, in order to obtain a chemical model allowing the tentative study of their physicochemical properties. Boscan asphaltenes (Venezuela) derived from a marine source rock have been analysed. The different steps of this molecular modeling are described. First, a 3-D chemical representation of Boscan asphaltene is defined from an analytical data set. Second, the results of molecular dynamic simulations indicate that only a few stable conformations are possible due to the high reticulation of the model of the asphaltene unit obtained. 42 refs., 6 figs., 9 tabs.

  4. Molecular mechanics and microcalorimetric investigations of the effects of molecular water on the aggregation of asphaltenes in solutions

    DEFF Research Database (Denmark)

    Murgich, J.; Lira-Galeana, C.; Garcia, Daniel Merino

    2002-01-01

    The interaction of two model asphaltene molecules from the Athabasca sand oil with a water molecule in a toluene solution was studied by means of molecular mechanics calculations. It was found that water forms bridging H bonds between the heteroatoms of asphaltenes with a considerable span...... in energies. The stronger H bond found has energies higher than those corresponding to the stacking of the aromatic areas of the same asphaltene molecules. This shows that the water molecule may generate additional mechanisms of aggregation of asphaltenes in toluene solution, as found experimentally. The H...... bond mechanism depends on the heteroatoms involved, the extension of the aromatic regions, and the steric interference present in the asphaltene molecules. The simulation results have been compared with experimental values of enthalpy of association of two different petroleum asphaltenes obtained...

  5. Asphaltene based photovoltaic devices

    Energy Technology Data Exchange (ETDEWEB)

    Chianelli, Russell R.; Castillo, Karina; Gupta, Vipin; Qudah, Ali M.; Torres, Brenda; Abujnah, Rajib E.

    2016-03-22

    Photovoltaic devices and methods of making the same, are disclosed herein. The cell comprises a photovoltaic device that comprises a first electrically conductive layer comprising a photo-sensitized electrode; at least one photoelectrochemical layer comprising metal-oxide particles, an electrolyte solution comprising at least one asphaltene fraction, wherein the metal-oxide particles are optionally dispersed in a surfactant; and a second electrically conductive layer comprising a counter-electrode, wherein the second electrically conductive layer comprises one or more conductive elements comprising carbon, graphite, soot, carbon allotropes or any combinations thereof.

  6. Modélisation de la combustion de fuels lourds prenant en compte la dispersion des asphaltènes Modeling Heavy Fuel-Oil Combustion (While Considering Or Including Asphaltene Dispersion

    Directory of Open Access Journals (Sweden)

    Audibert F.

    2006-11-01

    difficultés relevant du mode d'exploration et de la non adéquation entre les structures asphalténiques et fractales. On a finalement opté pour une détermination visuelle s'appuyant sur les clichés sur lesquels les agglomérats d'asphaltènes sont clairement visualisés tels qu'ils sont dans le fuel. Ce mode d'exploration laborieux a cependant permis de déterminer un modèle construit sur une série de 25 fuels dont 10 ont été brûlés sur une chaudière de 2 MW, et 15 sur un four de 100 kW. Ce modèle fait intervenir les teneurs en carbone Conradson et en métaux, ainsi que le taux de dispersion des asphaltènes. Le perfectionnement des moyens d'exploration aidant, on peut s'attendre à ce que soient disponibles des techniques d'évaluation de la dispersion sur les clichés. Ce paramètre pourra alors être pris en considération pour une meilleure prédiction de résultats de combustion insuffisamment expliqués avec les paramètres classiques. Various models aiming to predict the amount of unburned particles (solids during heavy fuel-oil combustion have been developed. The parameters taken into consideration are generally asphaltenes precipitated by normal heptane or pentane and Conradson carbon as well as the metals content having a known catalytic effect on cenosphere combustion in the combustion chamber. The Exxon and Shell models can be mentioned, which were developed respectively in 1979 and 1981 (Chapter II. Other models also give consideration to the fuel-oil composition, the way it is atomized and diffused in the chamber and the combustion kinetics (research done by the MIT Energy Laboratory published in 1986. However, the above parameters are not the only ones involved. For some fuel oils, experience has shown that the state of dispersion of asphaltenes may also play an important role particularly for combustion installations with mechanical injection for which the dispersion of fuel-oil droplets is not very great and does not affect the structures built

  7. Optimization of asphaltenes decantation equipment used in deasphalting process using computational fluid dynamics; Otimizacao de um equipamento para a decantacao de asfaltenos no processo de desasfaltacao usando fluidodinamica computacional

    Energy Technology Data Exchange (ETDEWEB)

    Arenales, Carlos Gregorio Dallos [Cooperativa de Trabajadores Profesionales Ltda (CTP), Santander (Colombia); Pimiento, Carlos Eduardo Lizcano; Quintero, Lina Constanza Navarro; Bueno, Jhon Ivan Penaloza [Empresa Colombiana de Petroleos S.A. (ICP/ECOPETROL), Santander (Colombia). Instituto Colombiano del Petroleo

    2012-07-01

    Heavy crude oil is a complex mixture of compounds that include saturates, aromatics, resins and asphaltenes. In this mixture, the asphaltenes are the heaviest components and can be unstable and precipitate. This kind of components causes troubles in transportation and processing. One way to reduce this problem is through technologies that use solvents, which under adequate operating conditions, separate the heavy fraction, improving the properties and conditions for transporting and refining of heavy crude oil. One of the processes used in the petroleum industry to improve the properties of heavy and residue oil is the solvent deasphalting. These processes have the disadvantage of work at elevated pressure and temperature. The Colombian Petroleum Company, ECOPETROL S.A. has developed its own process of upgrading heavy oils, ECODESF, a process that is designed to work at moderate conditions of pressure and temperature and that by using a paraffinic solvent, significantly improves the quality of heavy oil, reducing its viscosity and increasing API gravity. The present work develops a model of computational fluid dynamics (CFD) for asphaltene settler, using microscopic balance. The response of this model allowed determine: the solids flow pattern distribution and accumulation points of heavy phase. This information is useful for understanding the fluid-dynamic behavior of the system. The model was validated using data from a pilot plant with capacity for treatment 1.25 BPD of heavy crude oil. This pilot plant is located in the Colombian Petroleum Institute of ECOPETROL (ICP), Piedecuesta city, Santander, Colombia. (author)

  8. Prediction of the Gas Injection Effect on the Asphaltene Phase Envelope

    Directory of Open Access Journals (Sweden)

    Bahrami Peyman

    2015-11-01

    Full Text Available Asphaltene instability may occur when pressure, temperature and compositional variations affect the reservoir oil. Permeability reduction, wettability alteration, and plugging of wells and flow lines are the consequences of this phenomenon. Therefore, it is crucial to investigate the asphaltene behavior in different thermodynamic conditions by knowing the Asphaltene Precipitation Envelope (APE in a preventive way rather than the costly clean-up procedures. The selected reservoir oil has faced a remarkable decline in production due to several years of extraction, and Enhanced Oil Recovery (EOR has been considered as a solution. Therefore, in this paper, a comprehensive study was carried out to predict the effects of different injected gases on asphaltene onset and to prevent future asphaltene precipitation based on the laboratory data. The Advanced Redlich-Kwong-Soave (RKSA equation of state was considered to develop APE using Multiflash (Infochem Co.. For the selected reservoir oil, with temperature reduction at low temperatures, asphaltene precipitation weakened and made the onset pressure decrease, so this behavior is different from the results obtained in other published reports. On the basis of this model, several sensitivity analyses were performed with different gases (i.e., methane, CO2, N2 and associated gases to compare the risk of each gas for future EOR strategies. APE tend to expand as the amount of injected gases increases, except for CO2 gas injection, that showed another unconventional behavior for this crude oil. It was observed that for CO2 gas injection below a certain temperature, asphaltene stability increased, which can be considered as a good inhibitor of asphaltene precipitation.

  9. NMR and Chemometric Characterization of Vacuum Residues and Vacuum Gas Oils from Crude Oils of Different Origin

    Directory of Open Access Journals (Sweden)

    Jelena Parlov Vuković

    2015-03-01

    Full Text Available NMR spectroscopy in combination with statistical methods was used to study vacuum residues and vacuum gas oils from 32 crude oils of different origin. Two chemometric metodes were applied. Firstly, principal component analysis on complete spectra was used to perform classification of samples and clear distinction between vacuum residues and vacuum light and heavy gas oils were obtained. To quantitatively predict the composition of asphaltenes, principal component regression models using areas of resonance signals spaned by 11 frequency bins of the 1H NMR spectra were build. The first 5 principal components accounted for more than 94 % of variations in the input data set and coefficient of determination for correlation between measured and predicted values was R2 = 0.7421. Although this value is not significant, it shows the underlying linear dependence in the data. Pseudo two-dimensional DOSY NMR experiments were used to assess the composition and structural properties of asphaltenes in a selected crude oil and its vacuum residue on the basis of their different hydrodynamic behavior and translational diffusion coefficients. DOSY spectra showed the presence of several asphaltene aggregates differing in size and interactions they formed. The obtained results have shown that NMR techniques in combination with chemometrics are very useful to analyze vacuum residues and vacuum gas oils. Furthermore, we expect that our ongoing investigation of asphaltenes from crude oils of different origin will elucidate in more details composition, structure and properties of these complex molecular systems.

  10. Calorimetric Evidence about the Application of the Concept of CMC to Asphaltene Self-Association

    DEFF Research Database (Denmark)

    Garcia, Daniel Merino; Andersen, Simon Ivar

    2005-01-01

    For many years, the concept of critical micellar concentration (CMC) has been projected from surfactant science into asphaltene science. There are several similarities between these two species, such as the stabilization of water-in-oil emulsions and surface activity, which suggested that asphalt......For many years, the concept of critical micellar concentration (CMC) has been projected from surfactant science into asphaltene science. There are several similarities between these two species, such as the stabilization of water-in-oil emulsions and surface activity, which suggested...... that asphaltenes may also have a concentration at which self-association occurs (CMC). This article presents evidence found by calorimetry and spectroscopic techniques, that suggest that this concept may not be adequate for asphaltene self-association in toluene solutions. Isothermal titration calorimetry has been...

  11. Aggregation of model asphaltenes: a molecular dynamics study

    Science.gov (United States)

    Costa, J. L. L. F. S.; Simionesie, D.; Zhang, Z. J.; Mulheran, P. A.

    2016-10-01

    Natural asphaltenes are defined as polyaromatic compounds whose chemical composition and structure are dependent on their geological origin and production history, hence are regarded as complex molecules with aromatic cores and aliphatic tails that occur in the heaviest fraction of crude oil. The aggregation of asphaltenes presents a range of technical challenges to the production and processing of oil. In this work we study the behaviour of the model asphaltene-like molecule hexa-tert-butylhexa-peri-hexabenzocoronene (HTBHBC) using molecular dynamics simulation. It was found that the regular arrangement of the tert-butyl side chains prevents the formation of strongly-bound dimers by severely restricting the configurational space of the aggregation pathway. In contrast, a modified molecule with only 3 side chains is readily able to form dimers. This work therefore confirms the influence of the molecular structure of polyaromatic compounds on their aggregation mechanism, and reveals the unexpected design rules required for model systems that can mimic the behavior of asphaltenes.

  12. FORMULASI DAN UJI KINERJA ASPHALTENE DISSOLVER DENGAN PENGGUNAAN SURFAKTAN ANIONIK DARI MINYAK SAWIT

    Directory of Open Access Journals (Sweden)

    Felga Zulfia Rasdiana

    2017-07-01

    Full Text Available Asphaltene deposition is a major problem in petroleum industry causing slow production or even operational shutdown for removal of deposits. This research was conducted to obtain the best formulation of asphaltene dissolver to dissolve asphaltene deposits with the use of an palm oil anionic surfactant and to obtain performance information of asphaltene dissolver formula. The tested formulation were methyl ester sulfonate acid (MESA and methyl ester sulfonate (MES, each with concentrations of 0%, 1%, 3%, and 5% in toluene mixed at a temperature of 40°C for 30 minutes. The best asphaltene dissolver produced was MESA 1% in toluene with the lowest interfacial tension (IFT value of 3.95E-03 dyne/cm and solubility degree of 69.58%. Asphaltene dissolver produced showed a good performance in changing the wettability of rocks with an increase on contact angle of 48,6o to 80,89o , and increase wettability on metal surface with asphaltene release of 99.32% as well as showed good performance on dispersion, desorption and filtration.

  13. Integration of asphaltenes flocculation modeling into Athos reservoir simulator; Integration d'un modele de floculation des asphaltenes dans le simulateur de gisement Athos

    Energy Technology Data Exchange (ETDEWEB)

    Behar, E.; Mougin, P.; Pina, A. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France)

    2003-07-01

    To respond to the ever-growing needs of reservoir simulation studies in a large range of applications, it has been considered necessary to integrate an asphaltenes flocculation model into the Athos software. Athos is a multipurpose simulator which provides a lot of different physical options. Operating companies wish to have available predictive tools, allowing them to plan a reservoir production when the asphaltenic crude it contains could induce porosity and permeability reduction. These companies can thus plan pressure maintenance technologies in order to avoid risks related to asphaltenes flocculation out of the reservoir crude. In the case of deep offshore reservoirs, the economic consequences of such strategies can be of primary importance. The work presented here describes procedures which have been implemented in order to compute asphaltene flocculation conditions within the Athos software. It is thus possible to determine the amount of asphaltenes deposit at different stages of a reservoir or of afield development. This would obviously improve the knowledge of porosity and permeability variation as a result of asphaltenes flocculation, and thus lead to a more reliable evaluation of the oil production. (authors)

  14. Study on the dipole moment of asphaltene molecules through dielectric measuring

    KAUST Repository

    Zhang, Long Li

    2015-01-01

    The polarity of asphaltenes influences production, transportation, and refining of heavy oils. However, the dipole moment of asphaltene molecules is difficult to measure due to their complex composition and electromagnetic opaqueness. In this work, we present a convenient and efficient way to determine the dipole moment of asphaltene in solution by dielectric measurements alone without measurement of the refractive index. The dipole moment of n-heptane asphaltenes of Middle East atmospheric residue (MEAR) and Ta-He atmospheric residue (THAR) are measured within the temperature range of -60°C to 20°C. There is one dielectric loss peak in the measured solutions of the two types of asphaltene at the temperatures of -60°C or -40°C, indicating there is one type of dipole in the solution. Furthermore, there are two dielectric loss peaks in the measured solutions of the two kinds of asphaltene when the temperature rises above -5°C, indicating there are two types of dipoles corresponding to the two peaks. This phenomenon indicates that as the temperature increases above -5°C, the asphaltene molecules aggregate and present larger dipole moment values. The dipole moments of MEAR C7-asphaltene aggregates are up to 5 times larger than those before aggregation. On the other hand, the dipole moments of the THAR C7-asphaltene aggregates are only 3 times larger than those before aggregation. It will be demonstrated that this method is capable of simultaneously measuring multi dipoles in one solution, instead of obtaining only the mean dipole moment. In addition, this method can be used with a wide range of concentrations and temperatures.

  15. Investigating molecular interactions and surface morphology of wax-doped asphaltenes.

    Science.gov (United States)

    Pahlavan, Farideh; Mousavi, Masoumeh; Hung, Albert; Fini, Ellie H

    2016-04-07

    The nature and origin of bee-like microstructures (bees) in asphalt binders and their impact on asphalt oxidation have been the subject of extensive discussions in recent years. While several studies refer to the bees as solely surface features, some others consider them to be bulk microcrystalline components that are formed due to co-precipitation of wax and asphaltene molecules. In this study, we use a rigorous theoretical and experimental approach to investigate the interplay of asphalt components (mainly asphaltene and wax) and their impact on bee formation. In the theoretical section, quantum-mechanical calculations using density functional theory (DFT) are used to evaluate the strength of interactions between asphaltene unit sheets in the presence and absence of a wax component, as well as the mutual interactions between asphaltene molecules (monomers and dimers) and paraffin wax. The results of this section reveal that paraffin waxes not only do not reinforce the interaction between the asphaltene unit sheets, they destabilize asphaltene assembly and dimerization. AIM (Atom in Molecules) analysis shows the destabilizing effect of wax on asphaltene assembly as a reduction in the number of cage and bond critical points between asphaltenes. This destabilization effect among interacting systems (asphaltene-asphaltene and wax-asphaltene) does not support the hypothesis that interaction between paraffin waxes and non-wax components, such as asphaltene, is responsible for their co-precipitation and bee formation. To further examine the effect of wax component on asphalt microstructure experimentally, we used atomic force microscopy (AFM) to study the surface morphology of an asphalt sample doped with 1% to 25% paraffin wax. In agreement with the conclusions drawn from the DFT approach, our experiments indicate that paraffin wax tends to crystallize separately and form lamellar paraffin wax crystal inclusions with 10 nm thickness. Moreover, the addition of 3% wax

  16. Fuel and fuel blending components from biomass derived pyrolysis oil

    Science.gov (United States)

    McCall, Michael J.; Brandvold, Timothy A.; Elliott, Douglas C.

    2012-12-11

    A process for the conversion of biomass derived pyrolysis oil to liquid fuel components is presented. The process includes the production of diesel, aviation, and naphtha boiling point range fuels or fuel blending components by two-stage deoxygenation of the pyrolysis oil and separation of the products.

  17. Oil migration in 2-component confectionery systems.

    Science.gov (United States)

    Lee, Winston L; McCarthy, Michael J; McCarthy, Kathryn L

    2010-01-01

    Oil migration from high oil content centers into chocolate coatings results in product quality changes. The objective of this study was to monitor and model peanut oil migration in 2-layer systems of increasing phase complexity. Three 2-layer systems were prepared: peanut oil/cocoa butter; peanut butter paste/cocoa butter; and peanut butter paste/chocolate. Magnetic resonance imaging was used to measure liquid oil signal as a function of position over a storage time of 193 days at 25 degrees C. The 3 types of samples exhibited appreciably different patterns of oil migration. The peanut oil/cocoa butter samples had mass transfer typical of oil being absorbed into a liquid/solid region. The peanut butter paste/cocoa butter magnetic resonance profiles were characterized by mass transfer with a partition coefficient greater than unity. The peanut butter paste/chocolate samples exhibited a time-dependent peanut oil concentration at the interface between the chocolate and peanut butter paste. The spatial and temporal experimental data of the peanut butter paste/chocolate samples were modeled using a Fickian diffusion model, fitting for the effective diffusivity. Values of the diffusivity for the 6 chocolate formulations ranged from 1.10 to 2.01 x 10(-13) m(2)/s, with no statistically significant differences.

  18. Molecular mechanics and microcalorimetric investigations of the effects of molecular water on the aggregation of asphaltenes in solutions

    DEFF Research Database (Denmark)

    Murgich, J.; Lira-Galeana, C.; Garcia, Daniel Merino;

    2002-01-01

    by titration calorimetry. A simple dimer dissociation model was used to derive the information about the heat and the constant of dissociation from asphaltenes of Mexico and Alaska obtained from the calorimetric data. The association enthalpies calculated were found to be in excellent agreement with those......The interaction of two model asphaltene molecules from the Athabasca sand oil with a water molecule in a toluene solution was studied by means of molecular mechanics calculations. It was found that water forms bridging H bonds between the heteroatoms of asphaltenes with a considerable span...... in energies. The stronger H bond found has energies higher than those corresponding to the stacking of the aromatic areas of the same asphaltene molecules. This shows that the water molecule may generate additional mechanisms of aggregation of asphaltenes in toluene solution, as found experimentally. The H...

  19. Kinetic studies on the pyrolysis of asphaltenes from differenttypes of kerogens

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The pyrolysis kinetics of a series of asphaltenes, from different types of kerogens, are studied in this work. The results indicate that the distributions of activation energy are over a wide range for the asphaltenes from type I kerogens. There is still a large potential of hydrocarbon generation in case the activation energy is above 350 kJ·mol-1. While the distributions of activation energy are comparatively over a narrow range for the asphaltenes from type II and II kerogens,there is a little or almost no potential of hydrocarbon generation with the activation energy above 350 kJ·mol-1 respectively. For the asphaltenes from some specific type of kerogens, the pyrolysis kinetics can be applied to marking their maturity. Furthermore, based on detailed discussions of the kinetics parameter frequency factor, the asphaltenes from type I kerogens are considered to be of great potential to regenerate oils, while the asphaltenes' potential for oil-to-gas conversion tends to go down in order of primitive kerogen types of Ⅲ II and I.

  20. Removal of asphaltene and paraffin deposits using micellar solutions and fused reactions. Final report, 1995--1997

    Energy Technology Data Exchange (ETDEWEB)

    Chang, C.L.; Nalwaya, V.; Singh, P.; Fogler, H.S.

    1998-05-01

    Chemical treatments of paraffin and asphaltene deposition by means of cleaning fluids were carried out in this research project. Research focused on the characterization of asphaltene and paraffin materials and dissolution of asphaltene and paraffin deposits using surfactant/micellar fluids developed early in the project. The key parameters controlling the dissolution rate were identified and the process of asphaltene/paraffin dissolution were examined using microscopic apparatus. Numerical modeling was also carried out to understand the dissolution of paraffin deposits. The results show that fused chemical reaction systems are a promising way of removing paraffin deposits in subsea pipelines. The fused system may be in the form of alternate pulses, emulsions systems or encapsulated catalyst systems. Fused reaction systems, in fact, are extremely cost-effective--less than 10% of the cost of replacing entire sections of the blocked pipeline. The results presented in this report can have a real impact on the petroleum industry and the National Oil Program, if it is realized that the remediation technologies developed here can substantially delay abandonment (due to asphaltene/paraffin plugging) of domestic petroleum resources. The report also sheds new light on the nature and properties of asphaltenes and paraffin deposits which will ultimately help the scientific and research community to develop effective methods in eliminating asphaltene/paraffin deposition problems. It must also be realized that asphaltene remediation technologies developed and presented in this report are a real alternative to aromatic cleaning fluids currently used by the petroleum industry.

  1. Chemical Components of Four Essential Oils in Aromatherapy Recipe.

    Science.gov (United States)

    Tadtong, Sarin; Kamkaen, Narisa; Watthanachaiyingcharoen, Rith; Ruangrungsi, Nijsiri

    2015-06-01

    This study focused on characterization of the chemical components of an aromatherapy recipe. The formulation consisted of four blended essential oils; rosemary oil, eucalyptus oil, pine oil and lime oil (volume ratio 6 : 2 : 1 : 1). The single and combination essential oils were identified by gas chromatography-mass spectrometry (GC-MS). The analysis of GC-MS data revealed that several components exist in the mixture. The five most important components of the blended essential oils were 1,8-cineole (35.6 %), α-pinene (11.1%), limonene (9.6%), camphor (8.4%), and camphene (6.6%). The main components of rosemary oil were 1,8-cineole (37.3%), α-pinene (19.3%), camphor (14.7%), camphene (8.8%), and β-pinene (5.5%); of eucalyptus oil 1,8-cineole (82.6%) followed by limonene (7.4%), o-cymene (4.3%), γ-terpinene (2.7%), and α-pinene (1.5%); of pine oil terpinolene (26.7%), α-terpineol (20.50%), 1-terpineol (10.8%), α-pinene (6.0%), and γ-terpineol (5.3%); and of lime oil limonene (62.9%), γ-terpinene (11.5%), α-terpineol (7.6%), terpinolene (6.0%), and α-terpinene (2.8%). The present study provided a theoretical basis for the potential application of blended essential oils to be used as an aromatherapy essential oil recipe. GC-MS serves as a suitable and reliable method for the quality control of the chemical markers.

  2. Hydrogen bonding in asphaltenes and coal. Progress report, April 1, 1978--June 30, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Li, N.C.; Tewari, K.C.

    1978-06-01

    A direct calorimetric method has been used to determine simultaneously the molar enthalpy, ..delta..H/sup 0/, and equilibrium constant, K, for quinoline (QU) interaction with coal-derived asphaltenes (A), acid/neutral (AA) and base (BA) components of A, silylated asphaltenes (A(TMS)) and heavy oil (HO) fractions in solvent C/sub 6/H/sub 6/. Solvent fractionated A and HO fractions were from three centrifuged liquid product (CLP) samples prepared in the 450 kg (/sup 1///sub 2/ ton) per-day Process Development Unit at Pittsburgh Energy Research Center, at different process conditions from the same feed coal, Kentucky hvAb. For a given system, Qu-A (AA or BA), Qu-HO, the almost constant value of K and linear variation of ..delta..H/sup 0/ with the phenolic oxygen content of coal liquid fractions, have been attributed to the dominance of hydrogen-bonding effects, involving phenolic OH, over other types of molecular interactions in solution. In Qu-A(TMS) system, -..delta..H/sup 0/ values increase with decrease in molecular weight of A(TMS), while -..delta..S/sup 0/ values increase with increase in aromaticity of A fraction. The degree of complexation, in absence of OH groups, is much smaller than Qu-A system and largely depends upon some unusual entropy effects.

  3. CHARACTERIZATION OF POLAR COMPONENTS IN HYTROTREATED NAPHTHENIC RUBBER PROCESS OIL

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Polar components play a very important role toward light stability of hydrotreated naphthenic rubber process oil. Polar components in hydrotreated naphthenic rubber process oil are analyzed in detail. Polar components are firstly isolated from rubber process oil by column chromatography of silica gel, and then characterized by a series of instrument technology including elemental analysis, infrared spectroscopy, APCI/MS and XPS. The results show that the polar components comprise some hetero atoms compounds of sulfur, nitrogen and oxygen. Oxygen- containing compounds such as hydroxyl, carbonyl, and carboxyl groups constitute the main body of polar components. Nitrogen - containing compounds (NH2, NH, or NO2 and - N = N - ) and sulfur - containing compounds (SO42- and PHSSPH) only account for minor percent of polar components. The molecular weight distribution of polar components mainly concentrates between 300 and 500 and a minor portion distributes from 180 to 300.

  4. Analysis of minor components in olive oil.

    Science.gov (United States)

    Murkovic, Michael; Lechner, Sonja; Pietzka, Ariane; Bratacos, Michael; Katzogiannos, Evangellos

    2004-10-29

    Virgin olive oil is well known for its high content of phenolic substances that are thought to have health-promoting properties. These substances also contribute to the distinctive taste of the oil. In this study, tyrosol, vanillic acid, luteolin, and apigenin were identified and quantified by liquid chromatography mass spectrometry (LC-MS). In the seven samples analysed, tyrosol, the most abundant, was in the range of 1.4-29 mg/kg, vanillic acid was in the range of 0.67-4.0 mg/kg, luteolin was in the range of 0.22-7.0 mg/kg, and apigenin was in the range of 0.68-1.6 mg/kg. It was also shown that in olive oil, squalene can be analysed by using a refractive index detector. In the samples analysed, squalene occurred in the range of 3.9-9.6 g/l.

  5. 21 CFR 181.26 - Drying oils as components of finished resins.

    Science.gov (United States)

    2010-04-01

    ...) shall include: Chinawood oil (tung oil). Dehydrated castor oil. Linseed oil. Tall oil. [42 FR 14638, Mar... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Drying oils as components of finished resins. 181... Prior-Sanctioned Food Ingredients § 181.26 Drying oils as components of finished resins. Substances...

  6. Characterization and comparison of the pungent components in commercial Zanthoxylum bungeanum oil and Zanthoxylum schinifolium oil.

    Science.gov (United States)

    Zhao, Zhi-Feng; Zhu, Rui-Xue; Zhong, Kai; He, Qiang; Luo, Ai-Min; Gao, Hong

    2013-10-01

    In the present study, the characterization and comparison of the pungent components in commercial Z. bungeanum oils and Z. schinifolium oils were investigated. By high-performance liquid chromatography (HPLC)-mass spectrometry (MS/MS) analysis, the major alkylamides in Z. bungeanum and Z. schinifolium oils were identified as hydroxy-ε-sanshool, hydroxy-α-sanshool, hydroxy-β-sanshool, hydroxy-γ-sanshool, hydroxy-γ-isosanshool, bungeanool, isobungeanool, and tetrahydrobungeanool, respectively. Hydroxy-α-sanshool was found to be the most abundant alkylamide in all oils. The levels of hydroxy-ε-sanshool and hydroxy-β-sanshool in Z. bungeanum oils were comparable to that in Z. schinifolium oils, whereas Z. bungeanum oils contained significantly (P less than 0.05) higher levels of hydroxy-γ-isosanshool, bungeanool, isobungeanool, and tetrahydrobungeanool, compared with Z. schinifolium oils. Furthermore, principal component analysis (PCA) indicated that Z. bungeanum oil and Z. schinifolium oil were clearly classified by HPLC fingerprinting profiles and concentrations of alkylamides. In addition, the results of PCA suggested that alkylamides, such as hydroxy-γ-sanshool and bungeanool, could be potential markers to distinguish Z. bungeanum oil and Z. schinifolium oil. The results from this study could be used to discriminate the different flavor characterization and control the quality of commercial Z. bungeanum oil and Z. schinifolium oil.

  7. Experimental Study and Mathematical Modeling of Asphaltene Deposition Mechanism in Core Samples

    Directory of Open Access Journals (Sweden)

    Jafari Behbahani T.

    2015-11-01

    Full Text Available In this work, experimental studies were conducted to determine the effect of asphaltene deposition on the permeability reduction and porosity reduction of carbonate, sandstone and dolomite rock samples using an Iranian bottom hole live oil sample which is close to reservoir conditions, whereas in the majority of previous work, a mixture of recombined oil (a mixture of dead oil and associated gas was injected into a core sample which is far from reservoir conditions. The effect of the oil injection rate on asphaltene deposition and permeability reduction was studied. The experimental results showed that an increase in the oil injection flow rate can result in an increase in asphaltene deposition and permeability reduction. Also, it can be observed that at lower injection flow rates, a monotonic decrease in permeability of the rock samples can be attained upon increasing the injection flow rate, while at higher injection rates, after a decrease in rock permeability, an increasing trend is observed before a steady-state condition can be reached. The experimental results also showed that the rock type can affect the amount of asphaltene deposition, and the asphaltene deposition has different mechanisms in sandstone and carbonate core samples. It can be seen that the adsorption and plugging mechanisms have a more important role in asphaltene deposition in carbonate core samples than sandstone core samples. From the results, it can be observed that the pore volumes of the injected crude oil are higher for sandstone cores compared with the carbonate cores. Also, it can be inferred that three depositional types may take place during the crude oil injection, i.e., continuous deposition for low-permeability cores, slow, steady plugging for high-permeability cores and steady deposition for medium-permeability cores. It can be seen from the experimental results that damage to the core samples was found to increase when the production pressures were

  8. Asphaltene Formation Damage Stimulation by Ultrasound: An Analytical Approach Using Bundle of Tubes Modeling

    Directory of Open Access Journals (Sweden)

    Arash Rabbani

    2015-01-01

    Full Text Available This study presents a novel approach for bundle of tubes modeling of permeability impairment due to asphaltene-induced formation damage attenuated by ultrasound which has been rarely attended in the available literature. Model uses the changes of asphaltene particle size distribution (APSD as a function of time due to ultrasound radiation, while considering surface deposition and pore throat plugging mechanisms. The proposed model predicts the experimental data of permeability reduction during coinjection of solvent and asphaltenic oil into core with reasonable agreement. Viscosity variation due to sonication of crude oil is used to determine the fluid mobility applied in the model. The results of modeling indicate that the fluid samples exposed to ultrasound may cause much less asphaltene-induced damage inside the porous medium. Sensitivity analysis of the model parameters showed that there is an optimum time period during which the best stimulation efficiency is observed. The results of this work can be helpful to better understand the role of ultrasound prohibition in dynamic behavior of asphaltene deposition in porous media. Furthermore, the present model could be potentially utilized for modeling of other time-dependent particle induced damages.

  9. Adsorption of ethyl cellulose on asphaltene- or bitumen-coated hydrophilic silica surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shengqun; Segin, Nataliya; Wang, Ke; Masliyah, Jacob H.; Xu, Zhenghe [Department of Chemical and Materials Engineering, University of Alberta (Canada)], email: zhenghe.xu@ualberta.ca

    2010-07-01

    Previous studies show that ethyl cellulose (EC) is a biodegradable, greener demulsifier for water-oil emulsions that significantly reduces diluted bitumen-water interfacial tension. In this study, the molecular mechanism of EC demulsifiers is investigated using an atomic force microscope (AFM) and a quartz crystal microbalance (QCM). Asphaltenes and bitumen were adsorbed from toluene on a hydrophilic silica wafer, which was soaked in an EC-in-toluene solution for varying periods of time. The EC gradually displaced the asphaltene/bitumen aggregates, pushing them into larger aggregates. The process reached equilibrium in about 7 hours, with EC covering most of the silica surface with large, sporadically scattered aggregates. The EC-dominated surface became more hydrophilic than asphaltene/bitumen-adsorbed surfaces. The QCM study showed that the displacement of pre-adsorbed asphaltenes by EC is irreversible. The affinity of EC to hydrophilic silica surface is stronger than that of asphaltenes, providing further insights into demulsification mechanisms of EC for breaking w/o emulsions. EC also has potential in altering a solid from oil-wet to water-wet.

  10. Microarray analysis of Neosartorya fischeri using different carbon sources, petroleum asphaltenes and glucose-peptone

    Science.gov (United States)

    Hernández-López, Edna L.; Ramírez-Puebla, Shamayim T.; Vazquez-Duhalt, Rafael

    2015-01-01

    Asphaltenes are considered as the most recalcitrant petroleum fraction and represent a big problem for the recovery, separation and processing of heavy oils and bitumens. Neosartorya fischeri is a saprophytic fungus that is able to grow using asphaltenes as the sole carbon source [1]. We performed transcription profiling using a custom designed microarray with the complete genome from N. fischeri NRRL 181 in order to identify genes related to the transformation of asphaltenes [1]. Data analysis was performed using the genArise software. Results showed that 287 genes were up-regulated and 118 were down-regulated. Here we describe experimental procedures and methods about our dataset (NCBI GEO accession number GSE68146) and describe the data analysis to identify different expression levels in N. fischeri using this recalcitrant carbon source. PMID:26484261

  11. New insights into the antioxidant activity and components in crude oat oil and soybean oil.

    Science.gov (United States)

    Chen, Hao; Qiu, Shuang; Gan, Jing; Li, Zaigui; Nirasawa, Satoru; Yin, Lijun

    2016-01-01

    Developing new antioxidants and using natural examples is of current interest. This study evaluated the antioxidant activities and the ability to inhibit soybean oil oxidation of oat oil obtained with different solvents. Oat oil extract obtained by ethanol extraction gave the highest antioxidant activity with a DPPH radical (1,1-diphenyl-2-picrylhydrazyl) scavenging activity of 88.2 % and a reducing power (A 700) of 0.83. Oat oil extracted by ethanol contained the highest polyphenol and α-tocopherol content. Significant correlation was observed between the total polyphenol contents, individual phenolic acid, α-tocopherol, and DPPH radical scavenging activity. Soybean oil with 2 % added oat oil showed low malondialdehyde content (8.35 mmol mL(-1)), suggesting that the added oat oil inhibited oxidation. Oat oil showed good antioxidant activity, especially when extracted with ethanol which could also retard the oxidation of soybean oil . DPPH radical scavenging activity was the best method to evaluate the antioxidant activity and components of oat oil.

  12. Asphaltene-laden interfaces form soft glassy layers in contraction experiments: a mechanism for coalescence blocking.

    Science.gov (United States)

    Pauchard, Vincent; Rane, Jayant P; Banerjee, Sanjoy

    2014-11-04

    In previous studies, the adsorption kinetics of asphaltenes at the water-oil interface were interpreted utilizing a Langmuir equation of state (EOS) based on droplet expansion experiments.1-3 Long-term adsorption kinetics followed random sequential adsorption (RSA) theory predictions, asymptotically reaching ∼85% limiting surface coverage, which is similar to limiting random 2D close packing of disks. To extend this work beyond this slow adsorption process, we performed rapid contractions and contraction-expansions of asphaltene-laden interfaces using the pendant drop experiment to emulate a Langmuir trough. This simulates the rapid increase in interfacial asphaltene concentration that occurs during coalescence events. For the contraction of droplets aged in asphaltene solutions, deviation from the EOS consistently occurs at a surface pressure value ∼21 mN/m corresponding to a surface coverage ∼80%. At this point droplets lose the shape required for validity of the Laplace-Young equation, indicating solidlike surface behavior. On further contraction wrinkles appear, which disappear when the droplet is held at constant volume. Surface pressure also decreases down to an equilibrium value near that measured for slow adsorption experiments. This behavior appears to be due to a transition to a glassy interface on contraction past the packing limit, followed by relaxation toward equilibrium by desorption at constant volume. This hypothesis is supported by cycling experiments around the close-packed limit where the transition to and from a solidlike state appears to be both fast and reversible, with little hysteresis. Also, the soft glass rheology model of Sollich is shown to capture previously reported shear behavior during adsorption. The results suggest that the mechanism by which asphaltenes stabilize water-in-oil emulsions is by blocking coalescence due to rapid formation of a glassy interface, in turn caused by interfacial asphaltenes rapidly increasing in

  13. Hydrogen bonding in asphaltenes and coal. Progress report, March 1, 1977--August 31, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Li, N.C.; Tewari, K.C.

    1977-08-01

    A calorimetric method is presented for the simultaneous evaluation of equilibrium constant, K, and molar enthalpy, ..delta..H/sup 0/, for 1 : 1 adduct formation of quinoline (Qu) with asphaltene (A), together with its acid/neutral (AA) fraction and its base (BA) fraction, isolated from a centrifuged liquid product (CLP) sample prepared from Kentucky hvAb coal at 27.6 MPa hydrogen pressure and 723K, with reactor charged with glass pellets. The same procedure was used to determine K and ..delta..H/sup 0/ for 1 : 1 adduct formation of Qu with asphaltene and heavy oils obtained from CLP samples (FB-53) prepared with CoMo catalyst at different run times and process conditions. The effects of the CoMo catalyst, run time, and residence times on viscosity, molecular weight, ..delta..H/sup 0/, heteratom content, contents of preasphaltene, asphaltene and heavy oil, aromaticity, and structural parameters, are determined. These findings lead to the conclusion that hydrogen bonding plays an important role in determining viscosity, and contributes more to the enthalpy of interaction than does ..pi..-interaction. The toluene-insoluble fraction, asphaltene (whole, acid/neutral and base fractions), and heavy oil were isolated from a solvent-refined-coal (SRC) conversion product. Data obtained from several infrared and viscosity experiments indicate that the behavior of different fractions isolated from SRC is similar to that of corresponding fractions isolated from CLP samples.

  14. Source of 1,2,3,4-tetramethylbenzene in asphaltenes from the Tarim Basin

    Science.gov (United States)

    Wanglu, Jia; Ping'an, Peng; Chiling, Yu; Zhongyao, Xiao

    2007-07-01

    1-Alkyl-2,3,6-trimethylbenzenes and a high relative amount of 1,2,3,4-tetramethylbenzene (TTMB) have been previously detected in the marine oils and asphaltenes in the oils from the Tarim Basin. In the present study, the stable carbon isotopic compositions of TTMB and n-alkanes in the pyrolysates of asphaltenes in the marine oils from the northern Tarim Basin and Silurian tar sands from the Tarim Basin were determined. TTMB has stable carbon isotopic compositions in the range from -23‰ to -24‰ and are about 12‰ more enriched in 13C than concomitant n-alkanes (-35‰ to -37‰) in the pyrolysates. The results indicate a contribution from green sulfur bacteria ( Chlorobiaceae) to TTMB. Thus, the depositional environments of the source rocks for the marine oils and the bitumen in tar sands from the Tarim Basin are characterized by periods of euxinic conditions within the photic zone.

  15. Interactions between Asphaltenes and Water in Solutions in Toluene

    DEFF Research Database (Denmark)

    Khvostichenko, Daria; Andersen, Simon Ivar

    2008-01-01

    Binding of water by asphaltenes dissolved in toluene was investigated for two asphaltene samples, OMV1 and OMV2, from the same reservoir deposit. Solubility of water in asphaltene solutions in toluene was found to increase with an increasing asphaltene concentration, indicative of solubilization...... was determined for water-saturated solutions (OMV1 and OMV2) and for water-unsaturated solutions (OMV1 only). These numbers were found to decrease from several water molecules per asphaltene molecule to below unity upon an increase of the asphaltene concentration in toluene from 0.1 to 20 g/L, suggesting...

  16. Asphaltenes-based polymer nano-composites

    Science.gov (United States)

    Bowen, III, Daniel E

    2013-12-17

    Inventive composite materials are provided. The composite is preferably a nano-composite, and comprises an asphaltene, or a mixture of asphaltenes, blended with a polymer. The polymer can be any polymer in need of altered properties, including those selected from the group consisting of epoxies, acrylics, urethanes, silicones, cyanoacrylates, vulcanized rubber, phenol-formaldehyde, melamine-formaldehyde, urea-formaldehyde, imides, esters, cyanate esters, allyl resins.

  17. Physical chemical characteristics of oil emulsions of North-West Konys and Zhanaozen oilfields

    Directory of Open Access Journals (Sweden)

    Akbota Adilbekova

    2016-06-01

    Full Text Available Physical chemical properties of oil emulsions of two different oilfields of Kazakhstan - NorthWest Konys and Zhanaozen by their densities related to light and heavy oils, respectively, were studied. Qualitative and quantitative compositions of main stabilizing components of oil emulsions (resins, asphaltenes and high molecular paraffins were determined. The dispersion degree of oil emulsions was determined using optical microscopy. It was found that samples relate to fine dispersed oil emulsions by dispersion, and to poorly stable (Konys and highly stable (Zhanaozen oil emulsions by ability to form emulsions. Light oil of Konys oilfield (ρ = 833 kg/m3 at 20°C contains 11.5% of paraffins, 0.69% resins, 0.19% asphaltenes. The same measurements were carried out for heavy oil of Zhanaozen (943 kg/m3 at 20°C where paraffin content exceeded 30%, amount of resins was 1.5% and asphaltenes – 0.6%. The sample of Zhanaozen oilfield contains 33% of water, 154.8 mg/L chlorides, 5.22 % mechanical impurities, and for oilfield samples of North-West Konys the water content was 7.5%, the content of chloride salts – 18 mg/L, and 0.002% of mechanical impurities.

  18. Heavy oil components sorbed onto clay minerals in Canadian oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Fendel, A.; Schwochau, K. (Institute for Petroleum and Organic Geochemistry, Nuclear Research Centre (KFA), Julich (DE))

    1988-06-01

    In siliciclastic reservoir rocks the surface-active clay minerals are presumed to be predominantly responsible for the sorption of polar oil components. In order to achieve a better insight into the nature of the oil components sorbed onto clay minerals, unconsolidated Canadian Oil Sands (Cold Lake, Athabasca) were exhaustively extracted with dichloromethane to remove the free oil. The clay minerals (grain fraction less than or equal to2 ..mu..m) were then separated by gravitational sedimentation. After the extraction up to 3 wt of organic carbon still remained on the clays. The amount of aliphatic carbon adhering to the clays was assessed by means of IR-spectroscopy. The clay minerals were successively extracted with solvent mixtures of increasing polarity in order to release the bound oil components. The extracts were fractionated into chemically defined compound classes by semi-preparative liquid chromatography and MPLC. The fractions were characterized by GC, GC-MS and IR-spectroscopy. Components containing oxygen functions (carboxylic acids, esters, alcohols, ketones) appear to be preferentially bound by clays. Moreover, a small amount of hydrocarbons, in particular saturates, are sorbed by clays.

  19. Evaluation of Reservoir Wettability and its Effect on Oil Recovery.

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, J.S.

    1998-01-15

    We report on the first year of the project, `Evaluation of Reservoir Wettability and its Effect on Oil Recovery.` The objectives of this five-year project are (1) to achieve improved understanding of the surface and interfacial properties of crude oils and their interactions with mineral surfaces, (2) to apply the results of surface studies to improve predictions of oil production from laboratory measurements, and (3) to use the results of this research to recommend ways to improve oil recovery by waterflooding. During the first year of this project we have focused on understanding the interactions between crude oils and mineral surfaces that establish wetting in porous media. As background, mixed-wetting and our current understanding of the influence of stable and unstable brine films are reviewed. The components that are likely to adsorb and alter wetting are divided into two groups: those containing polar heteroatoms, especially organic acids and bases; and the asphaltenes, large molecules that aggregate in solution and precipitate upon addition of n-pentane and similar agents. Finally, the test procedures used to assess the extent of wetting alteration-tests of adhesion and adsorption on smooth surfaces and spontaneous imbibition into porous media are introduced. In Part 1, we report on studies aimed at characterizing both the acid/base and asphaltene components. Standard acid and base number procedures were modified and 22 crude oil samples were tested. Our approach to characterizing the asphaltenes is to focus on their solvent environment. We quantify solvent properties by refractive index measurements and report the onset of asphaltene precipitation at ambient conditions for nine oil samples. Four distinct categories of interaction mechanisms have been identified that can be demonstrated to occur when crude oils contact solid surfaces: polar interactions can occur on dry surfaces, surface precipitation is important if the oil is a poor solvent for its

  20. Influence of containing of asphaltenes and naphthenic acids over organic deposition inhibitor performance

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Geiza E.; Mansur, Claudia R.E.; Pires, Renata V.; Passos, Leonardo B.; Lucas, Elizabete F. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Macromoleculas; Alvares, Dellyo R.S.; Gonzalez, Gaspar [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    Organic deposition is a serious problem confronted by the petroleum industry in Brazil and worldwide. Among the main petroleum components that may cause deposition problems are waxes and asphaltenes. This work aims at evaluating the influence of petroleum fractions (asphaltenes and naphthenic acids) on the organic deposition phenomenon as well as on organic deposition inhibitors performance. The influence of the organic fractions was evaluated by their ability to change wax crystals, to lower the pour point and to alter the initial wax appearance temperature. The efficiency of the additives was tested by pour point measurements. The results show that asphaltenes seem to act as organic deposition inhibitors, while naphthenic acids do not significantly change the system. Moreover, employing both of them produces no synergic effect. Among polymeric inhibitors, all of the chemically modified EVA copolymer presented better results than the non-modified commercial EVA copolymer. The best result was observed for EVA28C{sub 16}. (author)

  1. Chemistry and structure of coal-derived asphaltenes, Phase III. Quarterly progress report, April--June 1978

    Energy Technology Data Exchange (ETDEWEB)

    Yen, T. F.

    1978-01-01

    Solubility parameters may be calculated for coal liquid derived products by use of a semi-empirical relationship between solubility parameter and refractive index. Thermal treatment of Synthoil coal liquid oil + resin solvent fraction at 235 to 300/sup 0/C resulted in the transformation of oil and resin into asphaltene. Further support of structural characterizations was obtained by use of a combined x-ray and NMR structural characterization procedure which relies on the important x-ray structural parameter L/sub a/ (average layer diameter of the aromatic sheet). L/sub a/ values of approx. = 8 to 10 A for asphaltenes, approx. = 13.4 to 14 A for carbenes, and approx. = 14 to 16.5 A for carboids were obtained by the x-ray procedure. These data were used to calculate C/sub Au/ (aromatic carbons per structural unit) and N (number of structural units per molecule) values. For asphaltenes the results agree with those previously deduced from NMR and other techniques. The C/sub Au/ values are generally close to 14 which is the number of aromatic carbons present in a 3-ring kata-system such as anthracene or phenanthrene. The number of structural units per molecule is close to two for all the asphaltenes. Additional data were used to improve the correlation equation between weight percent OH, determined by the silylation method, and the absorbance of the monomeric OH infrared stretching band at 3600 cm/sup -1/ for asphaltenes. A similar correlation between weight percent NH, from elemental analysis of asphaltene samples containing essentially all nitrogen as pyrrolic N-H, and the infrared absorbance of the N-H stretching band at 3470 cm/sup -1/ was developed for asphaltenes.

  2. Hydrogen bonding in asphaltenes and coal. Comprehensive progress report, December 1975--Februray 1977. [13 references

    Energy Technology Data Exchange (ETDEWEB)

    Li, N.C.

    1977-01-01

    Proton magnetic resonance (PMR) studies are reported of hydrogen bonding between the OH proton of o-phenylphenol (OPP) and the nitrogen electron donor of quinoline (Qu). Data are also reported on the hydrogen bonding of a coal-derived asphaltene and its acid and base components with OPP. Determination was made of the equilibrium constants of the 1:1 complex between OPP and Qu at 39, 32, 1, and -18/sup 0/C from the PMR studies. Qualitative results are reported for the interaction between the base fraction of asphaltene and OPP at 32, 1, and -26/sup 0/C.

  3. Investigation of the Gas Injection Effect on Asphaltene Onset Precipitation Using the Cubic-Plus-Association Equation of State

    DEFF Research Database (Denmark)

    Arya, Alay; von Solms, Nicolas; Kontogeorgis, Georgios M.

    2016-01-01

    dependency upon the saturates, aromatics, resins, and asphaltenes (SARA) analysis or molecular weight (MW) of asphaltene is also analyzed. In addition, a unique characteristic of the model for the given stock tank oil (STO) is identified, which does not change with different types and amounts of gas...... injections and also remains the same at upper and lower onset pressure boundaries. On the basis of this unique characteristic, a simple procedure to predict asphaltene phase envelope (APE) for the reservoir oil with relatively simple and few experimental data, performed on STO with n......-pentane/n-heptane as a precipitant, is proposed. This proposed procedure avoids the need of high-pressure measurements of upper onset pressure (UOP)....

  4. Enantiomeric distribution of key volatile components in Citrus essential oils

    Directory of Open Access Journals (Sweden)

    Ivana Bonaccorsi

    2011-10-01

    Full Text Available Citrus as many other plants present characteristic distribution of some enantiomers, thus it is often possible to use this parameter for identification, characterization, genuineness, and pharmacological activity assessment. In particular, it is possible to reveal adulteration of different nature, such as addition of synthetic compounds, or natural components of different botanical origin, with drastic changes in the biological and olfactory properties. This study is focused on the evaluation of the enantiomeric excesses of numerous samples of different Citrus species: C. deliciosa Ten., C. limon (L. Burm., C. bergamia, C. aurantifolia (Christm. Swing., C. latifolia Tan., C. sinensis (L. Osbeck, and C. aurantium L. The enantiomeric distribution is determined by direct esGC and, depending on the complexity of the essential oil, by MDGC with a chiral column in the second dimension. The research is focused on the determination of fourteen chiral components which present specific distribution in the essential oils investigated. Particular attention is given to the trend of the enantiomeric distribution during the productive season, so to identify useful parameters for quality assessment also in consideration of the wide range of variability often reported in literature. The components investigated were the following: α-thujene, α-pinene, camphene, β-pinene, sabinene, α-phellandrene, β-phellandrene, limonene, linalool, camphor, citronellal, linalyl acetate, terpinen-4-ol, α-terpineol. The use of MDGC allowed the separation of the enantiomers of camphor and citronellal, otherwise not separated by conventional esGC; however for the separation of the enantiomers of α-pinene it was preferable to use conventional esGC. The MDGC system allowed to determine the enantiomeric distribution of camphene, α- and β-phellandrene in lime essential oil for the first time. The results are discussed in function of seasonal variation and, when possible, in

  5. Carbonized asphaltene-based carbon-carbon fiber composites

    Energy Technology Data Exchange (ETDEWEB)

    Bohnert, George; Lula, James; Bowen, III, Daniel E.

    2016-12-27

    A method of making a carbon binder-reinforced carbon fiber composite is provided using carbonized asphaltenes as the carbon binder. Combinations of carbon fiber and asphaltenes are also provided, along with the resulting composites and articles of manufacture.

  6. Transport of Organic Oil Components from Immobile and Bypassed Oil in Heterogeneous Porous Media

    Energy Technology Data Exchange (ETDEWEB)

    Huseby, O.; Haugan, A.; Sagen, J.; Muller, J.; Bennett, B.; Larter, S.; Kikkinides, E.S.; Stubos, A.K.; Yousefian, F.; Thovert, J.-F.; Adler, P.M.

    2001-12-01

    An experimental study, as well as theoretical and numerical models, are used to validate a methodology to exploit conventional geochemical data with regard to the concentration profiles of organic components occurring naturally in hydrocarbon reservoir oils. The experiment was designed to study transport of organic compounds from immobile oil during water injection. A homogeneous oil-filled core sample was made heterogeneous by drilling a hole through its central axis and filling it with a highly permeable material. Under the present conditions, diffusion coefficients are the most important parameters controlling the transport, and the effect of partitioning could be accounted for by a simple normalization. The experimental results are well described by a simple 2-D analytical model which assumes instantaneous removal of solutes from the oil-water interface. The experimental results are also well described by two numerical models, of which one is a full featured reservoir scale model, suitable for applications of the methodology to reservoir scale cases. (author)

  7. Transport of Organic Oil Components from Immobile and Bypassed Oil in Heterogeneous Porous Media

    Energy Technology Data Exchange (ETDEWEB)

    Huseby, O.; Haugan, A.; Sagen, J.; Muller, J.; Bennett, B.; Larter, S.; Kikkinides, E.S.; Stubos, A.K.; Yousefian, F.; Thovert, J.-F.; Adler, P.M.

