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Alkyl phosphonic acids are amphiphilic structures consisting of non-polar organic hydrophobic groups and anionic inorganic hydrophilic groups, which makes them be able to behave as surfactants as well as smart corrosion inhibitors...
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Alkyl phosphonic acids are amphiphilic structures consisting of non-polar organic hydrophobic groups and anionic inorganic hydrophilic groups, which makes them be able to behave as surfactants as well as smart corrosion inhibitors. A simple and high yield (up to 87%) pathway for synthesizing decyl phosphonic acid (DPA) is described._(1)H and_(13)C-NMR) as well as FTIR spectroscopy were used to characterize chemical structures and purity of the obtained product. Thermal properties and crystal structure of DPA were investigated using differential scanning calorimetry analysis (DSC) and thermogravimetric analysis (TGA). The stability of DPA in Oil-in-Water (O/W) and Water-in-Oil (W/O) emulsions was improved in the presence of ammonium persulfate (APS), which allowed us to measure their specific characteristics such as particle size and zeta potential ( ξ ) of micelles. Both emulsions were used for synthesizing polyaniline (PANI) by emulsion polymerization. Wettability of DPA on the mild steel surface was examined using contact angle measurements. Moreover, corrosion-inhibition properties studied by using electrochemical impedance spectroscopy (EIS) technique and salt spray test results revealed that DPA can be an efficient ingredient for anti-corrosion coating.
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The viscosity of water-in-oil and oil-in-water emulsions is a key parameter to understand during oil exploitation and transportation. Water content increases with the extraction of crude oil, especially in the middle and late peri...
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The viscosity of water-in-oil and oil-in-water emulsions is a key parameter to understand during oil exploitation and transportation. Water content increases with the extraction of crude oil, especially in the middle and late periods of exploitation. Apparent viscosity increases as formation water content increases. However, apparent viscosity decreases when the water cut is beyond the phase transition point, after which, the water-in-oil emulsion becomes an oil-in-water emulsion. Many models for calculating the viscosity of W/O emulsions has been proposed, but methods for predicting the viscosity of O/W emulsions are rare. In this article, a method to calculate viscosity of W/O and O/W emulsions based on the Richardson and Taylor equations is introduced. Contrary to the existing correlations, the method presented here takes into account more factors, including water cut, temperature, shear rate, viscosity of oil and formation water. Additionally, whereas conventional correlations have been able to only calculate the viscosity of water-in-oil emulsions, the proposed method can also calculate the viscosity of oil-in-water emulsions. The accuracy and reliability of 5 conventional correlations and of this new method are assessed using the experimental data. The proposed model better fits the data when predicting the viscosity of W/O and O/W emulsions, with average absolute error of 12.71-16.43%.
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Measuring water content is useful in the oil industry to quantify the actual amount of oil being produced. This extent is used in the processes of control and transfer of custody in tank farms, flow stations, and others. In this s...
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Measuring water content is useful in the oil industry to quantify the actual amount of oil being produced. This extent is used in the processes of control and transfer of custody in tank farms, flow stations, and others. In this study, to determine the water content with an admittance measuring device, a characterization was performed with emulsions to identify the behavior of the sensor against this type of fluid. The device has facing electrodes parallel flat. Emulsions O/W and W/O were prepared in the laboratory with heavy oil at laboratory temperature conditions. The capacitance measurement is used to calculate the value of relative permittivity of the fluid (εm) and conductance is used to calculate the conductivity of the mixture (σm). The results of water content measurements showed the sensor response is related to the continuous phases of the emulsions. In addition, these measurements indicated that a characterization of the electrical behavior of the emulsions, as well as the effect of the formulation of the emulsion, can be made using this equipment.
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A strain of Pseudomonas aeruginosa isolated from a site contaminated with refined oil products exhibited demulsification capabilities against Tween 80-Span 80 stabilized oil-in-water (O/W), Tween 80-stabilized water-in-oil (W/O) m...
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A strain of Pseudomonas aeruginosa isolated from a site contaminated with refined oil products exhibited demulsification capabilities against Tween 80-Span 80 stabilized oil-in-water (O/W), Tween 80-stabilized water-in-oil (W/O) model emulsions (kerosene-water), and an industrial emulsion (Daido Dairoll PA-5A). GC-MS analysis confirmed the presence of fatty acids and carbohydrates in the extracellular biodemulsifier. The demulsifying activity of cells and culture supernatants was favored by growth in media containing 1% diesel oil. There was a correlation between culture age, de-emulsification and cellular hydrophobicity, and highest activities were observed for cells and supernatants from 96-h cultures. Activity increased with addition of up to 60. mg cells or 300. μL supernatant to emulsions. The activity was relatively stable at 20-40. °C and to freezing, but was reduced by 69% by washing the cells with chloroform-methanol-water. This demulsifier has potential for application in biotreatment of emulsified oily wastewaters to promote recovery and/or degradation of oil.
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Emulsions frequently encountered in petroleum production, include water-in-oil (W/O) emulsions, oil-in-water (O/W) emulsions, and water-in-oil-in-water (W/O/W) emulsions, which considerably increase operation and production costs ...
