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Showing 1 to 20 of 48 for “"asphaltenes"”.
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Adsorption & Adhesion of Asphaltenes at Complex Interfaces: An AFM Approach
Asphaltenes are the heaviest fraction of crude oil, pinpointed as the culprit for the fouling of components throughout the hydrocarbon value chain. The ill-defined nature of asphaltenes has challenged scientists and industry alike, to determine their molecular composition and mitigate their effects …
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Precipitation, Aggregation, and Settling of Asphaltenes from n-Alkane Diluted Bitumens
… the precipitation, aggregation, and settling of asphaltenes from solvent diluted bitumen. Models and data that include the effect of solvent type, concentration, shear, and contact time on asphaltene precipitation and settling are required to design and optimize these processes but are lacking or …
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New Pathways for Asphaltenes Upgrading via Oxy-cracking in Liquid Phase
Surplus asphaltenes production in northern Alberta facilities, led to searching new pathways to process asphaltenes pitches as the most challenging material in heavy oils. Due to the additional expenses these compounds could cause as a result of precipitation at flow lines, well bore and production …
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Geochemical study on reservoir and source rock asphaltenes and their significance for hydrocarbon generation
Erdölasphaltene, Muttergesteinsasphaltene und Muttergesteinskerogene wurden mittels verschiedener analytischer Pyrolysetechniken bezüglich ihres Kohlenwasserstoff-genesepotentials untersucht. Besonderes Interesse wurde hierbei der kompositionellen Zusammensetzung der generierten Kohlenwasserstoffe …
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MASS SPECTROMETRIC INVESTIGATIONS OF STRUCTURALLY DIAGNOSTIC ION-MOLECULE REACTIONS AND OF MOLECULAR STRUCTURES OF ASPHALTENES
Tandem mass spectrometry (MS/MS) has proven to be a powerful tool for the molecular-level characterization of components of complex mixtures due to its ability to study ionized molecules with high sensitivity, selectivity and specificity. By combining MS/MS with liquid chromatography (LC) to enable …
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New Insights into the Mitigation of Asphaltene Deposition and the Utilization of Asphaltene Deposits
… reinjection of dead oil. It is well known that asphaltenes are a polydisperse mixture of molecules with a broad distribution of sizes and molecular characteristics. However, for simplicity asphaltenes have been assumed to be a monodisperse mixture and their deposition tendency has been evaluated …
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Investigations of Asphaltene-Metal Interactions
Asphaltenes are the most polar fraction of petroleum that can precipitate due to changes in pressure, temperature and composition which may be encountered during petroleum production and transportation. The precipitated asphaltenes can subsequently deposit on the surfaces of …
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Emerging electronic materials : thin films of asphaltenes and coal nanoparticles for electronic devices and large area layer controlled 2-dimensional semiconductor synthesis
… I prepared from source material such as coal and asphaltenes. The second are two dimensional materials in particular transition metal dichalcogenides. Following an introduction to the materials I have studied in chapter 1, in chapters 2 and 3 I will discuss a class of materials which have seen …
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Insights into asphaltene stability, aggregation, deposition and molecular structure
Asphaltenes are the heaviest, most polar, and most surface-active species of crude oils which are fairly stable in the oil; however, a small variation in the pressure, composition, and temperature can cause asphaltene phase instability and alteration in their solubility parameter and can …
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Investigation of Asphaltene Adsorption at Liquid-Liquid and Liquid-Solid Interfaces
<p>Asphaltenes, as indigenous components in crude oils, are believed to play an important role in the petroleum production and processing industry. For example, asphaltene molecules can adsorb onto the water / oil interface like the amphiphiles and hinder water droplet coalescence, resulting in the …
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Mass Spectrometric Studies on the Primary Products of Fast Pyrolysis of Carbohydrates and the Molecular Structures of Asphaltenes, and the Development of a Rastering Probe for Laser-Induced Acoustic Desorption into an Atmospheric Pressure Chemical Ionization Source
… is known about the structures of molecules in asphaltenes, the heaviest fraction of crude oil and one of the most complex mixtures in nature. Elucidating the structures of the compounds present in these mixtures is important for the rational design of methods to prevent the problems the …
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MASS SPECTROMETRIC STUDIES ON PETROLEUM ASPHALTENES AND ORGANOSULFUR COMPOUNDS, ON FUNCTIONAL-GROUP SELECTIVE ION-MOLECULE REACTIONS AND ON GAS-PHASE REACTIVITY OF META-BENZYNES TOWARD AMINO ACIDS
… molecular weight or structural information of asphaltenes, which are the heaviest components of crude oil and one of the most complex mixtures in nature. Characterization of asphaltenes at the molecular level can alleviate some of the problems they cause to petroleum industry and facilitate the …
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Reactivity Studies of Tridhydropyridine Radical Cautions by using Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry and Advancement of Mass Spectrometric Analysis of Asphaltenes and Degradation Products
… behavior of ionized synthetic model compound of asphaltenes. The CAD studies of ionized molecules with fused aromatic ring systems, such as 9-dodecylanthracene, dodecylpyrene, 9-hexylnaphthalene and hexylpyrene, show exclusively benzylic bond cleavages. However, the alkyl side chains of ionized …
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Microchemical systems for understanding of multiphase flows in upstream hydrocarbon and natural gas productions
… number. The deposition and dissolution of asphaltenes in porous media, an important problem in science and macromolecular engineering, was for the first time investigated in a transparent packed-bed microreactor (μPBR) with online analytics to generate high-throughput information. Residence …
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Characterization and Asphaltene Precipitation Modeling of Native and Reacted Crude Oils
… from thermocracking and hydrocracking processes. Asphaltenes can precipitate with changes in pressure, temperature and composition, promoting problems with deposition and fouling during crude oil operations. Fouling problems are a key concern in the oil industry because of their associated cost …
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Role of Aqueous Phase Chemistry, Interfacial Film Properties, and Surface Coverage in Stabilizing Water-In-Bitumen Emulsions
… Na2CO3). The organic phases consisted of either asphaltenes or bitumen dissolved in solutions of heptane and toluene. Salt contents as low as 0.02 wt% (or 0.03M ionic strength) were found to significantly increase the stability of the emulsions regardless of the type of salt present in the …
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New insight into the coordination and reactivity of hetero-substituted maltol and method development for complex mixture analysis of asphaltene.
… development of a new method for investigating asphaltenes, the heaviest and most problematic fraction of crude oil, by NMR spectroscopy and mass spectrometry. To study asphaltenes by mass spectrometry, we reacted a sample of asphaltene with elemental bromine (Br2). This was done to selectively …
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Caracterização estrutural, dinâmica e reológica de suspensões coloidais via simulação molecular
… deposition of heavier fractions, paraffins and asphaltenes, cause problems related to flow assurance. In the early stages of solid precipitation process gels and/or colloidal suspensions are formed. It is necessary studiyng the particle aggregation dynamics to understanding the dynamic …
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Separation and characterization of crude oils and investigation of their wetting properties on rock surfaces
… fractions: Saturates, Aromatics, Resins, and Asphaltenes. Currently, some of the available methods for SARA separation are based on chromatographic principles that may possess some limitations, including requiring the solvent and sample in large amounts, being a time-consuming process, and …
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