    2001-12-01

    An experimental study, as well as theoretical and numerical models, are used to validate a methodology to exploit conventional geochemical data with regard to the concentration profiles of organic components occurring naturally in hydrocarbon reservoir oils. The experiment was designed to study transport of organic compounds from immobile oil during water injection. A homogeneous oil-filled core sample was made heterogeneous by drilling a hole through its central axis and filling it with a highly permeable material. Under the present conditions, diffusion coefficients are the most important parameters controlling the transport, and the effect of partitioning could be accounted for by a simple normalization. The experimental results are well described by a simple 2-D analytical model which assumes instantaneous removal of solutes from the oil-water interface. The experimental results are also well described by two numerical models, of which one is a full featured reservoir scale model, suitable for applications of the methodology to reservoir scale cases. (author)

  8. Formulas of components of citronella oil against mosquitoes (Aedes aegypti).

    Science.gov (United States)

    Hsu, Wey-Shin; Yen, Jui-Hung; Wang, Yei-Shung

    2013-01-01

    The mosquito Aedes aegypti is an epidemic vector of several diseases such as dengue fever and yellow fever. Several pesticides are used to control the mosquito population. Because of their frequent use, some mosquitoes have developed resistance. In this study, we used the Y-tube olfactometer to test essential oils of Cymbopogon species and screened specific formulas of components as repellents against Ae. aegypti. At 400 μL, the extracted oil of citronella grass (Cymbopogon nardus) and myrcene produced a low-active response by inhibiting mosquito host-seeking activity. Citronella grass, lemon grass (Cymbopogon citratus), citral and myrcene also produced a low-treatment response to repellents, for more potential to affect host-seeking behavior. Furthermore, the mixture of citral, myrcene, and citronellal oil (C:M:Ci = 6:4:1) greatly affected and inhibited host-seeking behavior (76% active response; 26% treatment response with 40 μL; 42.5%, 18% with 400 μL; and 19%, 23% with 1000 μL). As compared with the result for N,N-diethyl-3-methylbenzamide (DEET; 44%, 22% with 400 μL), adjusting the composition formulas of citronella oil had a synergistic effect, for more effective repellent against Ae. aegypti.

  9. Analysis of Asphaltenes Subfractionated by N-Methyl-2-pyrrolidone

    DEFF Research Database (Denmark)

    Ascanius, Birgit Elkjær; Garcia, Daniel Merino; Andersen, Simon Ivar

    2004-01-01

    -pyrrolidone (NMP) as a mobile phase. However, an NMP-insoluble asphaltene fraction of 9-53 wt % was observed for different petroleum n-heptane asphaltenes. Further analysis of the insoluble fraction surprisingly has shown that this fraction hardly exhibits any ultraviolet-visible light absorption...... or fluorescence. This result implies that a substantial fraction of asphaltenes will not be represented in a fluorescence spectrum. This finding may have great implications in the capacity of fluorescence spectroscopy to analyze asphaltenes....

  10. Electrodeposition of Asphaltenes. 2. Effect of Resins and Additives

    DEFF Research Database (Denmark)

    Khvostichenko, Daria S; Andersen, Simon Ivar

    2010-01-01

    transients recorded during electrodeposition tests indicated that the current was transported by the dissolved asphaltene fraction rather than the solid asphaltene particles and a sharp increase in conductivity was observed upon transition from systems with asphaltene deposition to systems without deposition....

  11. PATH COEFFICIENT ANALYSIS OF SEVERAL COMPONENTS OIL YIELD IN SUNFLOWER (HELIANTHUS ANNUUS L.

    Directory of Open Access Journals (Sweden)

    A. MIjić

    2006-06-01

    Full Text Available The objective of investigation was to analyse oil yield components and their relations by simple coefficient correlations as well as direct and indirect effects to oil yield by path analysis. Twenty-four sunflower hybrids were included in the investigation and their seven traits (plant height, head diameter, 1000 seed weight, hec- tolitar mass, grain yield, oil content and oil yield. Very strong positive correlation was estimated between grain yield and oil yield, strong positive correlation between hectolitar mass and oil yield, and middle corre- lation among oil yield and: 1000 seed weight, plaint height and oil content. There was no correlation between grain yields and oil content. Grain yield showed the strongest effect to oil yield. Oil content had lower effect to oil yield. Other traits showed no significant effect to oil yield, and their effect to oil yield was covered by indirect effect of grain yield.

  12. Determination of asphaltene onset conditions using the cubic plus association equation of state

    DEFF Research Database (Denmark)

    Arya, Alay; von Solms, Nicolas; Kontogeorgis, Georgios M.

    2015-01-01

    The cubic-plus-association (CPA) equation of state (EoS) has already been proven to be a successful model for phase equilibrium calculations for systems containing associating components and has already been applied for asphaltene modeling by few researchers. In the present work, we apply the CPA...

  13. Biomarker distributions in asphaltenes and kerogens analyzed by flash pyrolysis-gas chromatograph-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Van Graas, G.

    1986-01-01

    Biomarker distributions in a suite of asphaltenes and kerogens have been analyzed by flash pyrolysis directly coupled to a GCMS system. Attention has been focussed on biomarkers of the sterane and triterpane types. The sample suite under investigation consists of sediments with different kerogen types and some crude oils. Biomarker distributions in the pyrolysates have been compared with the free biomarkers in the corresponding saturated hydrocarbon fractions. The analyses show significant differences between the distributions of the free biomarkers and those in the pyrolysates. The latter have lower amounts of steranes while diasteranes are absent or present at low concentrations only. In the triterpane traces a shift of maximum intensity from C/sub 30/ (free compounds) to C/sub 27//C/sub 29/ is observed. Furthermore, the pyrolysates contain a set of triterpanes that are present in the saturated hydrocarbon fractions. The observed differences between pyrolysates and free hydrocarbons can be explained partly by the processes occurring during pyrolysis such as bond rupture and subsequent stabilization of primary pyrolysis products. To a certain extent these differences also show that maturation processes occurring in sediments have effects on free biomarker molecules different from those on molecules that are enclosed in a macromolecular matrix (kerogen or asphaltenes). Differences between biomarker distributions of asphaltene and kerogen pyrolysates are relatively small. A comparison with the pyrolysates from extracted whole sediments suggests that these differences are mainly caused by interactions between the organic material and the mineral matrix during pyrolysis. Oil asphaltenes behave differently from sediment asphaltenes as their pyrolysates are more similar to the corresponding saturated hydrocarbon fractions, i.e. the differences described above are observed to a much smaller extent.

  14. Comparative Analysis of Chemical Components of Purified Essential Oil from Nilam Plants using Gas Chromatography

    OpenAIRE

    Emas Agus Prastyo Wibowo; Utami Nofitasari; Atik Setyani; Nuni Widiarti

    2017-01-01

    T This study aimed to determine the chemical components of the patchouli oil. Patchouli oil is one of the export commodities that have high economic value for Indonesia. In general, patchouli oil obtained from the hydrodistillation of patchouli leaves. Most industries are still using patchouli oil refiners made by ferrous metal. The rust will dissolve in patchouli oil obtained and led to the resulting of dark oil and patchouli aroma becomes lower. The main purpose of this research is to ...

  15. Chemical composition of Pechora Sea crude oil

    Directory of Open Access Journals (Sweden)

    Derkach S. R.

    2017-03-01

    Full Text Available The physicochemical properties of the Pechora Sea shelf oil and its chemical composition have been studied using the methods of refractometry, titrimetry, viscometry, rheometry and standard methods for the analysis of oil and petroleum products. The fractionation of oil is held at atmospheric pressure, some fractions boiling at the temperature below and above 211 °C have been received. Chemical structural-group composition of oil and its components has been investigated using a Fourier infrared (IR spectroscopy method. The density of oil has been obtained, it is equal to 24.2 API. The chemical composition analysis shows that water content in the investigated oil sample is about 0.03 % (by weight. The oil sample contains hydrocarbons (including alkanes, naphthenes, arenes and asphaltenes with resins; their content is equal to 89 and 10 % (by weight respectively. Alkane content is about 66 %, including alkanes of normal structure – about 37 %. The solidification temperature of oil sample is equal to –43 °C. This low temperature testifies obliquely low content of solid alkanes (paraffin. Bearing in mind the content of asphaltenes with resins we can refer the investigated oil sample to resinous oils. On the other hand spectral coefficient values (aromaticity quotient and aliphaticity quotient show that oil sample belongs to naphthenic oils. According to the data of Fourier IR spectroscopy contents of naphthenes and arenes are 5.9 and 17.8 % respectively. Thus, the obtained data of chemical structural-group composition of crude oil and its fractions indicate that this oil belongs to the heavy resinous naphthenic oils. The rheological parameters obtained at the shear deformation conditions characterize the crude oil as a visco-plastic medium.

  16. A New Type of Exposed Oil Sand Mine

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    With several means of analysis, the unique organic compound component and distribution of exposed oil sand existing in Qinghai, north-west China, is revealed. Qinghhai oil sand has great content of light components with high saturated hydrocarbon content up to approximately 50%, while its heavy components of colloid and asphaltene is rather low (<38%); straight-chain alkane has a regular distribution concentrating mainly around C28; it has a very high atom ratio of H/C. The physical parameters of the oil sand mine are within the range of common heavy oils. Such chemical composition and distribution obviously differs from that of other known exposed oil sand mines. This particular property of the oil sand is formed due to the unique geographical and geological environment. Therefore, it is intended to exploit the mine with a new combined method, i.e., first drill horizontal wells and then opencut.

  17. Biological marker distribution in coexisting kerogen, bitumen and asphaltenes in Monterey Formation diatomite, California

    Energy Technology Data Exchange (ETDEWEB)

    Tannenbaum, E.; Ruth, E.; Huizinga, B.J.; Kaplan, I.R.

    1986-01-01

    Organic-rich (18.2%) Monterey Formation diatomite from California was studied. The organic matter consist of 94% bitumen and 6% kerogen. Biological markers from the bitumen and from pyrolysates of the coexisting asphaltenes and kerogen were analyzed in order to elucidate the relationship between the various fractions of the organic matter. While 17..cap alpha.. (H), 18..cap alpha.. (H), 21..cap alpha.. (H)-28,30-bisnorhopane was present in the bitumen and in the pyrolysate of the asphaltenes, it was not detected in the pyrolysates of the kerogen. A C/sub 40/-isoprenoid with head to head linkage, however, was present in pyrolysates of both kerogen and asphaltenes, but not in the bitumen from the diatomite. The maturation level of the bitumen, based on the extent of isomerization of steranes and hopanes, was that of a mature oil, whereas the pyrolysate from the kerogen showed a considerably lower maturation level. These relationships indicate that the bitumen may not be indigenous to the diatomite and that it is a mature oil that migrated into the rock. They consider the possibility, however, that some of the 28,30-bisnorhopane-rich Monterey Formation oils have not been generated through thermal degradation of kerogen, but have been expelled from the source rock at an early stage of diagenesis.

  18. Biological marker distribution in coexisting kerogen, bitumen and asphaltenes in Monterey Formation diatomite, California

    Science.gov (United States)

    Tannenbaum, E.; Ruth, E.; Huizinga, B. J.; Kaplan, I. R.

    1986-01-01

    Organic-rich (18.2%) Monterey Formation diatomite from California was studied. The organic matter consist of 94% bitumen and 6% kerogen. Biological markers from the bitumen and from pyrolysates of the coexisting asphaltenes and kerogen were analyzed in order to elucidate the relationship between the various fractions of the organic matter. While 17 alpha(H), 18 alpha(H), 21 alpha(H)-28,30-bisnorhopane was present in the bitumen and in the pryolysate of the asphaltenes, it was not detected in the pyrolysates of the kerogen. A C40-isoprenoid with "head to head" linkage, however, was present in pyrolysates of both kerogen and asphaltenes, but not in the bitumen from the diatomite. The maturation level of the bitumen, based on the extent of isomerization of steranes and hopanes, was that of a mature oil, whereas the pyrolysate from the kerogen showed a considerably lower maturation level. These relationships indicate that the bitumen may not be indigenous to the diatomite and that it is a mature oil that migrated into the rock. We consider the possibility, however, that some of the 28,30-bisnorhopane-rich Monterey Formation oils have not been generated through thermal degradation of kerogen, but have been expelled from the source rock at an early stage of diagenesis.

  19. Biological marker distribution in coexisting kerogen, bitumen and asphaltenes in Monterey Formation diatomite, California

    Science.gov (United States)

    Tannenbaum, E.; Ruth, E.; Huizinga, B. J.; Kaplan, I. R.

    1986-01-01

    Organic-rich (18.2%) Monterey Formation diatomite from California was studied. The organic matter consist of 94% bitumen and 6% kerogen. Biological markers from the bitumen and from pyrolysates of the coexisting asphaltenes and kerogen were analyzed in order to elucidate the relationship between the various fractions of the organic matter. While 17 alpha(H), 18 alpha(H), 21 alpha(H)-28,30-bisnorhopane was present in the bitumen and in the pryolysate of the asphaltenes, it was not detected in the pyrolysates of the kerogen. A C40-isoprenoid with "head to head" linkage, however, was present in pyrolysates of both kerogen and asphaltenes, but not in the bitumen from the diatomite. The maturation level of the bitumen, based on the extent of isomerization of steranes and hopanes, was that of a mature oil, whereas the pyrolysate from the kerogen showed a considerably lower maturation level. These relationships indicate that the bitumen may not be indigenous to the diatomite and that it is a mature oil that migrated into the rock. We consider the possibility, however, that some of the 28,30-bisnorhopane-rich Monterey Formation oils have not been generated through thermal degradation of kerogen, but have been expelled from the source rock at an early stage of diagenesis.

  20. Oil components modulate physical characteristics and function of the natural oil emulsions as drug or gene delivery system.

    Science.gov (United States)

    Chung, H; Kim, T W; Kwon, M; Kwon, I C; Jeong, S Y

    2001-04-28

    Oil-in-water (o/w) type lipid emulsions were formulated by using 18 different natural oils and egg phosphatidylcholine (egg PC) to investigate how emulsion particle size and stability change with different oils. Cottonseed, linseed and evening primrose oils formed emulsions with very large and unstable particles. Squalene, light mineral oil and jojoba bean oil formed stable emulsions with small particles. The remaining natural oils formed moderately stable emulsions. Emulsions with smaller initial particle size were more stable than those with larger particles. The correlation between emulsion size made with different oils and two physical properties of the oils was also investigated. The o/w interfacial tension and particle size of the emulsion were inversely proportional. The effect of viscosity was less pronounced. To study how the oil component in the emulsion modulates the in vitro release characteristics of lipophilic drugs, three different emulsions loaded with two different drugs were prepared. Squalene, soybean oil and linseed oil emulsions represented the most, medium and the least stable systems, respectively. For the lipophilic drugs, release was the slowest from the most stable squalene emulsion, followed by soybean oil and then by linseed oil emulsions. Cationic emulsions were also prepared with the above three different oils as gene carriers. In vitro transfection activity was the highest for the most stable squalene emulsion followed by soybean oil and then by linseed oil emulsions. Even though the in vitro transfection activity of emulsions were lower than the liposome in the absence of serum, the activity of squalene emulsion, for instance, was ca. 30 times higher than that of liposome in the presence of 80% (v/v) serum. In conclusion, the choice of oil component in o/w emulsion is important in formulating emulsion-based drug or gene delivery systems.

  1. Blood transport and genomic effects of olive oil components

    Directory of Open Access Journals (Sweden)

    Muriana, Francisco J.G.

    2004-03-01

    Full Text Available Epidemiological studies suggest that consuming diets rich in (extra virgin olive oil is associated with a low incidence of chronic disease, including cardiovascular disease and cancer. Recent evidence has emerged which implicates raised concentrations of plasma triglycerides in the pathogenesis of coronary artery disease (CAD. It has been demonstrated that olive oil contributes to modulate metabolic processes related to secretion and transport of triglycerides. Intestinal triglyceride-rich lipoproteins from olive oil are very efficiently cleared during postprandial metabolism compared to other oils. Then, there is a massive interaction of nascent and remnant triglyceride-rich lipoproteins, as well as lipid metabolites and fat-soluble components, with hepatic and non-hepatic tissues. A diet-related response involves a multitude of gene products, including proteins implicated in lipid synthesis, oxidation and cell differentiation. Particularly, it has been reported a health beneficial effect of several components from (extra virgin olive oil (fatty acids and minor compounds, which are functioning as regulators of gene transcription . This review reaffirm that a diet rich in extra virgin olive oil is of vital importance in the prevention of cardiovascular and other diseases.Estudios epidemiológicos asocian el consumo de una dieta rica en aceite de oliva (virgen extra con una baja incidencia de enfermedades crónicas, como las enfermedades cardiovasculares y el cáncer. Una concentración elevada de triglicéridos en plasma, tanto en ayunas como durante el metabolismo postprandial, está implicada en la patogénesis cardiovascular. Se ha demostrado que el aceite de oliva contribuye a modular los procesos metabólicos relativos a la secreción y al transporte de triglicéridos. Con respecto a otros aceites comestibles, el aceite de oliva genera lipoproteínas intestinales ricas en triglicéridos que se metabolizan con rapidez. En este contexto, se

  2. Characterization of the rheological behavior of heavy crude oils for the optimization of their transport; Caracterisation du comportement rheologique des bruts lourds en vue de l'optimisation de leur transport

    Energy Technology Data Exchange (ETDEWEB)

    Coustet Pierre, C.

    2003-10-01

    Despite their huge reserves, production of heavy crude oils remains weak, partially because of the high viscosity. This work aims to understand the origin of this viscosity in a view of diminishing In this context, we performed structural (SAXS) and rheological studies (under shearing and oscillatory regime) in order to link macroscopic and microscopic properties of heavy oils. investigated the effect of asphaltenes and resins which are the two most polar and the high molecular mass components of heavy oils. Most of the literature work performed measures organic solvents which are considered as model solvents in a first assumption. These media haw structure too simple compared to oils. That is why we decided to complete this work by experiments in the crude. We shed some light on asphaltenes described as colloidal particles with fractal dimension of 2. Their overlapping, due to numerous polar and hydrogen bonds, responsible for the high viscosity. The contribution of asphaltenes on viscosity is lowered by resins who are able to dissociate aggregates and to reduce the interactions, so to diminish the overlapping The kinetics of formation of bonds involved in asphaltenes overlapping are strongly slower at low temperatures, which implies a shear thinning behavior under sufficiently high shearing. This allow us to describe the crude as a transient network of fractal aggregates. (author)

  3. Far infrared (terahertz) spectroscopy of a series of polycyclic aromatic hydrocarbons and application to structure interpretation of asphaltenes and related compounds.

    Science.gov (United States)

    Cataldo, Franco; Angelini, Giancarlo; García-Hernández, D Aníbal; Manchado, Arturo

    2013-07-01

    A series of 33 different polycyclic aromatic hydrocarbons (PAHs) were studied by far infrared spectroscopy (terahertz spectroscopy) in the spectral range comprised between 600 and 50 cm(-1). In addition to common PAHs like naphthalene, anthracene, phenanthrene, fluoranthene, picene, pyrene, benzo[α]pyrene, and perylene, also quite unusual PAHs were studied like tetracene, pentacene, acenaphtene, acenaphtylene, triphenylene, and decacyclene. A series of alkylated naphthalenes and anthracenes were studied as well as methypyrene. Partially or totally hydrogenated PAHs were also object of the present investigation, ranging from tetrahydronaphthalene (tetralin) to decahydronaphthalene (decalin), 9,10-dihydroanthracene, 9,10-dihydrophenanthrene, hexahydropyrene, and dodecahydrotriphenylene. Finally, the large and quite rare PAHs coronene, quaterrylene, hexabenzocoronene, and dicoronylene were studied by far infrared spectroscopy. The resulting reference spectra were used in the interpretation of the chemical structure of asphaltenes (as extracted from a heavy petroleum fraction and from bitumen), the chemical structures of other petroleum fractions known as DAE (distillate aromatic extract) and RAE (residual aromatic extract), and a possible interpretation of components of the chemical structure of anthracite coal. Asphaltenes, heavy petroleum fractions, and coal were proposed as model compounds for the interpretation of the emission spectra of certain proto-planetary nebulae (PPNe) with a good matching in the mid infrared between the band pattern of the PPNe emission spectra and the spectra of these oil fractions or coal. Although this study was finalized in an astrochemical context, it may find application also in the petroleum and coal chemistry.

  4. Far infrared (terahertz) spectroscopy of a series of polycyclic aromatic hydrocarbons and application to structure interpretation of asphaltenes and related compounds

    Science.gov (United States)

    Cataldo, Franco; Angelini, Giancarlo; García-Hernández, D. A.; Manchado, Arturo

    2013-07-01

    A series of 33 different polycyclic aromatic hydrocarbons (PAHs) were studied by far infrared spectroscopy (terahertz spectroscopy) in the spectral range comprised between 600 and 50 cm-1. In addition to common PAHs like naphthalene, anthracene, phenanthrene, fluoranthene, picene, pyrene, benzo[α]pyrene, and perylene, also quite unusual PAHs were studied like tetracene, pentacene, acenaphtene, acenaphtylene, triphenylene, and decacyclene. A series of alkylated naphthalenes and anthracenes were studied as well as methypyrene. Partially or totally hydrogenated PAHs were also object of the present investigation, ranging from tetrahydronaphthalene (tetralin) to decahydronaphthalene (decalin), 9,10-dihydroanthracene, 9,10-dihydrophenanthrene, hexahydropyrene, and dodecahydrotriphenylene. Finally, the large and quite rare PAHs coronene, quaterrylene, hexabenzocoronene, and dicoronylene were studied by far infrared spectroscopy. The resulting reference spectra were used in the interpretation of the chemical structure of asphaltenes (as extracted from a heavy petroleum fraction and from bitumen), the chemical structures of other petroleum fractions known as DAE (distillate aromatic extract) and RAE (residual aromatic extract), and a possible interpretation of components of the chemical structure of anthracite coal. Asphaltenes, heavy petroleum fractions, and coal were proposed as model compounds for the interpretation of the emission spectra of certain proto-planetary nebulae (PPNe) with a good matching in the mid infrared between the band pattern of the PPNe emission spectra and the spectra of these oil fractions or coal. Although this study was finalized in an astrochemical context, it may find application also in the petroleum and coal chemistry.

  5. Lipid components and oxidative status of selected specialty oils

    Energy Technology Data Exchange (ETDEWEB)

    Madawala, S. R. P.; Kochhar, S. P.; Dutta, P. C.

    2012-11-01

    Many vegetable oils are marketed as specialty oils because of their retained flavors, tastes and distinct characteristics. Specialty oil samples which were commercially produced and retailed were purchased from local superstores in Reading, UK, and Uppsala, Sweden and profiled for detailed lipid composition and oxidative status. These oil samples include: almond, hazelnut, walnut, macadamia nut, argan, avocado, grape seed, roasted sesame, rice bran, cold pressed, organic and cold pressed, warm pressed and refined rapeseed oils. The levels of PV were quite low (0.5-1.3mEq O{sub 2}/kg) but AV and Rancimat values at 100 degree centigrade (except for rapeseed oils) varied considerably at (0.5-15.5) and (4.2-37.0 h) respectively. Macadamia nut oil was found to be the most stable oil followed by argan oil, while walnut oil was the least stable. Among the specialty oils, macadamia nut oil had the lowest (4%) and walnut oil had the highest (71%) level of total PUFA. The organic cold pressed rapeseed oil had considerably lower PUFA (27%) compared with other rapeseed oils (28- 35%). In all the samples, {alpha}- and {gamma}- tocopherols were the major tocopherols; nut oils had generally lower levels. Total sterols ranged from 889 to 15,106 {mu}g/g oil. The major sterols were {beta}-sitosterol (61-85%) and campesterol (6-20%). Argan oil contained schottenol (35%) and spinasterol (32%). Compared with literature values, no marked differences were observed among the differently processed, organically grown or cold pressed rapeseed oils and other specialty oils in this study. (Author) 33 refs.

  6. On the Mass Balance of Asphaltene Precipitation

    DEFF Research Database (Denmark)

    Andersen, Simon Ivar; Lira-Galeana, C.; Stenby, Erling Halfdan

    2001-01-01

    In the evaluation of experimental data as well as in calculation of phase equilibria the necessity of the application of mass balances is obvious. In the case of asphaltenes the colloidal nature of these compounds may highly affect the mass balance. In the present paper several experiments are pe...

  7. Deposition of heavy oil fractions: development of a computational tool to predict oil mixtures compatibility; Deposicao de fracoes pesadas do petroleo: desenvolvimento de uma ferramenta computacional para a previsao da compatibilidade de misturas de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Prucole, Elisia S.; Henriques, Fernanda P.; Silva, Leandro M.; Touma, Silvia L. [PETROBRAS S.A., Rio de de Janeiro, RJ (Brazil)

    2008-07-01

    The remarkable increase in production and processing of national heavy oils is a scenario in which the deposition problem of heavy oil fractions is important, leading to huge losses, not only in economical terms but also in regard to environmental aspects, and can occur in practically all areas of the oil industry. Thus, the knowledge about technology concerning this subject is essential. In terms of heavy fractions, the asphaltenes are the heaviest components of oil and have propensity to aggregate, flocculate, precipitate and be adsorbed on surfaces. The difficulties for modeling the behavior of asphaltenes phases occur because of the high uncertainties which take in the current knowledge about the asphaltenes, their structures, flocculation and precipitation mechanisms and the phenomenon reversibility. The main goal of this work is to propose a predictive methodology for oils compatibility. A fuzzy classifier was implemented in order to predict the compatibility of oil mixtures, assessing whether the mixture condition is stable or not. The results were satisfactory, indicating a good predictive power of the proposed computational tool. (author)

  8. Does antioxidant properties of the main component of essential oil reflect its antioxidant properties? The comparison of antioxidant properties of essential oils and their main components.

    Science.gov (United States)

    Dawidowicz, Andrzej L; Olszowy, Małgorzata

    2014-01-01

    This study discusses the similarities and differences between the antioxidant activities of some essential oils: thyme (Thymus vulgaris), basil (Ocimum basilicum), peppermint (Mentha piperita), clove (Caryophyllus aromaticus), summer savory (Satureja hortensis), sage (Salvia hispanica) and lemon (Citrus limon (L.) Burm.) and of their main components (thymol or estragole or menthol or eugenol or carvacrol or camphor or limonene) estimated by using 2,2'-Diphenyl-1-picrylhydrazyl, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt and β-carotene bleaching assays. The obtained data show that the antioxidant properties of essential oil do not always depend on the antioxidant activity of its main component, and that they can be modulated by their other components. The conclusions concerning the interaction of essential oil components depend on the type of method applied for assessing the antioxidant activity. When comparing the antioxidant properties of essential oils and their main components, the concepts of synergism, antagonism and additivity are very relevant.

  9. Minor components in food oils: a critical review of their roles on lipid oxidation chemistry in bulk oils and emulsions.

    Science.gov (United States)

    Chen, Bingcan; McClements, David Julian; Decker, Eric Andrew

    2011-12-01

    Food oils are primarily composed of triacylglycerols (TAG), but they may also contain a variety of other minor constituents that influence their physical and chemical properties, including diacylglycerols (DAG), monoacylglycerols (MAG), free fatty acids (FFA), phospholipids (PLs), water, and minerals. This article reviews recent research on the impact of these minor components on lipid oxidation in bulk oils and oil-in-water emulsions. In particular, it highlights the origin of these minor components, the influence of oil refining on the type and concentration of minor components present, and potential physicochemical mechanisms by which these minor components impact lipid oxidation in bulk oils and emulsions. This knowledge is crucial for designing food, pharmaceutical, personal care, and other products with improved stability to lipid oxidation.

  10. Investigating New Innovations to Detect Small Salt-Water Fraction Component in Mineral Oil and Small Oil Fraction Component in Salt-Water Projects

    Directory of Open Access Journals (Sweden)

    E.R.R. Mucunguzi-Rugwebe

    2011-09-01

    Full Text Available The main purpose of this study is to present the key findings on the effects of small salt-water fraction component, β expressed in volume % per L on rotation are presented in the temperature range of 19.0 to 24.0ºC. It was found that rotations in oils with low boiling point known as light oils like Final diesel No. 2 were greater than the rotations which occurred in oils with high boiling point called heavy oils such as Esso diesel. Small oil fraction components, γs expressed in mL/L of salt water down to 10 ppm were detected. The greatest impact on rotation of these oils was found in light oils like Fina No. 2 diesel. At 40 ppm which is the oil content level below which the environment authority considers process water to be free from oil environmental hazards, the observed rotation angles were 23.2º for Esso, 36.7º for Nors Hydro AS, and 71.8º in Fina No. 2 diesel. It was observed that light oils molecules have drastic effect on optical properties of the mixture in which they exist. It was found that for all oils, oil fractions greater than 100 ppm, caused the medium to be optically dense. This technology has shown a very high potential of being used as an environmental monitor to detect oil fractions down to 10 ppm and the technique can use laser beam to control re-injected process water with oil fractions between 100-2000 ppm.

  11. Determination of Component Contents of Blend Oil Based on Characteristics Peak Value Integration.

    Science.gov (United States)

    Xu, Jing; Hou, Pei-guo; Wang, Yu-tian; Pan, Zhao

    2016-01-01

    Edible blend oil market is confused at present. It has some problems such as confusing concepts, randomly named, shoddy and especially the fuzzy standard of compositions and ratios in blend oil. The national standard fails to come on time after eight years. The basic reason is the lack of qualitative and quantitative detection of vegetable oils in blend oil. Edible blend oil is mixed by different vegetable oils according to a certain proportion. Its nutrition is rich. Blend oil is eaten frequently in daily life. Different vegetable oil contains a certain components. The mixed vegetable oil can make full use of their nutrients and make the nutrients more balanced in blend oil. It is conducive to people's health. It is an effectively way to monitor blend oil market by the accurate determination of single vegetable oil content in blend oil. The types of blend oil are known, so we only need for accurate determination of its content. Three dimensional fluorescence spectra are used for the contents in blend oil. A new method of data processing is proposed with calculation of characteristics peak value integration in chosen characteristic area based on Quasi-Monte Carlo method, combined with Neural network method to solve nonlinear equations to obtain single vegetable oil content in blend oil. Peanut oil, soybean oil and sunflower oil are used as research object to reconcile into edible blend oil, with single oil regarded whole, not considered each oil's components. Recovery rates of 10 configurations of edible harmonic oil is measured to verify the validity of the method of characteristics peak value integration. An effective method is provided to detect components content of complex mixture in high sensitivity. Accuracy of recovery rats is increased, compared the common method of solution of linear equations used to detect components content of mixture. It can be used in the testing of kinds and content of edible vegetable oil in blend oil for the food quality detection

  12. Monitoring of large diesel engines through asphaltene content

    Energy Technology Data Exchange (ETDEWEB)

    Declerck, R. [Texaco Technology Ghent (Belgium)

    1997-12-31

    Lubricants in large diesel engines, for marine and power plant application, are open contaminated with heavy fuel. This type of contamination results in blackening of the engines and deposit formation because of the coagulation of asphaltene particles. Monitoring of the asphaltene content presents the operator with important information on the condition of the engine and the lubricant. This technique was an important asset in developing a new range of lubricants highly capable of tackling the presence of asphaltenes. (orig.)

  13. Palm oil: a healthful and cost-effective dietary component.

    Science.gov (United States)

    Ong, A S H; Goh, S H

    2002-03-01

    Palm oil is an excellent choice for food manufacturers because of its nutritional benefits and versatility. The oil is highly structured to contain predominantly oleic acid at the sn2-position in the major triacylglycerols to account for the beneficial effects described in numerous nutritional studies. Oil quality and nutritional benefits have been assured for the variety of foods that can be manufactured from the oil directly or from blends with other oils while remaining trans-free. The oxidative stability coupled with the cost-effectiveness is unparalleled among cholesterol-free oils, and these values can be extended to blends of polyunsaturated oils to provide long shelf-life. Presently the supply of genetic-modification-free palm oil is assured at economic prices, since the oil palm is a perennial crop with unparalleled productivity. Numerous studies have confirmed the nutritional value of palm oil as a result of the high monounsaturation at the crucial 2-position of the oil's triacylglycerols, making the oil as healthful as olive oil. It is now recognized that the contribution of dietary fats to blood lipids and cholesterol modulation is a consequence of the digestion, absorption, and metabolism of the fats. Lipolytic hydrolysis of palm oil glycerides containing predominantly oleic acid at the 2 position and palmitic and stearic acids at the 1 and 3 positions allows for the ready absorption of the 2-monoacrylglycerols while the saturated free fatty acids remain poorly absorbed. Dietary palm oil in balanced diets generally reduced blood cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides while raising the high-density lipoprotein (HDL) cholesterol. Improved lipoprotein(a) and apo-A1 levels were also demonstrated from palm oil diets; an important benefits also comes from the lowering of blood triglycerides (or reduced fat storage) as compared with those from polyunsaturated fat diets. Virgin palm oil also provides carotenes apart from

  14. Standoff characterization of high-molecular components of oil disperse systems

    Science.gov (United States)

    Ganeeva, Y. M.; Yusupova, T. N.; Romanov, G. V.; Bashkirtseva, N. Y.; Rafailov, Michael K.

    2012-06-01

    Here we report work done toward standoff characterization of high-molecular components responsible for forming nano-structures in oil disperse system. Complex physical and chemical studies have been conducted specifically on bitumen extracted from rich and poor grade oil sand from Canada. Standoff characterization of oil disperse system highmolecular components is discussed here based on prospective of ultra-fast broadband tunable MWIR laser absorption spectroscopy.

  15. Pyrolysis of asphaltenes from lignite semicoking tar

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Ryl' tsova, S.V.; Rozental, D.A.; Proskuryakov, V.A.; Polovetskaya, O.S.

    2000-07-01

    Pyrolysis of asphaltenes from lignite semicoking tar in the range 750-900{degree}C at a contact time within 0.5-6.0 s was studied. The yields of pyrocarbons, pyrolysis gas, and liquid products and the group composition of the liquid products were determined. The total analysis of the major groups of compounds present in the liquid products was performed, and the optimal conditions of pyrolysis, from the viewpoint of preparation of particular compounds, were recommended.

  16. [Studies of aroma components on essential oil of Chinese kushui rose].

    Science.gov (United States)

    Zhou, Wei; Zhou, Xiao-ping; Zhao, Guo-hong; Liu, Hong-wei; Ding, Lan; Chen, Li-ren

    2002-11-01

    The main chemical components of the rich peculiar aroma in the essential oil of Chinese Kushui rose (R. Setate x R. Rugosa) is reported. The differences in chemical components between Chinese Kushui rose oil and Bulgaria rose oil are compared. By OV1701 capillary column, more than 130 compounds were separated from the essential oil of Chinese Kushui rose. Using GC/MS and GC/IR techniques and some reference standards as the control, 101 compounds were tentatively identified from the separated compounds. This study shows that there are different aromas in rose essential oils. The oil of Chinese Kushui rose would be an important type of rose oil in the world due to its special rose aroma.

  17. Comparative Analysis of Chemical Components of Purified Essential Oil from Nilam Plants using Gas Chromatography

    Directory of Open Access Journals (Sweden)

    Emas Agus Prastyo Wibowo

    2017-01-01

    Full Text Available T This study aimed to determine the chemical components of the patchouli oil. Patchouli oil is one of the export commodities that have high economic value for Indonesia. In general, patchouli oil obtained from the hydrodistillation of patchouli leaves. Most industries are still using patchouli oil refiners made by ferrous metal. The rust will dissolve in patchouli oil obtained and led to the resulting of dark oil and patchouli aroma becomes lower. The main purpose of this research is to improve the quality of patchouli oil by the purification process technologies after oil refining process. In this research the purification of the impure and crude oil can be carried out using adsorption process with bentonite. Purification results with UV-VIS spectrophotometer showed that the activation energy at a wavelength of 510 nm-550 nm with 3.9 x 10-19 Joules. GC (Gas Chromatography analysis showed that there are 13 components from patchouli oil, the 6 dominant peaks were compounds of patchouli alcohol (29.64%, delta-guanine (23.26%, alpha-guanine (21.9%, alpha-patchouline (4.24%, pogostol (4.15%, palustrol (4.00%, beta-pinene (3.9%. Based on the physical properties, the main constituent component content, and the Fe2+ content, refined patchouli oil meets the requirements of the Indonesian National Standards.

  18. The Critical Micelle Concentration of Asphaltenes as Measured by Calorimetry

    DEFF Research Database (Denmark)

    Andersen, Simon Ivar; Christensen, S. D.

    2000-01-01

    Micellization of asphaltenes in solution has been investigated using a micro calorimetric titration procedure (Andersen, S. I.; Birdi, K. S. J Colloid Interface Sci. 1991, 142, 497). The method uses the analysis of heat of dissociation and dilution of asphaltene micelles when a pure solvent (or s...

  19. [Extraction and analysis of chemical components of essential oil in Thymus vulgaris of tissue culture].

    Science.gov (United States)

    Li, Xiao-Dong; Yang, Li; Xu, Shi-Qian; Li, Jian-Guo; Cheng, Zhi-Hui; Dang, Jian-Zhang

    2011-10-01

    To extract the essential oils from the Seedlings, the Aseptic Seedlings and the Tissue Culture Seedlings of Thymus vulgaris and analyze their chemical components and the relative contents. The essential oils were extracted by steam distillation, the chemical components and the relative contents were identified and analyzed by gas chromatography-mass spectrometry (GC/MS) and peak area normalization method. The main chemical components of essential oil in these three samples had no significant difference, they all contained the main components of essential oil in Thymus vulgaris: Thymol, Carvacrol, o-Cymene, gamma-Terpinene, Caryophyllene et al. and only had a slight difference in the relative content. This study provides important theoretical foundation and data reference for further study on production of essential oil in thyme by tissue culture technology.

  20. Static and dynamic superheated water extraction of essential oil components from Thymus vulgaris L.

    Science.gov (United States)

    Dawidowicz, Andrzej L; Rado, Ewelina; Wianowska, Dorota

    2009-09-01

    Superheated water extraction (SWE) performed in both static and dynamic condition (S-SWE and D-SWE, respectively) was applied for the extraction of essential oil from Thymus vulgaris L. The influence of extraction pressure, temperature, time, and flow rate on the total yield of essential oil and the influence of extraction temperature on the extraction of some chosen components are discussed in the paper. The SWE extracts are related to PLE extracts with n-hexane and essential oil obtained by steam distillation. The superheated water extraction in dynamic condition seems to be a feasible option for the extraction of essential oil components from T. vulgaris L.

  1. Essential Oil Component in Flower of Lemon Balm (Melissa officinalis L.

    Directory of Open Access Journals (Sweden)

    Jafer Adinee

    2008-01-01

    Full Text Available This research focuses on the analysis of the chemical composition lemon balm essential oil. The essential oil of flowers was obtained by steam distillation with a Clevenger apparatus. The chemical components of the essential oil of lemon balm were analyzed by capillary GC and GC/MS and 12 substances were identified. The flower oil contained trans-carveol (28.89%, citronellol (25.24%, δ-3-carene (5.26%, citronellal (4.9%, geraniol (2.2%, 1-octene-3-ol (2.03% and spathulenol (2.06%. The trans-carveol in flowers was dominant among components.

  2. Tar balls from Deep Water Horizon oil spill: environmentally persistent free radicals (EPFR) formation during crude weathering.

    Science.gov (United States)

    Kiruri, Lucy W; Dellinger, Barry; Lomnicki, Slawo

    2013-05-07

    Tar balls collected from the Gulf of Mexico shores of Louisiana and Florida after the BP oil spill have shown the presence of electron paramagnetic resonance (EPR) spectra characteristic of organic free radicals as well as transition metal ions, predominantly iron(III) and manganese(II). Two types of organic radicals were distinguished: an asphaltene radical species typically found in crude oil (g = 2.0035) and a new type of radical resulting from the environmental transformations of crude (g = 2.0041-47). Pure asphaltene radicals are resonance stabilized over a polyaromatic structure and are stable in air and unreactive. The new radicals were identified as products of partial oxidation of crude components and result from the interaction of the oxidized aromatics with metal ion centers. These radicals are similar to semiquinone-type, environmentally persistent free radicals (EPFRs) previously observed in combustion-generated particulate and contaminated soils.

  3. Interfacial properties of dissolved crude oil components in produced water

    OpenAIRE

    Eftekhardadkhah, Mona

    2013-01-01

    Produced water is a mixture of water trapped in underground formations and injection water that is brought to the surface along with oil or gas. In general, produced water is a mixture of dispersed oil in water (o/w), dissolved organic compounds (including hydrocarbons), residual concentration of chemical additives from the production line, heavy metals, dissolved minerals and suspended solids.In the year 2011, 131 million m3 of produced water were discharged on the Norwegian Continental Shel...

  4. Crude oil price analysis and forecasting based on variational mode decomposition and independent component analysis

    Science.gov (United States)

    E, Jianwei; Bao, Yanling; Ye, Jimin

    2017-10-01

    As one of the most vital energy resources in the world, crude oil plays a significant role in international economic market. The fluctuation of crude oil price has attracted academic and commercial attention. There exist many methods in forecasting the trend of crude oil price. However, traditional models failed in predicting accurately. Based on this, a hybrid method will be proposed in this paper, which combines variational mode decomposition (VMD), independent component analysis (ICA) and autoregressive integrated moving average (ARIMA), called VMD-ICA-ARIMA. The purpose of this study is to analyze the influence factors of crude oil price and predict the future crude oil price. Major steps can be concluded as follows: Firstly, applying the VMD model on the original signal (crude oil price), the modes function can be decomposed adaptively. Secondly, independent components are separated by the ICA, and how the independent components affect the crude oil price is analyzed. Finally, forecasting the price of crude oil price by the ARIMA model, the forecasting trend demonstrates that crude oil price declines periodically. Comparing with benchmark ARIMA and EEMD-ICA-ARIMA, VMD-ICA-ARIMA can forecast the crude oil price more accurately.

  5. Chemistry, antioxidant, antibacterial and antifungal activities of volatile oils and their components.

    Science.gov (United States)

    De Martino, Laura; De Feo, Vincenzo; Fratianni, Florinda; Nazzaro, Filomena

    2009-12-01

    The present paper reports the chemical composition, antioxidant and antibacterial activities of several essential oils and their components. Analysis showed that three oils (Carum carvi L., Verbena officinalis L. and Majorana hortensis L.) contained predominantly oxygenated monoterpenes, while others studied (Pimpinella anisum L., Foeniculum vulgare Mill.) mainly contained anethole. C. carvi, V. officinalis and M. hortensis oils exhibited the most potent antioxidant activity, due their contents of carvacrol, anethole and estragol. Antibacterial action was assessed against a range of pathogenic and useful bacteria and fungi of agro-food interest. V. officinalis and C. carvi oils proved the most effective, in particular against Bacillus cereus and Pseudomonas aeruginosa. Carvacrol proved most active against Escherichia coli, and completely inhibited the growth of Penicillium citrinum. The oils proved inactive towards some Lactobacilli strains, whereas single components showed an appreciable activity. These results may be important for use of the essential oils as natural preservatives for food products.

  6. Inhibitory effects of citrus essential oils and their components on the formation of N-nitrosodimethylamine.

    Science.gov (United States)

    Sawamura, M; Sun, S H; Ozaki, K; Ishikawa, J; Ukeda, H

    1999-12-01

    Twenty-eight kinds of citrus essential oils and their components were studied for inhibitory effects on the formation of N-nitrosodimethylamine (NDMA). The reaction mixture consisted of dimethylamine and sodium nitrite adjusted at pH 3.6, in addition to essential oils and an emulsifying agent. The quantification was determined by high-performance liquid chromatography monitored at 220 nm. All of the essential oils inhibited the formation of NDMA in the range of 20-85%. The oils of ujukitsu (Citrus ujukitsu Hort. ex Shirai), yuzu (C. junos Tanaka), mochiyu (C. inflata Hort. ex Tanaka), and ponkan (C. reticulata Blanco cv. F-2426) inhibited the formation of NDMA much more effectively than other citrus oils. The inhibitory proportions of components of citrus essential oils such as myrcene, alpha-terpinene, and terpinolene were as high as 80%.

  7. [Anti-Candida albicans activity of essential oils including Lemongrass (Cymbopogon citratus) oil and its component, citral].

    Science.gov (United States)

    Abe, Shigeru; Sato, Yuichi; Inoue, Shigeharu; Ishibashi, Hiroko; Maruyama, Naho; Takizawa, Toshio; Oshima, Haruyuki; Yamaguchi, Hideyo

    2003-01-01

    The effects of 12 essential oils, popularly used as antifungal treatments in aromatherapy, on growth of Candida albicans were investigated. Mycelial growth of C. albicans, which is known to give the fungus the capacity to invade mucosal tissues, was inhibited in the medium containing 100 micro g/ml of the oils: lemongrass (Cymbopogon citratus), thyme (Thymus vulgaris), patchouli (Pogostemon cablin) and cedarwood (Cedrus atlantica). Not only lemongrass oil but also citral, a major component of lemongrass oil (80%), in the range of 25 and 200 micro g/ml inhibited the mycelial growth but allowed yeast-form growth. More than 200 micro g/ml of citral clearly inhibited both mycelial and yeast-form growth of C. albicans. These results provide experimental evidence suggesting the potential value of lemongrass oil for the treatment of oral or vaginal candidiasis.

  8. Influence sur les imbrûlés solides de composés métalliques particuliers et du taux de dispersion des asphaltènes dans les fuels lourds Influence of Unburned Solids Made of Unusual Metal Compounds and of the Asphaltene Dispersion Rate in Heavy Fuel Oils

    Directory of Open Access Journals (Sweden)

    Audibert F.

    2006-11-01

    des asphaltes précipités au pentane dilués avec un gaz oil aromatique de raffinerie. Il a été notamment mis en évidence le rôle joué par les résines dans les dispersions des agglomérats d'asphaltènes et par voie de conséquence dans l'émission d'imbrûlés solides. L'ensemble des observations faites permet de mieux comprendre certains mécanismes intervenant en combustion de fuels lourds. Si l'on se situe sur le plan des émissions particulaires, celles-ci peuvent être largement réduites par l'utilisation de taux suffisants de vapeur auxiliaire au niveau de l'injection. The growing diversity of the origins of crude oils has led to giving consideration to the metal content in combustion models in addition of Conradson carbon or C7 asphaltenes in heavy fuel oils. Such models have been developed by Exxon (1979 and Shell (1981 in particular. Recent research done at Institut Français du Pétrole (IFP on a 2 MW package boiler has shown the influence of unusual metal compounds present in fuel oil in the form of sulfides impregnating porous carbon particles. These microparticles may be formed when severe operating conditions are applied to the visbreaking of residual fuel oils in the presence of hydrogen and a suitable catalyst. These microparticles have proved to be very active in combustion and have shown that the metal concentration is not the only factor to be taken into consideration but that the way in which it is combined may be preponderant. To widen the field of application of models, other parameters, such as the operating conditions of the boiler and the spraying of the fuel oil, have been taken into consideration together with the actual parameters of the influence of the fuel oil (research by the MIT Energy Laboratory, publications in 1986. Concerning the predicting of particulate emissions, a method in addition to tests for Conradson residue and n-heptane insolubility has been applied at IFP as part of a project to upgrade heavy oils in

  9. Lipid components and oxidative status of selected specialty oils

    Directory of Open Access Journals (Sweden)

    P. Madawala, S. R.

    2012-06-01

    Full Text Available Many vegetable oils are marketed as specialty oils because of their retained flavors, tastes and distinct characteristics. Specialty oil samples which were commercially produced and retailed were purchased from local superstores in Reading, UK, and Uppsala, Sweden and profiled for detailed lipid composition and oxidative status. These oil samples include: almond, hazelnut, walnut, macadamia nut, argan, avocado, grape seed, roasted sesame, rice bran, cold pressed, organic and cold pressed, warm pressed and refined rapeseed oils. The levels of PV were quite low (0.5-1.3mEq O₂/kg but AV and Rancimat values at 100 °C (except for rapeseed oils varied considerably at (0.5-15.5 and (4.2-37.0 h respectively. Macadamia nut oil was found to be the most stable oil followed by argan oil, while walnut oil was the least stable. Among the specialty oils, macadamia nut oil had the lowest (4% and walnut oil had the highest (71% level of total PUFA. The organic cold pressed rapeseed oil had considerably lower PUFA (27% compared with other rapeseed oils (28- 35%. In all the samples, α- and γ- tocopherols were the major tocopherols; nut oils had generally lower levels. Total sterols ranged from 889 to 15,106 μg/g oil. The major sterols were β-sitosterol (61-85% and campesterol (6-20%. Argan oil contained schottenol (35% and spinasterol (32%. Compared with literature values, no marked differences were observed among the differently processed, organically grown or cold pressed rapeseed oils and other specialty oils in this study.

    Muchos aceites vegetales se venden como aceites especiales debido a su flavor, gusto y características distintas. Muestras de aceites especiales de almendra, avellana, nuez, nuez de macadamia, argán, aguacate, semillas de uva, de sésamo tostadas, salvado de arroz, y aceites orgánico de semillas de colza prensado en frío y, prensado caliente, y refinados que se producen y comercializan al por menor, se obtuvieron en

  10. Diallel Anaysis of Oil Production Components in Peanut (Arachis hypogaea L.

    Directory of Open Access Journals (Sweden)

    Jeffrey N. Wilson

    2013-01-01

    Full Text Available Peanut (Arachis hypogaea L. has the potential to become a major source of biodiesel, but for market viability, peanut oil yields must increase. Oil yield in peanut is influenced by many different components, including oil concentration, seed mass, and mean oil produced per seed. All of these traits can potentially be improved through selection as long as there is sufficient genetic variation. To assess the variation for these traits, a diallel mating design was used to estimate general combining ability, specific combining ability, and heritability. General combining ability estimates were significant for oil concentration, weight of 50 sound mature kernels (50 SMK, and mean milligrams oil produced per SMK (OPS. Specific combining ability was significant for oil concentration. Reciprocal effects were detected for OPS. Narrow-sense heritability estimates were very high for oil concentration and 50 SMK and low for OPS. The low OPS heritability estimate was caused by the negative correlation between oil concentration and seed size. Consequently, oil concentration and seed mass alone can be improved through early generation selection, but large segregating populations from high oil crosses will be needed to identify progeny with elevated oil concentrations that maintain acceptable seed sizes.

  11. Avaliação geoquímica de biomarcadores ocluídos em estruturas asfaltênicas Geochemical evaluation of occluded biomarkers in asphaltenic structures

    Directory of Open Access Journals (Sweden)

    Débora de Almeida Azevedo

    2009-01-01

    Full Text Available Asphaltenes from two Brazilian crude oils were submitted to mild oxidation to disrupt their structure, releasing the occluded oil. The released hydrocarbons were compared with those from the original crude oil, and used to evaluate the alteration of the oils, especially as a result of biodegradation, but also thermal maturity. The crude oils used are depleted in n-alkanes, which are usually related to biodegradation. However, the released products from the corresponding asphaltenes have n-alkane distributions from nC10 to nC40, suggesting a protection effect from biodegradation. The m/z 191 mass chromatograms showed higher relative intensities for tricyclic terpanes than the hopanes in the crude in comparison with the released ones.

  12. Effect of (+)-pulegone and other oil components of Mentha x piperita on cucumber respiration

    NARCIS (Netherlands)

    Mucciarelli, M.; Camusso, W.; Bertea, C.M.; Bossi, S.; Maffei, M.

    2001-01-01

    Peppermint (Menthaxpiperita L.) essential oil and main components were assessed for their ability to interfere with plant respiratory functions. Tests were conducted on both root segments and mitochondria isolated by etiolated seedlings of cucumber (Cucumis sativus L.). Total essential oil inhibited

  13. Effect of (+)-pulegone and other oil components of Mentha x piperita on cucumber respiration

    NARCIS (Netherlands)

    Mucciarelli, M.; Camusso, W.; Bertea, C.M.; Bossi, S.; Maffei, M.

    2001-01-01

    Peppermint (Menthaxpiperita L.) essential oil and main components were assessed for their ability to interfere with plant respiratory functions. Tests were conducted on both root segments and mitochondria isolated by etiolated seedlings of cucumber (Cucumis sativus L.). Total essential oil inhibited

  14. Abundance quantification by independent component analysis of hyperspectral imagery for oil spill coverage calculation

    Science.gov (United States)

    Han, Zhongzhi; Wan, Jianhua; Zhang, Jie; Zhang, Hande

    2016-08-01

    The estimation of oil spill coverage is an important part of monitoring of oil spills at sea. The spatial resolution of images collected by airborne hyper-spectral remote sensing limits both the detection of oil spills and the accuracy of estimates of their size. We consider at-sea oil spills with zonal distribution in this paper and improve the traditional independent component analysis algorithm. For each independent component we added two constraint conditions: non-negativity and constant sum. We use priority weighting by higher-order statistics, and then the spectral angle match method to overcome the order nondeterminacy. By these steps, endmembers can be extracted and abundance quantified simultaneously. To examine the coverage of a real oil spill and correct our estimate, a simulation experiment and a real experiment were designed using the algorithm described above. The result indicated that, for the simulation data, the abundance estimation error is 2.52% and minimum root mean square error of the reconstructed image is 0.030 6. We estimated the oil spill rate and area based on eight hyper-spectral remote sensing images collected by an airborne survey of Shandong Changdao in 2011. The total oil spill area was 0.224 km2, and the oil spill rate was 22.89%. The method we demonstrate in this paper can be used for the automatic monitoring of oil spill coverage rates. It also allows the accurate estimation of the oil spill area.

  15. COMPATIBILITY STUDIES ON POLYMER/WAX AND POLYMER/RESIN-ASPHALTENE BY VISCOMETRY AND PHOTOMICROGRAPHY

    Institute of Scientific and Technical Information of China (English)

    QIAN Jinwen; QI Guorong; DING Xinzhe; YANG Shiling

    1997-01-01

    The compatibility of mixtures of polymeric pour point depressants, i.e. poly(ethylene-co-vinylacetate) (EVA), poly(EVA-graft-octadecylacrylate) (EVA-g-POA), poly(ethylene-co-octadecylacrylate) (EOA) and poly(ethylene oxide-co-propylene oxide) (EO-co-PO) with wax or resin-asphaltene from crude oil have been studied by means of dilute-solution viscometry. It was found that each mixture pair is incompatible, but the degrees of incompatibility are quite different, which are in good agreement with the results from photomicrography.

  16. The identification of major component of temu kunci (Kaemferia pandurata Roxb.) essential oils on different altitude

    OpenAIRE

    RETNA BANDRIATI ARNIPUTRI; AMALIA TETRANI SAKYA; MUJI RAHAYU

    2007-01-01

    The aims of this study was to know the major component of essential oils of Temu Kunci (Kaemferia pandurata Roxb.) on a different altitude. This research was carried out by method of Stahl destilation at BPTO and GCMS Cromatography at FMIPA UGM for both of from Kerjo (350 m asl) and Jumapolo (450 m asl). The difference of altitude of temu kunci’s lives on, the same of major component of essential oil but the content among them was different.

  17. A theory of phase separation in asphaltene-micellar solutions

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco Sanchez, Juan H. [Instituto Mexicano del Petroleo, Mexico D.F. (Mexico)

    2001-08-01

    A theory of phase separation in micellar solutions of asphaltene in aromatic hydrocarbons was reported in this paper, based on both the approach of the phase behavior of amphiphile/water micelles, and the self-association of asphaltene in aromatic core. Several experimental techniques have been used by different investigators showing the existence of some kind of critical micellar concentration (CMC) on asphaltenes in aromatic solutions. So, at least asphaltene-monomer and asphaltene-micellar phases are experimentally demonstrated facts. These two phases are the main purpose in this report on a theoretical model. Some results show the temperature versus asphaltene concentration phase diagram. The phase diagram is examined against the limited critical micelle concentration data for asphaltenes-in-toluene systems. Such phase diagram is also qualitatively examined against an experimental demonstration of phase separation. The asphaltene-micelle growth depends on the parameter K responsible for the shape and size of it. At the same time, parameter K depends on both the number of asphaltene-monomer associated in the asphaltene-micelle, and the chemical potentials in the interior and in the periphery of the micelle. An expression for getting the number of asphaltene-monomers self-associated in the asphaltene-micelle was obtained. [Spanish] Se reporta una teoria de separacion de fases en soluciones micelares de asfalteno en hidrocarburos aromaticos, basada tanto en la conducta de fase de micelas formadas por anififilos en agua como en la autoasociacion de asfaltenos en nucleos aromaticos. Se han usado diversas tecnicas experimentales por diferentes investigadores que demuestran la existancia de algun tipo de concentracion micelar critica (CMC) de soluciones de asfaltenos en aromaticos. Entonces, al menos las fases de asfalteno-monomerico y de asfalteno-micelar son hechos experimentalmente demostrados. Esta dos fases son el principal proposito de este reporte en un modelo

  18. HPLC-UV Polyphenolic Profiles in the Classification of Olive Oils and Other Vegetable Oils via Principal Component Analysis

    Directory of Open Access Journals (Sweden)

    Mireia Farrés-Cebrián

    2016-12-01

    Full Text Available High performance liquid chromatography-ultraviolet (HPLC-UV was applied to the analysis and characterization of olive oils and other vegetable oils. A chromatographic separation on a Zorbax Eclipse XDB-C8 reversed-phase column was proposed under gradient elution, employing 0.1% formic acid aqueous solution and methanol as mobile phase, for the determination of 14 polyphenols and phenolic acids, allowing us to obtain compositional profiles in less than 20 min. Acceptable sensitivity (limit of detection (LOD values down to 80 µg/L in the best of cases, linearity (r2 higher than 0.986, good run-to-run and day-to-day precisions (relative standard deviation (RSD values lower than 11.5%, and method trueness (relative errors lower than 6.8% were obtained. The proposed HPLC-UV method was then applied to the analysis of 72 oil samples (47 olive oils and 27 vegetable oils including sunflower, soy, corn, and mixtures of them. Analytes were recovered using a liquid–liquid extraction method employing ethanol:water 70:30 (v/v solution and hexane as extracting and defatting solvents, respectively. HPLC-UV polyphenolic profiles using peak areas were then analysed by principal component analysis (PCA to extract information from the most significant data contributing to the characterization and classification of olive oils against other vegetable oils, as well as among Arbequina and Picual olive oil varieties. PCA results showed a noticeable difference between olive oils and the other classes. In addition, a reasonable discrimination of olive oils as a function of fruit varieties was also encountered.

  19. [Supercritical CO2 extraction and component analysis of Aesculus wilsonii seed oil].

    Science.gov (United States)

    Chen, Guang-Yu; Shi, Zhao-Hua; Li, Hai-Chi; Ge, Fa-Huan; Zhan, Hua-Shu

    2013-03-01

    To research the optimal extraction process of supercritical CO2 extraction and analyze the component of the oil extracted from Aesculus wilsonii seed. Using the yield of Aesculus wilsonii seed oil as the index, optimized supercritical CO2 extraction parameter by orthogonal experiment methodology and analysed the compounds of Aesculus wilsonii seed oil by GC-MS. The optimal parameters of the supercritical CO2 extraction of the oil extracted from Aesculus wilsoniit seed were determined: the extraction pressure was 28 MPa and the temperature was 38 degrees C, the separation I pressure was 12 MPa and the temperature was 40 degrees C, the separation II pressure was 5 MPa and the temperature was 40 degrees C, the extraction time was 110 min. The average extraction rate of Aesculus wilsonii seed oil was 1.264%. 26 kinds of compounds were identified by GC-MS in Aesculus wilsonii seed oil extracted by supercritical CO2. The main components were fatty acids. Comparing with the petroleum ether extraction, the supercritical CO2 extraction has higher extraction rate, shorter extraction time, more clarity oil. The kinds of fatty acids with high amounts in Aesculus wilsonii seed oil is identical in general, the kinds of fatty acids with low amounts in Aesculus wilsonii seed oil have differences.

  20. Authenticity analysis of citrus essential oils by HPLC-UV-MS on oxygenated heterocyclic components

    Directory of Open Access Journals (Sweden)

    Hao Fan

    2015-03-01

    Full Text Available Citrus essential oils are widely applied in food industry as the backbone of citrus flavors. Unfortunately, due to relatively simple chemical composition and tremendous price differences among citrus species, adulteration has been plaguing the industry since its inception. Skilled blenders are capable of making blends that are almost indistinguishable from authentic oils through conventional gas chromatography analysis. A reversed-phase high performance liquid chromatography (HPLC method was developed for compositional study of nonvolatile constituents in essential oils from major citrus species. The nonvolatile oxygenated heterocyclic components identified in citrus oils were proved to be more effective as markers in adulteration detection than the volatile components. Authors are hoping such an analysis procedure can be served as a routine quality control test for authenticity evaluation in citrus essential oils.

  1. Effects of oil dispersants on settling of marine sediment particles and particle-facilitated distribution and transport of oil components.

    Science.gov (United States)

    Cai, Zhengqing; Fu, Jie; Liu, Wen; Fu, Kunming; O'Reilly, S E; Zhao, Dongye

    2017-01-15

    This work investigated effects of three model oil dispersants (Corexit EC9527A, Corexit EC9500A and SPC1000) on settling of fine sediment particles and particle-facilitated distribution and transport of oil components in sediment-seawater systems. All three dispersants enhanced settling of sediment particles. The nonionic surfactants (Tween 80 and Tween 85) play key roles in promoting particle aggregation. Yet, the effects varied with environmental factors (pH, salinity, DOM, and temperature). Strongest dispersant effect was observed at neutral or alkaline pH and in salinity range of 0-3.5wt%. The presence of water accommodated oil and dispersed oil accelerated settling of the particles. Total petroleum hydrocarbons in the sediment phase were increased from 6.9% to 90.1% in the presence of Corexit EC9527A, and from 11.4% to 86.7% for PAHs. The information is useful for understanding roles of oil dispersants in formation of oil-sediment aggregates and in sediment-facilitated transport of oil and PAHs in marine eco-systems.

  2. Minor components in oils obtained from Amazonian palm fruits

    Directory of Open Access Journals (Sweden)

    Santos, M. F.G.

    2013-12-01

    Full Text Available This study deals with the characterization of minor compounds in oils obtained from the mesocarp of fruits of the main palm species from the State of Amapá, Brazil, i.e. bacaba (Oenocarpus bacaba, buriti (Mauritia flexuosa, inajá (Maximiliana maripa, pupunha (Bactris gasipaes and tucumã (Astrocaryum vulgare. The concentration of minor glyceridic compounds, i.e. dimeric triacylglycerols (TAG, the oxidized TAG and diacylglycerols (DAG related to oil quality, and the compounds of unsaponifiable matter, i.e. hydrocarbons, aliphatic alcohols, sterols and tocopherols have been determined. The results indicate that the extracted oils had good initial quality, with DAG as the major glyceridic compound. The contents of hydrocarbons (50-734 mg·kg–1 and aliphatic alcohols (80-490 mg·kg–1 were highly variable with inajá oil containing the highest contents. In the case of tocopherols, buriti (1567 mg·kg–1 and tucumã (483 mg·kg–1 oils had the highest contents and the presence of significant amounts of tocotrienols was only detected in inajá oil. Finally, high concentrations of sterols were found in all the samples, particularly in the oils from pupunha (4456 mg·kg–1 and tucumã (2708 mg·kg–1, with β-sitosterol being the major sterol in all the samples with percentages between 65 and 83%.El objetivo de este estudio fue la caracterización de los componentes menores presentes en los aceites obtenidos del mesocarpio de frutos de especies de bacaba (Oenocarpus bacaba, buriti (Mauritia flexuosa, inajá (Maximiliana maripa, pupuña (Bactris gasipaes y tucumá (Astrocaryum vulgare, de importante producción en el Estado de Amapá, Brasil. Se determinaron las dos principales fracciones presentes en los aceites. Por una parte, los compuestos menores derivados de los componentes mayoritarios o triglicéridos (TAG: dímeros de TAG, TAG oxidados y diglicéridos (DAG relacionados con la calidad de los aceites y, por otra, los principales grupos

  3. [Supercritical CO2 fluid extraction and component analysis of leaves oil from Taxus chinensis var. mairei].

    Science.gov (United States)

    Tang, Bin; Zhang, Feng-su; Li, Xiang; Chen, Jian-wei; Yao, Xiao

    2013-12-01

    To research the optimal extraction process of supercritical CO2 extraction and analyze the component of the oil extracted from leaves of Taxus chinensis var. mairei. Using the yield of leaves oil from Taxus chinensis var. mairei as the index, investigated the effect of the extraction pressure, extraction temperature and extraction time on the extracting-rate of leaves oil. The chemical composition of the extracted leaves oil was analyzed by derivatized GC-MS. The optimal parameters of the supercritical CO2 extraction of the oil extracted from leaves of Taxus chinensis var. mairei were determined: CO2 compressor pump frequency was 10 Hz, the extraction pressure was 25 MPa and the temperature of extraction was 45 degrees C, the extraction time was 120 min, the isolator I pressure was 8.0 MPa and the temperature of extraction was 40 degrees C, the isolator II pressure was 5.0 MPa and the temperature of extraction was 35 degrees C. The extracted leaves oil was derivatized with boron trifluoride-methanol complex. Thirty-three kinds of fatty acids were identified by GC-MS. The yield of leaves oils are different from Taxus chinensis var. mairei from 3 habitats. The yield of leaves oil from Donggang, Wuxi city is the highest, about 2.61%. The kinds of fatty acids with high amounts in leaves oil from Taxus chinensis var. mairei is identical in general, the kinds of fatty acids with low amounts in leaves oil from Taxus chinensis var. mairei have differences.

  4. Nanoscale characteristics of triacylglycerol oils: phase separation and binding energies of two-component oils to crystalline nanoplatelets.

    Science.gov (United States)

    MacDougall, Colin J; Razul, M Shajahan; Papp-Szabo, Erzsebet; Peyronel, Fernanda; Hanna, Charles B; Marangoni, Alejandro G; Pink, David A

    2012-01-01

    Fats are elastoplastic materials with a defined yield stress and flow behavior and the plasticity of a fat is central to its functionality. This plasticity is given by a complex tribological interplay between a crystalline phase structured as crystalline nanoplatelets (CNPs) and nanoplatelet aggregates and the liquid oil phase. Oil can be trapped within microscopic pores within the fat crystal network by capillary action, but it is believed that a significant amount of oil can be trapped by adsorption onto crystalline surfaces. This, however, remains to be proven. Further, the structural basis for the solid-liquid interaction remains a mystery. In this work, we demonstrate that the triglyceride liquid structure plays a key role in oil binding and that this binding could potentially be modulated by judicious engineering of liquid triglyceride structure. The enhancement of oil binding is central to many current developments in this area since an improvement in the health characteristics of fat and fat-structured food products entails a reduction in the amount of crystalline triacylglycerols (TAGs) and a relative increase in the amount of liquid TAGs. Excessive amounts of unbound, free oil, will lead to losses in functionality of this important food component. Engineering fats for enhanced oil binding capacity is thus central to the design of more healthy food products. To begin to address this, we modelled the interaction of triacylglycerol oils, triolein (OOO), 1,2-olein elaidin (OOE) and 1,2-elaidin olein (EEO) with a model crystalline nanoplatelet composed of tristearin in an undefined polymorphic form. The surface of the CNP in contact with the oil was assumed to be planar. We considered pure OOO and mixtures of OOO + OOE and OOO + EEO with 80% OOO. The last two cases were taken as approximations to high oleic sunflower oil (HOSO). The intent was to investigate whether phase separation on a nanoscale took place. We defined an "oil binding capacity" parameter, B

  5. The distribution of polycyclic aromatic hydrocarbons in asphaltenes

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Morales, Y. [Inst. Mexicano del Petroleo, Lazaro (Mexico). Programa de Ingenieria Molecular; Ballard Andrews, A.; Mullins, O.C. [Schlumberger-Doll Research Center, Cambridge, MA (United States)

    2008-07-01

    The distribution of polycyclic aromatic hydrocarbons (PAHs) in asphaltenes is a strong determinant for asphaltene physical properties. PAHs also provide the UV and visible absorption and emission profiles of asphaltenes. All PAHs absorb light in the UV-visible spectrum and many also emit light in this spectral range. This study combined a molecular orbital theory with an experimental approach to quantitatively link the UV-visible absorption and emission profiles to the asphaltene PAH distribution. Key features of the absorption and emission spectral data were found to be reproduced with PAH distributions centered at 7 fused rings. The study also identified other highly different distributions of PAHs in terms of plausibility to account for the measured optical data. The paper also described the affect that heteroatoms had on the analysis.

  6. Component Cost of Fuel Oil of Waste Transportation Cost

    Directory of Open Access Journals (Sweden)

    Burhamtoro

    2013-10-01

    Full Text Available The success of the transportation system can be measured based on four things, namely the efficiency of time, energy and fuel efficiency, environmental impact, and safety. Efficiency of energy and fuel is often stated as part of vehicle operating costs (VOC. So need to know the amount of the percentage of the fuel cost component of vehicle operating costs. The purpose of this study was to determine the percentage of the fuel cost component of the total cost of transportation. Research object is a dump truck or on the SCS transport system that serves the city of Malang. Stages of research begins with getting the data needed to analyze the cost of transporting waste. Furthermore, the analysis performed to determine the percentage of each component of transport costs. Results of the analysis showed that the greatest percentage of the cost of each component of the cost of transporting waste is a component of the fuel, while the smallest percentage of the cost of the mechanical components. For the percentage of fuel costs by 28.90% of the variable cost per kilometer, while the percentage of fuel costs by 27.45% of the total cost of transporting waste on his m3each.

  7. Chemical composition and antiprotozoal activities of Colombian Lippia spp essential oils and their major components

    Directory of Open Access Journals (Sweden)

    Patricia Escobar

    2010-03-01

    Full Text Available The chemical composition and biological activities of 19 essential oils and seven of their major components were tested against free and intracellular forms of Leishmania chagasi and Trypanosoma cruzi parasites as well as Vero and THP-1 mammalian cell lines. The essential oils were obtained from different species of Lippia, a widely distributed genus of Colombian plants. They were extracted by microwave radiation-assisted hydro-distillation and characterised by GC-FID and GC-MS. The major components were geranial, neral, limonene, nerol, carvacrol, p-cymene, γ-terpinene, carvone and thymol. The essential oil of Lippia alba exhibited the highest activity against T. cruzi epimastigotes and intracellular amastigotes with an IC50 of 5.5 μg/mL and 12.2 μg/mL, respectively. The essential oil of Lippia origanoides had an IC50 of 4.4 μg/mL in L. chagasi promastigotes and exhibited no toxicity in mammalian cells. Thymol (IC50 3.2 ± 0.4 μg/mL and S-carvone (IC50 6.1 ± 2.2 μg/mL, two of the major components of the active essential oils, were active on intracellular amastigotes of T. cruziinfected Vero cells, with a selective index greater than 10. None of the essential oils or major components tested in this study was active on amastigotes of L. chagasi infected THP-1 cells.

  8. Chemical composition and antiprotozoal activities of Colombian Lippia spp essential oils and their major components.

    Science.gov (United States)

    Escobar, Patricia; Milena Leal, Sandra; Herrera, Laura Viviana; Martinez, Jairo Rene; Stashenko, Elena

    2010-03-01

    The chemical composition and biological activities of 19 essential oils and seven of their major components were tested against free and intracellular forms of Leishmania chagasi and Trypanosoma cruzi parasites as well as Vero and THP-1 mammalian cell lines. The essential oils were obtained from different species of Lippia, a widely distributed genus of Colombian plants. They were extracted by microwave radiation-assisted hydro-distillation and characterised by GC-FID and GC-MS. The major components were geranial, neral, limonene, nerol, carvacrol, p-cymene, gamma-terpinene, carvone and thymol. The essential oil of Lippia alba exhibited the highest activity against T. cruzi epimastigotes and intracellular amastigotes with an IC50 of 5.5 microg/mL and 12.2 microg/mL, respectively. The essential oil of Lippia origanoides had an IC50 of 4.4 microg/mL in L. chagasi promastigotes and exhibited no toxicity in mammalian cells. Thymol (IC50 3.2 +/- 0.4 microg/mL) and S-carvone (IC50 6.1 +/- 2.2 microg/mL), two of the major components of the active essential oils, were active on intracellular amastigotes of T. cruziinfected Vero cells, with a selective index greater than 10. None of the essential oils or major components tested in this study was active on amastigotes of L. chagasi infected THP-1 cells.

  9. HINDERED DIFFUSION OF ASPHALTENES AT ELEVATED TEMPERATURE AND PRESSURE

    Energy Technology Data Exchange (ETDEWEB)

    James A. Guin; Ganesh Ramakrishnan

    1999-10-07

    During this time period, experiments were performed to study the diffusion controlled uptake of quinoline and a coal asphaltene into porous carbon catalyst pellets. Cyclohexane and toluene were used as solvents for quinoline and the coal asphaltene respectively. The experiments were performed at 27 C and 75 C, at a pressure of 250 psi (inert gas) for the quinoline/cyclohexane system. For the coal asphaltene/toluene system, experiments were performed at 27 C, also at a pressure of 250 psi. These experiments were performed in a 20 cm{sup 3} microautoclave, the use of which is advantageous since it is economical from both a chemical procurement and waste disposal standpoint due to the small quantities of solvents and catalysts used. A C++ program was written to simulate data using a mathematical model which incorporated both diffusional and adsorption mechanisms. The simulation results showed that the mathematical model satisfactorily fitted the adsorptive diffusion of quinoline and the coal asphaltene onto a porous activated carbon. For the quinoline/cyclohexane system, the adsorption constant decreased with an increase in temperature. The adsorption constant for the coal asphaltene/toluene system at 27 C was found to be much higher than that of the quinoline/cyclohexane system at the same temperature. Apparently the coal asphaltenes have a much greater affinity for the surface of the carbon catalyst than is evidenced by the quinoline molecule.

  10. Major components in oils obtained from Amazonian palm fruits

    Directory of Open Access Journals (Sweden)

    Santos, M. F. G.

    2013-06-01

    Full Text Available Native palm trees belong to the Arecaceae family and are among the most useful plant resources in the Amazons. Despite its great diversity and various uses, few species have been study in detail, which makes it necessary to perform more comprehensive studies on the quality and composition of species not yet explored. This study deals with the characterization of the major compounds in the oils obtained from the mesocarp of fruits of the main palm species from the State of Amapá, Brasil, i.e. bacaba (Oenocarpus bacaba, buriti (Mauritia flexuosa, inajá (Maximiliana maripa, pupunha (Bactris gasipaes and tucumã (Astrocaryum vulgare. Physicochemical characteristics, fatty acids and triacylglycerol (TAG contents were analyzed by HPLC and GC. The proximate composition of the fruits was also analyzed. The results relating to acidity, peroxide value and polar compounds indicate good quality of the oils obtained. Oleic acid ranging from 39.2 to 71.6% and palmitic acid ranging from 20.8 to 39.6% were the two major fatty acids in all the samples. The oils from inajá were characterized by the presence of significant amounts of lauric (4.6% and miristic (10.7% acids while in bacaba, buriti, pupunha and tucumã, as in most edible vegetable oils, only the fatty acids of 16 and 18 carbon atoms were present. Accordingly, the major TAG species in all the samples were POP, POO and OOO. The mesocarp of the palm fruit had a high content in lipids ranging from 17.0% for pupunha to 38.3% for bacaba, expressed as dry basis.Las palmeras nativas de la familia Arecaceae constituyen recursos alimentarios de gran importancia en la región amazónica. A pesar de su diversidad y utilidad, muchas especies son poco conocidas por lo que son de interés los estudios dirigidos a conocer la calidad y composición de las especies menos exploradas para evaluar su potencial económico. El objetivo de este estudio fue la caracterización de los aceites obtenidos del mesocarpio

  11. Components Essential Oils in Different Parts of Daucus carota L. var. sativa Hoffm

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The components of the essential oils obtained from different parts of Daucus carota L. var. sativa Hoffm were analyzed. The percentages of the essential oils extracted are 0. 27% (mL/100 g material) for the flowers, 0. 07% for the stems and leaves and 0. 01% for the roots. Fifty-four, Sixty-six and Thirty-three compounds were, respectively,separated and identified from the flowers, the stems and leaves and the roots, among which unsaturated alkene compounds are thirty-nine, thirty-nine and twenty-one, respectively, accounting in turn for up to 90. 21%, 90. 49% and 72. 65% of the total essential oils. Because alkene compounds have double bonds that are easily oxidized, it can be inferred that the components of the essential oils in the different parts of Daucus carota L. var. sativa Hoffm should show an activity of the anti-formation of free radicals to some extent.

  12. Two-component mixture model: Application to palm oil and exchange rate

    Science.gov (United States)

    Phoong, Seuk-Yen; Ismail, Mohd Tahir; Hamzah, Firdaus Mohamad

    2014-12-01

    Palm oil is a seed crop which is widely adopt for food and non-food products such as cookie, vegetable oil, cosmetics, household products and others. Palm oil is majority growth in Malaysia and Indonesia. However, the demand for palm oil is getting growth and rapidly running out over the years. This phenomenal cause illegal logging of trees and destroy the natural habitat. Hence, the present paper investigates the relationship between exchange rate and palm oil price in Malaysia by using Maximum Likelihood Estimation via Newton-Raphson algorithm to fit a two components mixture model. Besides, this paper proposes a mixture of normal distribution to accommodate with asymmetry characteristics and platykurtic time series data.

  13. Effect of Light Spectral Quality on Essential Oil Components in Ocimum Basilicum and Salvia Officinalis Plants

    Directory of Open Access Journals (Sweden)

    A. S. IVANITSKIKH

    2014-07-01

    Full Text Available In plants grown with artificial lighting, variations in light spectral composition can be used for the directed biosynthesis of the target substances including essential oils, e.g. in plant factories. We studied the effect of light spectral quality on the essential oil composition in Ocimum basilicum and Salvia officinalis plants grown in controlled environment. The variable-spectrum light modules were designed using three types of high-power light-emitting diodes (LEDs with emission peaked in red, blue and red light, white LEDs, and high-pressure sodium lamps as reference. Qualitative and quantitative essential oil determinations were conducted using gas chromatography with mass selective detection and internal standard method.Sweet basil plant leaves contain essential oils (са. 1 % including linalool, pinene, eugenol, camphor, cineole, and other components. And within the genetic diversity of the species, several cultivar groups can be identified according to the flavor (aroma perceived by humans: eugenol, clove, camphor, vanilla basil. Essential oil components produce particular flavor of the basil leaves. In our studies, we are using two sweet basil varieties differing in the essential oil qualitative composition – “Johnsons Dwarf” (camphor as a major component of essential oils and “Johnsons Lemon Flavor” (contains large amount of citral defining its lemon flavor.In sage, essential oil composition is also very variable. As for the plant responses to the light environment, the highest amount of the essential oils was observed at the regimes with white and red + blue LED light. And it was three times less with red light LEDs alone. In the first two environments, thujone accumulation was higher in comparison with camphor, while red LED light and sodium lamp light favored camphor biosynthesis (three times more than thujone. The highest amount of eucalyptol was determined in plants grown with red LEDs.

  14. Oil classification using X-ray scattering and principal component analysis

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Danielle S.; Souza, Amanda S.; Lopes, Ricardo T., E-mail: dani.almeida84@gmail.com, E-mail: ricardo@lin.ufrj.br, E-mail: amandass@bioqmed.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Oliveira, Davi F.; Anjos, Marcelino J., E-mail: davi.oliveira@uerj.br, E-mail: marcelin@uerj.br [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil). Inst. de Fisica Armando Dias Tavares

    2015-07-01

    X-ray scattering techniques have been considered promising for the classification and characterization of many types of samples. This study employed this technique combined with chemical analysis and multivariate analysis to characterize 54 vegetable oil samples (being 25 olive oils)with different properties obtained in commercial establishments in Rio de Janeiro city. The samples were chemically analyzed using the following indexes: iodine, acidity, saponification and peroxide. In order to obtain the X-ray scattering spectrum, an X-ray tube with a silver anode operating at 40kV and 50 μA was used. The results showed that oils cab ne divided in tow large groups: olive oils and non-olive oils. Additionally, in a multivariate analysis (Principal Component Analysis - PCA), two components were obtained and accounted for more than 80% of the variance. One component was associated with chemical parameters and the other with scattering profiles of each sample. Results showed that use of X-ray scattering spectra combined with chemical analysis and PCA can be a fast, cheap and efficient method for vegetable oil characterization. (author)

  15. The relationship of antioxidant components and antioxidant activity of sesame seed oil.

    Science.gov (United States)

    Wan, Yin; Li, Huixiao; Fu, Guiming; Chen, Xueyang; Chen, Feng; Xie, Mingyong

    2015-10-01

    Although sesame seed oil contains high levels of unsaturated fatty acids and even a small amount of free fatty acids in its unrefined flavored form, it shows markedly greater stability than other dietary vegetable oils. The good stability of sesame seed oil against autoxidation has been ascribed not only to its inherent lignans and tocopherols but also to browning reaction products generated when sesame seeds are roasted. Also, there is a strong synergistic effect among these components. The lignans in sesame seed oil can be categorized into two types, i.e. inherent lignans (sesamin, sesamolin) and lignans mainly formed during the oil production process (sesamol, sesamolinol, etc.). The most abundant tocopherol in sesame seed oil is γ-tocopherol. This article reviews the antioxidant activities of lignans and tocopherols as well as the browning reaction and its products in sesame seed and/or its oil. It is concluded that the composition and structure of browning reaction products and their impacts on sesame ingredients need to be further studied to better explain the remaining mysteries of sesame oil. © 2014 Society of Chemical Industry.

  16. Application of PLE for the determination of essential oil components from Thymus vulgaris L.

    Science.gov (United States)

    Dawidowicz, Andrzej L; Rado, Ewelina; Wianowska, Dorota; Mardarowicz, Marek; Gawdzik, Jan

    2008-08-15

    Essential plants, due to their long presence in human history, their status in culinary arts, their use in medicine and perfume manufacture, belong to frequently examined stock materials in scientific and industrial laboratories. Because of a large number of freshly cut, dried or frozen plant samples requiring the determination of essential oil amount and composition, a fast, safe, simple, efficient and highly automatic sample preparation method is needed. Five sample preparation methods (steam distillation, extraction in the Soxhlet apparatus, supercritical fluid extraction, solid phase microextraction and pressurized liquid extraction) used for the isolation of aroma-active components from Thymus vulgaris L. are compared in the paper. The methods are mainly discussed with regard to the recovery of components which typically exist in essential oil isolated by steam distillation. According to the obtained data, PLE is the most efficient sample preparation method in determining the essential oil from the thyme herb. Although co-extraction of non-volatile ingredients is the main drawback of this method, it is characterized by the highest yield of essential oil components and the shortest extraction time required. Moreover, the relative peak amounts of essential components revealed by PLE are comparable with those obtained by steam distillation, which is recognized as standard sample preparation method for the analysis of essential oils in aromatic plants.

  17. Simultaneous HPLC determination of 22 components of essential oils; method robustness with experimental design

    Directory of Open Access Journals (Sweden)

    A Porel

    2014-01-01

    Full Text Available The aim of the present study was the development and validation of a simple, precise and specific reversed phase HPLC method for the simultaneous determination of 22 components present in different essential oils namely cinnamon bark oil, caraway oil and cardamom fruit oil. The chromatographic separation of all the components was achieved on Wakosil-II C 18 column with mixture of 30 mM ammonium acetate buffer (pH 4.7, methanol and acetonitrile in different ratio as mobile phase in a ternary linear gradient mode. The calibration graphs plotted with five different concentrations of each component were linear with a regression coefficient R 2 >0.999. The limit of detection and limit of quantitation were estimated for all the components. Effect on analytical responses by small and deliberate variation of critical factors was examined by robustness testing with Design of Experiment employing Central Composite Design and established that this method was robust. The method was then validated for linearity, precision, accuracy, specificity and demonstrated to be applicable to the determination of the ingredients in commercial sample of essential oil.

  18. A Study of the Properties of Electrical Insulation Oils and of the Components of Natural Oils

    Directory of Open Access Journals (Sweden)

    Milan Spohner

    2012-01-01

    Full Text Available This paper presents a study of the electrical and non-electrical properties of insulating oils. For the correct choice of an electrical insulation oil, it is necessary to know its density, dynamic viscosity, dielectric constant, loss number and conductivity, and the effects of various exposure factors. This paper deals with mathematical and physical principles needed for studying and making correct measurements of the dynamic viscosity, density and electrical properties of insulation oils. Rheological properties were measured using an A&D SV-10 vibratory viscometer, and analytical balance with density determination kit, which operates on the principle of Archimedes’ law. Dielectric properties were measured using a LCR meter Agilent 4980A with connected with the Agilent 16452A test fixture for dielectric liquids.

  19. Changes in the Chemical Components of Light Crude Oil During Simulated Short Term Weathering

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To unambiguously identify spilled oils and to link them to the known sources are extremely important in settling questions of environmental impact and legal liability. The fate and behavior of spilled oils in the environment depend on a number of physicochemical and biological factors. This paper presents the results regarding changes in chemical composition of light crude oil during simulated short-term weathering based on natural environmental conditions. The results show that the saturated hydrocarbons of the light crude oil mainly distribute between n-C8 and n-C23 and the most abundant n-alkanes are found in the n-C10 to n-C16. The main chemical components of the light crude oil are n-alkanes and isoprenoids. The aromatic compounds are subordinate chemical components. Under the conditions of the weathering simulation experiment, n-alkanes less than n-C12, toluene and 1,3-dimethyl benzene are lost after 1 d weathering, the n-C13, n-C14, naphthalene and 2-methyl-naphthalene are lost on the fifth day of weathering, and n-C15 alkane components show certain weatherproof capability. The ratios n-C17/pristane and n-C18/phytane are unaltered and can be used to identify the source of the light crude oil during the first 8 d of weathering. After 21 d, the ratio pristine/phytane can not provide much information on the source of the spilled light crude oil. Triterpanes (m/z 191) as biomarker compounds of light crude oil are more valuable.

  20. The identification of major component of temu kunci (Kaemferia pandurata Roxb. essential oils on different altitude

    Directory of Open Access Journals (Sweden)

    RETNA BANDRIATI ARNIPUTRI

    2007-04-01

    Full Text Available The aims of this study was to know the major component of essential oils of Temu Kunci (Kaemferia pandurata Roxb. on a different altitude. This research was carried out by method of Stahl destilation at BPTO and GCMS Cromatography at FMIPA UGM for both of from Kerjo (350 m asl and Jumapolo (450 m asl. The difference of altitude of temu kunci’s lives on, the same of major component of essential oil but the content among them was different.

  1. Essential oils in food preservation: mode of action, synergies, and interactions with food matrix components

    Directory of Open Access Journals (Sweden)

    Morten eHyldgaard

    2012-01-01

    Full Text Available Essential oils are aromatic and volatile liquids extracted from plants. The chemicals in essential oils are secondary metabolites, which play an important role in plant defence as they often possess antimicrobial properties. The interest in essential oils and their application in food preservation has been amplified in recent years by an increasingly negative consumer perception of synthetic preservatives. Furthermore, food-borne diseases are a growing public health problem worldwide, calling for more effective preservation strategies. The antibacterial properties of essential oils and their constituents have been documented extensively. Pioneering work has also elucidated the mode of action of a few essential oil constituents, but detailed knowledge about most of the compounds' mode of action is still lacking. This knowledge is particularly important to predict their effect on different microorganisms, how they interact with food matrix components, and how they work in combination with other antimicrobial compounds. The main obstacle for using essential oil constituents as food preservatives is that they are most often not potent enough as single components, and they cause negative organoleptic effects when added in sufficient amounts to provide an antimicrobial effect. Exploiting synergies between several compounds has been suggested as a solution to this problem. However, little is known about which interactions lead to synergistic, additive, or antagonistic effects. Such knowledge could contribute to design of new and more potent antimicrobial blends, and to understand the interplay between the constituents of crude essential oils. The purpose of this review is to provide an overview of current knowledge about the antibacterial properties and antibacterial mode of action of essential oils and their constituents, and to identify research avenues that can facilitate implementation of essential oils as natural preservatives in foods.

  2. Essential oils in food preservation: mode of action, synergies, and interactions with food matrix components.

    Science.gov (United States)

    Hyldgaard, Morten; Mygind, Tina; Meyer, Rikke Louise

    2012-01-01

    Essential oils are aromatic and volatile liquids extracted from plants. The chemicals in essential oils are secondary metabolites, which play an important role in plant defense as they often possess antimicrobial properties. The interest in essential oils and their application in food preservation has been amplified in recent years by an increasingly negative consumer perception of synthetic preservatives. Furthermore, food-borne diseases are a growing public health problem worldwide, calling for more effective preservation strategies. The antibacterial properties of essential oils and their constituents have been documented extensively. Pioneering work has also elucidated the mode of action of a few essential oil constituents, but detailed knowledge about most of the compounds' mode of action is still lacking. This knowledge is particularly important to predict their effect on different microorganisms, how they interact with food matrix components, and how they work in combination with other antimicrobial compounds. The main obstacle for using essential oil constituents as food preservatives is that they are most often not potent enough as single components, and they cause negative organoleptic effects when added in sufficient amounts to provide an antimicrobial effect. Exploiting synergies between several compounds has been suggested as a solution to this problem. However, little is known about which interactions lead to synergistic, additive, or antagonistic effects. Such knowledge could contribute to design of new and more potent antimicrobial blends, and to understand the interplay between the constituents of crude essential oils. The purpose of this review is to provide an overview of current knowledge about the antibacterial properties and antibacterial mode of action of essential oils and their constituents, and to identify research avenues that can facilitate implementation of essential oils as natural preservatives in foods.

  3. Essential Oils in Food Preservation: Mode of Action, Synergies, and Interactions with Food Matrix Components

    Science.gov (United States)

    Hyldgaard, Morten; Mygind, Tina; Meyer, Rikke Louise

    2012-01-01

    Essential oils are aromatic and volatile liquids extracted from plants. The chemicals in essential oils are secondary metabolites, which play an important role in plant defense as they often possess antimicrobial properties. The interest in essential oils and their application in food preservation has been amplified in recent years by an increasingly negative consumer perception of synthetic preservatives. Furthermore, food-borne diseases are a growing public health problem worldwide, calling for more effective preservation strategies. The antibacterial properties of essential oils and their constituents have been documented extensively. Pioneering work has also elucidated the mode of action of a few essential oil constituents, but detailed knowledge about most of the compounds’ mode of action is still lacking. This knowledge is particularly important to predict their effect on different microorganisms, how they interact with food matrix components, and how they work in combination with other antimicrobial compounds. The main obstacle for using essential oil constituents as food preservatives is that they are most often not potent enough as single components, and they cause negative organoleptic effects when added in sufficient amounts to provide an antimicrobial effect. Exploiting synergies between several compounds has been suggested as a solution to this problem. However, little is known about which interactions lead to synergistic, additive, or antagonistic effects. Such knowledge could contribute to design of new and more potent antimicrobial blends, and to understand the interplay between the constituents of crude essential oils. The purpose of this review is to provide an overview of current knowledge about the antibacterial properties and antibacterial mode of action of essential oils and their constituents, and to identify research avenues that can facilitate implementation of essential oils as natural preservatives in foods. PMID:22291693

  4. Analysis of the essential oil components from different Carum copticumL. samples from Iran

    Directory of Open Access Journals (Sweden)

    Mohammad M Zarshenas

    2014-01-01

    Full Text Available Background: The family Apiaceae is defined with the diversity of essential oil. Fruits of Ajwain (Carum copticum, a famous herb of Apiaceae, accumulate up to 5% essential oil which is remarked as important natural product for food and flavoring industry, as well as pharmacological approaches. It is believed that differences in essential oil profile in a certain plant are resulted from various cultivation situations and locations, time of cultivation and also different extracting method. Objective: Present study aimed to evaluate major components of ten different collected Ajwain samples from random cultivation locations of Iran. Materials and Methods: Samples were individually subjected to hydrodistillation using a Clevenger-type apparatus for the extraction of essential oil. GC/MS analysis for samples was carried out using Agilent technologies model 7890A gas chromatograph with a mass detector. Results: The yield of extracted essential oil was calculated as 2.2 to 4.8% (v/w for ten samples. Major oil components were thymol, para-cymene and gamma-terpinene. Five of ten samples have thymol as the main component with amount of 35.04 to 63.31%. On the other hand, for four samples, para-cymene was major with amount of 40.20 to 57.31% and one sample had gamma-terpinene as main constituent containing 37.43% of total oil. Accordingly, three different chemotypes, thymol, para-cymene and gamma-terpinene can be speculated from collected samples. Conclusion: While these components possess pharmacological effect, screening of different chemotypes not only represent the effect of cultivation situations and locations but also can be beneficial in further investigation.

  5. Relation of sulfur with hydrocarbons in Brazilian heavy and extra-heavy crude oil; Relacao do enxofre com os hidrocarbonetos em petroleos pesados e extra pesados brasileiros

    Energy Technology Data Exchange (ETDEWEB)

    Iorio, Sonia Maria Badaro Mangueira; Guimaraes, Regina Celia Lourenco; Silva, Maria do Socorro A. Justo da [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Costa, Alexander Vinicius Moraes da [Fundacao Gorceix, Ouro Preto, MG (Brazil)

    2008-07-01

    As the occurrence of heavy and extra-heavy oils increases sensitively, their participation in the refineries feeding also becomes greater. Heavy oils usually have lower price than a light one, because they produce lower quality derivatives and it's more difficult to meet the specifications. Crude oils are a complex mixture, mostly compounded by carbon and hydrogen and also by impurities like sulfur, nitrogen, oxygen and metals. Sulfur is the third most abundant component of crude oils, following carbon and hydrogen. In general there is a strong positive correlation between the concentrations of polar compounds (aromatics, resins and asphaltenes), and the sulfur content. This work presents graphically sulfur content and polar compounds concentrations for Brazilian and foreign heavy and extra-heavy oils (< 20 deg API). The results of the data analysis indicate that Brazilian crude oils behave differently from foreign heavy and extra-heavy oils. (author)

  6. The algorithm of measuring parameters of separate oil streams components

    Science.gov (United States)

    Kopteva, A. V.; Voytyuk, I. N.

    2017-02-01

    This paper describes a development in the area of non-contact measurement of moving flows, including mass flow, the number of components and their mass ratios in a multicomponent flow, as well as measurement of flows based on algorithms and functional developed for various industries and production processes. The paper demonstrates that at the core of the proposed systems, there is the physical information field created in the cross section of the moving flow by hard electromagnetic radiation. The substantiation and measurement of the information parameters are performed by the hardware and the software of the automatic measuring system. A new way of statistical pulsation measurements by the radioisotope technique is described, being alternative to the existing stream control methods and allowing improving accuracy of measurements. The basic formula fundamental for the method of calibration characteristics correction is shown.

  7. Multiscale scattering investigations of asphaltene cluster breakup, nanoaggregate dissociation, and molecular ordering.

    Science.gov (United States)

    Hoepfner, Michael P; Fogler, H Scott

    2013-12-10

    Small-angle X-ray and neutron scattering (SAXS/SANS) by asphaltenes in various solvents (toluene, tetrahydrofuran, and 1-methylnaphthalene) at dilute concentrations of asphaltenes are presented and discussed. As asphaltenes are diluted, it was found that the cluster size decreases and follows a fractal scaling law. This observation reveals that asphaltene clusters persist to dilute concentrations and maintain fractal characteristics, regardless of concentration. For the first time, the fraction of asphaltenes that exist in nanoaggregates compared to those molecularly dispersed was estimated from the scattering intensity. Significant dissociation was detected at concentrations similar to the previously reported critical nanoaggregate concentration (CNAC); however, the dissociation was observed to occur gradually as the asphaltene concentration was lowered. Complete dissociation was not detected, and aggregates persisted down to asphaltene concentrations as low as 15 mg/L (0.00125 vol. %). A simplified thermodynamic aggregation model was applied to the measurements, and the free energy change of association per asphaltene-asphaltene interaction was calculated to be approximately -31 kJ/mol. Finally, novel solvent-corrected WAXS results of asphaltene in a liquid environment are presented and reveal three distinct separation distances, in contrast to the two separation distances observed in diffraction studies of solid phase asphaltenes. Significant differences in the WAXS peak positions and shapes between aromatic and nonaromatic solvents suggests that there may be large differences between the solvation shell or conformation of the asphaltene alkyl shell depending on the surrounding liquid environment.

  8. Acaricidal activity and repellency of essential oil from Piper aduncum and its components against Tetranychus urticae.

    Science.gov (United States)

    Araújo, Mário J C; Câmara, Cláudio A G; Born, Flávia S; Moraes, Marcílio M; Badji, César A

    2012-06-01

    The chemical composition of essential oil of leaves of Piper aduncum L., growing wild in a fragment of the Atlantic Rainforest biome in northeastern Brazil, was determined through gas chromatography-mass spectrometry. The acaricidal activity and repellency of the essential oil and its components [dillapiole (0.28 g/ml), α-humulene (0.016 g/ml), (E)-nerolidol (0.0007 g/ml) and β-caryophyllene (0.0021 g/ml)] were evaluated in the laboratory against adults of Tetranychus urticae Koch. The mites were more susceptible to the oil in fumigation tests (LC(50) = 0.01 μl/l of air) than in contact test with closed Petri dish (LC(50) = 7.17 μl/ml); mortality was reduced by approximately 50 % in the latter test. The repellent action of the oil and toxicity by fumigation and contact did not differ significantly from the positive control (eugenol). The repellent activity was attributed to the components (E)-nerolidol, α-humulene and β-caryophyllene, whereas toxicity by fumigation and contact was attributed to β-caryophyllene. The effect of Piper oil and the role of its components regarding host plant preference with a two-choice leaf disk test are also discussed.

  9. Seasonal variation of mono- and sesquiterpenoid components in the essential oil of Dracocephalum kotschyi Boiss.

    Directory of Open Access Journals (Sweden)

    G. Asghari

    2014-10-01

    Full Text Available Background and objectives: Dracocephalum kotschyi is a plant which belongs to the Lamiaceae family and exists mostly in south-west Asian countries, including Iran. This plant is used as antispasmodic, analgesic and anti-inflammatory to treat rheumatoid diseases. Methods: In order to investigate the impact of the harvesting time changes on the quantity and quality of mono- and sesquiterpenoid components of D. kotschyi aerial parts, ten samples were collected from cultivated plants from 19 April to 27 August 2013. Also samples of flower and root were harvested in order to investigate their essential oil components. The essential oils were obtained through hydrodistillation method. The components were studied and identified by GC and GC ⁄ MS systems. Results: The highest yield of the essential oil was obtained on 3 May (1.10% V.W and the lowest on 28 July (0.29% V.W. Totally 55 compounds were identified in the essential oil while the highest percentage belonged to monoterpenes especially the oxygenated ones. Most variations were observed in geraniol (1.40-15.34%, geranyl acetate (trace-14.41% and neryl acetate (0.62-17.51%. The major value in most cases belonged to geranial. Conclusion: the results of this study indicate that the harvesting time of plant is an effective factor in the quality and quantity of theessential oil of Dracocephalum kotschyi.

  10. Chemical components of cold pressed kernel oils from different Torreya grandis cultivars.

    Science.gov (United States)

    He, Zhiyong; Zhu, Haidong; Li, Wangling; Zeng, Maomao; Wu, Shengfang; Chen, Shangwei; Qin, Fang; Chen, Jie

    2016-10-15

    The chemical compositions of cold pressed kernel oils of seven Torreya grandis cultivars from China were analyzed in this study. The contents of the chemical components of T. grandis kernels and kernel oils varied to different extents with the cultivar. The T. grandis kernels contained relatively high oil and protein content (45.80-53.16% and 10.34-14.29%, respectively). The kernel oils were rich in unsaturated fatty acids including linoleic (39.39-47.77%), oleic (30.47-37.54%) and eicosatrienoic acid (6.78-8.37%). The kernel oils contained some abundant bioactive substances such as tocopherols (0.64-1.77mg/g) consisting of α-, β-, γ- and δ-isomers; sterols including β-sitosterol (0.90-1.29mg/g), campesterol (0.06-0.32mg/g) and stigmasterol (0.04-0.18mg/g) in addition to polyphenols (9.22-22.16μgGAE/g). The results revealed that the T. grandis kernel oils possessed the potentially important nutrition and health benefits and could be used as oils in the human diet or functional ingredients in the food industry.

  11. Insecticidal Components from the Essential Oil of Chinese Medicinal Herb, Ligusticum chuanxiong Hort

    Directory of Open Access Journals (Sweden)

    Sha Sha Chu

    2011-01-01

    Full Text Available Essential oil of Chinese medicinal herb, Ligusticum chuanxiong dried rhizome was found to possess insecticidal activity against maize weevils, Sitophilus zeamais. The main components of L. chuanxiong essential oil were Z-3-butylidenephthalide (20.56%, Z-ligustilide (19.61%, 4-terpinenol (8.82%, 4-vinylguaiacol (6.81% and α-selinene (6.01%. Bioactivity-guided chromatographic separation of the essential oil on repeated silica gel columns led to isolate three compounds namely 3-butylidenephthalide, Z-ligustilide and 4-vinylguaiacol. Z-liqustilide and Z-3-butylidenephthalide showed pronounced toxicity against S. zeamais (LD50= 10.23 and 15.81 μg/adult respectively and were more toxic than 4-vinylguaiacol (LD50 = 63.75 μg/adult. The crude essential oil also possessed contact toxicity against S. zeamais (LD50 = 13.09 μg/adult.

  12. Level shift two-components autoregressive conditional heteroscedasticity modelling for WTI crude oil market

    Science.gov (United States)

    Sin, Kuek Jia; Cheong, Chin Wen; Hooi, Tan Siow

    2017-04-01

    This study aims to investigate the crude oil volatility using a two components autoregressive conditional heteroscedasticity (ARCH) model with the inclusion of abrupt jump feature. The model is able to capture abrupt jumps, news impact, clustering volatility, long persistence volatility and heavy-tailed distributed error which are commonly observed in the crude oil time series. For the empirical study, we have selected the WTI crude oil index from year 2000 to 2016. The results found that by including the multiple-abrupt jumps in ARCH model, there are significant improvements of estimation evaluations as compared with the standard ARCH models. The outcomes of this study can provide useful information for risk management and portfolio analysis in the crude oil markets.

  13. Assessment of oil weathering by gas chromatography-mass spectrometry, time warping and principal component analysis

    DEFF Research Database (Denmark)

    Malmquist, Linus M.V.; Olsen, Rasmus R.; Hansen, Asger B.

    2007-01-01

    Detailed characterization and understanding of oil weathering at the molecular level is an essential part of tiered approaches for forensic oil spill identification, for risk assessment of terrestrial and marine oil spills, and for evaluating effects of bioremediation initiatives. Here......, a chemometricbased method is applied to data from two in vitro experiments in order to distinguish the effects of evaporation and dissolution processes on oil composition. The potential of the method for obtaining detailed chemical information of the effects from evaporation and dissolution processes, to determine...... weathering state and to distinguish between various weathering processes is investigated and discussed. The method is based on comprehensive and objective chromatographic data processing followed by principal component analysis (PCA) of concatenated sections of gas chromatography–mass spectrometry...

  14. Componentes funcionales en aceites de pescado y de alga Functional components in fish and algae oils

    Directory of Open Access Journals (Sweden)

    A. Conchillo

    2006-06-01

    Full Text Available Buena parte del desarrollo de nuevos alimentos funcionales está encaminada al descubrimiento o aplicación de componentes de los alimentos que favorezcan la instauración de un perfil lipídico saludable en el organismo. El objetivo del trabajo fue realizar la caracterización de la fracción lipídica de dos tipos de aceites, de pescado y de alga, para valorar su potencial utilización como ingredientes funcionales, tanto en relación con el contenido en ácidos grasos de alto peso molecular como con la presencia de esteroles y otros componentes de la fracción insaponificable. Ambos aceites presentaron una fracción lipídica muy rica en ácidos grasos poliinsaturados ω-3 de alto peso molecular, con un 33,75% en el caso del aceite de pescado y un 43,97% en el de alga, siendo el EPA el ácido graso mayoritario en el pescado y el DHA en el alga. La relación ω-6/ω-3 fue en ambos aceites inferior a 0,4. En cuanto a la fracciσn insaponificable, el aceite de alga presentσ un contenido 3 veces menor de colesterol y una mayor proporciσn de escualeno. El contenido en fitosteroles fue significativamente superior en el aceite de alga.An important area of the development of new functional foods is facussed on finding or applying food components which favour achieving a healthier lipid profile in the organism. The objective of this work was to carry out the characterisation of the lipid fraction of two oils, fish oil and algae oil, to evaluate their potential use as functional ingredients, in relation to the high molecular weight fatty acid content and the presence of sterols and other components of the unsaponificable fraction. Both oils showed a lipid fraction rich in high molecular weight polyunsaturated ω-3 fatty acids, containing a 33.75% in the fish oil and a 43.97% in the algae oil. Eicosapentaenoic acid was the major fatty acid in fish oil, whereas docosahexaenoic was the most abundant fatty acid in algae oil. The ω-6/ω-3 ratio was lower

  15. Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Final technical report, September 20, 1991--September 30, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Guin, J.A.

    1998-12-31

    The overall objective of this project was to investigate the diffusion of coal and petroleum asphaltenes in the pores of a supported catalyst. Experimental measurements together with mathematical modeling was conducted to determine how the diffusion rate of asphaltenes, as well as some model compounds, depended on molecule sizes and shapes. The process of diffusion in the pores of a porous medium may occur by several mechanisms. Hindered diffusion occurs when the sizes of the diffusion molecules are comparable to those of the porous pores through which they are diffusing. Hindered diffusion phenomena have been widely observed in catalytic hydrotreatment of asphaltenes, heavy oils, coal derived liquids, etc. Pore diffusion limitations can be greater in spent catalysts due to the deposition of coke and metals in the pores. In this work, a general mathematical model was developed for the hindered diffusion-adsorption of solute in a solvent onto porous materials, e. g. catalysts, from a surrounding bath. This diffusion model incorporated the nonuniformities of pore structures in the porous media. A numerical method called the Method of Lines was used to solve the nonlinear partial differential equations resulting from the mathematical model. The accuracy of the numerical solution was verified by both a mass balance in the diffusion system and satisfactory agreement with known solutions in several special cases.

  16. Probing the carbonyl functionality of a petroleum resin and asphaltene through oximation and schiff base formation in conjunction with N-15 NMR

    Science.gov (United States)

    Thorn, Kevin A.; Cox, Larry G.

    2015-01-01

    Despite recent advances in spectroscopic techniques, there is uncertainty regarding the nature of the carbonyl groups in the asphaltene and resin fractions of crude oil, information necessary for an understanding of the physical properties and environmental fate of these materials. Carbonyl and hydroxyl group functionalities are not observed in natural abundance 13C nuclear magnetic resonance (NMR) spectra of asphaltenes and resins and therefore require spin labeling techniques for detection. In this study, the carbonyl functionalities of the resin and asphaltene fractions from a light aliphatic crude oil that is the source of groundwater contamination at the long term USGS study site near Bemidji, Minnesota, have been examined through reaction with 15N-labeled hydroxylamine and aniline in conjunction with analysis by solid and liquid state 15N NMR. Ketone groups were revealed through 15N NMR detection of their oxime and Schiff base derivatives, and esters through their hydroxamic acid derivatives. Anilinohydroquinone adducts provided evidence for quinones. Some possible configurations of the ketone groups in the resin and asphaltene fractions can be inferred from a consideration of the likely reactions that lead to heterocyclic condensation products with aniline and to the Beckmann reaction products from the initially formed oximes. These include aromatic ketones and ketones adjacent to quaternary carbon centers, β-hydroxyketones, β-diketones, and β-ketoesters. In a solid state cross polarization/magic angle spinning (CP/MAS) 15N NMR spectrum recorded on the underivatized asphaltene as a control, carbazole and pyrrole-like nitrogens were the major naturally abundant nitrogens detected.

  17. Probing the Carbonyl Functionality of a Petroleum Resin and Asphaltene through Oximation and Schiff Base Formation in Conjunction with N-15 NMR.

    Directory of Open Access Journals (Sweden)

    Kevin A Thorn

    Full Text Available Despite recent advances in spectroscopic techniques, there is uncertainty regarding the nature of the carbonyl groups in the asphaltene and resin fractions of crude oil, information necessary for an understanding of the physical properties and environmental fate of these materials. Carbonyl and hydroxyl group functionalities are not observed in natural abundance 13C nuclear magnetic resonance (NMR spectra of asphaltenes and resins and therefore require spin labeling techniques for detection. In this study, the carbonyl functionalities of the resin and asphaltene fractions from a light aliphatic crude oil that is the source of groundwater contamination at the long term USGS study site near Bemidji, Minnesota, have been examined through reaction with 15N-labeled hydroxylamine and aniline in conjunction with analysis by solid and liquid state 15N NMR. Ketone groups were revealed through 15N NMR detection of their oxime and Schiff base derivatives, and esters through their hydroxamic acid derivatives. Anilinohydroquinone adducts provided evidence for quinones. Some possible configurations of the ketone groups in the resin and asphaltene fractions can be inferred from a consideration of the likely reactions that lead to heterocyclic condensation products with aniline and to the Beckmann reaction products from the initially formed oximes. These include aromatic ketones and ketones adjacent to quaternary carbon centers, β-hydroxyketones, β-diketones, and β-ketoesters. In a solid state cross polarization/magic angle spinning (CP/MAS 15N NMR spectrum recorded on the underivatized asphaltene as a control, carbazole and pyrrole-like nitrogens were the major naturally abundant nitrogens detected.

  18. Hydrogen-bonding studies of pyridine and 0-phenylphenol with coal asphaltenes by multi-nuclei magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Schweighardt, F.K.; Friedel, R.A.; Retcofsky, H.L.

    1976-01-01

    Proton, carbon, and nitrogen-14 nuclear magnetic resonance studies are reported of hydrogen bonding between the OH proton of o-phenylphenol (OPP) and the nitrogen electron donor of pyridine (Py). Data are also reported on the hydrogen bonding of the acid and base components of coal-derived asphaltenes with the model system. Determination was made of the equilibrium constant of the 1:1 complex between OPP and Py from the proton NMR studies. Qualitative results are reported from the /sup 13/C and /sup 14/N studies of the model system (OPP-Py) with the individual asphaltene fractions. Because of the recent renewed interest in coal liquefaction this investigation may provide a starting point for future research. 7 figures.

  19. Cooee bitumen II: Stability of linear asphaltene nanoaggregates

    CERN Document Server

    Lemarchand, Claire A; Dyre, Jeppe C; Hansen, Jesper S

    2014-01-01

    Asphaltene and smaller aromatic molecules tend to form linear nanoaggregates in bitumen.Over the years bitumen undergoes chemical aging and during this process, the size of the nanoaggregate increases. This increase is associated with an increase in viscosity and brittleness of the bitumen, eventually leading to road deterioration. This paper focuses on understanding the mechanisms behind nanoaggregate size and stability. We used molecular dynamics simulations to quantify the probability of having a nanoaggregate of a given size in the stationary regime. To model this complicated behavior, we chose first to consider the simple case where only asphaltene molecules are counted in a nanoaggregate. We used a master equation approach and a related statistical mechanics model. The linear asphaltene nanoaggregates behave as a rigid linear chain. The most complicated case where all aromatic molecules are counted in a nanoaggregate is then discussed. The linear aggregates where all aromatic molecules are counted seem ...

  20. Measuring the Spread Components of Oil and Gas Companies from CDS

    Directory of Open Access Journals (Sweden)

    Juliano Ribeiro de Almeida

    2012-04-01

    Full Text Available In this paper, we use the information from the credit default swap market to measure the main components of the oil and gas companies spread. Using nearly 20 companies of this industry with different ratings and nearly 80 bonds, the result was that the majority of the oil and gas spread is due to the default risk. We also find that the spread component related to the non-default is strongly associated with some liquidity measures of bond markets, what suggest that liquidity has a very important role in the valuation of fixed income assets. On the other side, we do not find evidence that the non-default component of the spread is related to tax matters.

  1. Study of Growth, Essential Oil Percentage and Essential Oil Component of Achilleaspp Under Shoushtar Climatic Condition in Fall Planting

    Directory of Open Access Journals (Sweden)

    R. Farhodi

    2016-02-01

    Full Text Available Introduction: Spices and herbs are part of daily food intake in many regions of the world. They have been used as natural sources of flavorings and preservatives. Yarrow (Achillea spp. belongs to Asteraceae family and more than 100 species have been recognized in this genus. This plantis reportedto be a diaphoretic, astringent, tonic, stimulant and mild aromatic plant. It contains isovaleric acid, salicylic acid, asparagin, sterols, flavonoids, bitters, tannins, and coumarins. The plant also has a long history as a powerful 'healing herb' used topically for wounds, cuts and abrasions. The genus name Achillea is derived from the mythical Greek character, Achilles. Action is also reflected in some of the common names mentioned below, such as staunchweed and soldier's woundwort. The genus Achillea is a well-known medicinal plant, widely used in folk medicine against gastrointestinal disorders such as lack of appetite. This plant is native to Europe and Western Asia but isalso found in Australia, New Zealand and North America. Nineteen species of Achillea have been recognized in Iran distributed in different geographical and ecological regions. Achillea spp. are diaphoretic, astringent, tonic, stimulant and mild aromatic. Major components in Achillea spp. essential oil are sabinene, 1,8-cineole, camphor, α-pinene, β-pinene, borneol and bornyl acetate. The aim of this work is to investigate growth, essential oil yield and chemical composition of essential oils of A. eriophora, A. millefolium, A. biebersteinii and A. tenuifolia. Material and Methods: This study investigated the growth and essential oil yield of four Achillea species in the North of Khuzestan situation,Shoushtar, in2008-2010. An experiment was conducted in combined analysis based on complete block design with 4 replicates. Achillea species examined concluded Achillea eriophora, A. millefolium, A. biebersteinii and A. nobilis. Seedling establishment, essential oil percentage andyield

  2. Methods for estimating properties of hydrocarbons comprising asphaltenes based on their solubility

    Energy Technology Data Exchange (ETDEWEB)

    Schabron, John F.; Rovani, Jr., Joseph F.

    2016-10-04

    Disclosed herein is a method of estimating a property of a hydrocarbon comprising the steps of: preparing a liquid sample of a hydrocarbon, the hydrocarbon having asphaltene fractions therein; precipitating at least some of the asphaltenes of a hydrocarbon from the liquid sample with one or more precipitants in a chromatographic column; dissolving at least two of the different asphaltene fractions from the precipitated asphaltenes during a successive dissolution protocol; eluting the at least two different dissolved asphaltene fractions from the chromatographic column; monitoring the amount of the fractions eluted from the chromatographic column; using detected signals to calculate a percentage of a peak area for a first of the asphaltene fractions and a peak area for a second of the asphaltene fractions relative to the total peak areas, to determine a parameter that relates to the property of the hydrocarbon; and estimating the property of the hydrocarbon.

  3. Seasonal variability of the main components in essential oil of Mentha × piperita L.

    Science.gov (United States)

    Grulova, Daniela; De Martino, Laura; Mancini, Emilia; Salamon, Ivan; De Feo, Vincenzo

    2015-02-01

    Mentha × piperita is an important and commonly used flavoring plant worldwide. Its constituents, primarily menthol and menthone, change in the essential oil depending on internal and external factors, of which environmental conditions appear very important. The experiment was established in 2010 for three vegetation season, in order to observe the quantitative changes of the main components of peppermint. The determination of menthol, menthone, limonene, menthyl acetate, menthofuran and β-caryophyllene was registered. In the experimental season 2011 and 2012 a higher mean temperature than in 2010 and extreme rainfall in July 2011 and 2012 were recorded. Different environmental conditions affected the development of M. × piperita plants and the content and composition of the essential oil. Seasonal and maturity variations are interlinked with each other, because the specific ontogenic growth stage differed as the season progressed. Fluctuations in monthly and seasonal temperature and precipitation patterns affected the quality of peppermint essential oil. © 2014 Society of Chemical Industry.

  4. Antimicrobial activity of essential oil components against potential food spoilage microorganisms.

    Science.gov (United States)

    Klein, G; Rüben, C; Upmann, M

    2013-08-01

    The antimicrobial activity of six essential oil components against the potential food spoilage bacteria Aeromonas (A.) hydrophila, Escherichia (E.) coli, Brochothrix (B.) thermosphacta, and Pseudomonas (P.) fragi at single use and in combination with each other was investigated. At single use, the most effective oil components were thymol (bacteriostatic effect starting from 40 ppm, bactericidal effect with 100 ppm) and carvacrol (50 ppm/100 ppm), followed by linalool (180 ppm/720 ppm), α-pinene (400 ppm/no bactericidal effect), 1,8-cineol (1,400 ppm/2,800 ppm), and α-terpineol (600 ppm/no bactericidal effect). Antimicrobial effects occurred only at high, sensorial not acceptable concentrations. The most susceptible bacterium was A. hydrophila, followed by B. thermosphacta and E. coli. Most of the essential oil component combinations tested showed a higher antimicrobial effect than tested at single use. Antagonistic antimicrobial effects were observed particularly against B. thermosphacta, rarely against A. hydrophila. The results show that the concentration of at least one of the components necessary for an antibacterial effect is higher than sensorial acceptable. So the use of herbs with a high content of thymol, carvacrol, linalool, 1,8-cineol, α-pinene or α-terpineol alone or in combination must be weighted against sensorial quality.

  5. REVIEWS ON PHYTOTOXIC EFFECTS OF ESSENTIAL OILS AND THEIR INDIVIDUAL COMPONENTS: NEWS APPROACH FOR WEEDS MANAGEMENT.

    Directory of Open Access Journals (Sweden)

    Ismail Amri

    2013-02-01

    Full Text Available Currently, the use of synthetic chemicals to control weeds raises several concerns related to environment and human health. An alternative is to use natural products that possess good efficacy and are environmentally friendly. Among those, essential oils have been extensively tested to assess their herbicidal properties as valuable natural resource. The essential oils whose phytotoxic activities have been demonstrated, as well as the importance of the synergistic effects among their components are the main focus of this review. Essential oils are volatile mixtures of hydrocarbons with a diversity of functional groups (ketones, ether, ester, alcohol, phenol, aldehyde ... and their herbicidal activity has been linked to the presence of monoterpenes and sesquiterpenes. However, in some cases, these chemicals can work synergistically, improving their effectiveness. Among the plant families with promising essential oils used as herbicide, Lamiaceae, Myrtaceae, Asteraceae and Anacardiaceae are the most cited. Individual compounds present in these mixtures with high activity include α-pinene, limonene, 1,8-cineole, carvacrol, camphor and thymol. Finally, although from an economical point of view synthetic chemicals are still more frequently used as herbicide than essential oils, these natural products have the potential to provide efficientand safer herbicide for humans and the environment.

  6. THE ESSENTIAL OIL OF LEMON BALM (Melissa officinalis L.), ITS COMPONENTS AND USING FIELDS

    OpenAIRE

    BAHTİYARCA BAĞDAT, Reyhan; Coşge, Belgin

    2012-01-01

    Lemon balm (Melissa officinalis L.), member of Lamiaceae (formerly Labiatae) family, is one of the important medicinal plant species. Today, it is used in different branches of industry (such as medicine, perfume, cosmetic, and food etc.) in many countries of the world. The main components of lemon balm essential oil, ranged from 0.01 to 0.25%, are 39% citronellal, 33% citral (citronellol, linalool) and geraniol. It is traditionally used as a mild sedative, spasmolytic and antibacterial agent...

  7. Improved minimum miscibility pressure correlation for CO2 flooding using various oil components and their effects

    Science.gov (United States)

    Lai, Fengpeng; Li, Zhiping; Hu, Xiaoqing

    2017-03-01

    Carbon dioxide (CO2) flooding is an effective method of enhanced oil recovery (EOR) that has become one of the most important EOR processes. One of the key factors in the design of a CO2 injection project is the minimum miscibility pressure (MMP), whereas local sweeping efficiency during gas injection is dependent on the MMP. There are many empirical correlation analyses for the MMP calculation. However, these analyses focus on the molecular weight of the C5+ or C7+ fraction, and do not emphasize the effects of various components on MMP. Our study aims to develop an improved CO2-oil MMP correlation analysis that includes parameters such as reservoir temperature and various oil mole fractions. Here, correlation analysis was performed to define the influence of various components on the MMP using various data from 45 oilfields which have experimental CO2-oil MMP and oil compositions readily available. Thirty of the data sets were used to develop an improved correlation, and the other 15 data sets were used to verify the correlation. It was found that the mole fraction of C3 and C6 were the main factors that affected MMP. There was a good quadratic polynomial relationship between the mole fraction of C3 and MMP, and the relationship also existed between the mole fraction of C6 and MMP. The results do not include the molecular weight of the C5+ or C7+ fraction like other common correlations. Nine popular correlations were then used to also predict the MMP, and the comparison showed that the improved CO2-oil MMP correlation defined here was a better estimate. The correlation was then used in Dongshisi and Fuyu oilfields to assess EOR potential, the results also indicated that MMP increased over the course of the CO2 flooding process. This increase shows that it would be more difficult to achieve a mixed phase between crude oil and CO2, therefore the oil recovery would be difficult to further improve towards the end of injection.

  8. Kinetic features of pyrolysis of asphaltenes from lignite semicoking tar

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Ryl' tsova, S.V.; Rozental, D.A.; Proskuryakov, V.A.; Polovetskaya, O.S.

    2000-07-01

    The kinetic features of accumulation of the main gaseous and some liquid products in pyrolysis of asphaltenes from lignite semicoking tar at 750-900{degree}C (contact time 0.5-6.0 s) were studied. The overall reaction order of accumulation of certain compounds was determined, and possible pathways for their formation were suggested.

  9. A Thermodynamic Mixed-Solid Asphaltene Precipitation Model

    DEFF Research Database (Denmark)

    Lindeloff, Niels; Heidemann, R.A.; Andersen, Simon Ivar

    1998-01-01

    A simple model for the prediction of asphaltene precipitation is proposed. The model is based on an equation of state and uses standard thermodynamics, thus assuming that the precipitation phenomenon is a reversible process. The solid phase is treated as an ideal multicomponent mixture. An activity...

  10. Cooee bitumen. II. Stability of linear asphaltene nanoaggregates

    DEFF Research Database (Denmark)

    Lemarchand, Claire; Schrøder, Thomas; Dyre, J. C.;

    2014-01-01

    Asphaltene and smaller aromatic molecules tend to form linear nanoaggregates in bitumen. Over the years bitumen undergoes chemical aging and during this process, the size of the nanoaggregate increases. This increase is associated with an increase in viscosity and brittleness of the bitumen...

  11. A combined QCM and XPS investigation of asphaltene adsorption on metal surfaces.

    Science.gov (United States)

    Rudrake, Amit; Karan, Kunal; Horton, J Hugh

    2009-04-01

    To investigate asphaltene-metal interactions, a combined quartz crystal microbalance (QCM) and X-ray photoelectron spectroscopy (XPS) study of asphaltene adsorption on a gold surface was conducted. Adsorption experiments were conducted at 25 degrees C with solutions of asphaltenes in toluene at concentrations ranging from 50 to 1500 ppm. QCM measurements yielded information on the kinetics of adsorption and further assessment of the data allowed the estimation of equilibrium adsorption levels. XPS analysis of adsorbed and bulk asphaltene demonstrated the presence of carboxylic, thiophenic, sulfide, pyridinic and pyrrolic type functional groups. The intensity of the main carbon (C-H) peak was related to surface coverage of adsorbed asphaltene as a function of asphaltene concentration by a simple mathematical model. The mass adsorption data from the QCM experiments also allowed estimation of the surface coverage, which was compared to those from XPS analyses. Surface coverage estimates as a function of asphaltene concentration could be described by a Langmuir (type-I) isotherm. The free energy of asphaltene adsorption was estimated to be -26.8+/-0.1 and -27.3+/-0.1 kJ/mol from QCM and XPS data, respectively assuming asphaltene molar mass of 750 g/gmol. QCM and XPS data was also analyzed to estimate adsorbed layer thickness after accounting for surface coverage. The thickness of the adsorbed asphaltene estimated from both XPS and QCM data analyses ranged from 6-8 nm over the entire range of adsorption concentrations investigated.

  12. Analysis of sterol and other components present in unsaponifiable matters of mahua, sal and mango kernel oil.

    Science.gov (United States)

    Dhara, Rupali; Bhattacharyya, Dipak K; Ghosh, Mahua

    2010-01-01

    The amount and characterization of phytosterol and other minor components present in three Indian minor seed oils, mahua (Madhuca latifolia), sal (Shorea robusta) and mango kernel (Mangifera indica), have been done. Theses oils have shown commercial importance as cocoa-butter substitutes because of their high symmetrical triglycerides content. The conventional thin layer chromatography (TLC), gas chromatography (GC) & gas chromatography-mass spectroscopy (GC-MS) techniques were used to characterize the components and the high performance thin layer chromatography (HPTLC) technique was used to quantify the each group of components. The experimental data showed that the all the three oils are rich in sterol content and among all the sterols, beta-sitosterol occupies the highest amount. Sal oil contains appreciable amount of cardenolides, gitoxigenin. Tocopherol is present only in mahua oil and oleyl alcohol is present in mango kernel oil. Hydrocarbon, squalene, is present in all the three oils. The characterization of these minor components will help to detect the presence of the particular oil in specific formulations and to assess its stability as well as nutritional quality of the specific oil.

  13. Asphalts and asphaltenes: Macromolecular structure, precipitation properties, and flow in porous media

    Science.gov (United States)

    Rassamdana, Hossein

    Depending on rock and fluid properties, more than 50% of reservoir oil in place is normally produced by enhanced oil recovery (EOR) methods. Among the EOR techniques, miscible flooding is one of the most efficient and widely-used methods. However, this method can suffer from the formation and precipitation of asphalt aggregates. In addition, asphalt deposition is also a major hindrance to heavy oil production, and even primary recovery operations. Asphalt deposition can alter the reservoir rock properties, fluid saturation distribution, fluid flow properties, and eventually the ultimate oil recovery. The shortage of studies on the macromolecular structure and growth mechanisms of asphalt particles is the main reason for the unsuccessful modeling of their precipitation properties. The equivocal behavior of asphalt under some specific conditions could be the other reason. In this research we look at the problem of asphalt formation, flow, and precipitation from three different angles. We analyze extensive small-angle X-ray and neutron scattering data, precipitation data, and molecular weight distribution measurements, and show that they all suggest conclusively that asphalts and asphaltenes are fractal aggregates, and their growth mechanisms are diffusion-limited particle (DLP) and diffusion-limited cluster-cluster (DLCC) aggregation processes. These results lead us to development of a scaling equation of state for predicting asphalt precipitation properties, such as its onset and amount of precipitation. Another result of our study is an analytical equation for modeling the molecular weight distribution of asphalt and asphaltene aggregates. In addition, asphalt phase behavior in miscible and immiscible injections is studied. The effect of the governing thermodynamic factors, such as the pressure, temperature, and composition of the oil and precipitation agents, on the asphalt aggregation and disaggregation processes are investigated. Finally, a model is developed to

  14. The Relationship between the Viscosity and Fraction Characteristcs of the Heavy Oil of Shengli Oil Field%胜利油田稠油黏度与其组分性质的关系研究

    Institute of Scientific and Technical Information of China (English)

    盖平原

    2011-01-01

    选取黏度分别属于普通稠油、特稠油、超稠油、特超稠油的GD排15-0、GD排13-10、单56-16-10、56-9-11、单113-P1、郑411系列、坨826系列等13个胜利油田稠油样品,利用液相色谱法将其分离成饱和分、芳香分、胶质、沥青质四个组分;采用VPO法分别测定各组分的平均相对分子质量;采用元素分析仪和原子吸收光谱仪测定其元素组成与金属含量.研究结果表明,沥青质含量是影响稠油黏度的主要因素,胶质含量对原油黏度也有重要影响,稠油黏度随胶质、沥青质总量增大而增加;胶质沥青质组分的高相对分子质量是其影响体系黏度的主要原因;组分杂原子含量和金属元素含量对稠油黏度均有一定影响.%The 13 samples including CD Pail 5-0, CD Pail 3-10, Shan 56-16-10, 56-9-11, Shan 113-P1, Zheng 411 and Tuo 826, which were classified into ordinary heavy oil, heavy oil, extra heavy oil and super-heavy oil, were fractioned into four components of saturates, aromatics, resins, and asphaltenes by liquid chromatogram.The relative molecular mass of fractions was measured by VPO method, and the element composition and the mental content of fractions were measured by elemental analysis and atomic absorption spectrometry.It could be concluded that the content of asphaltenes and resins played a decisive role in the viscosity of heavy oil.The viscosity of the heavy oil would be great if the content of resins and asphaltenes was high.The high relative molecular mass was the main reason for the resins and asphaltenes impacting the viscosity of the samples.The viscosity of heavy oil was also affected by the content of heteroatom or metals of fraction.

  15. WETTABILITY AND PREDICTION OF OIL RECOVERY FROM RESERVOIRS DEVELOPED WITH MODERN DRILLING AND COMPLETION FLUIDS

    Energy Technology Data Exchange (ETDEWEB)

    Jill S. Buckley; Norman R. Morrow

    2005-04-01

    Exposure to crude oil in the presence of an initial brine saturation can render rocks mixed-wet. Subsequent exposure to components of synthetic oil-based drilling fluids can alter the wetting toward less water-wet or more oil-wet conditions. Mixing of the non-aromatic base oils used in synthetic oil-based muds (SBM) with an asphaltic crude oil can destabilize asphaltenes and make cores less water-wet. Wetting changes can also occur due to contact with the surfactants used in SBM formulations to emulsify water and make the rock cuttings oil-wet. Reservoir cores drilled with SBMs, therefore, show wetting properties much different from the reservoir wetting conditions, invalidating laboratory core analysis using SBM contaminated cores. Core cleaning is required in order to remove all the drilling mud contaminants. In theory, core wettability can then be restored to reservoir wetting conditions by exposure to brine and crude oil. The efficiency of core cleaning of SBM contaminated cores has been explored in this study. A new core cleaning procedure was developed aimed to remove the adsorbed asphaltenes and emulsifiers from the contaminated Berea sandstone cores. Sodium hydroxide was introduced into the cleaning process in order to create a strongly alkaline condition. The high pH environment in the pore spaces changed the electrical charges of both basic and acidic functional groups, reducing the attractive interactions between adsorbing materials and the rock surface. In cores, flow-through and extraction methods were investigated. The effectiveness of the cleaning procedure was assessed by spontaneous imbibition tests and Amott wettability measurements. Test results indicating that introduction of sodium hydroxide played a key role in removing adsorbed materials were confirmed by contact angle measurements on similarly treated mica surfaces. Cleaning of the contaminated cores reversed their wettability from oil-wet to strongly water-wet as demonstrated by spontaneous

  16. Quantitative and qualitative analysis of bioactive components present in virgin coconut oil

    Directory of Open Access Journals (Sweden)

    Yashi Srivastava

    2016-12-01

    Full Text Available The hot and cold extracted virgin coconut oil (VCO has been subjected to the various quality parameters. There was a no significant difference in iodine value, saponification value, refractive index, fatty acid profile, specific gravity, and moisture content of hot extracted virgin coconut oil (HEVCO, cold extracted virgin coconut oil (CEVCO, and copra oil (CCO samples. The phenolic components of the HEVCO, CEVCO, and CCO were found to be 650.35 ± 25.11 μg/g, 401.23 ± 20.11 μg/g, and 182.82 ± 15.24 μg/g, respectively. The antioxidant activity ranged from 80 to 87% in HEVCO, 65 to 70% in CEVCO, and 35 to 45% in CCO. The results showed that VCO obtained from hot extraction process contained more total polyphenol, antioxidant activity, tocopherol, phytosterol, monoglycerides, and diglyceride content in comparison to CEVCO and CCO samples.

  17. Identification of predominant aroma components of raw, dry roasted and oil roasted almonds.

    Science.gov (United States)

    Erten, Edibe S; Cadwallader, Keith R

    2017-02-15

    Volatile components of raw, dry roasted and oil roasted almonds were isolated by solvent extraction/solvent-assisted flavor evaporation and predominant aroma compounds identified by gas chromatography-olfactometry (GCO) and aroma extract dilutions analysis (AEDA). Selected odorants were quantitated by GC-mass spectrometry and odor-activity values (OAVs) determined. Results of AEDA indicated that 1-octen-3-one and acetic acid were important aroma compounds in raw almonds. Those predominant in dry roasted almonds were methional, 2- and 3-methylbutanal, 2-acetyl-1-pyrroline and 2,3-pentanedione; whereas, in oil roasted almonds 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 2,3-pentanedione, methional and 2-acetyl-1-pyrroline were the predominant aroma compounds. Overall, oil roasted almonds contained a greater number and higher abundance of aroma compounds than either raw or dry roasted almonds. The results of this study demonstrate the importance of lipid-derived volatile compounds in raw almond aroma. Meanwhile, in dry and oil roasted almonds, the predominant aroma compounds were derived via the Maillard reaction, lipid degradation/oxidation and sugar degradation.

  18. Palm oil based surfactant products for petroleum industry

    Science.gov (United States)

    Permadi, P.; Fitria, R.; Hambali, E.

    2017-05-01

    In petroleum production process, many problems causing reduced production are found. These include limited oil recovery, wax deposit, asphaltene deposit, sludge deposit, and emulsion problem. Petroleum-based surfactant has been used to overcome these problems. Therefore, innovation to solve these problems using surfactant containing natural materials deserves to be developed. Palm oil-based surfactant is one of the potential alternatives for this. Various types of derivative products of palm oil-based surfactant have been developed by SBRC IPB to be used in handling problems including surfactant flooding, well stimulation, asphaltene dissolver, well cleaning, and wax removal found in oil and gas industry.

  19. Effect of Alkali on Daqing Crude Oil/Water Interfacial Properties

    Institute of Scientific and Technical Information of China (English)

    Guo Jixiang; Li Mingyuan; Lin Meiqin; Wu Zhaoliang

    2007-01-01

    Alkaline-surfactant-polymer (ASP) flooding using sodium hydroxide as the alkali component to enhance oil recovery in Daqing Oilfield,northeast China has been successful,but there are new problems in the treatment of produced crude. The alkali added forms stable water-in-crude oil emulsion,hence de-emulsification process is necessary to separate oil and water. The problems in enhanced oil recovery with ASP flooding were investigated in laboratory by using fractions of Daqing crude oil. The oil was separated into aliphatics,aromatics,resin and asphaltene fractions. These fractions were then mixed with an additive-free jet fuel to form model oils. The interfacial properties,such as interfacial tension and interfacial pressure of the systems were also measured,which together with the molecular parameters of the fractions were all used to investigate the problems in the enhanced oil recovery. In our work,it was found that sodium hydroxide solution reacts with the acidic hydrogen in the fractions of crude oil and forms soap-like interfacially active components,which accumulate at the crude oil-water interface.

  20. Method for determining asphaltene stability of a hydrocarbon-containing material

    Science.gov (United States)

    Schabron, John F; Rovani, Jr., Joseph F

    2013-02-05

    A method for determining asphaltene stability in a hydrocarbon-containing material having solvated asphaltenes therein is disclosed. In at least one embodiment, it involves the steps of: (a) precipitating an amount of the asphaltenes from a liquid sample of the hydrocarbon-containing material with an alkane mobile phase solvent in a column; (b) dissolving a first amount and a second amount of the precipitated asphaltenes by changing the alkane mobile phase solvent to a final mobile phase solvent having a solubility parameter that is higher than the alkane mobile phase solvent; (c) monitoring the concentration of eluted fractions from the column; (d) creating a solubility profile of the dissolved asphaltenes in the hydrocarbon-containing material; and (e) determining one or more asphaltene stability parameters of the hydrocarbon-containing material.

  1. High-oleic sunflower, a new oil component; Die High-Oleic-Sunflower als neue Grundoelkomponente

    Energy Technology Data Exchange (ETDEWEB)

    Botz, O. [Natoil AG, Technopark Luzern (Switzerland)

    2007-07-01

    Achieved results from NATOIL {sup registered} proved that the application of the High-Oleic-Sunflower as a component of a base oil in lubricants is in general feasible. The target goals and properties have been realised with great success. To emphasize are particularly good results in relation to piston cleanliness, oxidative stability as well as fuel economy properties. The central fear that the High-Oleic-Sunflower would not be sufficiently stable concerning oxidation has been clearly refuted in diverse motor tests. The application of the High-Oleic Sunflower and of the here of manufactured esters enables the development of lubricants with much lower viscosity characteristics in comparison to mineral-oil-based lubricants, which may result in the overall reduction of the average drag torque by up to 30%. (orig.)

  2. WETTABILITY AND PREDICTION OF OIL RECOVERY FROM RESERVOIRS DEVELOPED WITH MODERN DRILLING AND COMPLETION FLUIDS

    Energy Technology Data Exchange (ETDEWEB)

    Jill S. Buckley; Norman R. Morrow

    2004-05-01

    We report on progress in three areas. In part one, the wetting effects of synthetic base oils are reported. Part two reports progress in understanding the effects of surfactants of known chemical structures, and part three integrates the results from surface and core tests that show the wetting effects of commercial surfactant products used in synthetic and traditional oil-based drilling fluids. An important difference between synthetic and traditional oil-based muds (SBM and OBM, respectively) is the elimination of aromatics from the base oil to meet environmental regulations. The base oils used include dearomatized mineral oils, linear alpha-olefins, internal olefins, and esters. We show in part one that all of these materials except the esters can, at sufficiently high concentrations, destabilize asphaltenes. The effects of asphaltenes on wetting are in part related to their stability. Although asphaltenes have some tendency to adsorb on solid surfaces from a good solvent, that tendency can be much increased near the onset of asphaltene instability. Tests in Berea sandstone cores demonstrate wetting alteration toward less water-wet conditions that occurs when a crude oil is displaced by paraffinic and olefinic SBM base oils, whereas exposure to the ester products has little effect on wetting properties of the cores. Microscopic observations with atomic forces microscopy (AFM) and macroscopic contact angle measurements have been used in part 2 to explore the effects on wetting of mica surfaces using oil-soluble polyethoxylated amine surfactants with varying hydrocarbon chain lengths and extent of ethoxylation. In the absence of water, only weak adsorption occurs. Much stronger, pH-dependent adsorption was observed when water was present. Varying hydrocarbon chain length had little or no effect on adsorption, whereas varying extent of ethoxylation had a much more significant impact, reducing contact angles at nearly all conditions tested. Preequilibration of

  3. Enantioselective GC-MS analysis of volatile components from rosemary (Rosmarinus officinalis L.) essential oils and hydrosols.

    Science.gov (United States)

    Tomi, Kenichi; Kitao, Makiko; Konishi, Norihiro; Murakami, Hiroshi; Matsumura, Yasuki; Hayashi, Takahiro

    2016-05-01

    Essential oils and hydrosols were extracted from rosemary harvested in different seasons, and the chemical compositions of volatile components in the two fractions were analyzed by gas chromatography-mass spectrometry (GC-MS). Enantiomers of some volatile components were also analyzed by enantioselective GC-MS. Classification of aroma components based on chemical groups revealed that essential oils contained high levels of monoterpene hydrocarbons but hydrosols did not. Furthermore, the enantiomeric ratios within some volatile components were different from each other; for example, only the (S)-form was observed for limonene and the (R)-form was dominant for verbenone. These indicate the importance of determining the enantiomer composition of volatile components for investigating the physiological and psychological effects on humans. Overall, enantiomeric ratios were determined by volatile components, with no difference between essential oils and hydrosols or between seasons.

  4. Effect of biosurfactants on crude oil desorption and mobilization in a soil system

    Energy Technology Data Exchange (ETDEWEB)

    Kuyukina, M.S.; Ivshina, I.B. [Ural Branch of the Russian Academy of Sciences, Perm (Russian Federation). Institute of Ecology and Genetics of Microorganisms; Makarov, S.O.; Litvinenko, L.V. [Perm State University, Perm (Russian Federation); Cunningham, C.J. [University of Edinburgh (United Kingdom). Contaminated Land Assessment and Remediation Research Centre; Philp, J.C. [Napier University, Edinburgh (United Kingdom). School of Life Sciences

    2005-02-01

    Microbially produced biosurfactants were studied to enhance crude oil desorption and mobilization in model soil column systems. The ability of biosurfactants from Rhodococcus ruber to remove the oil from the soil core was 1.4-2.3 times greater than that of a synthetic surfactant of suitable properties, Tween 60. Biosurfactant-enhanced oil mobilization was temperature-related, and it was slower at 15{sup o}C than at 22-28{sup o}C. Mathematical modelling using a one-dimensional filtration model was applied to simulate the process of oil penetration through a soil column in the presence of (bio)surfactants. A strong positive correlation (R{sup 2} = 0.99) was found between surfactant penetration through oil-contaminated soil and oil removal activity. Biosurfactant was less adsorbed to soil components than synthetic surfactant, thus rapidly penetrating through the soil column and effectively removing 65-82% of crude oil. Chemical analysis showed that crude oil removed by biosurfactant contained a lower proportion of high-molecular-weight paraffins and asphaltenes, the most nonbiodegradable compounds, compared to initial oil composition. This result suggests that oil mobilized by biosurfactants could be easily biodegraded by soil bacteria. Rhodococcus biosurfactants can be used for in situ remediation of oil-contaminated soils. (author)

  5. Chemical structure of asphaltenes of tar semicoked from Kansk-Achinsk lignite

    Energy Technology Data Exchange (ETDEWEB)

    Platanov, V.V.; Proskuryakov, V.A.; Klyavina, O.A. [Ln Tolstoi Tula State Pedagogical Institute, Tula (Russian Federation)

    1994-03-01

    The chemical structure has been studied of asphaltenes of tar semicoked from Kansk-Achinsk lignite and recovered at a temperature less than or equal to 350{degree}C. Asphaltenes have been found to be a complete mixture of aromatic, alicyclic, hydroaromatic, and heterocyclic compounds substituted by alkyl chains and various functional groups. A number of asphaltene compounds originate from steroids and triterpanes, which widely occur in lipid and tar fractions of plants and in the metabolites of microbes. A procedure based on adsorptive liquid chromatography has been developed to separate asphaltenes into a great number of eluates with considerably differing structural parameters and functional compositions.

  6. RELATIONSHIP BETWEEN DIFFERENT BUSINESS VALUE COMPONENTS WITHIN THE OIL AND GAS INDUSTRY

    Directory of Open Access Journals (Sweden)

    Sonja Brlečić Valčić

    2016-07-01

    Full Text Available The oil and gas industry is characterized by many complexities and specificities of business operations. The above is also reflected in the identification of value components, and the understanding of their interrelationships. In order to have an effective value management, it is especially important to follow up on the movements in key financial indicators and qualitative factors which impact the creation of financial results. This paper presents the theoretical basis in order to identify the most important qualitative value components in oil and gas companies. Therefore, the specificities of all sectors within this industry are highlighted in order for them to be related to the key financial factors influencing the creation of stable cash flows. For this purpose, a cluster analysis of selected key financial factors has been performed using self-organizing neural networks. Connecting identified qualitative value components affecting cash flows with the financial parameters through which they are reflected, creates a framework for developing an effective value management model.

  7. Comparative analysis of antioxidant activities of fourteen mentha essential oils and their components.

    Science.gov (United States)

    Sitzmann, Judith; Habegger, Ruth; Schnitzler, Wilfried H; Grassmann, Johanna

    2014-12-01

    The essential oils of 14 species and hybrids, respectively, of the genus Mentha were examined for their antioxidant capacity in the ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)) assay and in a lipid-peroxidation (LPO) assay. The ABTS(.+) -scavenging capacity of pure essential-oil components and mixtures of them was also tested. In both assays, Mentha×dumetorum (classification not fully confirmed), Mentha suaveolens, and Mentha×villosa (classification not fully confirmed) showed the highest antioxidant capacity, which was ascribed to the components germacrene D, piperitone oxide, and piperitenone oxide. The high antioxidant activity in the LPO assay of the two hybrids Mentha×gracilis and, to a lower degree, of Mentha×dalmatica (classification not fully confirmed) was ascribed to their high contents of cis-ocimene and β-caryophyllene. Of the pure components tested (germacrene D, piperitone oxide, and piperitenone oxide were not tested, as not commercially available), only cis-ocimene showed a distinct antioxidant effect, whereas dihydrocarvone and linalool had pro-oxidant effects in the ABTS assay.

  8. Effect of Contact Time and Gas Component on Interfacial Tension of CO2/Crude Oil System by Pendant Drop Method

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2015-01-01

    Full Text Available Pendant drop method has been used to measure the equilibrium interfacial tension and dynamic interfacial tension of CO2/crude oil system under the simulated-formation condition, in which the temperature is 355.65 K and pressure ranges from 0 MPa to 30 MPa. The test results indicated that the equilibrium interfacial tension of CO2/crude oil systems decreased with the increase of the systematic pressure. The dynamic interfacial tension of CO2/original oil, CO2/remaining oil, and CO2/produced oil systems is large at the initial contact and decreases gradually after that, and then finally it reaches dynamic balance. In addition, the higher the pressure is, the larger the magnitude of changing of CO2/crude oil interfacial tension with time will reduce. Moreover, by PVT phase experiment, gas-oil ratio, gas composition, and well fluid composition have been got, and different contents of light components in three oil samples under reservoir conditions have also been calculated. The relationship between equilibrium interfacial tensions and pressures of three different components of crude oil and CO2 system was studied, and the higher C1 is, the lower C2–C10 will be, and the equilibrium interfacial tension will get higher. Therefore, the effect of light weight fractions on interfacial tension under formation conditions was studied.

  9. Trends in Edible Vegetable Oils Analysis. Part A. Determination of Different Components of Edible Oils - a Review

    National Research Council Canada - National Science Library

    Gromadzka, Justyna; Wardencki, Waldemar

    2011-01-01

    This review presents recent approaches applied to analysis of edible oils. In the last decade increasing attention has been paid to human diet concerning also edible oils and fats as a source of healthy energy...

  10. Day-Ahead Crude Oil Price Forecasting Using a Novel Morphological Component Analysis Based Model

    Science.gov (United States)

    Zhu, Qing; Zou, Yingchao; Lai, Kin Keung

    2014-01-01

    As a typical nonlinear and dynamic system, the crude oil price movement is difficult to predict and its accurate forecasting remains the subject of intense research activity. Recent empirical evidence suggests that the multiscale data characteristics in the price movement are another important stylized fact. The incorporation of mixture of data characteristics in the time scale domain during the modelling process can lead to significant performance improvement. This paper proposes a novel morphological component analysis based hybrid methodology for modeling the multiscale heterogeneous characteristics of the price movement in the crude oil markets. Empirical studies in two representative benchmark crude oil markets reveal the existence of multiscale heterogeneous microdata structure. The significant performance improvement of the proposed algorithm incorporating the heterogeneous data characteristics, against benchmark random walk, ARMA, and SVR models, is also attributed to the innovative methodology proposed to incorporate this important stylized fact during the modelling process. Meanwhile, work in this paper offers additional insights into the heterogeneous market microstructure with economic viable interpretations. PMID:25061614

  11. Day-ahead crude oil price forecasting using a novel morphological component analysis based model.

    Science.gov (United States)

    Zhu, Qing; He, Kaijian; Zou, Yingchao; Lai, Kin Keung

    2014-01-01

    As a typical nonlinear and dynamic system, the crude oil price movement is difficult to predict and its accurate forecasting remains the subject of intense research activity. Recent empirical evidence suggests that the multiscale data characteristics in the price movement are another important stylized fact. The incorporation of mixture of data characteristics in the time scale domain during the modelling process can lead to significant performance improvement. This paper proposes a novel morphological component analysis based hybrid methodology for modeling the multiscale heterogeneous characteristics of the price movement in the crude oil markets. Empirical studies in two representative benchmark crude oil markets reveal the existence of multiscale heterogeneous microdata structure. The significant performance improvement of the proposed algorithm incorporating the heterogeneous data characteristics, against benchmark random walk, ARMA, and SVR models, is also attributed to the innovative methodology proposed to incorporate this important stylized fact during the modelling process. Meanwhile, work in this paper offers additional insights into the heterogeneous market microstructure with economic viable interpretations.

  12. GC-MS analysis of essential oils from Salvia officinalis L.: comparison of extraction methods of the volatile components.

    Science.gov (United States)

    Baj, Tomasz; Ludwiczuk, Agnieszka; Sieniawska, Elwira; Skalicka-Woźniak, Krystyna; Widelski, Jarosław; Zieba, Krzysztof; Głowniak, Kazimierz

    2013-01-01

    In this paper, comparison of the volatile components composition in the samples obtained by hydrodistillation and solid-phase microextraction of Salvia officinalis was described. Different sample preparation techniques showed considerable differences in volatiles composition, especially with respect to sesqui- and diterpenoids. The comparison of the sage essential oil obtained by hydrodistillation in the Deryng and Clevenger type apparatus, according to the pharmacopoeial methods (FP VI and VII), showed the presence of the same terpenoids in both essential oils, however, the relative percentage composition of the components were different. These differences are caused by the different extraction times used in both methods. Since each essential oil to be admitted to medicinal use should meet requirements regarding the composition of major chemical components, the minimum time for the hydrodistillation of the essential oils from sage should be 1 h.

  13. Characterization of volatile components and odor-active compounds in the oil of edible mushroom Boletopsis leucomelas.

    Science.gov (United States)

    Nosaka, Sota; Miyazawa, Mitsuo

    2014-01-01

    The volatile oil from Boletopsis leucomelas (Pers.) Fayod was extracted by hydrodistillation with diethylether, and the volatile components of the oil were analyzed by gas chromatography-mass spectrometry. The oil contained 86 components, representing 87.5% of the total oil. The main components of the oil were linoleic acid (15.0%), phenylacetaldehyde (11.2%), and palmitic acid (9.4%). Furthermore, sulfur-containing compounds including 3-thiophenecarboxaldehyde, 2-acetylthiazole, S-methyl methanethiosulfonate, and benzothiazole were detected using gas chromatography-pulsed flame photometric detection. The odor components were evaluated by the odor activity value, and aroma extract dilution analysis was performed through gas chromatography-olfactometry analysis. The oil had a mushroom-like, fatty, and burnt odor. The main components contributing to the mushroom-like and fatty odor were hexanal, nonanal, 1-octen-3-ol, and (2E)-nonenal, while the burnt odor was due to furfuryl alcohol, benzaldehyde, 5-methyl furfural, 2,3,5-trimethylpyrazine, 2-acethylthiazole, and indole.

  14. Identification and quantification of the antimicrobial components of a citrus essential oil vapor.

    Science.gov (United States)

    Phillips, Carol A; Gkatzionis, Konstantinos; Laird, Katie; Score, Jodie; Kant, Avinash; Fielder, Mark D

    2012-01-01

    The anti-bacterial components of a citrus essential oil vapor were identified as linalool, citral and beta-pinene using a bioautography method and quantified by GC-MS. Essential oil vapor release, monitored in real-time with Atmospheric Pressure Chemical Ionization - MS (APCI-MS), showed differences in the vapor release profile oflimonene, beta-pinene and linalool over 24 hours, while Solid Phase Micro-extraction (SPME) GC-MS demonstrated changes in composition of the vapor at 35 degrees C. Fourteen isolates were tested in vitro for their susceptibility to the EO vapor and to linalool, citral and beta-pinene vapors, both separately and in a mixture containing the three components in the amounts at which they occur in the EO vapor. All eleven Gram-positive strains tested were susceptible to the EO vapor, linalool, citral and beta-pinene vapors separately and the mixture with zones of inhibition of 4.34 cm, 5.32 cm, 5.58 cm, 4.86 cm and 4.68 cm, respectively. Of the three Gram-negative strains tested, Pseudomonas aeruginosa 10145 was resistant to all the vapors. When bacteria inoculated onto stainless steel surfaces were exposed to either the EO vapor or a linalool/citral/beta-pinene vapor mixture there was no significant difference in reduction for the Gram-positive isolates, while the Gram-negative isolates were resistant to both EO vapor and the linalool/citral/beta-pinene mixture.

  15. In vitro control of post-harvest fruit rot fungi by some plant essential oil components.

    Science.gov (United States)

    Camele, Ippolito; Altieri, Luciana; De Martino, Laura; De Feo, Vincenzo; Mancini, Emilia; Rana, Gian Luigi

    2012-01-01

    Eight substances that are main components of the essential oils from three Mediterranean aromatic plants (Verbena officinalis, Thymus vulgaris and Origanum vulgare), previously found active against some phytopathogenic Fungi and Stramenopila, have been tested in vitro against five etiological agents of post-harvest fruit decay, Botrytis cinerea, Penicillium italicum, P. expansum, Phytophthora citrophthora and Rhizopus stolonifer. The tested compounds were β-fellandrene, β-pinene, camphene, carvacrol, citral, o-cymene, γ-terpinene and thymol. Citral exhibited a fungicidal action against P. citrophthora; carvacrol and thymol showed a fungistatic activity against P. citrophthora and R. stolonifer. Citral and carvacrol at 250 ppm, and thymol at 150 and 250 ppm stopped the growth of B. cinerea. Moreover, thymol showed fungistatic and fungicidal action against P. italicum. Finally, the mycelium growth of P. expansum was inhibited in the presence of 250 ppm of thymol and carvacrol. These results represent an important step toward the goal to use some essential oils or their components as natural preservatives for fruits and foodstuffs, due to their safety for consumer healthy and positive effect on shelf life extension of agricultural fresh products.

  16. Radiosensitivity on the components of essential oil in the genus Mentha

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Seiroku (Okayama Univ. (Japan). Faculty of Agriculture)

    1992-10-01

    The effects of seed irradiation using X-rays (20KR) on the components of the essential oil in the adult plant were investigated using Mentha arvensis L. var. piperascens Malinvaud (2n=96). 1. X-ray irradiation produced almost no effect on the dry matter weight and content of essential oil at any stage of growth. 2. Using X-ray irradiation, the level of free menthol was increased, and ester menthol and menthone were decreased. This seemed to suggest that menthol was synthesized by the reduction of the menthone. 3. The content of free menthol was found to increase linearly toward leaves of the upper level, while the content of menthone was found to gradually decrease and, finally, to disappear in leaves at fifth level of leaves. 4. No difference was found in the ratios of contents of inorganic component between the first and second harvest seasons. There was also no difference in the content of total nitrogen at any location of leaves, except when an increased concentration of nitrogen at the seventh level of leaves was found. (author).

  17. In Vitro Control of Post-Harvest Fruit Rot Fungi by Some Plant Essential Oil Components

    Directory of Open Access Journals (Sweden)

    Gian Luigi Rana

    2012-02-01

    Full Text Available Eight substances that are main components of the essential oils from three Mediterranean aromatic plants (Verbena officinalis, Thymus vulgaris and Origanum vulgare, previously found active against some phytopathogenic Fungi and Stramenopila, have been tested in vitro against five etiological agents of post-harvest fruit decay, Botrytis cinerea, Penicillium italicum, P. expansum, Phytophthora citrophthora and Rhizopus stolonifer. The tested compounds were β-fellandrene, β-pinene, camphene, carvacrol, citral, o-cymene, γ-terpinene and thymol. Citral exhibited a fungicidal action against P. citrophthora; carvacrol and thymol showed a fungistatic activity against P. citrophthora and R. stolonifer. Citral and carvacrol at 250 ppm, and thymol at 150 and 250 ppm stopped the growth of B. cinerea. Moreover, thymol showed fungistatic and fungicidal action against P. italicum. Finally, the mycelium growth of P. expansum was inhibited in the presence of 250 ppm of thymol and carvacrol. These results represent an important step toward the goal to use some essential oils or their components as natural preservatives for fruits and foodstuffs, due to their safety for consumer healthy and positive effect on shelf life extension of agricultural fresh products.

  18. A new methodology capable of characterizing most volatile and less volatile minor edible oils components in a single chromatographic run without solvents or reagents. Detection of new components.

    Science.gov (United States)

    Alberdi-Cedeño, Jon; Ibargoitia, María L; Cristillo, Giovanna; Sopelana, Patricia; Guillén, María D

    2017-04-15

    The possibilities offered by a new methodology to determine minor components in edible oils are described. This is based on immersion of a solid-phase microextraction fiber of PDMS/DVB into the oil matrix, followed by Gas Chromatography/Mass Spectrometry. It enables characterization and differentiation of edible oils in a simple way, without either solvents or sample modification. This methodology allows simultaneous identification and quantification of sterols, tocols, hydrocarbons of different natures, fatty acids, esters, monoglycerides, fatty amides, aldehydes, ketones, alcohols, epoxides, furans, pyrans and terpenic oxygenated derivatives. The broad information provided by this methodology is useful for different areas of interest such as nutritional value, oxidative stability, technological performance, quality, processing, safety and even the prevention of fraudulent practices. Furthermore, for the first time, certain fatty amides, gamma- and delta-lactones of high molecular weight, and other aromatic compounds such as some esters derived from cinnamic acid have been detected in edible oils.

  19. Biodegradation of heavy oils by halophilic bacterium

    Institute of Scientific and Technical Information of China (English)

    Ruixia Hao; Anhuai Lu

    2009-01-01

    A halophilic bacterial strain TM-1 was isolated from the reservoir of the Shengli oil field in East China. Strain TM-1, which was found to be able to degrade crude oils, is a gram-positive non-motile bacterium with a coccus shape that can grow at temperatures of up to 58 ℃ and in 18% NaCl solution. Depending on the culture conditions, the organism may occur in tetrads. In addition, strain TM-1 pro-duced acid from glucose without gas formation and was catalase-negative. Furthermore, strain TM-I was found to be a facultative aer-obe capable of growth under anaerobic conditions. Moreover, it produced butylated hydroxytoluene, 1,2-benzenedicarboxylic acid-bis ester and dibutyl phthalate and could use different organic substrates. Laboratory studies indicated that strain TM-1 affected different heavy oils by degrading various components and by changing the chemical properties of the oils. In addition, growth of the bacterium in heavy oils resulted in the loss of aromatic hydrocarbons, resins and asphaltenes, and enrichment with light hydrocarbons and an overall redistribution of these hydrocarbons.

  20. Effect of micella interesterification on fatty acids composition and volatile components of soybean and rapeseed oils

    Directory of Open Access Journals (Sweden)

    Afifi, Sherine M.

    2000-10-01

    Full Text Available Micella interesterification of soybean and rapeseed oils was carried out using 0.2, 0.4 and 0.6 percentages of nickel catalyst, each at different temperatures of 60, 90 and 120ºC for 2, 4, and 6 hours. The proposed interesterification reaction conditions to obtain an oil with low linoleic acid level were 0.2 % nickel catalyst at 120ºC for 4 hours, 0.4% nickel catalyst at 90ºC for 4 hours and 0.6% at 60ºC for 4 hours. Fatty acid composition and chemical analysis of the interesterified and non-esterified oils were estimated. Selected samples undergo heating at 180ºC for 4 hours determining the volatile components. The appearance of some components supported the interesterification process for modification of fatty acid constituents of the oils.Se ha llevado a cabo la interesterificación en fase miscelar de aceites de soja y de colza usando un 0.2%, 0.4% y 0.6% de níquel como catalizador, a diferentes temperaturas (60, 90 y 120ºC durante 2, 4 y 6 horas. Las condiciones de reacción de interesterificación propuestas para obtener un aceite con niveles de ácidos linolénicos bajos fueron 0.2 % de níquel a 120ºC durante 4 horas, 0.4 % de níquel a 90ºC durante 4 horas y 0.6 % a 60ºC durante 4 horas. Se han estimado la composición en ácidos grasos y el análisis químico de los aceites interesterificados y no-esterificados. Las muestras seleccionadas se sometieron a calentamiento a 180ºC durante 4 horas determinando los componentes volátiles. La aparición de algunos componentes apoyó el proceso de interesterificación por modificación de los ácidos grasos constituyentes de los aceites.

  1. Asphaltene self-association: Modeling and effect of fractionation with a polar solvent

    DEFF Research Database (Denmark)

    Garcia, Daniel Merino; Murgich, J; Andersen, Simon Ivar

    2004-01-01

    The self-association of asphaltenes in toluene is believed to occur step-wise, rather than by the formation of micelles. A number of step-wise models have been used to fit the calorimetric titration of asphaltenes in dried toluene solutions, with excellent results. All the models are based on che...

  2. Impact of maltene and asphaltene fraction on mechanical behavior and microstructure of bitumen

    NARCIS (Netherlands)

    Hofko, B.; Eberhardsteiner, L.; Fussl, J.; Grothe, H.; Handle, F.; Hospodka, M.; Grossegger, D.; Nahar, S.N.; Schmets, A.J.M.; Scarpas, A.

    2015-01-01

    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

  3. THE STUDY OF THE STRUCTURAL CHARACTERISTICS AND RHEOLOGICAL PROPERTIES OF OIL AND THE SOUTH -INZYREYSKOGO USINSK DEPOSIT

    Directory of Open Access Journals (Sweden)

    Shiryaeva R.N.

    2013-03-01

    Full Text Available By means of IR-spectrometry general structural fragments of high-viscous oils resins and asphaltenes isolated from oils are stadied. It was determined that differ significantly on content alkil, hydroxide and carbonil groups. Developed reagent OKN allows to improve significantly reological deseription of South- Inzyreyskoy and Usinsk oil and may be recommended for use in oil industry

  4. Géochimie des résines et asphaltènes Geochernistry of Resins and Asphaltenes

    Directory of Open Access Journals (Sweden)

    Tissot B.

    2006-11-01

    Full Text Available Les produits lourds des huiles brutes (résines et asphaltènes jouent un rôle important dans la genèse et l'accumulation du pétrole, ainsi que dans la mise en production par des méthodes conventionnelles ou par récupération assistée. Les asphaltènes et résines sont considérés ici comme des fragments de kérogène, avec une structure d'ensemble comparable : ils peuvent constituer des intermédiaires dans la genèse de l'huile brute par dégradation thermique du kérogène. De plus, la pyrolyse des asphaltènes séparés à partir d'un pétrole biodégradé peut produire de nouveaux hydrocarbures saturés qui reproduisent la fraction saturée primitive, détruite par la dégradation ; on peut ainsi disposer d'un nouvel outil pour corréler ce type d'huiles brutes. Les produits lourds semblent défavorisés par rapport aux hydrocarbures, dans la migration de la roche-mère vers le réservoir, où les résines et asphaltènes sont proportionnellement moins abondants. La structure physique des asphaltènes et résines dans les pétroles, et en particulier l'existence d'une macrostructure du type micelles ou agrégats, est probablement responsable de la viscosité élevée des huiles lourdes. Une meilleure connaissance de cette macrostructure pourrait suggérer de nouvelles méthodes pour diminuer la viscosité et améliorer la récupération des huiles lourdes. The heavy constituents of crude oil (resins and asphaltenes play an important role in generation and accumulation of petroleum, and also in production by conventional and enhanced oil recovery processes. Asphaltenes and resins are considered here as small fragments of kerogen, with a comparable overall structure: they may act as intermediate compounds in oil generation by thermal breakdown of kerogen. Furthermore, pyrolysis of asphaltenes separated from a degraded crude oil is able to generate a new saturated hydrocarbon fraction which duplicates the original one, now degraded

  5. Coupled extruder-headspace, a new method for analysis of the essential oil components of Coriandrum sativum fruits.

    Science.gov (United States)

    Sriti, Jazia; Msaada, Kamel; Talou, Thierry; Faye, Mamadou; Vilarem, Gerard; Marzouk, Brahim

    2012-10-15

    A new method involving concurrent single screw extruder combined with continuous headspace dynamic for the extraction and identification of the essential oil of Coriandrum sativum L. fruit was developed. The effect of six different nozzle diameters (5, 6, 7, 8, 9 and 10 mm) on the content and chemical composition of the essential oil of coriander fruit was studied. The oils from fruit samples were obtained by OMEGA 20 extruder. The result showed that the highest yield (0.53%) was obtained by the diameter of the nozzle was 8mm. Twenty-nine components were determined in essential oils, which were mostly hydrocarbons and alcohol monoterpenes. The main components linalool, α-pinene, γ-terpinene, p-cymene and limonene showed significant variations with drying trials.

  6. Effect of extra virgin olive oil components on the arachidonic acid cascade, colorectal cancer and colon cancer cell proliferation

    Directory of Open Access Journals (Sweden)

    C. E. Storniolo

    2016-12-01

    Full Text Available The mediterranean diet (MD reduced the risk of colorectal cancer (CRC, and olive oil, the primary source of fat in the MD, has also been found to have a protective effect. However, animals fed with oleic acid present a high number of intestinal tumours, suggesting that oleic acid and olive oil consumption can exert different effects on CRC. Considering that extra virgin olive oil (EVOO is a complex mix of fatty acids and minor compounds such as polyphenols, hydrocarbons, phytosterols and triterpenes; and that these compounds have antioxidant activity and consequently they can modulate the arachidonic acid (AA cascade and eicosanoid synthesis. This review analyzes the state of the art of olive oil components on the AA cascade and cellular mechanism involved in CRC such as intestinal epithelial cell growth/apoptosis, to understand the fact that the consumption of seed oils with high oleic content or EVOO will probably have different effects on CRC development.

  7. Extraction of essential oil from shaddock peel and analysis of its components by gas chromatography-mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Essential oil, with more than thirty kinds of compounds separated and identified by gas chromatographymass spectrometry, was extracted from Shatian shaddock peel and Sweet shaddock peel by squeeze-steam distillation and direct steam distillation method. Among their composition, the main components are terpene compounds, which account for 93. 926% (mass fraction, the same below) and 85. 843% of essential oils extracted from Shatian shaddock peel and Sweet shaddock peel, respectively. Although nootkatone is the major contributor of shaddock characteristic scent, and its contents are 1. 069 % and 1. 749 % of essential oils from Sweet shaddock peel and Shatian shaddock peel, respectively. The results show that squeeze-steam distillation gives higher yield and good quality of essential oil and the compositions of essential oils from two kinds of shaddock peels are different, but the main contributors of the shaddock scent are the same.

  8. First evidence of mineralization of petroleum asphaltenes by a strain of Neosartorya fischeri

    Science.gov (United States)

    Uribe‐Alvarez, Cristina; Ayala, Marcela; Perezgasga, Lucia; Naranjo, Leopoldo; Urbina, Héctor; Vazquez‐Duhalt, Rafael

    2011-01-01

    Summary A fungal strain isolated from a microbial consortium growing in a natural asphalt lake is able to grow in purified asphaltenes as the only source of carbon and energy. The asphaltenes were rigorously purified in order to avoid contamination from other petroleum fractions. In addition, most of petroporphyrins were removed. The 18S rRNA and β‐tubulin genomic sequences, as well as some morphologic characteristics, indicate that the isolate is Neosartorya fischeri. After 11 weeks of growth, the fungus is able to metabolize 15.5% of the asphaltenic carbon, including 13.2% transformed to CO2. In a medium containing asphaltenes as the sole source of carbon and energy, the fungal isolate produces extracellular laccase activity, which is not detected when the fungus grow in a rich medium. The results obtained in this work clearly demonstrate that there are microorganisms able to metabolize and mineralize asphaltenes, which is considered the most recalcitrant petroleum fraction. PMID:21624102

  9. Far- and mid-infrared spectroscopy of complex organic matter of astrochemical interest: coal, heavy petroleum fractions, and asphaltenes

    CERN Document Server

    Cataldo, F; Manchado, A

    2012-01-01

    The coexistence of a large variety of molecular species (i.e., aromatic, cycloaliphatic and aliphatic) in several astrophysical environments suggests that unidentified IR emission (UIE) occurs from small solid particles containing a mix of aromatic and aliphatic structures (e.g., coal, petroleum, etc.), renewing the astronomical interest on this type of materials. A series of heavy petroleum fractions namely DAE, RAE, BQ-1, and asphaltenes derived from BQ-1 were used together with anthracite coal and bitumen as model compounds in matching the band pattern of the emission features of proto-planetary nebulae (PPNe). All the model materials were examined in the mid-infrared (2.5-16.7 um) and for the first time in the far-infrared (16.7-200 um), and the IR bands were compared with the UIE from PPNe. The best match of the PPNe band pattern is offered by the BQ-1 heavy aromatic oil fraction and by its asphaltenes fraction. Particularly interesting is the ability of BQ-1 to match the band pattern of the aromatic-ali...

  10. Thymus vulgaris L. essential oil and its main component thymol: Anthelmintic effects against Haemonchus contortus from sheep.

    Science.gov (United States)

    Ferreira, Luis E; Benincasa, Bruno I; Fachin, Ana L; França, Suzelei C; Contini, Silvia S H T; Chagas, Ana C S; Beleboni, Rene O

    2016-09-15

    Haemonchus contortus is an important gastrointestinal parasite on sheep farms in tropical regions. The resistance of the parasite against most anthelmintic drugs represents a great economic problem to sheep farming and is a major challenge that needs to be overcome. The searches for new anthelmintic agents that act on different stages of the parasite's life cycle are necessary for the development of new therapeutic options. The aim of this study was to evaluate the in vitro and in vivo anthelmintic activity of Thymus vulgaris essential oil against H. contortus and of its main component, the monoterpene thymol. Despite the relative ineffectiveness of the oil in the in vivo test, which may be corrected in the future after technical improvements to increase the oil's bioavailability, the in vitro results validated the popular use of T. vulgaris oil as an anthelmintic agent, at least against H. contortus. In fact, both the essential oil and thymol, which accounts for 50.22% of the oil composition, were effective against the three main stages of H. contortus. The oil and thymol were able to inhibit egg hatching by 96.4-100%, larval development by 90.8-100%, and larval motility by 97-100%. Similar to the positive control (levamisole 20mg/mL), the oil and thymol completely inhibited the motility of H. contortus adults within the first 8h of the experiment. Since thymol reproduces the anthelmintic effects of the oil and because it is the main component of the oil, it is reasonable to assume that thymol is the most important compound responsible for the anthelmintic effect of T. vulgaris. These results are of ethnopharmacological importance and may contribute to the development of new drugs and even herbal medicines, increasing treatment options for the farm breeding. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Quantitative analysis of multi-component complex oil spills based on the least-squares support vector regression

    Science.gov (United States)

    Tan, Ailing; Zhao, Yong; Wang, Siyuan

    2016-10-01

    Quantitative analysis of the simulated complex oil spills was researched based on PSO-LS-SVR method. Forty simulated mixture oil spills samples were made with different concentration proportions of gasoline, diesel and kerosene oil, and their near infrared spectra were collected. The parameters of least squares support vector machine were optimized by particle swarm optimization algorithm. The optimal concentration quantitative models of three-component oil spills were established. The best regularization parameter C and kernel parameter σ of gasoline, diesel and kerosene model were 48.1418 and 0.1067, 53.2820 and 0.1095, 59.1689 and 0.1000 respectively. The decision coefficient R2 of the prediction model were 0.9983, 0.9907 and 0.9942 respectively. RMSEP values were 0.0753, 0.1539 and 0.0789 respectively. For gasoline, diesel fuel and kerosene oil models, the mean value and variance value of predict absolute error were -0.0176±0.0636 μL/mL, -0.0084+/-0.1941 μL/mL, and 0.00338+/-0.0726 μL/mL respectively. The results showed that each component's concentration of the oil spills samples could be detected by the NIR technology combined with PSO-LS-SVR regression method, the predict results were accurate and reliable, thus this method can provide effective means for the quantitative detection and analysis of complex marine oil spills.

  12. Effect of (+)-pulegone and other oil components of Mentha x Piperita on cucumber respiration.

    Science.gov (United States)

    Mucciarelli, M; Camusso, W; Bertea, C M; Maffei, M

    2001-05-01

    Peppermint (Mentha x piperita L.) essential oil and main components were assessed for their ability to interfere with plant respiratory functions. Tests were conducted on both root segments and mitochondria isolated by etiolated seedlings of cucumber (Cucumis sativus L.). Total essential oil inhibited 50% of root and mitochondrial respiration (IC50) when used at 324 and 593 ppm, respectively. (+)-Pulegone was the most toxic compound, with a 0.08 and 0.12 mM IC50 for root and mitochondrial respiration, respectively. (-)-Menthone. followed (+)-pulegone in its inhibitory action (IC50 values of 1.11 and 2.30 mM for root and mitochondrial respiration respectively), whereas (-)-menthol was the less inhibitory compound (IC50 values of 1.85 and 3.80 mM respectively). A positive correlation was found for (+)-pulegone, (-)-menthone and (-)-menthol between water solubility and respiratory inhibition. The uncoupling agent. carbonyl-cyanide-m-chlorophenyl-hydrazone (CCCP), lowered (-)-menthol and (-)menthone inhibition and annulled (+)-pulegone inhibition of mitochondrial respiration, whereas salicyl-hydroxamic acid (SHAM) 2-hydroxybenzohydroxamic acid, the alternative oxidase (AO) inhibitor, increased (-)-menthone inhibition and annulled both (+)-pulegone and (-)-menthol inhibitory activity. The possible interaction of (-)-pulegone and (-)-menthol with AO and the mechanism of action of(+)-pulegone, (-)-menthone and (-)-menthol on mitochondrial respiration are discussed.

  13. Optimisation of supercritical fluid extraction of essential oil components of Diplotaenia cachrydifolia: Box-Behnken design.

    Science.gov (United States)

    Khajeh, Mostafa

    2012-01-01

    Essential oil of Diplotaenia cachrydifolia cultivated in Iran was obtained by supercritical fluid extraction (SFE) method. The oils were analysed by capillary gas chromatography using flame ionisation and mass spectrometric detections. The compounds were identified according to their retention indices and mass spectra (EI, 70 eV). The effects of different parameters, such as pressure, temperature, modifier volume and extraction times (dynamic and static), on the SFE were inspected by a fractional factorial design (2(5-2)) to identify the significant parameters and their interaction. It showed that static and dynamic times had no effect on the extraction. Finally, a Box-Behnken design was applied to obtain the optimum condition of the significant parameters. The optimal condition was obtained as 30.2 MPa for pressure, 65.6°C for temperature and 258.4 µL for modifier volume. The main components that were extracted with SFE were dillapiole (35.1%), limonene (33.5%) and α-calacorene (25.5%).

  14. Antibacterial activity of essential oil components and their potential use in seed disinfection.

    Science.gov (United States)

    Lo Cantore, Pietro; Shanmugaiah, Vellasamy; Iacobellis, Nicola Sante

    2009-10-28

    Among the main (> or = 0.7%) components of some essential oils, considerable antibacterial activity was shown by terpenoid and phenylpropanoid derivatives containing phenol and alcohol functionalities. A reduced or no activity was shown by those derivatives containing ketones, aldehydes, ethers, and ester functionalities as well as the remaining terpenoids. Eugenol emulsion treatments (1-8 mg/mL) of bean seeds bearing about 2.6 x 10(6) cfu/seed of strain ICMP239 of Xanthomonas campestris pv. phaseoli var. fuscans determined a highly significant reduction of the bacteria on seeds. In particular, eugenol at 4 mg/mL disinfect seeds bearing about 7.0 x 10(2) cfu/seed and lower densities. However, after 72 h, incubation treatments with 2, 4, and 8 mg/mL of eugenol caused germination reduction of 3%, 7%, and 16%, respectively, which was significantly different from the controls. No effect on germination was observed with 1 mg/mL eugenol emulsion treatment. These data indicate eugenol as potentially useful for bean seed disinfection from X. campestris pv. phaseoli var. fuscans. Further studies on the effects on seed vitality and on formulation of essential oils are needed.

  15. The influence of purge times on the yields of essential oil components extracted from plants by pressurized liquid extraction.

    Science.gov (United States)

    Wianowska, Dorota

    2014-01-01

    The influence of different purge times on the yield of the main essential oil constituents of rosemary (Rosmarinus officinalis L.), thyme (Thymus vulgaris L.), and chamomile (Chamomilla recutita L.) was investigated. The pressurized liquid extraction process was performed by applying different extraction temperatures and solvents. The results presented in the paper show that the estimated yield of essential oil components extracted from the plants in the pressurized liquid extraction process is purge time-dependent. The differences in the estimated yields are mainly connected with the evaporation of individual essential oil components and the applied solvent during the purge; the more volatile an essential oil constituent is, the greater is its loss during purge time, and the faster the evaporation of the solvent during the purge process is, the higher the concentration of less volatile essential oil components in the pressurized liquid extraction receptacle. The effect of purge time on the estimated yield of individual essential oil constituents is additionally differentiated by the extraction temperature and the extraction ability of the applied solvent.

  16. Components from the Essential oil of Centaurea aeolica Guss. and C. diluta Aiton from Sicily, Italy

    Directory of Open Access Journals (Sweden)

    Mariem Ben Jemia

    2015-06-01

    Full Text Available Volatile components from florets, leaves and stems and branches of Centaurea aeolica Guss. harvested in Lipari, Sicily, Italy, were analysed by gas phase chomatography (GC and gas chomatography mass spectrometry (GC-MS. The main constituents were β-eudesmol, caryophyllene oxide, ( E -12-norcaryophyll-5-en-2-one and hexahydrofarnesylacetone in flowers, hexahydrofarnesylacetone, 2-methyloctadecane and tricosane in the leaves and hexadecanoic acid , caryophyllene oxide and β-eudesmol in the stems and branches . The analysis of the essential oil of the aerial parts of Centaurea diluta Aiton gave mainly fatty acids and derivatives, the main ones being hexadecanoic acid and (Z,Z-9,12-octadecadienoic acid methyl ester.

  17. Effect of the Rapeseed Oil Methyl Ester Component on Conventional Diesel Fuel Properties

    Directory of Open Access Journals (Sweden)

    Kumbár V.

    2015-01-01

    Full Text Available The effect of the rapeseed oil methyl ester (RME component in diesel fuel was assessed. Dynamic viscosity and density of blends were particularly observed. Measurements were performed at standard constant temperature. Increasing ratio of RME in diesel fuel was reflected in increased density value and dynamic viscosity of the blend. In the case of pure RME, pure diesel fuel, and the blend of both, temperature dependence of dynamic viscosity and density was examined. Considerable temperature dependence of dynamic viscosity and density was found out and demonstrated for all three samples. This finding is in accordance with theoretical assumptions and literature data sources. Mathematical models were developed and tested. Temperature dependence of dynamic viscosity was modelled using the 3rd degree polynomial. Temperature dependence of density was modelled using the 2nd degree polynomial. The proposed models can be used for flow behaviour prediction of RME, diesel fuel, and their blends.

  18. Seasonal variations of Laurus nobilis L. leaves volatile oil components in Isfahan, Iran

    Directory of Open Access Journals (Sweden)

    Y. Shokoohinia

    2014-08-01

    Full Text Available Laurus nobilis L. (sweet laurel is one of the volatile oil bearing plants of Lauraceae family. It is cultivated in different parts of Iran and its leaves and fruits have been used in food, cosmetics and pharmaceutical industries. There are a few reports about the effects of some environmental conditions on the quality and quantity of laurel volatiles. The goal of our work was to search the seasonal variations on the L. nobilis leaves volatile composition. The volatiles of four samples of the dried leaves of L. nobilis collected in March, June, September and December 2009 in Isfahan, Iran were prepared by using a Clevenger type apparatus for 3 hours and were analyzed by gas chromatography-mass spectroscopy. Twenty-nine, thirty-one, thirty-three and thirty-four components consisting 96.91%, 97.66%, 97.46% and 95.44% of the total compounds were identified of the volatiles obtained with yields of 1.1%, 1.5%, 1.4% and 0.8% (w/w, subsequently. The main compound was found to be 1,8-cineole (30.80-40.25%. Although twenty-seven out of thirty-six volatile components were similar in different seasons, there were some differences between other compounds of our four samples. While the essential oil composition of the March and June plant samples were characterized by presence of 1,8-cineole, δ-3-carene and camphor, the volatiles of September and December plant samples contained 1,8-cineole, camphene and sabinene. Some compounds like eugenol, methyl eugenol and α-terpenyl acetate were not affected apparently by seasonal changes.

  19. Brewster angle microscopy of Langmuir films of athabasca bitumens, n-C5 asphaltenes, and SAGD bitumen during pressure-area hysteresis.

    Science.gov (United States)

    Hua, Yujuan; Angle, Chandra W

    2013-01-08

    Bitumen films formed on water surfaces have negative consequences, both environmental and economic. CanmetENERGY has placed considerable research emphasis on understanding the structures of the bitumen films on water as a necessary step before optimization of bitumen extraction. The detailed structures of the adsorbed molecules and, especially, the role of asphaltene molecules at the interfaces are still under scrutiny and debate. In the present study, we compared bitumen and asphaltene films as they were compressed and expanded under various surface pressures in order to achieve a clearer understanding of bitumen film structures. We used a customized NIMA Langmuir trough interfaced to a Brewster angle microscope (BAM) and CCD camera (Nanofilm_ep3BAM, Accurion, previously Nanofilm Gmbh) to study images of bitumen films at the air/water interface. The bitumen film appeared uniform with high reflectivity at a surface pressure of 18 mN·m(-1) and exhibited a coarse pebblelike interface with reduced reflectivity in the liquid condensed (LC) phase at higher pressures (18-35 mN·m(-1)). During the first cycle of compression asphaltene films showed well-defined phase transitions and a uniformly smooth interface in the LC phase between 9 and 35 mN·m(-1). However, folding or buckling occurred at surface pressures from 35 to 44 mN·m(-1). On expansion, asphaltene films appeared to break into islands. The hysteresis of the pressure-area isotherm was much larger for asphaltenes than for bitumen. In both compression and expansion cycles, BAM images for bitumen films appeared to be more reproducible than those of the asphaltene films at the same surface pressures. Films for low-°API SAGD bitumen were almost identical to those for surface-mined bitumen. Films formed from partially deasphalted surface-mined bitumens showed higher compressibility and lower rigidity than the original bitumen. The BAM images illustrated significant differences between the partially deasphalted and

  20. Sesame Oil and Rice Bran Oil Ameliorates Adjuvant-Induced Arthritis in Rats: Distinguishing the Role of Minor Components and Fatty Acids.

    Science.gov (United States)

    Yadav, Nayana Venugopal; Sadashivaiah; Ramaiyan, Breetha; Acharya, Pooja; Belur, Lokesh; Talahalli, Ramaprasad Ravichandra

    2016-12-01

    Though present in small amounts, the minor constituents of dietary oils may supplement the dietary therapies for rheumatoid arthritis (RA). Hence, in the present study, we assessed the effect of minor constituents from sesame oil (SO) and rice bran oil (RBO) and their fatty acids on the severity of adjuvant-induced arthritis in experimental rats. Rats were gavaged with 1 mL of SO or RBO or groundnut oil (GNO, control) with or without its minor components for a period 15 days before and 15 days after the induction of arthritis. Oxidative stress, markers of RA, eicosanoids, cytokines, paw swelling and joint integrity were measured in experimental and control rats. Results demonstrated that native SO and RBO but not SO and RBO stripped of their minor components decreased severity of paw inflammation, oxidative stress (lipid peroxides, protein carbonyls, nitric oxide), RA markers (RF and CRP), inflammatory eicosanoids (PGE2, LTB4 and LTC4) and cytokines (IL-1β, IL-6, MCP-1 and TNF-α) compared to control rats. Native SO and RBO inhibited hydrolytic enzymes (collagenase, elastase and hyaluronidase) in the synovial tissue compared to SO and RBO without minor components. The arthritic scores assessed based on the digital and X-ray images indicated that native oils but not those without their minor components reduced the paw swelling and bone loss. Our results indicated that minor components of SO and RBO possess a significant degree of an anti-arthritic effect and are responsible for down regulating inflammation in the experimentally induced arthritis in rats.

  1. 影响煤焦油沥青质测定量的工艺参数%Effect of process parameters on determination of asphaltene from coal tar

    Institute of Scientific and Technical Information of China (English)

    田盼盼; 郗小明; 李冬; 孙智慧; 李稳宏

    2014-01-01

    Solvent analysis is a method for quantitative separation of coal tar into toluene insoluble, asphaltene (toluene soluble,pentane insoluble),and oil (pentane soluble). The prime objective was to identify the variables in the procedure,including aromatic solvent type,extraction method,amount of toluene solution concentrate (degree of toluene boil-off) ,alkane solvent type,and ratio of n-heptane to toluene solution concentrate that affected the precipitate obtained for asphaltene content. Substitution of toluene with benzene and extraction method did not have a large effect on the precipitate reported for asphaltene. Heptane was chosen as alkane solvent instead of pentane. However amount of toluene solution concentrate and ratio of n-heptane to toluene solution concentrate did have a large effect on the precipitate reported as asphaltene. Coal tar from northern Shaanxi province was tested. With the suitable time of ultrasonic extraction for 3 hours,toluene solution concentrate of 9mL,a 20-fold of n-heptane over toluene solution concentrate,the asphaltene precipitate determined was 13.4%. The separation conditions of asphaltene determination should be indicated when studying the properties and structure of asphaltene from coal tar,since the coal tar separation technique have a large effect on asphaltene precipitated.%煤焦油通过溶剂分析可定量分离为三部分:甲苯不溶物、沥青质和油相。本文主要研究了煤焦油在此分离过程中芳烃溶剂类型、萃取方法、甲苯溶液浓缩量、烷烃溶剂类型和正庚烷溶剂与甲苯溶液浓缩量的添加比例对煤焦油沥青质沉淀量的影响。结果表明,甲苯溶液浓缩量、正庚烷与甲苯溶液浓缩量的添加比例对沥青质沉淀量的影响较大,萃取方法次之,将苯替换成甲苯影响最小。当选择甲苯溶解煤焦油,超声萃取3h,甲苯溶液浓缩量9mL,正庚烷与甲苯溶液浓缩液的添加比例为20∶1时,煤焦

  2. Comparative evaluation of online oil and gas monitor; Avaliacao de monitores de teor de oleo e graxa em linha

    Energy Technology Data Exchange (ETDEWEB)

    Louvisse, Ana Maria Travalloni; Pereira Junior, Oswaldo de Aquino; Jesus, Rafael Ferreira de; Santos, Lino Antonio Duarte dos; Lopes, Humberto Eustaquio [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    Petroleum is predominantly recovered in form of water in oil emulsions, which are stabilised by petroleum resins and asphaltenes, the colloidal disperse components of crude oil. The water phase, separated during the production process, consists of a dilute oil in water emulsion, commonly called produced water.There are a wide variety of methods for determination of oil in produced water that are commercially based on a number of technique. On line continuously monitoring shall be particularly useful in providing information to assist in optimising the separation process and also to attend the environmental legislation for discharge the produced water. There are a wide variety of on line oil in water monitors that are commercially available based on a number of technique. In this paper, a comparative evaluation was made between some methods of on line oil in water detecting. These are light scattering and ultraviolet fluorescence technique. A brief description of the optical methods will be discussed and some of associated problems and limitation are pointed. The work was done in a specific experimental set up that allows the simultaneous pumping of crude oil and water through a calibrated restriction in a pipe has been used. A permanent pressure drop induced by the restriction leads to the dispersion of the oil droplets in the water phase. The monitors based on light scattering technique tested show good agreement between monitor reading and the oil dispersion used. Otherwise for ultraviolet fluorescence based monitors show a significant effect of the variation of oil type. (author)

  3. Essential oil from Chenopodium ambrosioides and main components: activity against Leishmania, their mitochondria and other microorganisms.

    Science.gov (United States)

    Monzote, Lianet; García, Marley; Pastor, Jacinta; Gil, Lizette; Scull, Ramón; Maes, Louis; Cos, Paul; Gille, Lars

    2014-01-01

    Chenopodium ambrosioides is an aromatic herb used by native people to treat parasitic diseases. The aim of this work is to compare the in vitro anti-leishmanial activity of the essential oil (EO) from C. ambrosioides and its major components (ascaridole, carvacrol and caryophyllene oxide) and study their mechanism of action and activity against a panel of microorganism. Antileishmanial activity and cytotoxicity of the EO and major components was study. In addition, experiments to elucidate the mechanism of action were perform and activities against other microorganisms (bacteria, fungi and protozoa) were evaluate. All products were active against promastigote and amastigote forms of Leishmania. Ascaridole exhibited the better antileishmanial activity and the EO the highest selectivity index. The exploration of the mechanism suggests that the products cause a breakdown of mitochondrial membrane potential and a modification of redox indexes. Only EO showed antiprotozoal effect against Plasmodium falciparum and Trypanosoma brucei; while no activity against bacteria and fungi was observed. Our results demonstrate the potentialities of EO in cellular and molecular system, which could be consider in future studies to develop new antileishmanial drugs with a wide anti-parasitic spectrum. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Trypanocidal, trichomonacidal and cytotoxic components of cultivated Artemisia absinthium Linnaeus (Asteraceae essential oil

    Directory of Open Access Journals (Sweden)

    Rafael Alberto Martínez-Díaz

    2015-01-01

    Full Text Available Artemisia absinthium is an aromatic and medicinal plant of ethnopharmacological interest and it has been widely studied. The use of A. absinthium based on the collection of wild populations can result in variable compositions of the extracts and essential oils (EOs. The aim of this paper is the identification of the active components of the vapour pressure (VP EO from a selected and cultivated A. absinthium Spanish population (T2-11 against two parasitic protozoa with different metabolic pathways: Trypanosoma cruzi and Trichomonas vaginalis. VP showed activity on both parasites at the highest concentrations. The chromatographic fractionation of the VP T2-11 resulted in nine fractions (VLC1-9. The chemical composition of the fractions and the antiparasitic effects of fractions and their main compounds suggest that the activity of the VP is related with the presence of trans-caryophyllene and dihydrochamazulene (main components of fractions VLC1 and VLC2 respectively. Additionally, the cytotoxicity of VP and fractions has been tested on several tumour and no tumour human cell lines. Fractions VLC1 and VLC2 were not cytotoxic against the nontumoural cell line HS5, suggesting selective antiparasitic activity for these two fractions. The VP and fractions inhibited the growth of human tumour cell lines in a dose-dependent manner.

  5. Trypanocidal, trichomonacidal and cytotoxic components of cultivatedArtemisia absinthium Linnaeus (Asteraceae essential oil

    Directory of Open Access Journals (Sweden)

    Rafael Alberto Martínez-Díaz

    2015-08-01

    Full Text Available Artemisia absinthium is an aromatic and medicinal plant of ethnopharmacological interest and it has been widely studied. The use ofA. absinthiumbased on the collection of wild populations can result in variable compositions of the extracts and essential oils (EOs. The aim of this paper is the identification of the active components of the vapour pressure (VP EO from a selected and cultivated A. absinthiumSpanish population (T2-11 against two parasitic protozoa with different metabolic pathways: Trypanosoma cruzi andTrichomonas vaginalis. VP showed activity on both parasites at the highest concentrations. The chromatographic fractionation of the VP T2-11 resulted in nine fractions (VLC1-9. The chemical composition of the fractions and the antiparasitic effects of fractions and their main compounds suggest that the activity of the VP is related with the presence oftrans-caryophyllene and dihydrochamazulene (main components of fractions VLC1 and VLC2 respectively. Additionally, the cytotoxicity of VP and fractions has been tested on several tumour and no tumour human cell lines. Fractions VLC1 and VLC2 were not cytotoxic against the nontumoural cell line HS5, suggesting selective antiparasitic activity for these two fractions. The VP and fractions inhibited the growth of human tumour cell lines in a dose-dependent manner.

  6. Antifungal Activity of the Essential Oil of Illicium verum Fruit and Its Main Component trans-Anethole

    Directory of Open Access Journals (Sweden)

    Qi Wang

    2010-10-01

    Full Text Available In order to identify natural products for plant disease control, the essential oil of star anise (Illicium verum Hook. f. fruit was investigated for its antifungal activity on plant pathogenic fungi. The fruit essential oil obtained by hydro-distillation was analyzed for its chemical composition by gas chromatography (GC and gas chromatography-mass spectrometry (GC-MS. trans-Anethole (89.5%, 2-(1-cyclopentenyl-furan (0.9% and cis-anethole (0.7% were found to be the main components among 22 identified compounds, which accounted for 94.6% of the total oil. The antifungal activity of the oil and its main component trans-anethole against plant pathogenic fungi were determined. Both the essential oil and trans-anethole exhibited strong inhibitory effect against all test fungi indicating that most of the observed antifungal properties was due to the presence of trans-anethole in the oil, which could be developed as natural fungicides for plant disease control in fruit and vegetable preservation.

  7. Solids precipitation in crude oils, gas-to-liquids and their blends

    Science.gov (United States)

    Ramanathan, Karthik

    Gas-to-liquids (GTL) liquids are obtained from syngas by the Fischer-Tropsch synthesis. The blending of GTL liquids produced from natural gas/coal reserves and crude oils is a possibility in the near future for multiple reasons. Solids precipitation is a major problem in pipelines and refineries leading to significant additional operating costs. The effect of the addition of a paraffinic GTL liquid to crude oils on solids precipitation was investigated in this study. A Fourier transform infrared (FT-IR) spectroscopic technique was used to obtain solid-liquid equilibria (SLE) data for the various samples. The SLE of multiple systems of model oils composed of n-alkanes was investigated preliminarily. Blends of a model oil simulating a GTL liquid composition and a crude oil showed that the wax precipitation temperature (WPT) decreased upon blending. Three crude oils from different geographic regions (Alaskan North Slope, Colorado and Venezuela) and a laboratory-produced GTL liquid were used in the preparation of blends with five different concentrations of the GTL liquid. The wax precipitation temperatures of the blends were found to decrease with the increasing addition of the GTL liquid for all the oils. This effect was attributed to the solvent effect of the low molecular weight-paraffinic GTL liquid on the crude oils. The weight percent solid precipitated that was estimated as a function of temperature did not show a uniform trend for the set of crude oils. The asphaltene onset studies done on the blends with near-infrared spectroscopy indicated that the addition of GTL liquid could have a stabilizing effect on the asphaltenes in some oils. Analytical techniques such as distillation, solvent separation, HPLC, GC, and GPC were used to obtain detailed composition data on the samples. Two sets of compositional data with 49 and 86 pseudo-components were used to describe the three crude oils used in the blending work. The wax precipitation was calculated using a

  8. HPLC evaluation of the minor lipid components of by-products resulting from edible oil processing

    Directory of Open Access Journals (Sweden)

    EL-Shami, Safinaz Mohamed M.

    2006-12-01

    Full Text Available An analytical evaluation of some by-products resulting from edible oil refining processing steps has been carried out. By-product samples were taken from four different local refineries that apply chemical refining technology. Pretreatment of the representative samples of the by-products were done prior to analysis followed by chromatographic isolation and derivatization of the minor components, namely, free and acylated sterol (FS and AS as well as free and acylated sterylglycosides (FSG and ASG. However, tocopherols were directly determined in the pretreated samples. HPLC, using different detectors, was carried out for the determination of these minor components. Several authors have focused on the analysis of sterols and sterol esters, as well as tocopherols in the refining byproducts; however sterylglycosides, as biologically important components, have not been dealt with. This study throws light on the by – products enriched with certain minor components to be possibly utilized as sources for such components. Also, the role of the conditions of the refining steps followed in removing these valuable minor components from oils was discussed. It was found that soapstock samples contained various amounts of total tocopherols ranging from 80 to 230ppm; total FS and AS ranged from 240 to 4000 mg/100g while total FSG and ASG ranged from 1120 to 6375 mg/100g. In the case of deodorization distillate samples total tocopherols ranged from 960 to 7360ppm; total FS and AS ranged from 1020 to 4160 mg/100g and total FSG, ASG ranged from 395 to 880 mg/100g.El trabajo realiza una evaluación analítica de algunos subproductos resultantes del la refinación de aceites comestibles. Las muestras procedieron de 4 plantas que aplicaban refinación química. Después de un pretratamiento de las muestras estas se sometieron a un análisis cromatográfico para el aislamiento y derivatización de los siguientes componentes minoritarios: esteroles libres y

  9. Characterization of Physically and Chemically Separated Athabasca Asphaltenes Using Small-Angle X-ray Scattering

    Energy Technology Data Exchange (ETDEWEB)

    Amundaraín Hurtado, Jesús Leonardo; Chodakowski, Martin; Long, Bingwen; Shaw, John M. (Alberta)

    2012-02-07

    Athabasca asphaltenes were characterized using small-angle X-ray scattering (SAXS). Two methods were used to separate asphaltenes from the Athabasca bitumen: namely, chemical separation by precipitation with n-pentane and physical separation by nanofiltration using a zirconia membrane with a 20 nm average pore size. The permeate and chemically separated samples were diluted in 1-methylnaphtalene and n-dodecane prior to SAXS measurements. The temperature and asphaltene concentration ranges were 50-310 C and 1-10.4 wt %, respectively. Model-independent analysis of SAXS data provided the radius of gyration and the scattering coefficients. Model-dependent fits provided size distributions for asphaltenes assuming that they are dense and spherical. Model-independent analysis for physically and chemically separated asphaltenes showed significant differences in nominal size and structure, and the temperature dependence of structural properties. The results challenge the merits of using chemically separated asphaltene properties as a basis for asphaltene property prediction in hydrocarbon resources. While the residuals for model-dependent fits are small, the results are inconsistent with the structural parameters obtained from model-independent analysis.

  10. Antioxidant activities of Vine Tea (Ampelopsis grossedentata) extract and its major component dihydromyricetin in soybean oil and cooked ground beef.

    Science.gov (United States)

    Ye, Liyun; Wang, Hengjian; Duncan, Susan E; Eigel, William N; O'Keefe, Sean F

    2015-04-01

    Antioxidant activities of Ampelopsis grossedentata extract (EXT) and its major component dihydromyricetin (DHM) were analysed and compared with BHA in two model systems, soybean oil and cooked ground beef. Oxidation of soybean oil samples was measured using peroxide value, anisidine value, headspace volatiles and headspace oxygen content. TBARS (thiobarbituric acid reactive substances) test was used to measure the oxidation of cooked beef. DHM was more potent than BHA in preventing soybean oil oxidation. EXT was not as effective as BHA or DHM in soybean oil. In cooked beef, all three antioxidants significantly lowered oxidation compared to control, but there were no differences between the three. Mechanisms and potentials of EXT and DHM as natural food antioxidants need to be studied on a case-by-case basis.

  11. Characterization of oil and gas reservoir heterogeneity

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The objective of the cooperative research program is to characterize Alaskan reservoirs in terms of their reserves, physical and chemical properties, geologic configuration and structure, and the development potential. The tasks completed during this period include: (1) geologic reservoir description of Endicott Field; (2) petrographic characterization of core samples taken from selected stratigraphic horizons of the West Sak and Ugnu (Brookian) wells; (3) development of a polydispersed thermodynamic model for predicting asphaltene equilibria and asphaltene precipitation from crude oil-solvent mixtures, and (4) preliminary geologic description of the Milne Point Unit.

  12. [Determination of chemical components of volatile oil from Cuminum cyminum L. by gas chromatography-mass spectrometry].

    Science.gov (United States)

    Yan, Jian-hui; Tang, Ke-wen; Zhong, Ming; Deng, Ning-hua

    2002-11-01

    Volatile oil was extracted from Cuminum cyminum L. by using steam distillation. More than sixty peaks were separated and 49 compounds were identified by gas chromatography-mass spectrometry (GC-MS). The relative amounts of the components were determined by area normalization method. Among the 49 compounds identified, there were 16 hydrocarbons and 32 oxygenated compounds. The main compnents were cuminal and safranal (accounting for 32.26% and 24.46% respectively in the components identified). The other nine compounds with contents all over 1%, were monterpenes, sesquiterpenes, aromatic aldehydes and aromatic oxides etc. The other components with relatively small amounts were chiefly terpenes, terpenols, terpenals, terpenones, terpene esters and aromatic compounds. It is good to separate polar and apolar components in the volatile oil from Cuminum cyminum L. on the GC capillary column of moderate polarity.

  13. Antimicrobial activity of essential oils and their components against the three major pathogens of the cultivated button mushroom

    NARCIS (Netherlands)

    Sokovic, M.; Griensven, van L.J.L.D.

    2006-01-01

    Essential oils of Matricaria chamommilla, Mentha piperita, M. spicata, Lavandula angusti folia, Ocimum basilicum, Thymus vulgaris, Origanum vulgare, Salvia officinalis, Citrus limon and C. aurantium and their components; linalyl acetate, linalool, limonene, ¿-pinene, ß-pinene, 1,8-cineole, camphor,

  14. Antimicrobial activity of essential oils and their components against the three major pathogens of the cultivated button mushroom

    NARCIS (Netherlands)

    Sokovic, M.; Griensven, van L.J.L.D.

    2006-01-01

    Essential oils of Matricaria chamommilla, Mentha piperita, M. spicata, Lavandula angusti folia, Ocimum basilicum, Thymus vulgaris, Origanum vulgare, Salvia officinalis, Citrus limon and C. aurantium and their components; linalyl acetate, linalool, limonene, ¿-pinene, ß-pinene, 1,8-cineole, camphor,

  15. GLC analysis of poison ivy and poison oak urushiol components in vegetable oil preparations.

    Science.gov (United States)

    Elsohly, M A; Turner, C E

    1980-05-01

    A procedure is described for the analysis of urushiol content of pharmaceutical preparations containing extracts of poison ivy (Toxicodendron radicans) and poison oak (T. diversilobum) in vegetable oils. The procedure involves extraction of the urushiols from the oily solutions using 90% methanol in water followed by GLC analysis of the extracts. Recoveries of both poison ivy and poison oak urushiols from solutions in corn oil, olive oil, sesame seed oil, and cottonseed oil were calculated. Correlation coefficients (r2) ranged from 0.97 to 1.00, and the coefficients of variations ranged from 3.08 to 7.90%.

  16. Evapotranspiration components determined by eddy covariance and sap flux measurements in oil palm plantations in Sumatra, Indonesia

    Science.gov (United States)

    Meijide, Ana; Röll, Alexander; Niu, Furong; June, Tania; Hölscher, Dirk; Knohl, Alexander

    2015-04-01

    The expansion of oil palm cultivation fueled by the increasing global demand for palm oil is leading to massive land transformations in tropical areas, particularly in South-East Asia. Conversions of forest land to oil palm plantations likely affect ecosystem water fluxes. However, there is a lack of information on water fluxes from oil palm plantations as well as on the partitioning of these fluxes into its different components such as transpiration and evaporation. It is expected that water fluxes from oil palm plantations vary temporally, both long-term, i.e. between different age-classes of plantations, and short-term, i.e. from day to day within a certain plantation (e.g. during or after periods of rainfall). A proper evaluation of water fluxes from oil palm plantations thus requires an experimental design encompassing these types of variability. To assess evapotranspiration (ET) rates, an eddy covariance tower was installed in a 2-year-old oil palm plantation in the lowlands of Jambi, Sumatra; it was subsequently moved to a 12-year-old oil palm plantation located in the same region. In parallel to the ET, sap flux density was measured on 16 leaf petioles on four oil palms; stand transpiration rates were derived from these measurements with stand inventory data. The parallel measurements ran for several weeks in both plantations. Preliminary results for our period of study show that the average ET rate of the 2-year-old oil palm plantation was 5.2 mm day-1; values up to 7.0 mm day-1 were observed on dry, sunny days with non-limiting soil moisture. Stand transpiration (T) by the young oil palms was very low, 0.3 mm day-1on average, and only showed a small variation between days. Under optimal environmental conditions, the ratio of T to total ET was up to 0.08 in the young plantation, while in the mature, 12-year-old plantation, it was significantly higher and reached 0.5. Transpiration rates in the mature oil palm plantation were about six- to seven-fold higher

  17. Control of Aspergillus flavus in maize with plant essential oils and their components.

    Science.gov (United States)

    Montes-Belmont, R; Carvajal, M

    1998-05-01

    The effects of 11 plant essential oils for maize kernel protection against Aspergillus flavus were studied. Tests were conducted to determine optimal levels of dosages for maize protection, effects of combinations of essential oils, and residual effects and toxicity of essential oils to maize plants. Principal constituents of eight essential oils were tested for ability to protect maize kernels. Essential oils of Cinnamomum zeylanicum (cinnamon), Mentha piperita (peppermint), Ocimum basilicum (basil), Origanum vulgare (origanum), Teloxys ambrosioides (the flavoring herb epazote), Syzygium aromaticum (clove), and Thymus vulgaris (thyme) caused a total inhibition of fungal development on maize kernels. Thymol and o-methoxycinnamaldehyde significantly reduced maize grain contamination. The optimal dosage for protection of maize varied from 3 to 8%. Combinations of C. zeylanicum with the remaining oils gave efficient control. A residual effect of C. zeylanicum was detected after 4 weeks of kernel treatment. No phytotoxic effect on germination and corn growth was detected with any of these oils.

  18. Pyrolysis mechanisms of thiophene and methylthiophene in asphaltenes.

    Science.gov (United States)

    Song, Xinli; Parish, Carol A

    2011-04-07

    The pyrolysis mechanisms of thiophene in asphaltenes have been investigated theoretically using density functional and ab initio quantum chemical techniques. All of the possible reaction pathways were explored using B3LYP, MP2, and CBS-QB3 models. A comparison of the calculated heats of reaction with the available experimental values indicates that the CBS-QB3 level of theory is quantitatively reliable for calculating the energetic reaction paths of the title reactions. The pyrolysis process is initiated via four different types of hydrogen migrations. According to the reaction barrier heights, the dominant 1,2-H shift mechanism involves two competitive product channels, namely, C(2)H(2) + CH(2)CS and CS + CH(3)CCH. The minor channels include the formation of CS + CH(2)CCH(2), H(2)S + C(4)H(2), HCS + CH(2)CCH, CS + CH(2)CHCH, H + C(4)H(3)S, and HS + C(4)H(3). The methyl substitution effect was investigated with the pyrolysis of 2-methylthiophene and 3-methylthiophene. The energetics of such systems were very similar to that for unsubstituted thiophene, suggesting that thiophene alkylation may not play a significant role in the pyrolysis of asphaltene compounds.

  19. Influence of crude oil composition on wax deposition on tubing wall%原油组成对原油管道结蜡规律的影响

    Institute of Scientific and Technical Information of China (English)

    李传宪; 白帆; 王燕

    2014-01-01

    The wax deposition was studied for man-made crude oil with various compositions (different contents of resin, asphaltene and wax) under various conditions in a rotary wax deposition facility. The influence of the compositions was explored by sediment sampling from tubing wall, analyzing with the differential scanning calorimetry (DSC) and using four components method. Combined with mechanism of the wax deposition initiated by resin and asphaltene, it was found that lower content resin and asphaltene in crude oil could have a synergistic effect with paraffin molecules on the wax deposition, while for higher content resin and asphaltene they were attached to the pipe wall in the form of paste, although the existence of resin and asphaltene could weaken the driving force for paraffin molecule migration and impede deposition of paraffin molecules. The results obtained from studying on the effect of various wax contents on wax deposition showed that higher average carbon number of paraffin molecules in man-made crude oil was, less content of wax in the wax layer deposited. But the paraffin molecules with more carbon number could take place eutectic roles with resin and asphaltene easily, due to they were of longer carbon chain, leading to they was easier to deposit on the pipe wall with resin and asphaltene together.%利用旋转式动态结蜡装置,对不同组成的人工油样(胶质和沥青质含量不同或蜡含量不同)进行了不同条件下的实验研究。通过对管壁沉积物取样并利用差式扫描量热法(DSC)和四组分法进行分析,探究了不同原油组成对结蜡的影响规律。结合胶质和沥青质在结蜡过程中的作用机理,发现胶质和沥青质的存在虽然总会削弱蜡分子的迁移动力,阻碍蜡分子的沉积,但在含量较小时会协同蜡分子的沉积作用,而当含量较大时会以粘壁的形式附着于管壁。对蜡含量不同原油的结蜡规律研究发现:原油所含

  20. A Simple and Effective Mass Spectrometric Approach to Identify the Adulteration of the Mediterranean Diet Component Extra-Virgin Olive Oil with Corn Oil

    Directory of Open Access Journals (Sweden)

    Francesco Di Girolamo

    2015-09-01

    Full Text Available Extra virgin olive oil (EVOO with its nutraceutical characteristics substantially contributes as a major nutrient to the health benefit of the Mediterranean diet. Unfortunately, the adulteration of EVOO with less expensive oils (e.g., peanut and corn oils, has become one of the biggest source of agricultural fraud in the European Union, with important health implications for consumers, mainly due to the introduction of seed oil-derived allergens causing, especially in children, severe food allergy phenomena. In this regard, revealing adulterations of EVOO is of fundamental importance for health care and prevention reasons, especially in children. To this aim, effective analytical methods to assess EVOO purity are necessary. Here, we propose a simple, rapid, robust and very sensitive method for non-specialized mass spectrometric laboratory, based on the matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS coupled to unsupervised hierarchical clustering (UHC, principal component (PCA and Pearson’s correlation analyses, to reveal corn oil (CO adulterations in EVOO at very low levels (down to 0.5%.

  1. A Simple and Effective Mass Spectrometric Approach to Identify the Adulteration of the Mediterranean Diet Component Extra-Virgin Olive Oil with Corn Oil.

    Science.gov (United States)

    Di Girolamo, Francesco; Masotti, Andrea; Lante, Isabella; Scapaticci, Margherita; Calvano, Cosima Damiana; Zambonin, Carlo; Muraca, Maurizio; Putignani, Lorenza

    2015-09-01

    Extra virgin olive oil (EVOO) with its nutraceutical characteristics substantially contributes as a major nutrient to the health benefit of the Mediterranean diet. Unfortunately, the adulteration of EVOO with less expensive oils (e.g., peanut and corn oils), has become one of the biggest source of agricultural fraud in the European Union, with important health implications for consumers, mainly due to the introduction of seed oil-derived allergens causing, especially in children, severe food allergy phenomena. In this regard, revealing adulterations of EVOO is of fundamental importance for health care and prevention reasons, especially in children. To this aim, effective analytical methods to assess EVOO purity are necessary. Here, we propose a simple, rapid, robust and very sensitive method for non-specialized mass spectrometric laboratory, based on the matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) coupled to unsupervised hierarchical clustering (UHC), principal component (PCA) and Pearson's correlation analyses, to reveal corn oil (CO) adulterations in EVOO at very low levels (down to 0.5%).

  2. Acaricidal activity of Thymus vulgaris oil and its main components against Tyrophagus putrescentiae, a stored food mite.

    Science.gov (United States)

    Jeong, E Y; Lim, J H; Kim, H G; Lee, H S

    2008-02-01

    The acaricidal activities of compounds derived from Thymus vulgaris (thyme) oil against Tyrophagus putrescentiae were assessed using an impregnated fabric disk bioassay, and were compared with those of the synthetic acaricides, benzyl benzoate and N,N-diethyl-m-toluamide. The observed responses differed according to dosage and chemical components. The 50% lethal dose (LD50) value of the T. vulgaris oil against T. putrescentiae was 10.2 microg/cm2. Biologically active constituents derived from T. vulgaris oil were purified by using silica gel chromatography and high-performance liquid chromatography. The structures of acaricidal components were analyzed by gas chromatography-mass spectrometry, 1H nuclear magnetic resonance (NMR), 13C NMR, 1H-13C COSY-NMR, and DEPT-NMR spectra, and were subsequently identified as carvacrol and thymol. Carvacrol was the most toxic compound with LD50 values (4.5 microg/cm2) significantly different from thymol (11.1 microg/cm2), benzyl benzoate (11.3 microg/cm2), and N,N-diethyl-m-toluamide (13.9 microg/cm2). Linalool was as toxic as was N,N-diethyl-m-toluamide. The lower LD50 of carvacrol indicates that it may be the major contributor of the toxicity of T. vulagaris oil against the stored food mite, although it only constitutes 14.2% of the oil. From this point of view, carvacrol and thymol can be very useful as potential control agents against stored food mite.

  3. Thermodynamic analysis of steam assisted conversions of bio-oil components to synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Aktas, Seda; Karakaya, Mustafa; Avci, Ahmet K. [Department of Chemical Engineering, Bogazici University, Bebek 34342, Istanbul (Turkey)

    2009-02-15

    The aim of this study is to investigate the thermodynamics of steam assisted, high-pressure conversions of model components of bio-oil - isopropyl alcohol, lactic acid and phenol - to synthesis gas (H{sub 2} + CO) and to understand the effects of process variables such as temperature and inlet steam-to-fuel ratio on the product distribution. For this purpose, thermodynamic analyses are performed at a pressure of 30 bar and at ranges of temperature and steam-to-fuel ratio of 600-1200 K and 4-9, respectively. The number of moles of each component in the product stream and the product composition at equilibrium are calculated via Gibbs free energy minimization technique. The resulting optimization problems are solved by using the Sequential quadratic programming method. The results showed that all of the model fuels reached near-complete conversions to H{sub 2}, CO, CO{sub 2} and CH{sub 4} within the range of operating conditions. Temperature and steam-to-fuel ratio had positive effects in increasing hydrogen content of the product mixture at different magnitudes. Production of CO increased with temperature, but decreased at high steam-to-fuel ratios. Conversion of model fuels in excess of 1000 K favored molar H{sub 2}/CO ratios around 2, the synthesis gas composition required for Fischer-Tropsch and methanol syntheses. It was also possible to adjust the H{sub 2}/CO ratios and the amounts of CH{sub 4} and CO{sub 2} in synthesis gas by steam-to-fuel ratio, the value depending on temperature and the fuel type. Product distribution trends indicated the presence of water-gas shift and methanation equilibria as major side reactions running in parallel with the steam reforming of the model hydrocarbons. (author)

  4. Myrtaceae Plant Essential Oils and their β-Triketone Components as Insecticides against Drosophila suzukii

    Directory of Open Access Journals (Sweden)

    Chung Gyoo Park

    2017-06-01

    Full Text Available Spotted wing drosophila (SWD, Drosophila suzukii (Matsumura, Diptera: Drosophilidae is recognized as an economically important pest in North America and Europe as well as in Asia. Assessments were made for fumigant and contact toxicities of six Myrtaceae plant essential oils (EOs and their components to find new alternative types of insecticides active against SWD. Among the EOs tested, Leptospermum citratum EO, consisting mainly of geranial and neral, exhibited effective fumigant activity. Median lethal dose (LD50; mg/L values of L. citratum were 2.39 and 3.24 for males and females, respectively. All tested EOs except Kunzea ambigua EO exhibited effective contact toxicity. LD50 (µg/fly values for contact toxicity of manuka and kanuka were 0.60 and 0.71, respectively, for males and 1.10 and 1.23, respectively, for females. The LD50 values of the other 3 EOs-L. citratum, allspice and clove bud were 2.11–3.31 and 3.53–5.22 for males and females, respectively. The non-polar fraction of manuka and kanuka did not show significant contact toxicity, whereas the polar and triketone fractions, composed of flavesone, isoleptospermone and leptospermone, exhibited efficient activity with the LD50 values of 0.13–0.37 and 0.22–0.57 µg/fly for males and females, respectively. Our results indicate that Myrtaceae plant EOs and their triketone components can be used as alternatives to conventional insecticides.

  5. Relationship between total polar components and polycyclic aromatic hydrocarbons in fried edible oil.

    Science.gov (United States)

    An, Ke-Jing; Liu, Yu-Lan; Liu, Hai-Lan

    2017-09-01

    Deep-fried dough sticks (a Chinese traditional breakfast) were fried individually in peanut, sunflower, rapeseed, rice bran, soybean and palm oil without any time lag for 32 h (64 batches fried, each for 30 min) and fried oil samples were obtained every 2 h. The frying-induced changes in the levels of total polar compounds (TPC) and polycyclic aromatic hydrocarbons (PAHs) were investigated by edible oil polar compounds (EOPC) fast separation chromatographic system and gas chromatography-mass spectrometry (GC-MS), respectively. The correlations were analysed of TPC with benzo[a]pyrene (BaP), TPC and PAH4 (benzo[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene) as well as TPC with PAH16 (USEPA 16 PAHs). The results revealed that the levels of TPC and PAHs in fried oil considerably increased with frying time, and the type of oil affected their formation, which could inform the choice of oil for frying. The total BaP equivalents (∑BaPeq) concentrations in fresh oil and in oil whose TPC exceeded 27% were 2.14-13.48 and 5.78-10.80 μg kg(-1), respectively, which means that the carcinogenic potency of frying oil was more pronounced than that of fresh oil. In addition, the TPC concentration was significantly correlated with the concentrations of the sum of the 16 PAHs, PAH4 and BaP, so that the levels of PAHs could be predicted according to the levels of TPC in fried oil. In European standards, the rejection point for TPC in frying oil should be recalculated when considered PAHs. In all, the concentration of PAHs is a vital factor for ensuring the safety of frying oil.

  6. Anti-oxidant activity and major chemical component analyses of twenty-six commercially available essential oils.

    Science.gov (United States)

    Wang, Hsiao-Fen; Yih, Kuang-Hway; Yang, Chao-Hsun; Huang, Keh-Feng

    2017-10-01

    This study analyzed 26 commercially available essential oils and their major chemical components to determine their antioxidant activity levels by measuring their total phenolic content (TPC), reducing power (RP), β-carotene bleaching (BCB) activity, trolox equivalent antioxidant capacity (TEAC), and 1,1-diphenyl-2-picrylhydrazyl free radical scavenging (DFRS) ability. The clove bud and thyme borneol essential oils had the highest RP, BCB activity levels, and TPC values among the 26 commercial essential oils. Furthermore, of the 26 essential oils, the clove bud and ylang ylang complete essential oils had the highest TEAC values, and the clove bud and jasmine absolute essential oils had the highest DFRS ability. At a concentration of 2.5 mg/mL, the clove bud and thyme borneol essential oils had RP and BCB activity levels of 94.56% ± 0.06% and 24.64% ± 0.03% and 94.58% ± 0.01% and 89.33% ± 0.09%, respectively. At a concentration of 1 mg/mL, the clove bud and thyme borneol essential oils showed TPC values of 220.00 ± 0.01 and 69.05 ± 0.01 mg/g relative to gallic acid equivalents, respectively, and the clove bud and ylang ylang complete essential oils had TEAC values of 809.00 ± 0.01 and 432.33 ± 0.01 μM, respectively. The clove bud and jasmine absolute essential oils showed DFRS abilities of 94.13% ± 0.01% and 78.62% ± 0.01%, respectively. Phenolic compounds of the clove bud, thyme borneol and jasmine absolute essential oils were eugenol (76.08%), thymol (14.36%) and carvacrol (12.33%), and eugenol (0.87%), respectively. The phenolic compounds in essential oils were positively correlated with the RP, BCB activity, TPC, TEAC, and DFRS ability. Copyright © 2017. Published by Elsevier B.V.

  7. Component composition of essential oils and ultrastructure of secretory cells of resin channel needles Juniperus communis (Cupressaceae

    Directory of Open Access Journals (Sweden)

    N. V. Gerling

    2015-12-01

    Full Text Available The results of determining the qualitative and quantitative composition of essential oil Juniperus communis, growing under the canopy of spruce blueberry sphagnum subzone middle taiga. Juniperus communis essential oil is liquid light yellow color. The content of essential oil was 0.46 % in shoots with needles. 37 substances of components identified. Mass fraction of components in the essential oil of Juniperus communis reached 89 %. The highest percentage of occupied fraction of monoterpenes (82.3 %, the proportion of sesquiterpenes less than 0.5 % of the total composition of essential oils, alcohols 3.5 and 0.7 % esters. In monoterpenes fraction predominant α-pinene (24.5–32.6 %, β-pinene (15–20.3 % and α-phellandrene (6.4–8.8 %. Essential oil of Juniperus communis is characterized by high content of monoterpenoids in contrast to other conifers of the taiga zone. All stages of biosynthesis essential oils occur in the epithelial cells of the resin channel (terpenoidogennyh cells. An oval shape have epithelial cells of the resin channel needles in transverse sections the Juniperus communis, which is situated vacuole in the center. Large number of lipid globules (up to 40 noted in the hyaloplasm of explored cells. Leucoplasts surrounded by membranes of smooth endoplasmic reticulum in cross sections of epithelial cells in resin channel of juniper. Endoplasmic reticulum is poorly developed in epithelial cells, which corresponds to the low content of sesquiterpenes in the needles during the study period. Development of large leucoplasts and large number of mitochondria associated with predominance of synthesis monoterpenoids the in the epithelium cells resin channel.

  8. Antimicrobial activities of commercial essential oils and their components against food-borne pathogens and food spoilage bacteria.

    Science.gov (United States)

    Mith, Hasika; Duré, Rémi; Delcenserie, Véronique; Zhiri, Abdesselam; Daube, Georges; Clinquart, Antoine

    2014-07-01

    This study was undertaken to determine the in vitro antimicrobial activities of 15 commercial essential oils and their main components in order to pre-select candidates for potential application in highly perishable food preservation. The antibacterial effects against food-borne pathogenic bacteria (Listeria monocytogenes, Salmonella Typhimurium, and enterohemorrhagic Escherichia coli O157:H7) and food spoilage bacteria (Brochothrix thermosphacta and Pseudomonas fluorescens) were tested using paper disk diffusion method, followed by determination of minimum inhibitory (MIC) and bactericidal (MBC) concentrations. Most of the tested essential oils exhibited antimicrobial activity against all tested bacteria, except galangal oil. The essential oils of cinnamon, oregano, and thyme showed strong antimicrobial activities with MIC ≥ 0.125 μL/mL and MBC ≥ 0.25 μL/mL. Among tested bacteria, P. fluorescens was the most resistant to selected essential oils with MICs and MBCs of 1 μL/mL. The results suggest that the activity of the essential oils of cinnamon, oregano, thyme, and clove can be attributed to the existence mostly of cinnamaldehyde, carvacrol, thymol, and eugenol, which appear to possess similar activities against all the tested bacteria. These materials could be served as an important natural alternative to prevent bacterial growth in food products.

  9. [Optimization for supercritical CO2 extraction with response surface methodology and component analysis of Sapindus mukorossi oil].

    Science.gov (United States)

    Wu, Yan; Xiao, Xin-yu; Ge, Fa-huan

    2012-02-01

    To study the extraction conditions of Sapindus mukorossi oil by Supercritical CO2 Extraction and identify its components. Optimized SFE-CO2 Extraction by response surface methodology and used GC-MS to analysie Sapindus mukorossi oil compounds. Established the model of an equation for the extraction rate of Sapindus mukorossi oil by Supercritical CO2 Extraction, and the optimal parameters for the Supercritical CO2 Extraction determined by the equation were: the extraction pressure was 30 MPa, temperature was 40 degrees C; The separation I pressure was 14 MPa, temperature was 45 degrees C; The separation II pressure was 6 MPa, temperature was 40 degrees C; The extraction time was 60 min and the extraction rate of Sapindus mukorossi oil of 17.58%. 22 main compounds of Sapindus mukorossi oil extracted by supercritical CO2 were identified by GC-MS, unsaturated fatty acids were 86.59%. This process is reliable, safe and with simple operation, and can be used for the extraction of Sapindus mukorossi oil.

  10. Antimicrobial activities of commercial essential oils and their components against food-borne pathogens and food spoilage bacteria

    Science.gov (United States)

    Mith, Hasika; Duré, Rémi; Delcenserie, Véronique; Zhiri, Abdesselam; Daube, Georges; Clinquart, Antoine

    2014-01-01

    This study was undertaken to determine the in vitro antimicrobial activities of 15 commercial essential oils and their main components in order to pre-select candidates for potential application in highly perishable food preservation. The antibacterial effects against food-borne pathogenic bacteria (Listeria monocytogenes, Salmonella Typhimurium, and enterohemorrhagic Escherichia coli O157:H7) and food spoilage bacteria (Brochothrix thermosphacta and Pseudomonas fluorescens) were tested using paper disk diffusion method, followed by determination of minimum inhibitory (MIC) and bactericidal (MBC) concentrations. Most of the tested essential oils exhibited antimicrobial activity against all tested bacteria, except galangal oil. The essential oils of cinnamon, oregano, and thyme showed strong antimicrobial activities with MIC ≥ 0.125 μL/mL and MBC ≥ 0.25 μL/mL. Among tested bacteria, P. fluorescens was the most resistant to selected essential oils with MICs and MBCs of 1 μL/mL. The results suggest that the activity of the essential oils of cinnamon, oregano, thyme, and clove can be attributed to the existence mostly of cinnamaldehyde, carvacrol, thymol, and eugenol, which appear to possess similar activities against all the tested bacteria. These materials could be served as an important natural alternative to prevent bacterial growth in food products. PMID:25473498

  11. Potential of plant essential oils and their components in animal agriculture – in vitro studies on antibacterial mode of action

    Directory of Open Access Journals (Sweden)

    Corliss A. O'bryan

    2015-09-01

    Full Text Available The broad field of agriculture is currently undergoing major changes in practices, with new catch phrases including organic and sustainable. Consumers are more aware than ever before of the food that they eat and they want food free of toxic chemicals, antibiotics and the like. The antimicrobial activity of essential oils and their components has been recognized for several years. Recent research has demonstrated that many of these essential oils have beneficial effects for livestock, including reduction of foodborne pathogens in these animals. Essential oils as natural antimicrobials offer the opportunity to help maintain the safety of our food supply and minimize consumers’ concerns about consumption of synthetic chemicals. Numerous studies have been made into the mode of action of essential oils and the resulting elucidation of bacterial cell targets have contributed to new perspectives on countering antimicrobial resistance and pathogenicity of these bacteria. In this review, after a brief discussion of the uses essential oils in agriculture as antimicrobials, we give an overview of the current knowledge about the antibacterial mode of action of essential oils and their constituents as determined in vitro.

  12. Citronellol and geraniol, components of rose oil, activate peroxisome proliferator-activated receptor α and γ and suppress cyclooxygenase-2 expression.

    Science.gov (United States)

    Katsukawa, Michiko; Nakata, Rieko; Koeji, Satomi; Hori, Kazuyuki; Takahashi, Saori; Inoue, Hiroyasu

    2011-01-01

    We evaluated the effects of rose oil on the peroxisome proliferator-activated receptor (PPAR) and cyclooxygenase-2 (COX-2). Citronellol and geraniol, the major components of rose oil, activated PPARα and γ, and suppressed LPS-induced COX-2 expression in cell culture assays, although the PPARγ-dependent suppression of COX-2 promoter activity was evident only with citronellol, indicating that citronellol and geraniol were the active components of rose oil.

  13. Effects of sowing dates and different fertilizers on yield, yield components, and oil percentage of castor bean (Ricinus communis L.

    Directory of Open Access Journals (Sweden)

    parviz rezvani moghadam

    2009-06-01

    Full Text Available In order to study the effects of sowing dates and different fertilizers on yield, yield components, and oil percentage of castor bean, an experiment was conducted at Experimental station, College of Agriculture, Ferdowsi University of Mashhad, Iran in years 2004-2005. The experimental treatments comprised all combinations of four sowing dates (11 April, 25 April, 8 May and 22 May and three different fertilizers (cow manure (30 tons/ha, compost (30 tons/ha, chemical fertilizers (100 kg/ha N and 250 kg/ha of super phosphate and no fertilizer as control. Different characteristics such as plant height, main inflorescence height, number of inflorescence per plant, number of secondary stems per plant, number of capsules per plant, number of grain per plant, grain weight per plant, 100 seed weight, grain yield, oil percentage and oil yield were recorded. A factorial arrangement based on a randomized complete block design with three replications was used. The results showed by delaying sowing date grain yield, seed oil percentage and oil yield were decreased, but there was no significant differences between 25 April, 8 May and 22 May sowing dates. Harvest index and 100 seed weight did not affect by neither sowing dates nor fertilizer treatments. The highest number of branches per plant, number of fertile inflorescences per plant, number of fertile capsules per plant, number of grain per plant, grain weight per plant and biological yield were obtained at 8 May sowing date on chemical fertilizer. Percentage of seed oil, grain yield and oil yield was higher at the first sowing date (11 April in compost and chemical fertilizer treatments. Keywords: Castor bean, sowing date, fertilizer, grain yield, oil percentage.

  14. Dispersing of Petroleum Asphaltenes by Acidic Ionic Liquid and Determination by UV-Visible Spectroscopy

    Directory of Open Access Journals (Sweden)

    Eshagh Rezaee Nezhad

    2013-01-01

    Full Text Available Nowadays, constructing a mechanism to prevent the aggregation petroleum asphaltenes by the use of new acidic ionic liquids has become of fundamental importance. In this research, 3-(2-carboxybenzoyl-1-methyl-1H-imidazol-3-ium chloride ([CbMIM] [Cl] and other ionic liquids such as [CbMIM]BF4, [HMIM]Cl, [BMIM]Br, and [HMIM]HSO4 were tested. It should be noted that during the experiment the presence of the acidic ionic liquid moiety enhanced interactions between asphaltenes and acidic ionic liquids and it greatly limited asphaltene aggregation. We considered parameters such as temperature, amount of dispersant, effect of water: toluene ratio, the stirring time and effects of other ionic liquids, and determination of concentration of petroleum asphaltenes after dispersing by acidic ionic liquid under various parameters using UV-Visible spectroscopy.

  15. Additive antimicrobial [corrected] effects of the active components of the essential oil of Thymus vulgaris--chemotype carvacrol.

    Science.gov (United States)

    Iten, Felix; Saller, Reinhard; Abel, Gudrun; Reichling, Jürgen

    2009-09-01

    Herbal remedies are multicomponent mixtures by their nature as well as by pharmaceutical definition. Being a multicomponent mixture is not only a crucial property of herbal remedies, it also represents a precondition for interactions such as synergism or antagonism. Until now, only a few phytomedicines are accurately described concerning the interactions of their active components. The aim of this study was to search for interactions within such a naturally given multi-component mixture and to discuss the pharmaceutical and clinical impacts. The thyme oil chosen for the examination belongs to the essential oils with the most pronounced antimicrobial activity. Antibiotic activity of thyme oil and single active components were tested against six different strains of microorganisms. The checkerboard assay was used to search for interactions. The time-kill assay was used to verify the observed effects and to get information about the temporal resolution of the antimicrobial activity. The degree of the detected interactions corresponded with the demarcating FICI measure of 0.5, which separates the additive from the over-additive (synergistic) effects. Therefore, the observed effect was called a "borderline case of synergism" or, respectively, "partial synergism". Partial synergism was observed only in the presence of Klebsiella pneumoniae. Additive antimicrobial activity was observed for the combination of the two monosubstances carvacrol plus linalool and thymol plus linalool as well as with the combination of the two essential oils of the carvacrol and linalool chemotypes. An increase of the carvacrol oil concentration from one to two times the MIC resulted in a considerable acceleration of the kill-rate. Thyme oil is composed of several different components that show antimicrobial activity (at least: carvacrol, thymol and linalool). The antimicrobial activity of thyme oil is partly based on additive effects, which might especially enhance the rapidity of the

  16. First evidence of mineralization of petroleum asphaltenes by a strain of Neosartorya fischeri

    OpenAIRE

    Uribe‐Alvarez, Cristina; Ayala, Marcela; Perezgasga, Lucia; Naranjo, Leopoldo; Urbina, Héctor; Vazquez‐Duhalt, Rafael

    2011-01-01

    Summary A fungal strain isolated from a microbial consortium growing in a natural asphalt lake is able to grow in purified asphaltenes as the only source of carbon and energy. The asphaltenes were rigorously purified in order to avoid contamination from other petroleum fractions. In addition, most of petroporphyrins were removed. The 18S rRNA and β‐tubulin genomic sequences, as well as some morphologic characteristics, indicate that the isolate is Neosartorya fischeri. After 11 weeks of growt...

  17. Devil's-claw (Proboscidea louisianica), essential oil and its components : Potential allelochemical agents on cotton and wheat.

    Science.gov (United States)

    Riffle, M S; Waller, G R; Murray, D S; Sgaramello, R P

    1990-06-01

    The potential allelopathic activity of devil's-claw [Proboscidea louisianica (Mill.) Thellung] essential oil and a few of the compounds it contains on the elongation of cotton (Gossypium hirsutum L.) and wheat (Triticum aestivum L.) radicles was studied using a Petri dish bioassay. Essential oil was collected by steam distillation using an all-glass-Teflon assembly. Ether extracts of the steam distillates from fresh devil's-claw were inhibitory to cotton and wheat radicle elongation. The following six components of devil's-claw essential oil identified by CGC-MS-DS were inhibitory to cotton and/or wheat at a concentration of 1 mM: vanillin, piperitenone, δ-cadinene,p-cymen-9-ol, α-bisabolol, and phenethyl alcohol.

  18. Computer Modeling of the Displacement Behavior of Carbon Dioxide in Undersaturated Oil Reservoirs

    Directory of Open Access Journals (Sweden)

    Ju Binshan

    2015-11-01

    Full Text Available The injection of CO2 into oil reservoirs is performed not only to improve oil recovery but also to store CO2 captured from fuel combustion. The objective of this work is to develop a numerical simulator to predict quantitatively supercritical CO2 flooding behaviors for Enhanced Oil Recovery (EOR. A non-isothermal compositional flow mathematical model is developed. The phase transition diagram is designed according to the Minimum Miscibility Pressure (MMP and CO2 maximum solubility in oil phase. The convection and diffusion of CO2 mixtures in multiphase fluids in reservoirs, mass transfer between CO2 and crude and phase partitioning are considered. The governing equations are discretized by applying a fully implicit finite difference technique. Newton-Raphson iterative technique was used to solve the nonlinear equation systems and a simulator was developed. The performances of CO2 immiscible and miscible flooding in oil reservoirs are predicted by the new simulator. The distribution of pressure and temperature, phase saturations, mole fraction of each component in each phase, formation damage caused by asphaltene precipitation and the improved oil recovery are predicted by the simulator. Experimental data validate the developed simulator by comparison with simulation results. The applications of the simulator in prediction of CO2 flooding in oil reservoirs indicate that the simulator is robust for predicting CO2 flooding performance.

  19. Transdermal permeation of Zanthoxylum bungeanum essential oil on TCM components with different lipophilicity

    Directory of Open Access Journals (Sweden)

    Yi Lan

    2016-07-01

    Conclusion: Z. bungeanum oil facilitated transdermal permeation of drugs with different lipophilicity, including the extremely hydrophilic and lipophilic drugs, whereas it exhibited greater enhancement activity for strongly hydrophilic drugs. The mechanisms of transdermal permeation enhancement by the oil could be explained with SC/vehicle partition coefficient, saturation solubility, and the interactions with SC lipids.

  20. The optimal patch test concentration for ascaridole as a sensitizing component of tea tree oil

    NARCIS (Netherlands)

    Christoffers, Wietske Andrea; Bloemeke, Brunhilde; Coenraads, Pieter-Jan; Schuttelaar, Marie-Louise Anna

    2014-01-01

    BACKGROUND: Tea tree oil is used as a natural remedy, but is also a popular ingredient in household and cosmetic products. Oxidation of tea tree oil results in degradation products, such as ascaridole, which may cause allergic contact dermatitis. OBJECTIVES: To identify the optimal patch test concen

  1. A stochastic method for asphaltene structure formulation from experimental data: avoidance of implausible structures.

    Science.gov (United States)

    De León, Jennifer; Velásquez, Ana M; Hoyos, Bibian A

    2017-04-12

    This work presents a stochastic procedure designed to formulate a discrete set of molecular structures that, as a whole, adjust properly to experimental asphaltene data. This algorithm incorporates the pentane effect concept and Clar's sextet rule to the formulation process. The set of viable structures was constructed based on probability distribution functions obtained from experimental information and an isomer database containing all plausible configurations for a given number of rings, avoiding high-energy structures. This procedure was applied to a collection of experimental data from the literature. Ten sets, consisting of 5000 structures each, were obtained. Each set was then optimized. For the most accurate representation, four molecules were sufficient to properly reproduce the experimental input. The asphaltene system obtained is consistent with the reported molecular weight, number of aromatic rings and heteroatom content. Molecular dynamic simulations showed that the asphaltene representation adequately reproduced asphaltene aggregation behavior in toluene and n-heptane. In toluene, a single three-molecule aggregate was observed, and the majority of asphaltene molecules remained in a monomeric state. In n-heptane, aggregates containing up to four molecules were observed; both porous and compact aggregates were found. The asphaltene molecular representation obtained, which allows researchers to avoid inappropriate torsions in the molecule, is able to reproduce interplanar distances between aromatic cores of 4 Å or less for the aggregation state, as supported by experimental results.

  2. Chemistry and structure of coal derived asphaltenes and preasphaltenes. Quarterly progress report, April-June 1980

    Energy Technology Data Exchange (ETDEWEB)

    Yen, T. F.

    1980-01-01

    It is the objective of this project to isolate the asphaltene and preasphaltene fractions from coal liquids from a number of liquefaction processes. These processes consist of in general: catalytic hydrogenation, staged pyrolysis and solvent refining. These asphaltene fractions may be further separated by both gradient elution through column chromatography, and molecular size distribution through gel permeation chromatography. Those coal-derived asphaltene and preasphaltene fractions will be investigated by various chemical and physical methods for characterization of their structures. After the parameters are obtained, these parameters will be correlated with the refining and conversion variables which control a given type of liquefaction process. The effects of asphaltene in catalysis, ash or metal removal, desulfurization and denitrification will also be correlated. It is anticipated that understanding the role of asphaltenes in liquefaction processes will enable engineers to both improve existing processes, and to make recommendations for operational changes in planned liquefaction units in the United States. The objective of Phase 1 was to complete the isolation and separation of coal liquid fractions and to initiate their characterization. The objective of Phase 2 is to continue the characterization of coal asphaltenes and other coal liquid fractions by use of physical and instrumental methods. The structural parameters obtained will be used to postulate hypothetical average structures for coal liquid fractions. The objective of Phase 3 is to concentrate on the characterization of the preasphaltene (benzene insoluble fraction) of coal liquid fraction by the available physical and chemical methods to obtain a number of structural parameters.

  3. Presence of the Corexit component dioctyl sodium sulfosuccinate in Gulf of Mexico waters after the 2010 Deepwater Horizon oil spill

    Science.gov (United States)

    Gray, James L.; Kanagy, Leslie K.; Furlong, Edward T.; Kanagy, Chris J.; McCoy, Jeff W.; Mason, Andrew; Lauenstein, Gunnar

    2014-01-01

    Between April 22 and July 15, 2010, approximately 4.9 million barrels of oil were released into the Gulf of Mexico from the Deepwater Horizon oil well. Approximately 16% of the oil was chemically dispersed, at the surface and at 1500 m depth, using Corexit 9527 and Corexit 9500, which contain dioctyl sodium sulfosuccinate (DOSS) as a major surfactant component. This was the largest documented release of oil in history at substantial depth, and the first time large quantities of dispersant (0.77 million gallons of approximately 1.9 million gallons total) were applied to a subsurface oil plume. During two cruises in late May and early June, water samples were collected at the surface and at depth for DOSS analysis. Real-time fluorimetry data was used to infer the presence of oil components to select appropriate sampling depths. Samples were stored frozen and in the dark for approximately 6 months prior to analysis by liquid chromatography/tandem mass spectrometry with isotope-dilution quantification. The blank-limited method detection limit (0.25 μg L−1) was substantially less than the U.S. Environmental Protection Agency’s (USEPA) aquatic life benchmark of 40 μg L−1. Concentrations of DOSS exceeding 200 μg L−1 were observed in one surface sample near the well site; in subsurface samples DOSS did not exceed 40 μg L−1. Although DOSS was present at high concentration in the immediate vicinity of the well where it was being continuously applied, a combination of biodegradation, photolysis, and dilution likely reduced persistence at concentrations exceeding the USEPA aquatic life benchmark beyond this immediate area.

  4. Techniques for Determining Small Fractions of Oil Components in the Sea Water Flow by Rotation of Vibration Plane

    Directory of Open Access Journals (Sweden)

    Eric Mucunguzi-Rugwebe

    2013-09-01

    Full Text Available In this study, the results of the effect of water-flow rate and air fraction component on intensity, I, are presented and discussed. The study which was carried out at Bergen University in Norway, presents the impact of monochromatic defects on polarization and measurements of small oil fractions of various crude oils are presented. When there was refraction, it was observed that in static sea-water &mustatic = 0.38 and in running water &muflow = 0.42 When refraction was eliminated by grafting windows in the pipe, &mustatic = 0, &muflow = 0.11 and in both cases &muflow was independent of the flow rate. Air fraction component, &alpha> = 0.12 reduced light intensity. With rate flow Q = 13.6m3/h and Q = 27.2 m3/h critical air fraction was found at &alphac = 0.18 and &alphac = 0.12 respectively. For &alphac = 0.18 up to &alpha 0.87 at Q = 13.6m3/h and &alphac = 0.12 up to &alpha = 0.78 at Q = 27.2 m3/h light intensity was found independent of &alpha. The highest rotation was found in Gullfaks crude oil, followed by Heidrun, the rotation is Statfjord crude oil was less than one in Heidrun and the least rotation was observed in 0A sg 0a rd crude oil. At 40ppm, the rotation was as follows: Gullfaks &empty = 27.0±0.20, Heidrun &empty = 23.9±0.20, Statfjord &empty = 20.0±0.20 and 0Asg 0ard &empty = 10.0±0.10. This method studys very well when small oil fractions from 5.0-70 ppm are in sea-water flow. This technique can be deployed to monitor the environment and to control the re-injected process water.

  5. Presence of the Corexit component dioctyl sodium sulfosuccinate in Gulf of Mexico waters after the 2010 Deepwater Horizon oil spill.

    Science.gov (United States)

    Gray, James L; Kanagy, Leslie K; Furlong, Edward T; Kanagy, Chris J; McCoy, Jeff W; Mason, Andrew; Lauenstein, Gunnar

    2014-01-01

    Between April 22 and July 15, 2010, approximately 4.9 million barrels of oil were released into the Gulf of Mexico from the Deepwater Horizon oil well. Approximately 16% of the oil was chemically dispersed, at the surface and at 1500 m depth, using Corexit 9527 and Corexit 9500, which contain dioctyl sodium sulfosuccinate (DOSS) as a major surfactant component. This was the largest documented release of oil in history at substantial depth, and the first time large quantities of dispersant (0.77 million gallons of approximately 1.9 million gallons total) were applied to a subsurface oil plume. During two cruises in late May and early June, water samples were collected at the surface and at depth for DOSS analysis. Real-time fluorimetry data was used to infer the presence of oil components to select appropriate sampling depths. Samples were stored frozen and in the dark for approximately 6 months prior to analysis by liquid chromatography/tandem mass spectrometry with isotope-dilution quantification. The blank-limited method detection limit (0.25 μg L(-1)) was substantially less than the U.S. Environmental Protection Agency's (USEPA) aquatic life benchmark of 40 μg L(-1). Concentrations of DOSS exceeding 200 μg L(-1) were observed in one surface sample near the well site; in subsurface samples DOSS did not exceed 40 μg L(-1). Although DOSS was present at high concentration in the immediate vicinity of the well where it was being continuously applied, a combination of biodegradation, photolysis, and dilution likely reduced persistence at concentrations exceeding the USEPA aquatic life benchmark beyond this immediate area.

  6. Effect of source/sink ratios on yield components, growth dynamics and structural characteristics of oil palm (Elaeis guineensis) bunches.

    Science.gov (United States)

    Pallas, Benoît; Mialet-Serra, Isabelle; Rouan, Lauriane; Clément-Vidal, Anne; Caliman, Jean-Pierre; Dingkuhn, Michael

    2013-04-01

    Source/sink ratios are known to be one of the main determinants of oil palm growth and development. A long-term experiment (9 years) was conducted in Indonesia on mature oil palms subjected to continuous bunch ablation and partial defoliation treatments to artificially modify source/sink ratios. During the experiment, all harvested bunches were dissected and phenological measurements were carried out to analyse the effect of source/sink ratios on yield components explaining variations in bunch number, the number of fruits per bunch and oil dry weight per fruit. An integrative variable (supply/demand ratio) describing the ratio between the assimilate supply from sources and the growing organ demand for carbohydrate was computed for each plant on a daily basis from observations of the number of developing organs and their sink strength, and of climate variables. Defoliation and bunch ablation affected the bunch number and the fruit number per bunch. Variations in bunch number per month were mainly due to variations in the fraction of aborted inflorescence and in the ratio between female and male inflorescences. Under fluctuating trophic conditions, variations in fruit number per bunch resulted both from changes in fruit-set and in the number of branches (rachillae) per inflorescence. For defoliated plants, the decrease in the number of developing reproductive sinks appeared to be sufficient to maintain fruit weight and oil concentration at the control level, without any major decrease in the concentration of non-structural carbohydrate reserves. Computation of the supply/demand ratio revealed that each yield component had a specific phase of sensitivity to supply/demand ratios during inflorescence development. Establishing quantitative relationships between supply/demand ratios, competition and yield components is the first step towards a functional model for oil palm.

  7. The determination of maturity levels in source rocks of the La Luna Formation, Maracaibo Basin, Venezuela, based on convention geochemical parameters and asphaltenes; Determinacao do grau de maturacao em rochas geradoras de petroleo, formacao La Luna, Bacia de Maracaibo, Venezuela: parametros geoquimicos convencionais e asfaltenos

    Energy Technology Data Exchange (ETDEWEB)

    Castro, L.P. de [Pontificia Universidade Catolica (PUC-RS), Porto Alegre, RS (Brazil). Centro de Excelencia em Pesquisas sobre o Armazenamento de Carbono; Franco, N. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Dept. de Geologia; Lopez, L.; Lo Monaco, S.; Escobar, G. [Universidad Central de Venezuela (UCV), Caracas (Venezuela); Kalkreuth, W. [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Centro de Excelencia em Analises de Carvao e Rochas Geradoras de Petroleo

    2008-07-01

    The La Luna Formation, main source rock of the Maracaibo Basin was studied by conventional geochemical parameters, used to determine the maturity, and they were compared with the physic-chemical and molecular properties of the asphaltenes present in the bitumen of the rocks. Three wells were studied (A, B and C) with a total of 13 samples. Based on Rock-Eval results the organic matter in well A (455 deg C Tmax) shows a relatively high level of maturation (top of the oil window), whereas the organic matter in well B (435 - 436 deg C Tmax) is in the beginning of the oil window. Tmax values in well C (438 - 446 deg C) and well C suggest an intermediate maturity level. The biomarkers identified in well B and C show ratios indicating an equilibrium state in the maturity level. A good correlation was found comparing the conventional analytical data with the determination of maturity level obtained from the asphaltenes precipitated from the bitumen of the samples. With increased maturity levels the H1 NMR analysis showed enrichment in aromatic molecules in relation to aliphatic, due to the bitumen aromatization process. Similarly, the asphaltenes molecular weight has higher values in samples characterized by elevated maturity levels. This confirms earlier studies that showed that asphaltenes may be utilized as maturity parameter of organic matter. (author)

  8. Chemical and principal-component analyses of the essential oils of Apioideae taxa (Apiaceae) from central Balkan.

    Science.gov (United States)

    Kapetanos, Chrysostomos; Karioti, Anastasia; Bojović, Srdjan; Marin, Petar; Veljić, Milan; Skaltsa, Helen

    2008-01-01

    The volatile constituents of the essential oils of 23 taxa belonging to the Apioideae subfamily were studied in detail. The investigated taxa were Pimpinella serbica (Vis.) Bentham & Hooker, Libanotis montana Cr., Cnidium silaifolium (Jacq.) Simk. ssp. orientale (Boiss.) Tutin, Bupleurum praealtum L., B. sibthorpianum S. S. var. diversifolium (Roch.) Hay, Aegopodium podagraria L., Torilis anthriscus (L.) Gmel., Orlaya grandiflora (L.) Hoffm., Laserpitium siler L., Laser trilobum (L.) Brokh., Chaerophyllum aureum L., C. hirsutum L., C. temulum L., Pastinaca sativa L., P. hirsuta Pancic., Tordylium maximum L., Physospermum cornubiense (L.) DC., Peucedanum alsaticum L., P. oreoselinum (L.) Moench, P. cervaria (L.) Cuss., P. austriacum (Jacq.) Koch, P. longifolium W. et K., and P. officinale L. All of these species grow wild in the central part of the Balkan Peninsula. The essential oils were found to be complex mixtures of various compounds, more than 100 constituents being in each taxon, with contributions of main products never exceeding 25% of the total content. Sesquiterpene hydrocarbons were found to be the main group of constituents of all taxa, except for Peucedanum species, where monoterpene hydrocarbons were identified as the main components. The chemotaxonomic value of the essential-oil composition is discussed according to results of principal-component analysis (PCA). The essential-oil composition mainly reflects current taxonomic relationships between the investigated taxa.

  9. Antibacterial activity and anticancer activity of Rosmarinus officinalis L. essential oil compared to that of its main components.

    Science.gov (United States)

    Wang, Wei; Li, Nan; Luo, Meng; Zu, Yuangang; Efferth, Thomas

    2012-03-05

    In this study, Rosmarinus officinalis L. essential oil and three of its main components 1,8-cineole (27.23%), α-pinene (19.43%) and β-pinene (6.71%) were evaluated for their in vitro antibacterial activities and toxicology properties. R. officinalis L. essential oil possessed similar antibacterial activities to α-pinene, and a little bit better than β-pinene, while 1,8-cineole possessed the lowest antibacterial activities. R. officinalis L. essential oil exhibited the strongest cytotoxicity towards three human cancer cells. Its inhibition concentration 50% (IC₅₀) values on SK-OV-3, HO-8910 and Bel-7402 were 0.025‰, 0.076‰ and 0.13‰ (v/v), respectively. The cytotoxicity of all the test samples on SK-OV-3 was significantly stronger than on HO-8910 and Bel-7402. In general, R. officinalis L. essential oil showed greater activity than its components in both antibacterial and anticancer test systems, and the activities were mostly related to their concentrations.

  10. Crude oil price forecasting based on hybridizing wavelet multiple linear regression model, particle swarm optimization techniques, and principal component analysis.

    Science.gov (United States)

    Shabri, Ani; Samsudin, Ruhaidah

    2014-01-01

    Crude oil prices do play significant role in the global economy and are a key input into option pricing formulas, portfolio allocation, and risk measurement. In this paper, a hybrid model integrating wavelet and multiple linear regressions (MLR) is proposed for crude oil price forecasting. In this model, Mallat wavelet transform is first selected to decompose an original time series into several subseries with different scale. Then, the principal component analysis (PCA) is used in processing subseries data in MLR for crude oil price forecasting. The particle swarm optimization (PSO) is used to adopt the optimal parameters of the MLR model. To assess the effectiveness of this model, daily crude oil market, West Texas Intermediate (WTI), has been used as the case study. Time series prediction capability performance of the WMLR model is compared with the MLR, ARIMA, and GARCH models using various statistics measures. The experimental results show that the proposed model outperforms the individual models in forecasting of the crude oil prices series.

  11. Crude Oil Price Forecasting Based on Hybridizing Wavelet Multiple Linear Regression Model, Particle Swarm Optimization Techniques, and Principal Component Analysis

    Directory of Open Access Journals (Sweden)

    Ani Shabri

    2014-01-01

    Full Text Available Crude oil prices do play significant role in the global economy and are a key input into option pricing formulas, portfolio allocation, and risk measurement. In this paper, a hybrid model integrating wavelet and multiple linear regressions (MLR is proposed for crude oil price forecasting. In this model, Mallat wavelet transform is first selected to decompose an original time series into several subseries with different scale. Then, the principal component analysis (PCA is used in processing subseries data in MLR for crude oil price forecasting. The particle swarm optimization (PSO is used to adopt the optimal parameters of the MLR model. To assess the effectiveness of this model, daily crude oil market, West Texas Intermediate (WTI, has been used as the case study. Time series prediction capability performance of the WMLR model is compared with the MLR, ARIMA, and GARCH models using various statistics measures. The experimental results show that the proposed model outperforms the individual models in forecasting of the crude oil prices series.

  12. Far- and mid-infrared spectroscopy of complex organic matter of astrochemical interest: coal, heavy petroleum fractions and asphaltenes

    Science.gov (United States)

    Cataldo, Franco; García-Hernández, D. A.; Manchado, Arturo

    2013-03-01

    The coexistence of a large variety of molecular species (i.e. aromatic, cycloaliphatic and aliphatic) in several astrophysical environments suggests that unidentified infrared emission (UIE) occurs from small solid particles containing a mix of aromatic and aliphatic structures (e.g. coal, petroleum, etc.), renewing the astronomical interest on this type of materials. A series of heavy petroleum fractions namely `distillate aromatic extract', `Residual Aromatic Extract', heavy aromatic fraction (BQ-1) and asphaltenes derived from BQ-1 were used together with anthracite coal and bitumen as model compounds in matching the band pattern of the emission features of proto-planetary nebulae (PPNe). All the model materials were examined in the mid-infrared (2.5-16.66 μm) and for the first time in the far-infrared (16.66-200 μm), and the infrared bands were compared with the UIE from PPNe. The best match of the PPNe band pattern is offered by the BQ-1 heavy aromatic oil fraction and by its asphaltenes fraction. Particularly interesting is the ability of BQ-1 to match the band pattern of the aromatic-aliphatic C-H stretching bands of certain PPNe, a result which is not achieved neither by the coal model nor by the other petroleum fractions considered here. This study shows that a new interesting molecular model of the emission features of PPNe is asphaltene molecules which are composed by an aromatic core containing three to four condensed aromatic rings surrounded by cycloaliphatic (naphtenic) and aliphatic alkyl chains. Instead, the weakness of the model involving a mixture of polycyclic aromatic hydrocarbons (PAHs) for modelling the aromatic infrared emission bands (AIBs) is shown. The laboratory spectra of these complex organic compounds represent a unique data set of high value for the astronomical community, e.g. they may be compared with the Herschel Space Observatory spectra (˜51-220 μm) of several astrophysical environments such as (proto-) planetary nebulae, H

  13. Component

    Directory of Open Access Journals (Sweden)

    Tibor Tot

    2011-01-01

    Full Text Available A unique case of metaplastic breast carcinoma with an epithelial component showing tumoral necrosis and neuroectodermal stromal component is described. The tumor grew rapidly and measured 9 cm at the time of diagnosis. No lymph node metastases were present. The disease progressed rapidly and the patient died two years after the diagnosis from a hemorrhage caused by brain metastases. The morphology and phenotype of the tumor are described in detail and the differential diagnostic options are discussed.

  14. 沥青质临氢热裂化转化规律初步研究%Preliminary Investigation on Behaviors of Thermal Conversion of Asphaltene in the Presence of Hydrogen and Catalyst

    Institute of Scientific and Technical Information of China (English)

    董明; 龙军; 王子军; 侯焕娣; 王威

    2015-01-01

    The asphaltene structure of Tahe VR was studied by using APPI + FT-ICR MS ,XPS et al .The behaviors of thermal conversion of Tahe VR asphaltene in the presence of hydrogen and catalyst were investigated .The results showed that the thermal conversion process was dominated by thermal cracking ,and the catalyst inhibited the condensation of asphaltene and hydrogenate aromatic rings to promote the conversion of asphaltene . In the appropriate conditions , the asphaltene conversion rate of Tahe VR reached 85.8% ,and cracking rate 78.2% .The conversion of secondary asphaltene was the key for the conversion of asphaltene . It is difficult for the condensed aromatics and N-heterocycle aromatics in the secondary asphaltene of Tahe VR to convert ,and conversion difficulties of HC (aromatic) ,N1 (N-heterocycle containing one N atom ) , N2 (N-heterocycle containing two N atoms) decreased in turn .The components of asphaltene with sulfur and two or more than two different heteroatoms were easier to convert .The hydrogenation reaction is the key for asphaltene upgrading .%运用APPI+结合FT-ICR MS、XPS等方法分析塔河沥青质结构。以塔河减压渣油为原料研究沥青质的临氢热裂化转化规律。结果表明,沥青质临氢热裂化过程中的裂化反应以热裂化为主,催化剂可以抑制沥青质的缩合反应,并对沥青质中芳环结构加氢以促进其转化。在合适的条件下,塔河减压渣油沥青质转化率可以达到85.8%,裂化率达到78.2%。次生沥青质的转化是沥青质转化的关键,次生沥青质中最难转化的是稠环芳烃结构和氮稠环结构,其转化难度按从难到易的顺序为 HC(芳烃结构)、N1(含1个氮原子的芳香性氮化物结构)、N2(含2个氮原子的芳香性氮化物结构)。含硫结构以及含有2种或多于2种杂原子的沥青质结构的转化率较高。加氢反应是沥青质轻质化的关键。

  15. [Evaluation on contribution rate of each component total salvianolic acids and characterization of apparent oil/water partition coefficient].

    Science.gov (United States)

    Yan, Hong-mei; Chen, Xiao-yun; Xia, Hai-jian; Liu, Dan; Jia, Xiao-bin; Zhang, Zhen-hai

    2015-02-01

    The difference between three representative components of total salvianolic acids in pharmacodynamic activity were compared by three different pharmacological experiments: HUVECs oxidative damage experiment, 4 items of blood coagulation in vitro experiment in rabbits and experimental myocardial ischemia in rats. And the effects of contribution rate of each component were calculated by multi index comprehensive evaluation method based on CRITIC weights. The contribution rates of salvianolic acid B, rosmarinic acid and Danshensu were 28.85%, 30.11%, 41.04%. Apparent oil/water partition coefficient of each representative components of total salvianolic acids in n-octyl alcohol-buffer was tested and the total salvianolic acid components were characterized based on a combination of the approach of self-defined weighting coefficient with effects of contribution rate. Apparent oil/water partition coefficient of total salvianolic acids was 0.32, 1.06, 0.89, 0.98, 0.90, 0.13, 0.02, 0.20, 0.56 when in octanol-water/pH 1.2 dilute hydrochloric acid solution/ pH 2.0, 2.5, 5.0, 5.8, 6.8, 7.4, 7.8 phosphate buffer solution. It provides a certain reference for the characterization of components.

  16. EPR and EOM studies in well samples from some Venezuelan oil fields: possible mechanisms of magnetic authigenesis

    Science.gov (United States)

    Aldana, M.; Díaz, M.; Costanzo-Alvarez, V.; Jiménez, S. M.; Sequera, P.

    2003-04-01

    In the last few years we have conducted Electron Paramagnetic Resonance (EPR) and Magnetic Susceptibility (MS) studies in drilling fines, from near-surface levels, from producer and non-producer wells. These studies were aimed at examining a possible causal relationship between magnetic contrasts and underlying hydrocarbons. In this work we have extended these studies to some new wells, trying to identify the possible origin (microbial and/or thermochemical) of the observed anomalies. Together with EPR and MS studies, quantification of extractable organic matter (EOM) has been also performed. The samples were pulverized and split into two aliquots. One aliquot was treated with chloroform in order to separate de EOM and obtain the sample without EOM and the EOM itself. The other aliquot was not solvent extracted. The EOM was quantified and EPR measurements were performed on both aliquots in order to determine the organic matter free radical concentration (OMFRC). The treatments performed allow identifying whether the OMFRC belongs to the EOM or to the total organic matter (TOM). Asphaltenes tend to be the major components in highly biodegraded crude oils. Then the presence of OMFRC belonging to the TOM or to the EOM could indicate a possible microbial or thermochemical origin, respectively, of the detected MS anomalies. We have found OMFRC and EOM anomalies only at the producer wells, in the same zone where MS anomalies, associated with the presence of spherical aggregates of magnetic minerals, were observed. For some of these wells our results indicate the solely presence of free radicals of kerogen at OMFRC anomalous level. In fact, the EOM of these wells has no EPR signal and precipitation of asphaltene in n-heptane was not observed. In other instances, free radicals of kerogen and asphaltenes and precipitation of asphaltene from the EOM in n-heptane was observed. In the former case we suggest the existence of a reducing zone where thermochemical conditions are

  17. [Component analysis and acute hepatotoxicity of volatile oils from argy wormwood leaf extracted by different methods].

    Science.gov (United States)

    Liu, Hongjie; Bai, Yang; Hong, Yanlong; Zhang, Xun

    2010-06-01

    To analyze the chemical composition and compare acute hepatotoxicity of essential oils extracted from argy wormwood leaf in Guangdong by four different methods. Four extraction methods, including hydrodistillation extraction, supercritical fluid CO2 extraction, petroleum ether ultrasonic extraction and petroleum ether microwave extraction, were employed to prepare essential oil from argy wormwood leaf in Guangdong. The products were analyzed qualitatively and quantitatively using GC-MS and GC-FID. Sixty mice were divided into 5 groups according to different essential oils and took the same dose orally, then after 5 hours, hepatic functional parameters in serum were detected such as alanine aminotransferase (ALT) and so on, and morphologic change of hepatic tissues was observed. The extraction rate of the four methods and identified compounds was 1.02%, 80 (hydrodistillation extraction), 2.46%, 56 (supercritical fluid CO2 extraction), 3.17%, 45 (petroleum ether ultrasonic extraction) and 3.32%, 78 (petroleum ether microwave extraction) respectively. Totally 153 compounds were identified from those essential oils. Compared with that of the control group, some hepatic functional parameters of hydrodistillation and supercritical fluid CO2 extraction groups rose significantly (P extracted from argy wormwood leaf by different methods may have not only different chemical composition, but also different acute hepatotoxicity, and monoterpenes and benzenes in the essential oils might induce acute hepatotoxicity.

  18. Hydroxytyrosol extracts, olive oil and walnuts as functional components in chicken sausages.

    Science.gov (United States)

    Nieto, Gema; Martínez, Lorena; Castillo, Julian; Ros, Gaspar

    2017-08-01

    Olive oil, hydroxytyrosol and walnut can be considered ideal Mediterranean ingredients for their high polyphenolic content and healthy properties. Three extracts of hydroxytyrosol obtained using different extraction processes (HXT 1, 2, 3) (50 ppm) were evaluated for use as antioxidants in eight different chicken sausage formulas enriched in polyunsaturated fatty acids (2.5 g 100 g(-1) walnut) or using extra virgin olive oil (20 g 100 g(-1) ) as fat replacer. Lipid and protein oxidation, colour, emulsion stability, and the microstructure of the resulting chicken sausages were investigated and a sensory analysis was carried out. The sausages with HXT extracts were found to decrease lipid oxidation and to lead to the loss of thiol groups compared with control sausages. Emulsion stability (capacity to hold water and fat) was greater in the sausages containing olive oil and walnut than in control sausages. In contrast, the HXT extracts produced high emulsion instability (increasing cooking losses). Sensory analysis suggested that two of the HXT extracts studied (HXT2 and HXT3 ) were unacceptable, while the acceptability of the other was similar to that of the control products. Sausages incorporating HXT showed different structures than control samples or sausages with olive oil, related to the composition of the emulsion. These results suggest the possibility of replacing animal fat by olive oil and walnut in order to produce healthy meat products. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  19. [Comparison of Chemical Components of Essential Oil from Ocimum basilicum var. pilosum Extracted by Supercritical CO2 Fluid and Steam Distillation].

    Science.gov (United States)

    Wang, Zhao-yu; Zheng, Jia-huan; Shi, Sheng-ying; Luo, Zhi-xiong; Ni, Shun-yu; Lin, Jing-ming

    2015-11-01

    To compare the chemical components of essential oil prepared by steam distillation extraction (SD) and supercritical CO2 fluid extraction (SFE-CO2) from Ocimum basilicum var. pilosum whole plant. The essential oil of Ocimum basilicum var. pilosum were extracted by SD and SFE-CO2. The chemical components of essential oil were separated and analyzed by gas chromatography-mass spectrometry( GC-MS). Their relative contents were determined by normalization of peak area. 40 and 42 compounds were detected in the essential oil prepared by SD and SFE-CO2 respectively. 25 compounds were common. Thereare significant differences of the chemical components between the Ocimum basilicum var. pilosum essential oil prepared by SD and thatby SFE-CO2. Different methods showed different extraction efficiency with a special compound. It might be a good idea to unite several methods in the modern traditional Chinese medicine industry.

  20. Stabilization of Model Crude Oil Emulsion using Different ...

    African Journals Online (AJOL)

    MBI

    2015-12-31

    Dec 31, 2015 ... from treated Ondo State oil sand bitumen with n-hexane in a 40:1 solvent to bitumen ratio .... Table 1: Volume of water resolved for 0.05 % asphaltene stabilized emulsion per time ... (Table 4), there was a drop in the degree of.

  1. Sedative effect of central administration of Coriandrum sativum essential oil and its major component linalool in neonatal chicks.

    Science.gov (United States)

    Gastón, María Soledad; Cid, Mariana Paula; Vázquez, Ana María; Decarlini, María Florencia; Demmel, Gabriela I; Rossi, Laura I; Aimar, Mario Leandro; Salvatierra, Nancy Alicia

    2016-10-01

    Context Coriandrum sativum L. (Apiaceae) (coriander) is an herb grown throughout the world as a culinary, medicinal or essential crop. In traditional medicine, it is used for the relief of anxiety and insomnia. Systemic hydro-alcoholic and aqueous extract from aerial parts and seeds had anxiolytic and sedative action in rodents, but little is known about its central effect in chicks. Objective To study the effects of intracerebroventricular administration of essential oil from coriander seeds and its major component linalool on locomotor activity and emotionality of neonatal chicks. Materials and methods The chemical composition of coriander essential oil was determined by a gas-chromatographic analysis (> 80% linalool). Behavioural effects of central administration of coriander oil and linalool (both at doses of 0.86, 8.6 and 86 μg/chick) versus saline and a sedative diazepam dose (17.5 μg/chick, standard drug) in an open field test for 10 min were observed. Results Doses of 8.6 and 86 μg from coriander oil and linalool significantly decreased (p Coriandrum sativum seeds induced a sedative effect at 8.6 and 86 μg doses. This effect may be due to monoterpene linalool, which also induced a similar sedative effect, and, therefore, could be considered as a potential therapeutic agent similar to diazepam.

  2. Optical fiber extrinsic refractometer to measure RI of samples in a high pressure and temperature systems: Application to wax and asphaltene precipitation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Jimmy Castillo; Carlos Canelon; Socrates Acevedo; Herve Carrier; Jean-Luc Daridon [Universidad Central de Venezuela, Caracas (Venezuela). Facultad de Ciencias, Escuela de Quimica

    2006-10-15

    An optical fiber extrinsic sensor for measurement of changes in the refractive index of liquids confined in chambers for high pressure and temperature experiments is described. One head sensor composed by two fibers is fixed in front of a high pressure and temperature cell filled with the sample. The operation principle is based in the reflectivity dependence in the refractive index of the glass-liquid interface. Excellent results and a sensitivity of 10{sup -5} RI were obtained for pure liquids. The applicability of the sensor is demonstrated following the changes in the refractive index for pure liquids at different pressure and temperatures and by measuring the asphaltenes and wax precipitation in crude oils under pressure. The extrinsic probe designed for refractive index measurement proves to be a reliable tool for measuring heavy organics deposition in crude oils under high pressures and temperatures where the sample to be measured is not very accessible. 25 refs., 11 figs., 2 tabs.

  3. Analysis of lemon essential oil activity component%柠檬精油的活性成分分析

    Institute of Scientific and Technical Information of China (English)

    李一帆; 杨晨; 徐金勇; 李光武

    2013-01-01

    目的 通过GC/MS分析LEO的活性成分.方法 将LEO溶于正己烷,配成2%的溶液,每次进样1 μL,流经DB-5毛细管柱,采用GC/MS技术并与NIST标准谱库进行比对确定LEO中各化学成分,按峰面积归一化法得出各组分百分含量.结果 GC/MS分析发现LEO的12种化学成分,占总LEO含量的98.85%,其中含量最高的是m-Mentha-6,8-diene,(R)-(+)-达到77.04%,其次为-Terpinen占14.90%.结论 该试验建立的方法 简便、快捷、准确,可为EO检测的标准操作流程提供参考,并为建立精油指纹图谱库提供可能.%Objective Analysis of lemon essential oil aetivity component by GC/MS. Methods Gas chromatograph fitted with a DB-5 capillary column;volume injected, 1 μL of lemon essential oil in n-hexane( 2% ). The identification of compounds was based on direct comparison of the mass spectral data with those for the standards and by computer matching with the NIST Library. Component percentage obtains by peak area normalization method. Results The GC-MS analysis of the lemon essential oil led to the identification and quantification of approximately 12 main compounds,which accounted for 98. 85% of the total components present. M-Mentha-6 ,8-diene,( R )-( + )-( 77.04% ) was the principal component followed by c-Terpinen( 14.90% ). Conclusion The method is convenient,fast and accurate which can become essential oils detection standard operating procedure and provide the possibility to establish fingerprint library of essential oils.

  4. Identification of components in fast pyrolysis oil and upgraded products by comprehensive two-dimensional gas chromatography and flame ionisation detection

    NARCIS (Netherlands)

    Marsman, J.H.; Wildschut, J.; Mahfud, F.; Heeres, H.J.

    2007-01-01

    Pyrolysis oil and upgraded products are promising energy carriers. Characterisation of the oils is hampered due to the presence of a large number of components (>400) belonging to a broad variety of chemical compound classes (i.e., acids, aldehydes, ketones). In this study, a comparison of the capab

  5. Identification of components in fast pyrolysis oil and upgraded products by comprehensive two-dimensional gas chromatography and flame ionisation detection

    NARCIS (Netherlands)

    Marsman, J.H.; Wildschut, J.; Mahfud, F.; Heeres, H.J.

    2007-01-01

    Pyrolysis oil and upgraded products are promising energy carriers. Characterisation of the oils is hampered due to the presence of a large number of components (>400) belonging to a broad variety of chemical compound classes (i.e., acids, aldehydes, ketones). In this study, a comparison of the

  6. Kinetics of coffee industrial residue pyrolysis using distributed activation energy model and components separation of bio-oil by sequencing temperature-raising pyrolysis.

    Science.gov (United States)

    Chen, Nanwei; Ren, Jie; Ye, Ziwei; Xu, Qizhi; Liu, Jingyong; Sun, Shuiyu

    2016-12-01

    This study was carried out to investigate the kinetics of coffee industrial residue (CIR) pyrolysis, the effect of pyrolysis factors on yield of bio-oil component and components separation of bio-oil. The kinetics of CIR pyrolysis was analyzed using distributed activation energy model (DAEM), based on the experiments in thermogravimetric analyzer (TGA), and it indicated that the average of activation energy (E) is 187.86kJ·mol(-1). The bio-oils were prepared from CIR pyrolysis in vacuum tube furnace, and its components were determined by gas chromatography/mass spectrometry (GC-MS). Among pyrolysis factors, pyrolysis temperature is the most influential factor on components yield of bio-oil, directly concerned with the volatilization and yield of components (palmitic acid, linoleic acid, oleic acid, octadecanoic acid and caffeine). Furthermore, a new method (sequencing temperature-raising pyrolysis) was put forward and applied to the components separation of bio-oil. Based on experiments, a solution of components separation of bio-oil was come out.

  7. From aggregation to flocculation of asphaltenes, a structural description by radiation scattering techniques; De l'agregation a la floculation des asphaltenes, une description structurale par diffusion de rayonnement

    Energy Technology Data Exchange (ETDEWEB)

    Fenistein, D.; Barre, L.; Frot, D. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France)

    2000-02-01

    The study, using radiation scattering techniques (X-rays, neutrons, light) of asphaltenes in toluene and heptane mixtures, reveals their structure of aggregation versus the heptane/toluene ratio. In a solvent containing little heptane, the aggregates of asphaltenes are fractal and solvated. Their kinetics of aggregation is compatible with the forecasts model of aggregation RLCA (Reaction Limited Cluster Aggregation). For higher proportions of heptane the asphaltenes arrange in compact structures of very big sizes. We associate this transition, between a solvated aggregation and a compaction process, to the asphaltene flocculation phenomenon. The study, using the very small angle X-ray scattering technique, of the Safaniya vacuum residue shows that these compact asphaltene aggregates may exist in some industrial fluids. (authors)

  8. Surface chemistry and spectroscopy of UG8 asphaltene Langmuir film, part 2.

    Science.gov (United States)

    Orbulescu, Jhony; Mullins, Oliver C; Leblanc, Roger M

    2010-10-05

    While there has been much focus on asphaltenes in toluene, there has been much less focus on asphaltenes in other solvents. It is important to quantify characteristics of asphaltenes in solvents besides toluene in order to better assess their molecular architecture as well as their fundamental aggregation characteristics. The present work focuses on the investigation of UG8 asphaltene Langmuir films at the air-water interface using chloroform as spreading solvent. The results are compared to the results recently obtained using toluene as spreading solvent. Surface pressure-area isotherms and UV-vis spectroscopy indicate that asphaltenes form smaller nanoaggregates in chloroform than in toluene in similar concentration ranges. Still these nanoaggreates share common features with those in toluene. From the surface pressure-area and compression-decompression isotherms, Brewster angle microscopy, and p-polarized infrared reflection-absorption spectroscopy, it was concluded that small size aggregates are spread on the water surface and the compression of the film leads to formation of large aggregates. The films (Langmuir-Schaefer and Langmuir-Blodgett) studied by atomic force microscopy reveal the existence of nanoaggregates spread on the water surface that coexist with large aggregates formed during compression. In addition to these findings, the spreading solvent, chloroform, allows the determination of asphaltene absorption bands using in situ UV-vis spectroscopy at the air-water interface after 15 min waiting time period. The absorbance data carried out after waiting a time period of 1 h shows similar features with the ones carried out after only 15 min; therefore, there is no need to wait 1 h as in the case when toluene is used as spreading solvent. A comparison of the data obtained from chloroform and toluene shows that smaller aggregate sizes are obtained from chloroform as suggested from the surface pressure-area isotherm, in situ UV-vis spectroscopy, and

  9. Studies on water-in-oil products from crude oils and petroleum products.

    Science.gov (United States)

    Fingas, Merv; Fieldhouse, Ben

    2012-02-01

    Water-in-oil mixtures such as emulsions, often form and complicate oil spill countermeasures. The formation of water-in-oil mixtures was studied using more than 300 crude oils and petroleum products. Water-in-oil types were characterized by resolution of water at 1 and 7 days, and some after 1 year. Rheology measurements were carried out at the same intervals. The objective of this laboratory study was to characterize the formed water-in-oil products and relate these properties to starting oil properties. Analysis of the starting oil properties of these water-in-oil types shows that the existence of each type relates to the starting oil viscosity and its asphaltene and resin contents. This confirms that water-in-oil emulsification is a result of physical stabilization by oil viscosity and chemical stabilization by asphaltenes and resins. This stabilization is illustrated using simple graphical techniques. Four water-in-oil types exist: stable, unstable, meso-stable and entrained. Each of these has distinct physical properties. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Differential Cytotoxicity of MEX: a Component of Neem Oil Whose Action Is Exerted at the Cell Membrane Level

    Directory of Open Access Journals (Sweden)

    Francesca Ricci

    2008-12-01

    Full Text Available Neem oil is obtained from the seeds of the tree Azadirachta indica. Its chemical composition is very complex, being rich in terpenoids and limonoids, as well as volatile sulphur modified compounds. This work focused on the evaluation of a component of the whole Neem oil obtained by methanolic extraction and defined as MEX. Cytotoxicity was assessed on two different cell populations: a stabilized murine fibroblast line (3T6 and a tumor cell line (HeLa. The data presented here suggest a differential sensitivity of these two populations, the tumor line exhibiting a significantly higher sensitivity to MEX. The data strongly suggest that its toxic target is the cell membrane. In addition the results presented here imply that MEX may contain one or more agents that could find a potential use in anti-proliferative therapy.

  11. Chemical structure of asphaltenes from tar produced in semicoking of lignite from the Kansk-Achinsk fields (Berezovka deposit)

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Proskuryakov, V.A.; Ryltsova, S.V.; Klyavina, O.A. [Lev Tolstoi State Pedagogical University, Tula (Russian Federation)

    1998-10-01

    The chemical composition of asphaltenes from semicoking tar recovered at 450-600{degree}C from Kansk-Achinsk lignite was studied by a set of physicochemical methods. A liquid adsorption chromatographic scheme was developed for separation of asphaltenes into a large number of subfractions significantly differing in the structural parameters and in the nature and content of functional groups.

  12. Isothermal Titration Calorimetry and Fluorescence Spectroscopy Study Of Asphaltene Self-Association In Toluene And Interaction With A Model Resin

    DEFF Research Database (Denmark)

    Garcia, Daniel Merino; Andersen, Simon Ivar

    2002-01-01

    This article collects the work performed by Isothermal Titration Caloritnetry (ITC) in the study of the self-association of asphaltenes in toluene solutions. Calorimetric experiments show that asphaltenes, start self-associating at very low concentrations and that the existence of a Critical Mice...

  13. Molecular Dynamics Simulation to Investigate the Interaction of Asphaltene and Oxide in Aggregate

    Directory of Open Access Journals (Sweden)

    Rui Li

    2016-01-01

    Full Text Available The asphalt-aggregate interface interaction (AAI plays a significant role in the overall performances of asphalt mixture, which is caused due to the complicated physicochemical processes and is influenced by various factors, including the acid-base property of aggregates. In order to analyze the effects of the chemical constitution of aggregate on the AAI, the average structure C65H74N2S2 is selected to represent the asphaltene in asphalt and magnesium oxide (MgO, calcium oxide (CaO, aluminium sesquioxide (Al2O3, and silicon dioxide (SiO2 are selected to represent the major oxides in aggregate. The molecular models are established for asphaltene and the four oxides, respectively, and the molecular dynamics (MD simulation was conducted for the four kinds of asphaltene-oxide system at different temperatures. The interfacial energy in MD simulation is calculated to evaluate the AAI, and higher value means better interaction. The results show that interfacial energy between asphaltene and oxide reaches the maximum value at 25°C and 80°C and the minimum value at 40°C. In addition, the interfacial energy between asphaltene and MgO was found to be the greatest, followed by CaO, Al2O3, and SiO2, which demonstrates that the AAI between asphalt and alkaline aggregates is better than acidic aggregates.

  14. Hindered diffusion of asphaltenes at elevated temperature and pressure. Semiannual report, March 20 - September 20, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Guin, J.A.; Geelen, R.; Gregory, C.; Yang, X.

    1996-11-01

    The objectives are to: investigate the hindered diffusion of coal and petroleum asphaltenes in the pores of catalyst particles at elevated temperature and pressures; and examine the effects of concentration, temperature, solvent type, and pressure on the intraparticle diffusivity of asphaltenes. Progress was made in several areas during this time period. The high temperature/high pressure autoclave has been received from Parr Instrument Company and is in the process of being set up and checked out. During this time period we mainly worked in two areas. In the first area, we performed some measurements on the adsorption isotherms of the model compound quinoline in cyclohexane onto a Criterion 324 catalyst at three temperatures. We are looking at the effect of temperature on the adsorption isotherms of several model compounds. This area is important since the adsorptive uptake of asphaltenes is being studied and the model compound systems lend insight as to how we may expect the more complex asphaltene systems to behave during adsorption on the surface of the porous particles. We found that even for the simple model compound quinoline, the adsorption behavior vs. temperature was quite 0563 complex. The second area explored during this time period was the application of a mathematical model to adsorptive uptake data for asphaltenes on Criterion 324 catalyst particles. This adsorptive uptake data was obtained during the previous time period and was analyzed by mathematical modeling during the current time period. The detailed findings in both of these areas are presented in this report.

  15. Variability in biochemical components of the mussel (Mytilus galloprovincialis) cultured after Prestige oil spill.

    Science.gov (United States)

    Peteiro, Laura G; Labarta, Uxío; Fernández-Reiriz, María José

    2007-05-01

    The biochemical composition (proteins, carbohydrates, glycogen, total lipids and lipid classes) of the mussel Mytilus galloprovincialis was investigated during an experimental culture using mussel seed from areas with different degree of exposure to the Prestige oil spill. The aim of the study was to identify alterations in the biochemical composition of mussel seed from natural populations commonly used in Galicia for mussel raft culture that might be linked to previous oil exposure. We have selected three mussel seed populations from Pindo, Miranda and Redes, that were characterised in a previous study according to the oil exposure three months after the spill. These populations were transplanted to a raft culture system in the Ría de Ares-Betanzos where our experimental culture followed standard commercial techniques from March 2003 to February 2004. Mussels from Pindo (characterised as the most affected area by the oil spill) showed marked differences in lipid composition with regard to other populations in the content of triacylglycerols, (PRedes (designed as reference area) which may reflect that Miranda mussels were not affected or only hardly affected by the spill. With the exception of the onset of the culture, biochemical composition showed similar patterns in all mussel populations. Then, the fact of being cultured in a common environment seemed to be more responsible for the long-term variability in the energetic reserve than the origin of the populations or their previous biochemical status.

  16. Molecular interactions of plant oil components with stratum corneum lipids correlate with clinical measures of skin barrier function.

    Science.gov (United States)

    Mack Correa, Mary Catherine; Mao, Guangru; Saad, Peter; Flach, Carol R; Mendelsohn, Richard; Walters, Russel M

    2014-01-01

    Plant-derived oils consisting of triglycerides and small amounts of free fatty acids (FFAs) are commonly used in skincare regimens. FFAs are known to disrupt skin barrier function. The objective of this study was to mechanistically study the effects of FFAs, triglycerides and their mixtures on skin barrier function. The effects of oleic acid (OA), glyceryl trioleate (GT) and OA/GT mixtures on skin barrier were assessed in vivo through measurement of transepidermal water loss (TEWL) and fluorescein dye penetration before and after a single application. OA's effects on stratum corneum (SC) lipid order in vivo were measured with infrared spectroscopy through application of perdeuterated OA (OA-d34 ). Studies of the interaction of OA and GT with skin lipids included imaging the distribution of OA-d34 and GT ex vivo with IR microspectroscopy and thermodynamic analysis of mixtures in aqueous monolayers. The oil mixtures increased both TEWL and fluorescein penetration 24 h after a single application in an OA dose-dependent manner, with the highest increase from treatment with pure OA. OA-d34 penetrated into skin and disordered SC lipids. Furthermore, the ex vivo IR imaging studies showed that OA-d34 permeated to the dermal/epidermal junction while GT remained in the SC. The monolayer experiments showed preferential interspecies interactions between OA and SC lipids, while the mixing between GT and SC lipids was not thermodynamically preferred. The FFA component of plant oils may disrupt skin barrier function. The affinity between plant oil components and SC lipids likely determines the extent of their penetration and clinically measurable effects on skin barrier functions. © 2013. Johnson & Johnson Consumer Companies Inc.. Experimental Dermatology published by John Wiley & Sons Ltd.

  17. The essential oil components of Cinnamomum cassia:an analysis under different thinning models of plantation Pinus massoniana

    Institute of Scientific and Technical Information of China (English)

    Dayan Tao; Yuanfa Li; Daodiao Lu; Yehong Luo; Sufang Yu; Shaoming Ye

    2016-01-01

    Thinning is an important activity employed in forest management. To date, studies have mainly focused on the effects of thinning on the growth of trees during the same thinning period. In this study, plantation Pinus mas-soniana Lamb. near maturity were thinned at varying intensities and an economically important species, Cin-namomum cassia Presl., was planted beneath the thinned canopy. The aim of the study was to explore the effects of the extent of thinning on the essential oil content and its components of C. cassia in different parts of the plant, as well as the economic feasibility of the P. massoniana–C. cassia management model. Thinning significantly reduced the oil yield in the bark and branches of C. cassia, but hardly impacted the oil yield from C. cassia leaves com-pared with pure C. cassia forest (CK). Among the different thinning treatments, both light (T.4) and extensive (T.1) thinning reduced the oil yield of C. cassia bark and new branches. The concentrations of the main aldehydes differed in different parts of the plant and were affected by the extent of thinning. The influence on cinnamaldehyde in the bark was minor, but was much greater in the branches and leaves. Both the oil yield and content of cinnamalde-hyde showed that moderate (T.3) thinning was more favorable than other thinning models. These results not only provide a potentially promising model for the trans-formation of low–yield artificial pure forests of P. masso-niana in the future, but also offer a reference for the management of artificial mixed stands.

  18. Effect of the structure of commercial poly(ethylene oxide-b-propylene oxide) demulsifier bases on the demulsification of water-in-crude oil emulsions: elucidation of the demulsification mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Ramalho, Joao Batista V.S. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas; Lechuga, Fernanda C.; Lucas, Elizabete F., E-mail: elucas@ima.ufrj.b [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Macromoleculas Profa. Eloisa Mano

    2010-07-01

    Water-in-crude oil emulsions are formed during petroleum production and asphaltenes play an important role in their stabilization. Demulsifiers are added to destabilize such emulsions,however the demulsification mechanism is not completely known. In this paper, the performances of commercial poly(ethylene oxide-b-propylene oxide) demulsifiers were studied using synthetic water-in-oil emulsions and model-systems (asphaltenes in organic solvent). No change in the asphaltene aggregate size induced by the demulsifier was observed. The demulsification performance decreased as the asphaltene aggregate size increased, so it can be suggested that the demulsification mechanism is correlated to the voids between the aggregates adsorbed on the water droplets surface. (author)

  19. Effect of the structure of commercial poly(ethylene oxide-b-propylene oxide demulsifier bases on the demulsification of water-in-crude oil emulsions: elucidation of the demulsification mechanism

    Directory of Open Access Journals (Sweden)

    João Batista V. S. Ramalho

    2010-01-01

    Full Text Available Water-in-crude oil emulsions are formed during petroleum production and asphaltenes play an important role in their stabilization. Demulsifiers are added to destabilize such emulsions,however the demulsification mechanism is not completely known. In this paper, the performances of commercial poly(ethylene oxide-b-propylene oxide demulsifiers were studied using synthetic water-in-oil emulsions and model-systems (asphaltenes in organic solvent. No change in the asphaltene aggregate size induced by the demulsifier was observed. The demulsification performance decreased as the asphaltene aggregate size increased, so it can be suggested that the demulsification mechanism is correlated to the voids between the aggregates adsorbed on the water droplets surface.

  20. In vitro antibacterial activity and major bioactive components of Cinnamomum verum essential oils against cariogenic bacteria, Streptococcus mutans and Streptococcus sobrinus

    Directory of Open Access Journals (Sweden)

    Okhee Choi

    2016-04-01

    Conclusions: The essential oil of C. verum and its major component cinnamaldehyde possessed considerable in vitro antibacterial activities against cariogenic bacteria, S. mutans and S. sobrinus strains. These results showed that the essential oil of C. verum and its bioactive component, cinnamaldehyde, have potential for application as natural agents for the prevention and treatment of dental caries.

  1. Investigation on used oil and engine components of vehicles road test using twenty percent Fatty Acid Methyl Ester (B20

    Directory of Open Access Journals (Sweden)

    Ihwan Haryono, Muhammad Ma’ruf, Hari Setiapraja

    2016-01-01

    Full Text Available The Indonesian government has mandated to utilize biodiesel at the Indonesian market with blend ratio of 20% biodiesel and 80% diesel fuel (B20. This policy bring car manufacturers concerning in using B20 effect on the engine life time. To evaluate the effect of using B20 on engine components, vehicles road test has been done along 40,000 KM. The test was using three brands of vehicles, in which each brand was composed of two identical vehicles fuelled by B20 FAME fuel and pure diesel fuel (B0 (solar. During the road test at certain intervals in accordance with the manufacturer's maintenance recommendations, the vehicles lubricating oil replacement and other routine maintenance were required. At the completion of the test all test vehicles to be dismantled and the engine components inspected. The test results show that the most parameter of used oil lubricants still in the limits. Likewise, the condition of the vehicles engine components did not show significant difference between using the pure diesel or B20.

  2. HINDERED DIFFUSION OF ASPHALTENES AT ELEVATED TEMPERATURE AND PRESSURE

    Energy Technology Data Exchange (ETDEWEB)

    James A. Guin; Zachery Emerson

    2001-10-01

    During this final time period of the project, work was carried out in two areas. A major amount of effort was devoted to preparation of the final technical report for the project. The data taken on the project were organized and the asphaltenes, solvents, and catalysts used in the diffusional uptake experiments were organized into various systems. Since a large portion of the time for this report was spent on the preparation of the final technical report itself, the executive summary of the final technical report has been included in this semi-annual report as indicative of the effort during this time period. In addition to work on the final technical report for the project, a limited experimental study of dye adsorption into active carbon particles was performed by an undergraduate student in chemical engineering, Mr. Zachery Emerson. The objective of this study was to compare the diffusional uptake performance in two different types of vessels, a stirred glass cell and the tubing microreactor, for a simple dye-water-carbon diffusional uptake system. Due to time limitations, only qualitative conclusions were drawn from this study.

  3. Kinetic modeling of multi‐component crystallization of industrial‐grade oils and fats

    DEFF Research Database (Denmark)

    Hjorth, Jeppe L.; Miller, Rasmus L.; Woodley, John M.;

    2015-01-01

    Transient crystallization kinetics is investigated for complex, industrial‐grade vegetable oils consisting of more than ten triacylglycerols (TAG). The classical nucleation model has been used to describe primary nucleation, while secondary nucleation has been described by a semi‐empirical approach...... describe how higher cooling rates lead to formation of more meta‐stable crystals and smaller mean‐crystal sizes. : The model provides a good starting point for developing more realistic, transient models for TAG crystallization with the ability to accommodate processing conditions and complex chemical......‐fat content (SFC) measurements for a given oil at different cooling rates and degrees of dilution. The developed model can accommodate more polymorphs simultaneously and performs well with respect to predicting crystallization onset, rate of crystallization and final SFC value. It can also qualitatively...

  4. Changes in the Essential Oil Components during the Development of Fennel Plants from Somatic Embryoids.

    Science.gov (United States)

    Miura, Y; Ogawa, K; Fukui, H; Tabata, M

    1987-02-01

    Quantitative and qualitative changes of essential oils during the development of clonal plants of fennel propagated through somatic embryogenesis were investigated. Although no essential oil could be detected either in cultured cells or in somatic embryoids, monoter-penes such as alpha-phellandrene and alpha-pinene were found in radical leaves of regenerated plantlets cultured on a hormone-free agar medium. The regenerated plants cultivated in the field for about one month accumulated phenylpropanoids such as estragole, anethole, and fenchone in addition to the two monoterpenes described above in radical leaves. Rich accumulations of phenylpropanoids and monoterpenes were observed in the fruits; especially the contents of estragole and anethole were much higher than in radical leaves.

  5. Evaluation of reservoir wettability and its effect on oil recovery. Annual report, February 1, 1996--January 31, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, J.S.

    1998-03-01

    We report on the first year of the project, {open_quotes}Evaluation of Reservoir Wettability and its Effect on Oil Recovery.{close_quotes} The objectives of this five-year project are: (1) to achieve improved understanding of the surface and interfacial properties of crude oils and their interactions with mineral surfaces, (2) to apply the results of surface studies to improve predictions of oil production from laboratory measurements, and (3) to use the results of this research to recommend ways to improve oil recovery by waterflooding. During the first year of this project we have focused on understanding the interactions between crude oils and mineral surfaces that establish wetting in porous media. Mixed-wetting can occur in oil reservoirs as a consequence of the initial fluid distribution. Water existing as thick films on flat surfaces and as wedges in comers can prevent contact of oil and mineral. Water-wet pathways are thus preserved. Depending on the balance of surface forces-which depend on oil, solid, and brine compositions-thick water films can be either stable or unstable. Water film stability has important implications for subsequent alteration of wetting in a reservoir. On surfaces exposed to oil, the components that are likely to adsorb and alter wetting can divided into two main groups: those containing polar heteroatoms, especially organic acids and bases; and the asphaltenes, large molecules that aggregate in solution and precipitate upon addition of n-pentane and similar agents. In order to understand how crude oils interact with mineral surfaces, we must first gather information about both these classes of compounds in a crude oil. Test procedures used to assess the extent of wetting alteration include adhesion and adsorption on smooth surfaces and spontaneous imbibition into porous media. Part 1 of this project is devoted to determining the mechanisms by which crude oils alter wetting.

  6. Insecticidal Activity of Essential Oil of Carum Carvi Fruits from China and Its Main Components against Two Grain Storage Insects

    Directory of Open Access Journals (Sweden)

    Shu Shan Du

    2010-12-01

    Full Text Available During our screening program for agrochemicals from Chinese medicinal herbs and wild plants, the essential oil of Carum carvi fruits was found to possess strong contact toxicity against Sitophilus zeamais and Tribolium castaneum adults, with LD50 values of 3.07 and 3.29 mg/adult, respectively, and also showed strong fumigant toxicity against the two grain storage insects with LC50 values of 3.37 and 2.53 mg/L, respectively. The essential oil obtained by hydrodistillation was investigated by GC and GC-MS. The main components of the essential oil were identified to be (R-carvone (37.98% and D-limonene (26.55% followed by α-pinene (5.21, cis-carveol (5.01% and b-myrcene (4.67%. (R-Carvone and D-limonene were separated and purified by silica gel column chromatography and preparative thin layer chromatography, and further identified by means of physicochemical and spectrometric analysis. (R-Carvone and D-limonene showed strong contact toxicity against S. zeamais (LD50 = 2.79 and 29.86 mg/adult and T. castaneum (LD50 = 2.64 and 20.14 mg/adult. (R-Carvone and D-limonene also possessed strong fumigant toxicity against S. zeamais (LC50 = 2.76 and 48.18 mg/L and T. castaneum adults (LC50 = 1.96 and 19.10 mg/L.

  7. Asphaltene Erosion Process in Air Plasma: Emission Spectroscopy and Surface Analysis for Air-Plasma Reactions

    Institute of Scientific and Technical Information of China (English)

    H. MARTINEZ; O. FLORES; J. C. POVEDA; B. CAMPILLO

    2012-01-01

    Optical emission spectroscopy (OES) was applied for plasma characterization during the erosion of asphaltene substrates. An amount of 100 mg of asphaltene was carefully applied to an electrode and exposed to air-plasma glow discharge at a pressure of 1.0 Torr. The plasma was generated in a stainless steel discharge chamber by an ac generator at a frequency of 60 Hz, output power of 50 W and a gas flow rate of 1.8 L/min. The electron temperature and ion density were estimated to be 2.15±0.11 eV and (1.24±0.05)× 10^16 m^-3, respectively, using a double Langmuir probe. OES was employed to observe the emission from the asphaltene exposed to air plasma. Both molecular band emission from N2, N2+, OH, CH, NH, O2 as well as CN, and atomic light emission from V and Hγ were observed and used to monitor the evolution of asphaltene erosion. The asphaltene erosion was analyzed with the aid of a scanning electron microscope (SEM) equipped with an energy dispersive X-ray (EDX) detector. The EDX analysis showed that the time evolution of elements C, O, S and V were similar and the chemical composition of the exposed asphaltenes remained constant. Particle size evolution was measured, showing a maximum size of 2307 μm after 60 min. This behavior is most likely related to particle agglomeration as a function of time.

  8. A study of some asphaltenes solutions structure and of a Safaniya vacuum residue

    Energy Technology Data Exchange (ETDEWEB)

    Guille, V.

    1996-05-20

    A lot of problems in the petroleum industry are due to the presence of asphaltenes compounds in petroleum products. A good knowledge of the chemical composition and the different properties of asphaltenes in solution are necessary to cope with these difficulties. We have then examined a Safaniya Vacuum Residue (VR) and its fractions (asphaltenes, resins, aromatics and saturates). In order to describe the macro-structure of these complex colloidal systems, we used different characterisation techniques: small angle X-ray and neutron scattering (SAXS and SANS), rheology and electron microscopy. Scattering techniques allows us to precise the model for asphaltenes and resins in solution. These macromolecules are poly-dispersed disk-like particles with thickness and diameter which are respectively close to 1 to 10 nm. The average molecular weight is equal to 106 000 for asphaltenes and 3 300 for resins. We have shown that SAXS is more sensitive to the scattering of the aromatic part of the molecule. Adding n-heptane induces first a de-solvation of the molecules and then an aggregation up to flocculation. These solutions present large heterogeneities due to concentration fluctuations. A huge difference in the chemical composition of the different asphaltenes molecules can explain these fluctuations. These heterogeneities are stable as a function of temperature; this means that exist strong molecular interactions. Ultracentrifugation gives two different fractions which contain different chemical structures, more or less aromatic. Solutions, in good solvent, of these two fractions are homogeneous but a mixture of these two fractions exhibits, heterogeneities. SAXS gives information about the structure of VR. We have observed the presence of large density fluctuations up to 300 deg. C. Rheological measurements confirm three-dimensional organisation. (author). 11 refs., 11 figs., 49 tabs.

  9. EPR and Fluorescence Spectroscopy in the Photodegradation Study of Arabian and Colombian Crude Oils

    Directory of Open Access Journals (Sweden)

    Carmen L. B. Guedes

    2006-01-01

    W/m2. The reduction in the linewidth of the free radical of 9.8% in Arabian oil and 18.5% in Colombian oil, as well as the decrease in radical numbers, indicated photochemical degradation, especially in Colombian oil. The linewidth narrowing corresponding to free radicals in the irradiated oils occurred due to the rearrangement among radicals and aromatic carbon consumption. The irradiated oils showed a reduction in the relative intensity of fluorescence of the aromatics with high molecular mass, polar aromatics, and asphaltene. The fluorescent fraction was reduced by 61% in Arabian oil and 72% in Colombian oil, corresponding to photochemical degradation of crude oil aromatic compounds.

  10. Ionic Liquids: Novel Solvents for Petroleum Asphaltenes%离子液体:石油沥青质的新型溶剂

    Institute of Scientific and Technical Information of China (English)

    刘艳升; 胡玉峰; 王海波; 徐春明; 纪德军; 孙研; 郭天民

    2005-01-01

    The dissolution of petroleum asphaltenes with ionic liquids is studied for the first time. The results show that the ionic liquids could be used as novel solvents for asphaltenes. The important parameters governing the ability of ionic liquids for dissolution of asphaltenes are discussed. It is found that, the ionic liquids based on the cations containing a conjugated aromatic core or the anions which are strong hydrogen bond acceptors are most for asphaltenes. Increase in the effective anion charge density enhances the ability of ionic liquids to break the extensive asphaltene associations and thus enhances the solubility of asphaltenes in the ionic liquid. The dissolution ability of ionic liquid decreases apparently with increasing the substituted alkyl chain length of its cationic head ring. Temperature is found to play an important role on dissolution of asphaltenes, and the dissolution can be significantly improved by microwave heating.

  11. Independent components analysis coupled with 3D-front-face fluorescence spectroscopy to study the interaction between plastic food packaging and olive oil.

    Science.gov (United States)

    Kassouf, Amine; El Rakwe, Maria; Chebib, Hanna; Ducruet, Violette; Rutledge, Douglas N; Maalouly, Jacqueline

    2014-08-11

    Olive oil is one of the most valued sources of fats in the Mediterranean diet. Its storage was generally done using glass or metallic packaging materials. Nowadays, plastic packaging has gained worldwide spread for the storage of olive oil. However, plastics are not inert and interaction phenomena may occur between packaging materials and olive oil. In this study, extra virgin olive oil samples were submitted to accelerated interaction conditions, in contact with polypropylene (PP) and polylactide (PLA) plastic packaging materials. 3D-front-face fluorescence spectroscopy, being a simple, fast and non destructive analytical technique, was used to study this interaction. Independent components analysis (ICA) was used to analyze raw 3D-front-face fluorescence spectra of olive oil. ICA was able to highlight a probable effect of a migration of substances with antioxidant activity. The signals extracted by ICA corresponded to natural olive oil fluorophores (tocopherols and polyphenols) as well as newly formed ones which were tentatively identified as fluorescent oxidation products. Based on the extracted fluorescent signals, olive oil in contact with plastics had slower aging rates in comparison with reference oils. Peroxide and free acidity values validated the results obtained by ICA, related to olive oil oxidation rates. Sorbed olive oil in plastic was also quantified given that this sorption could induce a swelling of the polymer thus promoting migration.

  12. Assessment of antioxidative, chelating, and DNA-protective effects of selected essential oil components (eugenol, carvacrol, thymol, borneol, eucalyptol) of plants and intact Rosmarinus officinalis oil.

    Science.gov (United States)

    Horvathova, Eva; Navarova, Jana; Galova, Eliska; Sevcovicova, Andrea; Chodakova, Lenka; Snahnicanova, Zuzana; Melusova, Martina; Kozics, Katarina; Slamenova, Darina

    2014-07-16

    Selected components of plant essential oils and intact Rosmarinus officinalis oil (RO) were investigated for their antioxidant, iron-chelating, and DNA-protective effects. Antioxidant activities were assessed using four different techniques. DNA-protective effects on human hepatoma HepG2 cells and plasmid DNA were evaluated with the help of the comet assay and the DNA topology test, respectively. It was observed that whereas eugenol, carvacrol, and thymol showed high antioxidative effectiveness in all assays used, RO manifested only antiradical effect and borneol and eucalyptol did not express antioxidant activity at all. DNA-protective ability against hydrogen peroxide (H2O2)-induced DNA lesions was manifested by two antioxidants (carvacrol and thymol) and two compounds that do not show antioxidant effects (RO and borneol). Borneol was able to preserve not only DNA of HepG2 cells but also plasmid DNA against Fe(2+)-induced damage. This paper evaluates the results in the light of experiences of other scientists.

  13. Aquathermolysis of conventional heavy oil with superheated steam

    Institute of Scientific and Technical Information of China (English)

    Song Guangshou; Zhou Tiyao; Cheng Linsong; Wang Yunxian; Tian Guoqing; Pi Jian; Zhang Zheng

    2009-01-01

    This paper presents a new aquathermolysis study of conventional heavy oil in superheated steam. A new high temperature autoclave was designed, where volume and pressure could be adjusted. Aquathermolysis was studied on two different conventional heavy oil samples under different reaction times and temperatures. Experimental results show that aquathermolysis does take place for conventional heavy oil. As reaction time increases, the oil viscosity reduces. However, the reaction will reach equilibrium after a certain period of time and won't be sensitive to any further reaction time any more. Analysis shows that, while resin and asphaltenes decrease, saturated hydrocarbons and the H/C ratio increase after reaction. The main mechanism of aquathermolysis includes hydrogenization, desulfuration reaction of resin and asphaltenes, etc.

  14. DEVELOPMENT OF MULTI-PHASE AND MULTI-COMPONENT FLOW MODEL WITH REACTION IN POROUS MEDIA FOR RISK ASSESSMENT ON SOIL CONTAMINATION DUE TO MINERAL OIL

    Science.gov (United States)

    Sakamoto, Yasuhide; Nishiwaki, Junko; Hara, Junko; Kawabe, Yoshishige; Sugai, Yuichi; Komai, Takeshi

    In late years, soil contamination due to mineral oil in vacant lots of oil factory and oil field has become obvious. Measure for soil contamina tion and risk assessment are neces sary for sustainable development of industrial activity. Especially, in addition to contaminated sites, various exposure paths for human body such as well water, soil and farm crop are supposed. So it is very important to comprehend the transport phenomena of contaminated material under the environments of soil and ground water. In this study, mineral oil as c ontaminated material consisting of mu lti-component such as aliphatic and aromatic series was modeled. Then numerical mode l for transport phenomena in surface soil and aquifer was constructed. On the basis of modeling for mineral oil, our numerical model consists of three-phase (oil, water and gas) forty three-component. This numerical model becomes base program for risk assessment system on soil contamination due to mineral oil. Using this numerical model, we carried out some numerical simulation for a laboratory-scale experiment on oil-water multi-phase flow. Relative permeability that dominate flow behavior in multi-phase condition was formulated and the validity of the numerical model developed in this study was considered.

  15. [Study on high accuracy detection of multi-component gas in oil-immerse power transformer].

    Science.gov (United States)

    Fan, Jie; Chen, Xiao; Huang, Qi-Feng; Zhou, Yu; Chen, Gang

    2013-12-01

    In order to solve the problem of low accuracy and mutual interference in multi-component gas detection, a kind of multi-component gas detection network with high accuracy was designed. A semiconductor laser with narrow bandwidth was utilized as light source and a novel long-path gas cell was also used in this system. By taking the single sine signal to modulate the spectrum of laser and using space division multiplexing (SDM) and time division multiplexing (TDM) technique, the detection of multi-component gas was achieved. The experiments indicate that the linearity relevance coefficient is 0. 99 and the measurement relative error is less than 4%. The system dynamic response time is less than 15 s, by filling a volume of multi-component gas into the gas cell gradually. The system has advantages of high accuracy and quick response, which can be used in the fault gas on-line monitoring for power transformers in real time.

  16. Comparative study on the radioactivity of TE-NORM in different components of oil separator tanks

    Energy Technology Data Exchange (ETDEWEB)

    Attallah, M.F.; Awwad, N.S.; Aly, H.F. [Atomic Energy Authority, Cairo (Egypt). Hot Laboratories and Management Center (HLWMC); El Afifi, E.M. [Atomic Energy Authority, Cairo (Egypt). Hot Laboratories and Management Center (HLWMC); Sebha Univ. (Libyan Arab Jamahiriya). Faculty of Engineering and Technology

    2013-03-01

    Natural radioactivity in the crude oil, produced water, sludge and scale wastes from the petroleum industry on the Suez gulf (Abu Redeis), Egypt were investigated. A low radioactivity was found in the produced water and crude oil samples. In the sludge waste samples, the levels of radioactivity were found to be 11.96 and 1.75 kBq kg{sup -1} for Ra-226 (of U-series) and Ra-228 (of Th-series), respectively. In the scale waste samples, the levels of radioactivity were 11.7 and 4.2 kBq kg{sup -1} for Ra-226 and Ra-228, respectively. Leaching of different radionuclides in the sludge and scale wastes was investigated using mineral acid alone or after treatment with certain carbonate solutions. The different parameters affecting the treatment were optimized. It is found that high removal of Ra-226 was achieved from sludge and scale wastes when pretreated with 10% sodium carbonate solution, followed by acid dissolution. Removal % of Ra-226 reached 77 and 87% from the sludge and scale wastes, respectively. (orig.)

  17. Wax deposition in crude oil pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Assuncao, Pablo Morelato; Rodrigues, Lorennzo Marrochi Nolding [Universidade Federal do Espirito Santo, Sao Mateus, ES (Brazil). Centro Universitario Norte do Espirito Santo. Engenharia de Petroleo; Romero, Mao Ilich [University of Wyoming, Laramie, WY (United States). Enhanced Oil Recovery Institute], e-mail: mromerov@uwyo.edu

    2010-07-01

    Crude oil is a complex mixture of hydrocarbons which consists of aromatics, paraffins, naphthenics, resins asphaltenes, etc. When the temperature of crude oil is reduced, the heavy components, like paraffin, will precipitate and deposit on the pipe internal wall in the form of a wax-oil gel. The gel deposit consists of wax crystals that trap some amount of oil. As the temperature gets cooler, more wax will precipitate and the thickness of the wax gel will increase, causing gradual solidification of the crude and eventually the oil stop moving inside the offshore pipeline. Crude oil may not be able to be re-mobilized during re-startup. The effective diameter will be reduced with wax deposition, resulting in several problems, for example, higher pressure drop which means additional pumping energy costs, poor oil quality, use of chemical components like precipitation inhibitors or flowing facilitators, equipment failure, risk of leakage, clogging of the ducts and process equipment. Wax deposition problems can become so sever that the whole pipeline can be completely blocked. It would cost millions of dollars to remediate an offshore pipeline that is blocked by wax. Wax solubility decreases drastically with decreasing temperature. At low temperatures, as encountered in deep water production, is easy to wax precipitate. The highest temperature below which the paraffins begins to precipitate as wax crystals is defined as wax appearance temperature (WAT). Deposition process is a complex free surface problem involving thermodynamics, fluid dynamics, mass and heat transfer. In this work, a numerical analysis of wax deposition by molecular diffusion and shear dispersion mechanisms in crude oil pipeline is studied. Diffusion flux of wax toward the wall is estimated by Fick's law of diffusion, in similar way the shear dispersion; wax concentration gradient at the solid-liquid interface is obtained by the volume fraction conservation equation; and since the wax deposition

  18. Cytotoxicity Evaluation of Essential Oil and its Component from Zingiber officinale Roscoe.

    Science.gov (United States)

    Lee, Yongkyu

    2016-07-01

    Zingiber officinale Roscoe has been widely used as a folk medicine to treat various diseases, including cancer. This study aims to re-examine the therapeutic potential of co-administration of natural products and cancer chemotherapeutics. Candidate material for this project, α-zingiberene, was extracted from Zingiber officinale Roscoe, and α-zingiberene makes up 35.02 ± 0.30% of its total essential oil. α-Zingiberene showed low IC50 values, 60.6 ± 3.6, 46.2 ± 0.6, 172.0 ± 6.6, 80.3 ± 6.6 (μg/mL) in HeLa, SiHa, MCF-7 and HL-60 cells each. These values are a little bit higher than IC50 values of general essential oil in those cells. The treatment of α-zingiberene produced nucleosomal DNA fragmentation in SiHa cells, and the percentage of sub-diploid cells increased in a concentration-dependent manner in SiHa cells, hallmark features of apoptosis. Mitochondrial cytochrome c activation and an in vitro caspase-3 activity assay demonstrated that the activation of caspases accompanies the apoptotic effect of α-zingiberene, which mediates cell death. These results suggest that the apoptotic effect of α-zingiberene on SiHa cells may converge caspase-3 activation through the release of mitochondrial cytochrome c into cytoplasm. It is considered that anti-proliferative effect of α-zingiberene is a result of apoptotic effects, and α-zingiberene is worth furthermore study to develop it as cancer chemotherapeutics.

  19. Study on Chemical Components of Essential Oil in Leaf of Beta vulgaris by GC-MS%甜菜叶挥发油成分GC-MS分析

    Institute of Scientific and Technical Information of China (English)

    于颖颖; 孙薇; 张晓叶; 曹晨; 孙琦; 孔德新; 刘银燕

    2012-01-01

    The chemical components of the essential oil from leaves of Beta vulgaris were analyzed by GC-MS metod. The essential oil was extracted from leaves of Beta vulgaris by steam distillation, and the amount of the components from the essential oil were determined by normalization method. The chemical components separated were identified by GC-MS method. There were 24 components consisted which were over 76.07% of the total essential oil. The method is reliable, stable and reproducible, and it can be applied to the analysis of chemical components in the essential oil extracted from chinese traditional medicine.%用气相色谱-质谱法对甜菜叶的挥发油进行化学成分分析.采用水蒸气蒸馏法从甜菜叶中提取挥发油,用归一化法测定其百分含量,并用气相色谱-质谱法对化学成分进行鉴定.共鉴定了24种成分,占挥发油总量的76.07%.本方法稳定可靠,重现性好,适合用于中药挥发油的化学成分分析.

  20. Evaluation of alkyl esters from Camelina sativa oil as biodiesel and as blend components in ultra low-sulfur diesel fuel.

    Science.gov (United States)

    Moser, Bryan R; Vaughn, Steven F

    2010-01-01

    Methyl and ethyl esters were prepared from camelina [Camelina sativa (L.) Crantz] oil by homogenous base-catalyzed transesterification for evaluation as biodiesel fuels. Camelina oil contained high percentages of linolenic (32.6 wt.%), linoleic (19.6 wt.%), and oleic (18.6 wt.%) acids. Consequently, camelina oil methyl and ethyl esters (CSME and CSEE) exhibited poor oxidative stabilities and high iodine values versus methyl esters prepared from canola, palm, and soybean oils (CME, PME, and SME). Other fuel properties of CSME and CSEE were similar to CME, PME, and SME, such as low temperature operability, acid value, cetane number, kinematic viscosity, lubricity, sulfur and phosphorous contents, as well as surface tension. As blend components in ultra low-sulfur diesel fuel, CSME and CSEE were essentially indistinguishable from SME and soybean oil ethyl ester blends with regard to low temperature operability, kinematic viscosity, lubricity, and surface tension.

  1. Changes in oxidation indices and minor components of low free fatty acid and freshly extracted crude palm oils under two different storage conditions.

    Science.gov (United States)

    Tan, Choon-Hui; Ariffin, Abdul A; Ghazali, Hasanah M; Tan, Chin-Ping; Kuntom, Ainie; Choo, Adrian Cheng-Yong

    2017-06-01

    This article reports on the changes of oxidation indices and minor components of low free fatty acid (FFA) and freshly extracted crude palm oils after storage at ambient (28 ± 1 C) and 60 C for 77 days. The changes in peroxide value (PV), FFA, extinction coefficient at 233 and 269 nm (K233 and K269), bleachability index (DOBI), carotene and vitamin E contents were monitored. PV, FFA, K233 and K269 of both oil samples increased as storage progressed while the values of carotene and vitamin E contents decreased. At the end of storage period at 60 °C, the carotene content of low FFA crude palm oil was 4.24 ppm. The storage conditions used led to the loss of entire vitamin E fractions of both oil samples as well as a reduction in DOBI values except for freshly extracted crude palm oil stored at ambient temperature.

  2. Molecular characterization of organically bound sulphur in crude oils. A feasibility study for the application of Raney Ni desulphurization as a new method to characterize crude oils

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Rijpstra, W.I.C.; Leeuw, J.W. de; Lijmbach, G.W.M.

    1994-01-01

    Five crude oils with varying sulfur contents (0.1 – 4.7%) were characterized on a molecular level for organically-bound sulfur. Aromatic fractions were analyzed by GC-(MS) and asphaltene and polar fractions were analyzed by flash pyrolysis-GC-(MS). The polar fractions were also desulfurized with Ran

  3. Nickel boride: An improved desulphurizing agent for sulphur-rich geomacromolecules in polar and asphaltene fractions

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Schouten, S.; Pavlovic, D.; Leeuw, J.W. de

    1993-01-01

    Nickel boride, a novel desulphurizing agent, was investigated for the desulphurization of sulphur-rich geomacromolecules in polar and asphaltene fractions. It was found to be as effective as the conventional desulphurizing agent, Raney nickel, for sulphur-rich geomacromolecules in polar fractions, b

  4. Resins and asphaltenes: evolution as a function of organic-matter type and burial

    Energy Technology Data Exchange (ETDEWEB)

    Castex, H. (Institut Francais du Petrole, 92 - Rueil-Malmaison (France))

    Elemental analysis was used to investigate 151 resins and 175 asphaltenes extracted from rocks from several basins. It was shown that: resins have higher mean carbon and hydrogen values as well as a lower C/H ratio than asphaltenes. Resins thus have a more aliphatic and or more alicyclic structure. On the other hand, asphaltenes contain more sulfur, oxygen and nitrogen. Different types of organic matter are revealed by an H/C, O/C diagram. Their chemical evolution with burial is characterized by a decrease in hydrogen, oxygen and sulfur contents. Proton nuclear magnetic resonance (NMR) and infrared spectroscopy (IRS) were used to follow the structural evolution of resins and asphaltenes coming from different types of organic matter (algal, marine and terrestrial) buried at increasing depths. NMR can be used to compute several structural parameters such as Fsub(A) aromaticity and the degree of sigma substitution of the aromatic system. These data were completed by infrared spectroscopy. Variations in the intensity of bands: decrease of aliphatic C-H and of C = O fonctions; increase of aromatic C-H and C = C are related to both the type of organic matter and its catagenesis.

  5. Potential application of oxygen containing gases to enhance gravity drainage in heavy oil bearing reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, I. [Hungarian Academy of Sciences, Miscolc (Hungary). Lab. for Mining Chemistry; Bauer, K. [Hungarian Academy of Sciences, Miscolc (Hungary). Lab. for Mining Chemistry; Lakatos-Szabo, J. [Hungarian Academy of Sciences, Miscolc (Hungary). Lab. for Mining Chemistry

    1997-06-01

    In the frame of laboratory studies the effect of air/natural CO{sub 2} mixtures on chemical composition of crude oil and gas phase, the rheological and interfacial properties, the flow mechanism and the safety measures were analyzed. The tests were performed at reservoir conditions (200 bar and 109 C) using natural rock, oil and gas samples. The oxygen content of the gas phase and the gas/oil ratio varied within wide limits. Both crude and asphaltene-free oil were used to determine the consequences of the low temperature oxidation. On the basis of the experimental results it was found that the oxygen content of the cap gas had been completely consumed by the chemical reactions (oxidation, condensation and water formation) before the asphaltene content set in equilibrium. Nearly 9% excess asphaltene formation was observed in both the crude and the asphaltene-free oils. The substantial increase in asphaltene content and the presence of colloidal water results in a measurable change in rheological and interfacial properties. Despite these factors the flow and displacement mechanism is only slightly influenced if the reservoir is of fractured character. On the other hand the in-situ oxidation of this heavy crude oil improves the efficiency of bitumen production and the quality of product used mostly for road construction. As a final statement, it was concluded that replacing the CO{sub 2} with oxygen containing inert gas, the chemical reactions can be in-situ regulated without jeopardizing the recovery efficiency. Application of the artificial gas cap concept opens new perspectives in EOR technology of karstic and fractured reservoirs containing medium and heavy crude oils in those cases where CO{sub 2} or CH gas is not available. (orig./MSK)

  6. Molecular Dynamics Simulation of Spontaneous Imbibition in Nanopores and Recovery of Asphaltenic Crude Oils Using Surfactants for EOR Applications Simulations de dynamique moléculaire d’imbibition spontanée dans des nanopores et pour la récupération d’huiles brutes asphalténiques en utilisant des agents tensioactifs pour des applications d’EOR

    Directory of Open Access Journals (Sweden)

    Stukan M.R.

    2012-12-01

    Full Text Available We present Molecular Dynamics (MD simulations of the imbibition process in nanopores in case of two different mechanisms of the wettability modification. We compare the imbibition of an aqueous surfactant solution into an oil-wet pore driven by surfactant adsorption onto the oil-wet rock surface (coating mechanism and the imbibition of an aqueous surfactants solution driven by surfactants removing the contaminant molecules from the originally water-wet surface (cleaning mechanism. Our results show qualitative difference in the imbibition dynamics in these two cases and indicate that MD simulation is a useful tool to investigate details of the imbibition mechanisms at the pore scale with direct implications for Enhanced Oil Recovery (EOR operations. Nous presentons des simulations de Dynamique Moleculaire (DM du processus d’imbibition dans des nanopores dans le cas de deux mecanismes differents de modification de mouillabilite. Nous comparons l’imbibition d’une solution aqueuse d’agent tensioactif dans un pore mouille d’huile entrainee par une adsorption d’agent tensioactif sur la surface de roche mouillee d’huile (mecanisme de revetement et l’imbibition d’une solution aqueuse d’agent tensioactif entrainee par des agents tensioactifs eliminant les molecules contaminantes de la surface originellement mouillee d’eau (mecanisme de nettoyage. Nos resultats montrent une difference qualitative en matiere de dynamique d’imbibition dans ces deux cas et indiquent que la simulation de DM constitue un outil utile pour etudier les mecanismes d’imbibition a l’echelle des pores avec des implications directes pour des operations de recuperation renforcee d’huile (EOR, Enhanced Oil Recovery.

  7. Inhibitory effects of various essential oils and individual components against extended-spectrum beta-lactamase (ESBL) produced by Klebsiella pneumoniae and their chemical compositions.

    Science.gov (United States)

    Orhan, Ilkay Erdogan; Ozcelik, Berrin; Kan, Yüksel; Kartal, Murat

    2011-10-01

    In the current study, in vitro inhibitory activity of several essential oils obtained from the cultivated plants, Foeniculum vulgare, Mentha piperita and M. spicata, Ocimum basilicum, Origanum majorana, O. onites, O. vulgare, Satureja cuneifolia, and a number of individual essential oil components of terpene and aromatic types were screened against 10 isolated strains of Klebsiella pneumoniae producing extended-spectrum beta-lactamase (ESBL) enzyme, which makes this microorganism quite resistant against the antibiotics: trimetoprime-sulfametoksazol, sulbactam-ampicilin, clavulonate-amoxicilin, ceftriaxon, cefepime, imipenem, ceftazidime, tobramicine, gentamisine, ofloxacin, and ciprofloksasin. All of the essential oils and the components exerted a remarkable inhibition ranging between 32 and 64 μg/mL against all of these strains as strong as the references (ampicilin and oflaxocin) inhibiting at 32 μg/mL. Besides, chemical compositions of the essential oils were elucidated by gas chromatography-mass spectrometry (GC-MS). The essential oils and the pure components widely found in essential oils screened herein have shown remarkable inhibition against ESBL-producing K. pneumoniae strains, which leads to the suggestion that they may be used as food preservatives for this purpose. Practical Application:  The essential oils obtained from Foeniculum vulgare, Mentha piperita and M. spicata, O.cimum basilicum, Origanum majorana, O. onites, O. vulgare, and Satureja cuneifolia as well as common essential oil components have shown notable inhibitory effects against 10 isolated strains of Klebsiella pneumoniae producing extended-spectrum beta-lactamase (ESBL) enzyme and they might be used as food preservative or ingredient. © 2011 Institute of Food Technologists®

  8. Potential of Plant Essential Oils and Their Components in Animal Agriculture – in vitro Studies on Antibacterial Mode of Action

    OpenAIRE

    Corliss A. O'bryan; Pendleton, Sean J.; Crandall, Philip G.; Ricke, Steven C.

    2015-01-01

    The broad field of agriculture is currently undergoing major changes in practices, with new catch phrases including organic and sustainable. Consumers are more aware than ever before of the food that they eat and they want food free of toxic chemicals, antibiotics and the like. The antimicrobial activity of essential oils and their components has been recognized for several years. Recent research has demonstrated that many of these essential oils have beneficial effects for livestock, includi...

  9. Determination of calcium, magnesium and zinc in lubricating oils by flame atomic absorption spectrometry using a three-component solution.

    Science.gov (United States)

    Zmozinski, Ariane V; de Jesus, Alexandre; Vale, Maria G R; Silva, Márcia M

    2010-12-15

    Lubricating oils are used to decrease wear and friction of movable parts of engines and turbines, being in that way essential for the performance and the increase of that equipment lifespan. The presence of some metals shows the addition of specific additives such as detergents, dispersals and antioxidants that improve the performance of these lubricants. In this work, a method for determination of calcium, magnesium and zinc in lubricating oil by flame atomic absorption spectrometry (F AAS) was developed. The samples were diluted with a small quantity of aviation kerosene (AVK), n-propanol and water to form a three-component solution before its introduction in the F AAS. Aqueous inorganic standards diluted in the same way have been used for calibration. To assess the accuracy of the new method, it was compared with ABNT NBR 14066 standard method, which consists in diluting the sample with AVK and in quantification by F AAS. Two other validating methods have also been used: the acid digestion and the certified reference material NIST (SRM 1084a). The proposed method provides the following advantages in relation to the standard method: significant reduction of the use of AVK, higher stability of the analytes in the medium and application of aqueous inorganic standards for calibration. The limits of detection for calcium, magnesium and zinc were 1.3 μg g(-1), 0.052 μg g(-1) and 0.41 μg g(-1), respectively. Concentrations of calcium, magnesium and zinc in six different samples obtained by the developed method did not differ significantly from the results obtained by the reference methods at the 95% confidence level (Student's t-test and ANOVA). Therefore, the proposed method becomes an efficient alternative for determination of metals in lubricating oil.

  10. Antibacterial Effects and Mode of Action of Selected Essential Oils Components against Escherichia coli and Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Julio Cesar Lopez-Romero

    2015-01-01

    Full Text Available Bacterial resistance has been increasingly reported worldwide and is one of the major causes of failure in the treatment of infectious diseases. Natural-based products, including plant secondary metabolites (phytochemicals, may be used to surpass or reduce this problem. The objective of this study was to determine the antibacterial effect and mode of action of selected essential oils (EOs components: carveol, carvone, citronellol, and citronellal, against Escherichia coli and Staphylococcus aureus. The minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC were assessed for the selected EOs components. Moreover, physicochemical bacterial surface characterization, bacterial surface charge, membrane integrity, and K+ leakage assays were carried out to investigate the antimicrobial mode of action of EOs components. Citronellol was the most effective molecule against both pathogens, followed by citronellal, carveol, and carvone. Changes in the hydrophobicity, surface charge, and membrane integrity with the subsequent K+ leakage from E. coli and S. aureus were observed after exposure to EOs. This study demonstrates that the selected EOs have significant antimicrobial activity against the bacteria tested, acting on the cell surface and causing the disruption of the bacterial membrane. Moreover, these molecules are interesting alternatives to conventional antimicrobials for the control of microbial infections.

  11. p-Anisaldehyde: acaricidal component of Pimpinella anisum seed oil against the house dust mites Dermatophagoides farinae and Dermatophagoides pteronyssinus.

    Science.gov (United States)

    Lee, Hoi-Seon

    2004-03-01

    The acaricidal activity of anise seed oil-derived p-anisaldehyde and commercially available components of anise seed oil was examined against Dermatophagoides farinae and D. pteronyssinus and compared with those of the synthetic acaricides, benzyl benzoate and N,N-diethyl- m-toluamide (DEET). On the basis of LD 50 values, the compound most toxic to D. farinae adults was p-anisaldehyde (1.11 microg/cm2) followed by benzyl benzoate (9.32 microg/cm2), DEET (36.84 microg/cm2), 3-carene (42.10 microg/cm2), and estragol (43.23 microg/cm2). Against D. pteronyssinus adults, p-anisaldehyde (0.98 microg/cm2) was much more effective than benzyl benzoate (6.54 microg/cm2), DEET (17.79 microg/cm2), 3-carene (39.84 microg/cm 2), and estragol (40.11 microg/cm2). p-Anisaldehyde was about 8.4 and 6.7 times more toxic than benzyl benzoate against D. farinae and D. pteronyssinus adults, respectively. The results suggested that p-anisaldehyde may be useful as a lead compound for the development of new agents for the selective control of house dust mites.

  12. NEMS International Energy Module, model documentation report: World Oil Market, Petroleum Products Supply and Oxygenates Supply components

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-04

    The Energy Information Administration (EIA) is developing the National Energy Modeling System (NEMS) to enhance its energy forecasting capabilities and to provide the Department of Energy with a comprehensive framework for analyzing alternative energy` futures. NEMS is designed with a multi-level modular structure that represents specific energy supply activities, conversion processes, and demand sectors as a series of self-contained units which are linked by an integrating mechanism. The NEMS International Energy Module (IEM) computes world oil prices and the resulting patterns of international trade in crude oil and refined products. This report is a reference document for energy analysts, model users, and the public that is intended to meet EIA`s legal obligation to provide adequate documentation for all statistical and forecast reports (Public Law 93-275, section 57(b)(1). Its purpose is to describe the structure of the IEM. Actual operation of the model is not discussed here. The report contains four sections summarizing the overall structure of the IEM and its interface with other NEMS modules, mathematical specifications of behavioral relationships, and data sources and estimation methods. Following a general description of the function and rationale of its key components, system and equation level information sufficient to permit independent evaluation of the model`s technical details is presented.

  13. GC/GC-MS analysis, isolation and identification of bioactive essential oil components from the Bhutanese medicinal plant, Pleurospermum amabile.

    Science.gov (United States)

    Wangchuk, Phurpa; Keller, Paul A; Pyne, Stephen G; Taweechotipatr, Malai; Kamchonwongpaisan, Sumalee

    2013-09-01

    We have hydrodistilled the essential oil (EO) from the aerial parts of the Bhutanese medicinal plant, Pleurospermum amabile using a Clevenger apparatus and evaluated this EO by GC/GC-MS and NMR analysis followed by testing for bioactivity. The GC-MS analysis identified 52 compounds with (E)-isomyristicin as a major component (32.2%). Repeated purification yielded four compounds; (E)-isomyristicin (1), (E)-isoapiol (2), methyl eugenol (3) and (E)-isoelemicin (4). Compound 2 and the mother EO showed the best antiplasmodial activity against the Plasmodium falciparum strains, TM4/8.2 (chloroquine and antifolate sensitive) and K1CB1 (multidrug resistant). They exhibited mild antibacterial activity against Bacillus subtilis. None of the test samples showed cytotoxicity.

  14. Water-Soluble Components of Sesame Oil Reduce Inflammation and Atherosclerosis.

    Science.gov (United States)

    Narasimhulu, Chandrakala Aluganti; Selvarajan, Krithika; Burge, Kathryn Young; Litvinov, Dmitry; Sengupta, Bhaswati; Parthasarathy, Sampath

    2016-07-01

    Atherosclerosis, a major form of cardiovascular disease, is now recognized as a chronic inflammatory disease. Nonpharmacological means of treating chronic diseases have gained attention recently. We previously reported that sesame oil aqueous extract (SOAE) has anti-inflammatory properties, both in vitro and in vivo. In this study, we have investigated the antiatherosclerotic properties of SOAE, and the mechanisms, through genes and inflammatory markers, by which SOAE might modulate atherosclerosis. Low-density lipoprotein receptor (LDL-R) knockout female mice were fed with either a high-fat (HF) diet or an HF diet supplemented with SOAE. Plasma lipids and atherosclerotic lesions were quantified after 3 months of feeding. Plasma samples were used for global cytokine array. RNA was extracted from both liver tissue and the aorta, and used for gene analysis. The high-fat diet supplemented with SOAE significantly reduced atherosclerotic lesions, plasma cholesterol, and LDL cholesterol levels in LDL-R(-/-) mice. Plasma inflammatory cytokines were reduced in the SOAE diet-fed animals, but not significantly, demonstrating potential anti-inflammatory properties of SOAE. Gene analysis showed the HF diet supplemented with SOAE reduced gene expression involved in inflammation and induced genes involved in cholesterol metabolism and reverse cholesterol transport, an anti-inflammatory process. Our studies suggest that a SOAE-enriched diet could be an effective nonpharmacological treatment for atherosclerosis by controlling inflammation and regulating lipid metabolism.

  15. Compound-specific isotope analysis as a tool for characterizing mixed oils: an example from the West of Shetlands area

    Energy Technology Data Exchange (ETDEWEB)

    Rooney, M.A.; Vuletich, A.K. [Mobil Technology Co., Dallas, TX (United States); Griffith, C.E. [Mobil North Sea Ltd., London (United Kingdom)

    1998-12-31

    The origin of an oil accumulation can be difficult to establish when the oil is a mixture from multiple sources, or when multiple episodes of charging are involved. In this study, oils from the Clair field, West of Shetland Islands, which are mixtures of nonbiodegraded oil added to biodegraded oil, are characterized by comparing the carbon isotope ratios of the gasoline-range hydrocarbons (GRH) of the oil to the GRH released from the pyrolysis of the asphaltenes in the oil. The comparison allows characterization of the source of the first versus the second pulse of oil into the reservoir, information useful in assessing the source potential of the basin. (author)

  16. Effects of pH on protein components of extracted oil bodies from diverse plant seeds and endogenous protease-induced oleosin hydrolysis.

    Science.gov (United States)

    Zhao, Luping; Chen, Yeming; Chen, Yajing; Kong, Xiangzhen; Hua, Yufei

    2016-06-01

    Plant seeds are used to extract oil bodies for diverse applications, but oil bodies extracted at different pH values exhibit different properties. Jicama, sunflower, peanut, castor bean, rapeseed, and sesame were selected to examine the effects of pH (6.5-11.0) on the protein components of oil bodies and the oleosin hydrolysis in pH 6.5-extracted oil bodies. In addition to oleosins, many extrinsic proteins (globulins, 2S albumin, and enzymes) were present in pH 6.5-extracted oil bodies. Globulins were mostly removed at pH 8.0, whereas 2S albumins were removed at pH 11.0. At pH 11.0, highly purified oil bodies were obtained from jicama, sunflower, peanut, and sesame, whereas lipase remained in the castor bean oil bodies and many enzymes in the rapeseed oil bodies. Endogenous protease-induced hydrolysis of oleosins occurred in all selected plant seeds. Oleosins with larger sizes were hydrolysed more quickly than oleosins with smaller sizes in each plant seed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. In vitro antibacterial activity and major bioactive components of Cinnamomum verum essential oils against cariogenic bacteria,Streptococcus mutans and Streptococcus sobrinus

    Institute of Scientific and Technical Information of China (English)

    Okhee Choi; Su Kyung Cho; Junheon Kim; Chung Gyoo Park; Jinwoo Kim

    2016-01-01

    Objective:To evaluate the antibacterial activity of Cinnamomum verum(C.verum) from32 different essential oils against cariogenic bacteria,Streptococcus mutans(S.mutans)and Streptococcus sobrinus(S.sobrinus).Methods:The antibacterial activities of each essential oil were individually investigated against S.mutans and S.sobrinus.The essential oil of C.verum was selected for further evaluation against S.mutans and S.sobrinus.Gas chromatography mass spectrometry was used to determine the major constituents of C.verum essential oil.In addition,the minimum inhibitory concentration(MIC) and minimum bactericidal concentration of the most effective constituent was investigated.Results:The essential oil from C.verum exhibited the greatest antibacterial activity.Gas chromatography mass spectrometry analysis revealed that the major components of C.verum essential oil were cinnamaldehyde(56.3%),cinnamyl acetate(7.1%) and bphellandrene(6.3%).The MIC of cinnamaldehyde was measured using broth dilution assays.The MIC of cinnamaldehyde was 0.02%(v/v) against both bacterial strains tested.The minimum bactericidal concentration of cinnamaldehyde against S.mutans and S.sobrinus were 0.2% and 0.1%(v/v),respectively.Conclusions:The essential oil of C.verum and its major component cinnamaldehyde possessed considerable in vitro antibacterial activities against cariogenic bacteria,S.mutans and S.sobrinus strains.These results showed that the essential oil of C.verum and its bioactive component,cinnamaldehyde,have potential for application as natural agents for the prevention and treatment of dental caries.

  18. The essential oil of Melaleuca alternifolia (tea tree oil) and its main component, terpinen-4-ol protect mice from experimental oral candidiasis.

    Science.gov (United States)

    Ninomiya, Kentaro; Maruyama, Naho; Inoue, Shigeharu; Ishibashi, Hiroko; Takizawa, Toshio; Oshima, Haruyuki; Abe, Shigeru

    2012-01-01

    The therapeutic efficacy of tea tree oil (TTO), Melaleuca alternifolia, and its main component, terpinen-4-ol, were evaluated in a murine oral candidiasis model. Prednisolone -pretreated mice were orally infected with a fluconazole-susceptible (TIMM 2640) or a resistant (TIMM 3163) strain of Candida albicans to induce oral candidiasis. TTO or terpinen-4-ol was administrated with a cotton swab 3 h and 24 h after candida infection. These treatments clearly showed a decrease in the symptom score of tongues and in the viable candida cell number in the oral cavity at 2 d after azole-susceptible C. albicans infection, although the degree of the efficacy was less than that of fluconazole. Even against oral candidiasis caused by azole-resistant C. albicans, TTO and terpinen-4-ol were similarly effective, while fluconazole appeared ineffective. These results suggest that TTO and terpinen-4-ol may have the potential of therapeutic ability for mucosal candidiasis which may also be applicable to C. albicans oral candidiasis induced by the azole-resistant strain.

  19. The influence of petroleum asphaltenic sub fractions on the demulsifiers performance; Influencia de subfracoes asfaltenicas de petroleo sobre a acao de desemulsificantes

    Energy Technology Data Exchange (ETDEWEB)

    Honse, Siller O.; Mansur, Claudia R.E.; Lucas, Elizabete F. [Universidade Federal do Rio de Janeiro (IMA/UFRJ), RJ (Brazil). Inst. de Macromoleculas. Lab. de Macromoleculas e Coloides na Industria de Petroleo], e-mail: celias@ima.ufrj.br

    2011-07-01

    The aim of this work is to evaluate the influence of asphaltene fractions and subfractions on the stabilization of petroleum emulsions, as well as on the efficiency of demulsifiers based on poly(ethylene oxide-b-propylene oxide) (PEO-PPO). Asphaltenes were extracted from an asphaltic residue using n-heptane (C5 asphaltenes) and n-decane (asphaltenes C10). Intermediate subfractions were also obtained. Model emulsions, consisted of water and dispersions of the asphaltene in toluene were prepared, with and without adding demulsifier. The stability of the emulsions was higher when adding more polar fractions. However, asphaltenes presenting a broad distribution of polarity cause higher emulsion stability than that presenting very narrow distribution of intermediate polarity. The efficiency of PEO-PPO copolymer on emulsions separation is related to the original stability of the emulsions. In this work, it was confirmed that branched surfactant presents higher efficiency than the linear. (author)

  20. Understanding heavy-oil molecular functionality and relations to fluid properties

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, S.I. [Schlumberger, DBR Technology Center, Edmonton AB (Canada)

    2011-07-01

    In the heavy oil industry, knowing oil properties is important to optimizing recovery, transport and refinery. Nitrogen, sulfur and oxygen compounds (NSOs) have an important impact on these properties but this is often overlooked. The purpose of this paper is to analyze the impact of functional groups in connection with heavy oil and asphaltenes. Experiments were carried out with asphaltenes altered by chemical surgery that removed specific functional interactions. Titration calorimetry and fluorescence spectroscopy were then done. Results highlighted the fact that functional groups are of key importance in the determination of heavy oil properties and that acidity can be considered the most important interaction. This paper demonstrated that the determination of specific interactions could be more important in assessing heavy oil properties than understanding their hydrocarbon structure; further work is needed to fully understand the role of sulfur and nitrogen species.

  1. Characterization of oil and gas reservoir heterogeneity. Annual report, November 1, 1990--October 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    The objective of the cooperative research program is to characterize Alaskan reservoirs in terms of their reserves, physical and chemical properties, geologic configuration and structure, and the development potential. The tasks completed during this period include: (1) geologic reservoir description of Endicott Field; (2) petrographic characterization of core samples taken from selected stratigraphic horizons of the West Sak and Ugnu (Brookian) wells; (3) development of a polydispersed thermodynamic model for predicting asphaltene equilibria and asphaltene precipitation from crude oil-solvent mixtures, and (4) preliminary geologic description of the Milne Point Unit.

  2. Rheological properties of crude oils in Yaregskoye and Yaraktinskoye oil fields

    Science.gov (United States)

    Manzhai, V. N.; Le Grand Monkam Monkam, Clovis; Terre, D. A.

    2016-09-01

    Rotary viscometer tests of crude oil with a high content of resins and asphaltenes (Yaregskoye oil field) and crude oil with high paraffin content (Yaraktinskoye oil field) have been conducted. The typical flow curves for these oil types have been plotted. It has been detected that these oils are non-Newtonian fluids, viscosity of which is dependent on shear rate. Based on Arrhenius-Eyring equation, calculations of viscous flow activation energy and complex structural unit (CSU) sizes have been performed. It has been stated that there is a tenfold reduction in CSU size in asphaltic crude oil with the increase in shear rate in a rotary viscometer, while particle size in paraffinic crude oil does not essentially change under the same hydrodynamic conditions.

  3. Toxic and hormetic-like effects of three components of citrus essential oils on adult Mediterranean fruit flies (Ceratitis capitata).

    Science.gov (United States)

    Papanastasiou, Stella A; Bali, Eleftheria-Maria D; Ioannou, Charalampos S; Papachristos, Dimitrios P; Zarpas, Kostas D; Papadopoulos, Nikos T

    2017-01-01

    Plant essential oils (EOs) and a wide range of their individual components are involved in a variety of biological interactions with insect pests including stimulatory, deterrent, toxic and even hormetic effects. Both the beneficial and toxic properties of citrus EOs on the Mediterranean fruit fly (medfly) have been experimentally evidenced over the last years. However, no information is available regarding the toxic or beneficial effects of the major components of citrus EOs via contact with the adults of the Mediterranean fruit fly. In the present study, we explored the toxicity of limonene, linalool and α-pinene (3 of the main compounds of citrus EOs) against adult medflies and identified the effects of sub-lethal doses of limonene on fitness traits in a relaxed [full diet (yeast and sugar)] and in a stressful (sugar only) feeding environment. Our results demonstrate that all three compounds inferred high toxicity to adult medflies regardless of the diet, with males being more sensitive than females. Sub-lethal doses of limonene (LD20) enhanced the lifespan of adult medflies when they were deprived of protein. Fecundity was positively affected when females were exposed to limonene sub-lethal doses. Therefore, limonene, a major constituent of citrus EOs, induces high mortality at increased doses and positive effects on life history traits of medfly adults through contact at low sub-lethal doses. A hormetic-like effect of limonene to adult medflies and its possible underlying mechanisms are discussed.

  4. Simulation of phase separation with large component ratio for oil-in-water emulsion in ultrasound field.

    Science.gov (United States)

    Wang, Heping; Li, Xiaoguang; Li, Yanggui; Geng, Xingguo

    2017-05-01

    This paper presents an exploration for separation of oil-in-water and coalescence of oil droplets in ultrasound field via lattice Boltzmann method. Simulations were conducted by the ultrasound traveling and standing waves to enhance oil separation and trap oil droplets. The focus was to the effect of ultrasound irradiation on oil-in-water emulsion properties in the standing wave field, such as oil drop radius, morphology and growth kinetics of phase separation. Ultrasound fields were applied to irradiate the oil-in-water emulsion for getting flocculation of the oil droplets in 420kHz case, and larger dispersed oil droplets and continuous phases in 2MHz and 10MHz cases, respectively. The separated phases started to rise along the direction of sound propagation after several periods. The rising rate of the flocks was significantly greater in ultrasound case than that of oil droplets in the original emulsion, indicating that ultrasound irradiation caused a rapid increase of oil droplet quantity in the progress of the separation. The separation degree was also significantly improved with increasing frequency or irradiation time. The dataset was rearranged for growth kinetics of ultrasonic phase separation in a plot by spherically averaged structure factor and the ratio of oil and emulsion phases. The analyses recovered the two different temporal regimes: the spinodal decomposition and domain growth stages, which further quantified the morphology results. These numerical results provide guidance for setting the optimum condition for the separation of oil-in-water emulsion in the ultrasound field.

  5. On the determination of molecular weight distributions of asphaltenes and their aggregates in laser desorption ionization experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hortal, A.R.; Martinez-Haya, B.; Lobato, M.D.; Pedrosa, J.M.; Lago, S. [University of Pablo Olavide, Seville (Spain)

    2006-07-15

    Molecular weight distributions (MWD) of asphaltenes and their aggregates have been investigated in laser desorption ionization (LDI) mass spectrometric experiments. A systematic investigation of the dependence of the measured MIND on the asphaltene sample density and on the laser pulse energy allows the assignment of most probable molecular weights within 300-500 amu and average molecular weights of 800-1000 amu for the monomeric asphaltenes, as well as for the estimation of the contribution from asphaltene clusters in typical LDI measurements. The results serve to reconcile the existing controversy between earlier mass spectrometric characterizations of asphaltenes based on laser desorption techniques by different groups. Furthermore, the MWD measurements performed on particularly dense samples yield an additional differentiated broad band peaking around 9000-10,000 amu and extending over 20,000 amu, not observed previously in LDI experiments, thereby revealing a strong propensity of the asphaltenes to form clusters with specific aggregation numbers, which is in qualitative agreement with previous theoretical predictions and with the interpretation of measurements performed with other techniques.

  6. In vitro activity of essential oils of Lippia sidoides and Lippia gracilis and their major chemical components against Thielaviopsis paradoxa, causal agent of stem bleeding in coconut palms

    Directory of Open Access Journals (Sweden)

    Rejane Rodrigues da Costa e Carvalho

    2013-01-01

    Full Text Available Essential oils of Lippia sidoides, Lippia gracilis and their main chemical components were investigated for in vitro control of Thielaviopsis paradoxa. Mycelial growth and a number of pathogen conidia were inhibited by the essential oil of L. sidoides at all concentrations tested (0.2; 0.5; 1.0; 3.0 µL mL-1. L. sidoides oil contained 42.33% thymol and 4.56% carvacrol, while L. gracilis oil contained 10% thymol and 41.7% carvacrol. Mycelial growth and conidial production of T. paradoxa were completely inhibited by thymol at a 0.3 µL m-1 concentration. The results suggest that thymol could potentially be used for controlling coconut stem bleeding.

  7. Antimicrobial activity of the bioactive components of essential oils from Pakistani spices against Salmonella and other multi-drug resistant bacteria

    Science.gov (United States)

    2013-01-01

    Background The main objective of this study was the phytochemical characterization of four indigenous essential oils obtained from spices and their antibacterial activities against the multidrug resistant clinical and soil isolates prevalent in Pakistan, and ATCC reference strains. Methods Chemical composition of essential oils from four Pakistani spices cumin (Cuminum cyminum), cinnamon (Cinnamomum verum), cardamom (Amomum subulatum) and clove (Syzygium aromaticum) were analyzed on GC/MS. Their antibacterial activities were investigated by minimum inhibitory concentration (MIC) and Thin-Layer Chromatography-Bioautographic (TLC-Bioautographic) assays against pathogenic strains Salmonella typhi (D1 Vi-positive), Salmonella typhi (G7 Vi-negative), Salmonella paratyphi A, Escherichia coli (SS1), Staphylococcus aureus, Pseudomonas fluorescens and Bacillus licheniformis (ATCC 14580). The data were statistically analyzed by using Analysis of Variance (ANOVA) and Least Significant Difference (LSD) method to find out significant relationship of essential oils biological activities at p essential oils, oil from the bark of C. verum showed best antibacterial activities against all selected bacterial strains in the MIC assay, especially with 2.9 mg/ml concentration against S. typhi G7 Vi-negative and P. fluorescens strains. TLC-bioautography confirmed the presence of biologically active anti-microbial components in all tested essential oils. P. fluorescens was found susceptible to C. verum essential oil while E. coli SS1 and S. aureus were resistant to C. verum and A. subulatum essential oils, respectively, as determined in bioautography assay. The GC/MS analysis revealed that essential oils of C. cyminum, C. verum, A. subulatum, and S. aromaticum contain 17.2% cuminaldehyde, 4.3% t-cinnamaldehyde, 5.2% eucalyptol and 0.73% eugenol, respectively. Conclusions Most of the essential oils included in this study possessed good antibacterial activities against selected multi

  8. Homogenity of oil and sugar components of flour amaranth investigated by GC-MS

    Directory of Open Access Journals (Sweden)

    Psodorov Đorđe B.

    2015-01-01

    Full Text Available Gas chromatography with mass spectrometry (GC-MS was used for performing a qualitative analysis of liposoluble and hydrosoluble flour extracts of three genotypes of Amaranthus sp. All three samples were first defatted with hexane. Hexane extracts were used for the analysis of fatty acids of lipid components. TMSH (Trimethylsulfonium hydroxide, 0.2M in methanol was used as the transesterification reagent. With transesterification reaction, fatty acids were esterified from acilglycerol to methyl-esters. Defatted flour samples were dried in the air and then extracted with ethanol. Ethanol extracts were used for the analysis of soluble carbohydrates. TMSI (trimethylsilylimidazole was used as a reagent for the derivatization of carbohydrates into trimethylsilylethers. The results show that the dominant methyl-esters of fatty acids are very similar in all the three samples. Such a similarity was not detected in the analysis of soluble sugars. The following test cluster analysis was used for the comparison of liposoluble and hydrosoluble flour extracts of three genotypes of Amaranthus sp.

  9. Additive Regulation of Adiponectin Expression by the Mediterranean Diet Olive Oil Components Oleic Acid and Hydroxytyrosol in Human Adipocytes

    Science.gov (United States)

    Scoditti, Egeria; Massaro, Marika; Carluccio, Maria Annunziata; Pellegrino, Mariangela; Wabitsch, Martin; Calabriso, Nadia; Storelli, Carlo; De Caterina, Raffaele

    2015-01-01

    Adiponectin, an adipocyte-derived insulin-sensitizing and anti-inflammatory hormone, is suppressed in obesity through mechanisms involving chronic inflammation and oxidative stress. Olive oil consumption is associated with beneficial cardiometabolic actions, with possible contributions from the antioxidant phenol hydroxytyrosol (HT) and the monounsaturated fatty acid oleic acid (OA, 18:1n-9 cis), both possessing anti-inflammatory and vasculo-protective properties. We determined the effects of HT and OA, alone and in combination, on adiponectin expression in human and murine adipocytes under pro-inflammatory conditions induced by the cytokine tumor necrosis factor(TNF)-α. We used human Simpson-Golabi-Behmel syndrome (SGBS) adipocytes and murine 3T3-L1 adipocytes as cell model systems, and pretreated them with 1-100 μmol/L OA, 0.1-20 μmol/L HT or OA plus HT combination before stimulation with 10 ng/mL TNF-α. OA or HT significantly (Padiponectin secretion (by 42% compared with TNF-α alone) as well as mRNA levels (by 30% compared with TNF-α alone). HT and OA also prevented—by 35%—TNF-α-induced downregulation of peroxisome proliferator-activated receptor PPARγ. Co-treatment with HT and OA restored adiponectin and PPARγ expression in an additive manner compared with single treatments. Exploring the activation of JNK, which is crucial for both adiponectin and PPARγ suppression by TNF-α, we found that HT and OA additively attenuated TNF-α-stimulated JNK phosphorylation (up to 55% inhibition). In conclusion, the virgin olive oil components OA and HT, at nutritionally relevant concentrations, have additive effects in preventing adiponectin downregulation in inflamed adipocytes through an attenuation of JNK-mediated PPARγ suppression. PMID:26030149

  10. Anti-inflammatory and antioxidant activities of the nonlipid (aqueous) components of sesame oil: potential use in atherosclerosis.

    Science.gov (United States)

    Selvarajan, Krithika; Narasimhulu, Chandrakala Aluganti; Bapputty, Reena; Parthasarathy, Sampath

    2015-04-01

    Dietary intervention to prevent inflammation and atherosclerosis has been a major focus in recent years. We previously reported that sesame oil (SO) was effective in inhibiting atherosclerosis in low-density lipoprotein-receptor negative mice. We also noted that the levels of many proinflammatory markers were lower in the SO-treated animals. In this study we tested whether the non-lipid, aqueous components associated with SO would have anti-inflammatory and antioxidant effects. Polymerase chain reaction array data indicated that sesame oil aqueous extract (SOAE) was effective in reducing lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophage cells. Expression of inflammatory cytokines such as interleukin (IL)-1α, IL-6, and tumor necrosis factor α (TNF-α) was also analyzed independently in cells pretreated with SOAE followed by inflammatory assault. Effect of SOAE on TNF-α-induced MCP-1 and VCAM1 expression was also tested in human umbilical vein endothelial cells. We observed that SOAE significantly reduced inflammatory markers in both macrophages and endothelial cells in a concentration-dependent manner. SOAE was also effective in inhibiting LPS-induced TNF-α and IL-6 levels in vivo at different concentrations. We also noted that in the presence of SOAE, transcription and translocation of NF-kappaB was suppressed. SOAE was also effective in inhibiting oxidation of lipoproteins in vitro. These results suggest the presence of potent anti-inflammatory and antioxidant compounds in SOAE. Furthermore, SOAE differentially regulated expression of scavenger receptors and increased ATP-binding cassette A1 (ABCA1) mRNA expression by activating liver X receptors (LXRs), suggesting additional effects on lipid metabolism. Thus, SOAE appears multipotent and may serve as a valuable nonpharmacological agent in atherosclerosis and other inflammatory diseases.

  11. Impact of Liquid-Vapor to Liquid-Liquid-Vapor Phase Transitions on Asphaltene-Rich Nanoaggregate Behavior in Athabasca Vacuum Residue + Pentane Mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Long, Bingwen; Chodakowski, Martin; Shaw, John M. [Alberta; (Beijing U)

    2013-06-05

    The bulk phase behavior of heavy oil + alkane mixtures and the behavior of the asphaltenes that they contain are topics of importance for the design and optimization of processes for petroleum production, transport, and refining and for performing routine saturates, aromatics, resins, and asphaltenes (SARA) analyses. In prior studies, partial phase diagrams and phase behavior models for Athabasca vacuum residue (AVR) comprising 32 wt % pentane asphaltenes + n-alkanes were reported. For mixtures with pentane, observed phase behaviors included single-phase liquid as well as liquid–liquid, liquid–liquid–vapor, and liquid–liquid–liquid–vapor regions. Dispersed solids were detected under some conditions as well but not quantified. In this work, small-angle X-ray scattering (SAXS) is used to study nanostructured materials in liquid phases present in AVR + n-pentane mixtures from 50 to 170 °C at mixture bubble pressure. The investigation focuses on the impact of the transition from a single AVR-rich liquid to co-existing pentane-rich and AVR-rich liquids on the nanostructure and the nanostructures most resistant to aggregation as the pentane composition axis is approached. Background scattering subtraction was performed using global mixture composition. The robustness of this assumption with respect to values obtained for coefficients appearing in a two level Beaucage unified equation fit is demonstrated. The nanostructured material is shown to arise at two length scales from 1 to 100 wt % AVR. Smaller nanostructures possess mean radii less than 50 Å, while the larger nanostructures possess mean radii greater than 250 Å. The addition of pentane to the AVR causes an increasingly large fraction of the large and small nanostructures to grow in size. Only nanostructures resistant to aggregation remain in the pentane-rich phase as the 0 wt % AVR axis is approached. Step changes in aggregation identified from changes in average radius of gyration, scattering

  12. Fumigant and repellent properties of essential oils and component compounds against permethrin-resistant Pediculus humanus capitis (Anoplura: Pediculidae) from Argentina.

    Science.gov (United States)

    Toloza, Ariel Ceferino; Zygadlo, Julio; Cueto, Gastón Mougabure; Biurrun, Fernando; Zerba, Eduardo; Picollo, María Inés

    2006-09-01

    The repeated use of permethrin and other insecticides for the control of head lice, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), during past decades has resulted in the development of marked levels of resistance. Thus, new alternative insecticides are needed for the control of head lice. We studied the fumigant and repellent properties of essential oils from 16 native and exotic plants in Argentina, and 21 chemical components against permethrin-resistant head lice from Argentina. With a direct vapor-exposure bioassay, the most effective oil was from the native Myrcianthes cisplatensis Cambess (Myrtaceae) with a time to 50% knockdown (KT50) of 1.3 min, followed by exotic species, Eucalyptus cinerea F.V. Muell., Eucalyptus viminalis Labill., and Eucalyptus saligna Smith. with KT50 values of 12.0, 14.9, and 17.4 min, respectively. The most effective components were 1,8-cineole and anisole, with KT50 values of 11.1 and 12.7 min, respectively. Regression analysis of KT50 values and vapor pressures and water-partition coefficients for the essential oil components revealed that the most effective fumigants were among the more volatile components. Repellency assays indicated that the essential oil from Mentha pulegium L. and its benzyl alcohol component were the most effective repellents, having repellency indices of 75.5 and 57.8%, respectively. Thus, some Argentinean plants contain essential oils and components that function as fumigants or as repellents and thereby show potential for development of new control products for head lice.

  13. Modeling of Asphaltene Onset Precipitation Conditions with Cubic Plus Association (CPA) and Perturbed Chain Statistical Associating Fluid Theory (PC-SAFT) Equations of State

    DEFF Research Database (Denmark)

    Arya, Alay; Liang, Xiaodong; von Solms, Nicolas

    2016-01-01

    : All three models require the same number of experimental data points (at least three upper onset pressures and one bubble pressure) in order to obtain model parameters.:Different types of asphaltene phase behavior for different reservoir fluids, where asphaltene solubility either decreases...... this study. The sensitivity of SARA data to the modeling approach based On PC-SAFT (WOA) is also analyzed. Finally, the relationship between the binary interaction parameter of the asphaltene-CO2 pair and crossover temperature, below which asphaltene solubility increases in reservoir fluid, with CO2 gas...

  14. EFFECTIVENESS OF THE DERYNG AND CLEVENGER-TYPE APPARATUS IN ISOLATION OF VARIOUS TYPES OF COMPONENTS OF ESSENTIAL OIL FROM THE MUTELINA PURPUREA THELL. FLOWERS.

    Science.gov (United States)

    Baj, Tomasz; Sieniawska, Elwira; Kowalski, Radoslaw; Wesolowskp, Marek; Ulewicz-Magulska, Beata

    2015-01-01

    In this study, both qualitative and quantitative analyses of chemical composition of M. purpurea essential oil obtained in the Deryng and Clevenger-type apparatuses were compared. As a result, content of volatile compounds were: 785.67 mg/mL and 833.33 mg/mL in the oil obtained in the Deryng (D-EO) and Clevenger-type apparatuses (C-EO), respectively. The major components of both essential oils from M. purpurea were: a-pinene, sabinene, myrcene, (Z)-sesquisabinene hydrate, (E)-sesquisabinene hydrate, and a-bis-abolol. The correlation coefficients values are not determined by the differences in the concentrations of the components resulting from the application of two different methods of distillation.

  15. 地椒挥发油化学成分研究%STUDY ON THE ESSENTIAL OIL COMPONENTS IN THYMUS QUINQUECOSTATUS CELAK

    Institute of Scientific and Technical Information of China (English)

    陈光英; 袁艺; 艾在蕙

    2001-01-01

    AIM To analyse the essential oil components of Thymus quinquecostatus Celak. METHODS Gas chromatography/mass spectrometry were used. RESULTS A total of 78 components were separated. 34 of them were identified, which accounted for 95.93% of the total peak area. The main constituents are o-cymene, carvacrol, caryophyllene, 2-isopropyl-1-methoxy-4-methylbenzene and γ-terpene. CONCLUSION Thymus quinquecostatus Celak has perfume and medical development value.

  16. Chemosensory responses to the repellent nepeta essential oil and its major component nepetalactone by the yellow fever mosquito, aedes aegypti, a vector of zika virus

    Science.gov (United States)

    Nepeta essential oil (Neo) (catnip) and its major component, nepetalactone, have long been known to repel insects including mosquitoes. However, the neural mechanisms through which these repellents are detected by mosquitoes, including the yellow fever mosquito Aedes aegypti, an important vector of...

  17. 不同等级橄榄油中挥发性特征成分的研究%Volatile characteristic components in olive oils of different grades

    Institute of Scientific and Technical Information of China (English)

    顾强; 王玥; 陈君义; 乙小娟; 刘一军

    2012-01-01

    The volatile components of olive oils were systematically studied by the method of headspace -solid phase microextraction - GC/MS ( HS - SPME - GC/MS ). Two characteristic components were detected in the chromatogram with retention time of 15.71 min and 19. 98 min by lots of detections and in-tercomparisons and the contents of the components were closely related to the grades of the olive oils. The two volatile characteristic components could indicate the grades of olive oils, and a new method of grade identification of olive oil was developed.%利用顶空-固相微萃取-气相色谱-质谱联用(HS-SPME-GC/MS)法,对不同等级橄榄油中的挥发性成分进行了系统研究.通过大量检测和比对,从色谱图上分辨出两种保留时间分别为15.71 min和19.98 min的特征成分,其含量与橄榄油等级密切相关.该研究工作首次确定了两种能反映橄榄油等级的挥发性特征成分,为开发全新的橄榄油等级鉴别方法奠定了理论基础.

  18. A comparative evaluation of Origanum onites essential oil and its four major components as larvicides against the pine processionary moth, Thaumetopoea wilkinsoni Tams.

    Science.gov (United States)

    Cetin, Huseyin; Erler, Fedai; Yanikoglu, Atila

    2007-08-01

    The pine processionary moth (PPM), Thaumetopoea wilkinsoni Tams. (Lepidoptera: Thaumatopoeidae), is an important forest pest in the Mediterranean area, and urticating hairs of the caterpillars of this species cause allergic reactions on skin of humans and animals. In the present study, the larvicidal activities of Turkish oregano (Origanum onites L.) essential oil and its four major components, carvacrol, gamma-terpinene, terpinen-4-ol and thymol, were evaluated against fourth/fifth-instar larvae of PPM under laboratory conditions. The essential oil was larvicidal to PPM with an LD(50) value of 3800 microL L(-1) when 0.1 mL was applied per larva. Carvacrol was the most toxic component found in the essential oil (LD(50) = 3100 microL L(-1)), followed by thymol (LD(50) = 5500 microL L(-1)). The other two components, gamma-terpinene and terpinen-4-ol, were less effective. The results showed that Turkish oregano essential oil and its two components, carvacrol and thymol, could be potential alternatives to synthetic insecticides for the control of PPM.

  19. Edible olive pomace oil concentrated in triterpenic acids, procedure of physical refining utilised for obtainment thereof and recovery of functional components present in the crude oil

    OpenAIRE

    Ruiz Méndez, Mª Victoria; Dobarganes, M. Carmen; Sánchez Moral, Pedro

    2008-01-01

    Procedure of refining crude olive pomace oil obtained through centrifuging or decantation of the pomace, comprising the stage of filtration of the starting crude olive pomace oil carried out through filters having a pore size comprised in the interval from 0.1 to 20 microns and at a temperature below 70 C, preferentially between 35 and 45 C.

  20. Antibacterial activity and mechanism of action of Monarda punctata essential oil and its main components against common bacterial pathogens in respiratory tract.

    Science.gov (United States)

    Li, Hong; Yang, Tian; Li, Fei-Yan; Yao, Yan; Sun, Zhong-Min

    2014-01-01

    The aim of the current research work was to study the chemical composition of the essential oil of Monarda punctata along with evaluating the essential oil and its major components for their antibacterial effects against some frequently encountered respiratory infection causing pathogens. Gas chromatographic mass spectrometric analysis revealed the presence of 13 chemical constituents with thymol (75.2%), p-cymene (6.7%), limonene (5.4), and carvacrol (3.5%) as the major constituents. The oil composition was dominated by the oxygenated monoterpenes. Antibacterial activity of the essential oil and its major constituents (thymol, p-cymene, limonene) was evaluated against Streptococcus pyogenes, methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pneumoniae, Haemophilus influenzae and Escherichia coli. The study revealed that the essential oil and its constituents exhibited a broad spectrum and variable degree of antibacterial activity against different strains. Among the tested strains, Streptococcus pyogenes, Escherichia coli and Streptococcus pneumoniae were the most susceptible bacterial strain showing lowest MIC and MBC values. Methicillin-resistant Staphylococcus aureus was the most resistant bacterial strain to the essential oil treatment showing relatively higher MIC and MBC values. Scanning electron microscopy revealed that the essential oil induced potent and dose-dependent membrane damage in S. pyogenes and MRSA bacterial strains. The reactive oxygen species generated by the Monarda punctata essential oil were identified using 2', 7'-dichlorofluorescein diacetate (DCFDA).This study indicated that the Monarda punctata essential oil to a great extent and thymol to a lower extent triggered a substantial increase in the ROS levels in S. pyogenes bacterial cultures which ultimately cause membrane damage as revealed by SEM results.

  1. Nematicidal Activity of Plant Essential Oils and Components From Ajowan (Trachyspermum ammi), Allspice (Pimenta dioica) and Litsea (Litsea cubeba) Essential Oils Against Pine Wood Nematode (Bursaphelenchus Xylophilus).

    Science.gov (United States)

    Park, Il-Kwon; Kim, Junheon; Lee, Sang-Gil; Shin, Sang-Chul

    2007-09-01

    Commercial plant essential oils from 26 plant species were tested for their nematicidal activities against the pinewood nematode, Bursaphelenchus xylophilus. Good nematicidal activity against B. xylophilus was achieved with essential oils of ajowan (Trachyspermum ammi), allspice (Pimenta dioica) and litsea (Litsea cubeba). Analysis by gas chromatography-mass spectrometry led to identification of 12, 6 and 16 major compounds from ajowan, allspice and litsea oils, respectively. These compounds from three plant essential oils were tested individually for their nematicidal activities against the pinewood nematode. LC(50) values of geranial, isoeugenol, methyl isoeugenol, eugenol, methyl eugenol and neral against pine wood nematodes were 0.120, 0.200, 0.210, 0.480, 0.517 and 0.525 mg/ml, respectively. The essential oils described herein merit further study as potential nematicides against the pinewood nematode.

  2. Nematicidal activity of plant essential oils and components from coriander (Coriandrum sativum), Oriental sweetgum (Liquidambar orientalis), and valerian (Valeriana wallichii) essential oils against pine wood nematode (Bursaphelenchus xylophilus).

    Science.gov (United States)

    Kim, Junheon; Seo, Sun-Mi; Lee, Sang-Gil; Shin, Sang-Chul; Park, Il-Kwon

    2008-08-27

    Commercial essential oils from 28 plant species were tested for their nematicidal activities against the pine wood nematode, Bursaphelenchus xylophilus. Good nematicidal activity against B. xylophilus was achieved with essential oils of coriander (Coriandrum sativum), Oriental sweetgum (Liquidambar orientalis), and valerian (Valeriana wallichii). Analysis by gas chromatography-mass spectrometry led to the identification of 26, 11, and 4 major compounds from coriander (Coriandrum sativum), Oriental sweetgum (Liquidambar orientalis), and valerian (Valeriana wallichii) oils, respectively. Compounds from each plant essential oil were tested individually for their nematicidal activities against the pine wood nematode. Among the compounds, benzaldehyde, trans-cinnamyl alcohol, cis-asarone, octanal, nonanal, decanal, trans-2-decenal, undecanal, dodecanal, decanol, and trans-2-decen-1-ol showed strong nematicidal activity. The essential oils described herein merit further study as potential nematicides against the pine wood nematode.

  3. Colloidal Structure of Heavy Crudes and Asphaltene Soltutions Structure colloïdale des bruts lourds et des suspensions d'asphaltènes

    Directory of Open Access Journals (Sweden)

    Barre L.

    2006-12-01

    Full Text Available Many industrial problems that arise during petroleum processing are related to the high concentration of asphaltenes. A good knowledge of the chemical composition of these macromolecules and a detailed understanding of the evolution of the colloïdal structures present in oil and its derivatives can play a decisive role in improving processing facilities. Asphaltenes are defined by their insolubility in n-heptane. Soluble molecules are called maltenes which can be fractionated by liquid chromatography in so-called resins, aromatic and saturated fractions. The major part of the research carried out on these complex molecules concerned the chemical composition determination from powerful techniques measurements as for instance IR or NMR methods. Nevertheless, very little information on the colloïdal structure of asphaltenes or resins in pure solvent or in real systems is accessible.The molecular weight determination was the first objective; several techniques, as vapour pressure osmometry (VPO, were used. The main conclusion of these determinations was the huge variation of the molecular weight measured by different methods. We used X-ray and neutron small angle scattering techniques in order to deduce the size polydispersity and the weight average molecular weight. Different systems as (i asphaltenes or resins in solution with different solvents, or (ii asphaltene and resin mixtures in suspension with good or bad solvents were investigated as a function of temperature increase. We have exhibited that the aggregation number, i.e. the number of smaller entities , can strongly vary with solvent composition and temperature. Resins appear as very good solvent for asphaltene molecules. Scattering measurements often exhibit strong scattered intensity at small scattering vector, showing the presence in the suspension of large heterogeneities in diluted solutions of asphaltenes and resins. We can suggest that these heterogeneities are due to

  4. Chemical composition of volatile components, antimicrobial and anticancer activity of n-hexane extract and essential oil from Trachyspermum ammi L. seeds

    Directory of Open Access Journals (Sweden)

    El-Sayed S. Abdel-Hameed

    2014-12-01

    Full Text Available The aim of this study was to characterize the chemical composition of some volatile components, in vitro antimicrobial and anticancer activity of essential oil and n-hexane extract from Trachyspermum ammi L. (Family Apiaceae. The chemical composition of samples was obtained by GC-MS analysis, the antimicrobial activity was evaluated by disc diffusion method whereas the in vitro anticancer activity was evaluated by sulphorhodamine method. Twenty-three monoterpenoide compounds were identified in the essential oil in which four compounds; γ-terpinene, thymol, P-cymene and β-pinene were the major components of the oil with quantity 266.28, 201.97, 194.91 and 38.49 mg/g oil respectively whereas the other nineteen compounds had quantity < 10 mg/g oil. Twelve monoterpene compounds were identified in the n-hexane extract in which three compounds; thymol, γ-terpinene and P-cymene were the major components of volatile components of the n-hexane extract with quantity 138.85, 56.41 and 32.69 mg/g extract respectively whereas the other nine compounds had quantity < 10 mg/g extract. The essential oil and n-hexane extract exhibited an antimicrobial activity against five microorganisms and an anticancer activity against HepG2. The essential oil showed higher activity than the n-hexane. γ- thymol, terpinene and P-cymene of the two samples play an important role in antimicrobial and anticancer activity. In conclusion, this considered the first report that gave the real quantity of each volatile compound in the essential oil and n-hexane extract of T. ammi. Also, this the first work dealing with the anticancer activity of the two samples in addition to the agreement of antimicrobial activity with previous studies. More safety and toxicological studies will need to be addressed if the essential oil and n-hexane extract of T. ammi are to be used for food preservation or medicinal purposes.

  5. Fullerenes in asphaltenes and other carbonaceous materials: natural constituents or laser artifacts.

    Science.gov (United States)

    Santos, Vanessa G; Fasciotti, Maíra; Pudenzi, Marcos A; Klitzke, Clécio F; Nascimento, Heliara L; Pereira, Rosana C L; Bastos, Wagner L; Eberlin, Marcos N

    2016-04-25

    The presence of fullerenes as natural constituents of carbonaceous materials or their formation as laser artifacts during laser desorption ionization (LDI) mass spectrometry (MS) analysis is reinvestigated and reviewed. The results using asphaltene samples with varying composition as well as standard polycyclic aromatic hydrocarbons (PAH) and fullerene samples as models have demonstrated that indeed Cn ring fullerenes are not natural constituents but they are formed as common and often as predominant artifacts upon laser radiation, and a series of incorrect assignments based on LDI-MS data of several carbonaceous materials seems unfortunately to have been made. When the present results are evaluated also in the light of the vast literature on LDI-MS of carbonaceous materials, the formation of fullerene artifacts seems particularly common for LDI-MS analysis of asphaltenes and other carbonaceous samples with considerably high levels of PAH and varies according to the type of laser used, and the intensity of the laser beam.

  6. Analysis of chemical composition of high viscous oils

    Directory of Open Access Journals (Sweden)

    Irina Germanovna Yashchenko

    2014-07-01

    Full Text Available The spatial distribution of viscous oils which are considered as an important reserve for oil-production in future were studied on base of information from global database on oil physical and chemical properties. Changes in chemical composition of viscous oils in different basins and continents were analyzed as well. It is shown, on average, viscous oils are sulfur-bearing, low paraffin, highly resinous oils with an average content of asphaltenes and low content of the fraction boiling at 200 C. Study results of viscous oils peculiarities of Canada, Russia and Venezuela are given. The analysis results can be used to determine the optimal layouts and conditions of oil transportation, to improve the search methods of geochemical exploration, and to solve other problems in the oil chemistry.

  7. Phytochemistry and nematicidal activity of the essential oils from 8 Greek Lamiaceae aromatic plants and 13 terpene components.

    Science.gov (United States)

    Ntalli, Nikoletta G; Ferrari, Federico; Giannakou, Ioannis; Menkissoglu-Spiroudi, Urania

    2010-07-14

    Eight essential oils (EOs) as well as 13 single terpenes were studied for their nematicidal activity against Meloidogyne incognita , for three immersion periods (24, 48, and 96 h). The EOs were isolated from eight Greek Lamiaceae species: Melissa officinalis , Sideritis clandestina , Origanum dictamnus , Ocimum basilicum , Mentha pulegium , Origanum vulgare , Vitex agnus castus , and Salvia officinalis . The EOs nematicidal activity was correlated to their chemical composition as well as to the pure terpenes' activity tested individually. Clear dose and time response relationships were established. The EOs of O. vulgare, O. dictamnus, M. pulegium, and M. officinalis exhibited high nematicidal activity against M. incognita, and the EC(50) values (96 h) were calculated at 1.55, 1.72, 3.15, and 6.15 muL/mL, respectively. The activity of the nematicidal terpenes was found to decrease in the order l-carvone, pulegone, trans-anethole, geraniol, eugenol, carvacrol, thymol, terpinen-4-ol, and the respective EC(50) values (24 h) were calculated in the range of 115-392 mug/mL. Terpenes tested individually were more active than as components in EO, implementing antagonistic action.

  8. Complexation of estragole as pure compound and as main component of basil and tarragon essential oils with cyclodextrins.

    Science.gov (United States)

    Kfoury, Miriana; Auezova, Lizette; Ruellan, Steven; Greige-Gerges, Hélène; Fourmentin, Sophie

    2015-03-15

    Inclusion complexes of estragole (ES) as pure compound and as main component of basil and tarragon essential oils (EOs) with α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (HP-β-CD), randomly methylated-β-cyclodextrin (RAMEB), a low methylated-β-cyclodextrin (CRYSMEB) and γ-cyclodextrin (γ-CD) were characterized. Formation constants (Kf) of the complexes were determined in aqueous solution by nonlinear regression analysis using static headspace gas chromatography (SH-GC) and UV-visible spectroscopy. Solid inclusion complexes were prepared by the freeze-drying method for different CD:ES molar ratios and were characterized by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR). Inclusion complexes formation allowed the controlled release of ES. Moreover, increased DPPH radical scavenging activity and photostability of ES and ES containing EOs (ESEOs) were observed in the presence of CDs. These findings suggest that encapsulation with CDs could be an efficient tool to improve the use of ES and ESEOs in aromatherapy, cosmetic and food fields.

  9. Pulmonary changes induced by trans,trans-2,4-decadienal, a component of cooking oil fumes.

    Science.gov (United States)

    Wang, C-K; Chang, L W; Chang, H; Yang, C-H; Tsai, M-H; Tsai, H-T; Lin, P

    2010-03-01

    Cooking oil fumes (COF) are