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Emulsions frequently encountered in petroleum production, include water-in-oil (W/O) emulsions, oil-in-water (O/W) emulsions, and water-in-oil-in-water (W/O/W) emulsions, which considerably increase operation and production costs and cause technical challenges such as fouling and corrosion. Chemical treatment as a primary method has been extensively applied to destabilize the highly stable and complex emulsions. Demulsifiers play a vital role in demulsification efficiency of the chemical treatment, while developing effective and cost-efficient demulsifiers remains challenging due to complexity of the emulsions and poorly-understood demulsification mechanisms. This work systematically reviews the stabilization mechanisms of the complex emulsions, including the presence of interface-active species and their effects on the intermolecular and surface forces involved, properties of oil/water interface, and bulk properties of the emulsions. According to the different stabilization mechanisms of W/O emulsions and O/W emulsions, we subdivide demulsifiers into emulsion breakers (EBs) applied to demulsify W/O emulsions and reverse emulsion breakers (REBs) for O/W emulsions. The two types of demulsifiers are comprehensively reviewed and discussed, including types, influencing factors, demulsification mechanisms, and overdose effects. Our work provides useful insights into the fundamental stabilization and destabilization mechanisms of W/O emulsions and O/W emulsions and improves the understanding of efficient EBs and REBs and their applications in crude oil production and other related chemical and environmental engineering processes.y
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The purpose of the article is to present practical, technical and ecological challenges in the pretreatment/treatment technologies of spent oil waste that are oil-in-water emulsion systems containing high volumes of water difficul...
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The purpose of the article is to present practical, technical and ecological challenges in the pretreatment/treatment technologies of spent oil waste that are oil-in-water emulsion systems containing high volumes of water difficult to be temporary stored. A set of experimental tests on representative oil-in-water spent emulsions have been realized based on a set of treatment screening criteria so that any oil-waste producer/holder can use them to find best pretreatment solutions preventing on-site oil waste generation and preserving in the same time depletion of non-renewable natural resources by recovery of valuable components in the context of sustainable development.
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Water-in-oil mixtures from more than 300 crude oils and petroleum products were made in the laboratory and studied over time. More than 140 of these yielded products resembling emulsion. Water-in-oil types were characterized by re...
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Water-in-oil mixtures from more than 300 crude oils and petroleum products were made in the laboratory and studied over time. More than 140 of these yielded products resembling emulsion. Water-in-oil types were characterized by resolution of water at I and 7 days, and some after I year. Rheology measurements were carried out at the same intervals. The objective of the study was to characterize the water-in-oil types and relate these to starting oil properties. It was found that water-in-oil types can be grouped into four categories: stable, unstable, meso-stable and entrained. Each of these has distinct physical properties. A stable emulsion remains so for at least 30 days and takes up typically 80% water. The viscosity of a stable emulsion is at least two orders-of-magnitude greater than that of the starting oil. An unstable emulsion does not retain water volume greater than 10%. Foran unstable emulsion, the viscosity is typically less than two times greater than the viscosity of the starting oil. A meso-stable emulsion has properties between unstable and stable emulsions and typically takes up 60% water. breaking down within 7 days, losing most of this water. A meso-stable emulsion usually has a viscosity no more than one order-of-magnitude greater than that of the starting oil. Another retention mechanism for water in oil is that of viscous entrainment of water droplets. This type of water uptake, not a true emulsion, has been called entrained. Entrained water to the extent of typically 45% is taken up initially and this water content declines slowly over a period of days. A stability index was developed to characterize these water-in-oil types. This consists of the product of the ratio of viscosity increase and a ratio of the elasticity increase. This index was used to describe the water-in-oil types and to correlate stability with starting oil composition and properties. A comparison of the properties of the starting oils before mixing with water shows that the most important factors for water uptake and emulsion formation are asphaltene and resin content, starting oil viscosity and density. Other factors that are shown to be important are the saturate content and asphaltene-to-resin ratio. The relationship between these factors and stability gives insights into the nature of water-in-oil types and emulsions.
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Developing a membrane integrating high separation efficiency and good anti-fouling ability for both oil-in-water and water-in-oil emulsions is meaningful due to the complexity and diversity of actual oily wastewater. Herein, a fac...
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Developing a membrane integrating high separation efficiency and good anti-fouling ability for both oil-in-water and water-in-oil emulsions is meaningful due to the complexity and diversity of actual oily wastewater. Herein, a facile strategy was designed to generate a nanofibrous Janus membrane to achieve multifunctional and self-cleaning properties. Hydrophilic B-FeOOH was anchored on poly(vinylidene fluoride-co-hexa-fluoropropylene) (PVDF-HEP) fibers to achieve hydrophilicity and self-cleaning performance of PVDF-HEP/B-FeOOH layer by in situ mineralization technology. The Janus membrane was then obtained by incorporating PVDF-HEP fibers layer onto the hydrophilic layer through electrospinning technology. PVDF-HEP/B-FeOOH layer owns super-hydrophilicity (WCA = 0°) and underwater superoleophobicity (OCA = 159°), which can separate different surfactant-stabilized oil-in-water emulsions with separation efficiency of above 99.8 % when this layer is facing up. Conversely, the PVDF-HEP layer exhibits superhydrophobicity (WCA = 149°), which can separate different surfactant-stabilized water-in-oil emulsions with separation efficiency of above 99 % when this layer is facing up. More importantly, a satisfying water flux recovery rate of 98.2 % is acquired due to the synergistic effect between B-FeOOH photocatalysis and asymmetric wettability of the membrane, endowing the membrane with effective self-cleaning capability and satisfactory stability. This study provides a new strategy for designing multifunctional membrane toward actual complex oily wastewater treatment.
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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 charac...
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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. Rhe-ology 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 emulsiflcation is a result of physical stabilization by oil viscosity and chemical stabilization by asphalt-enes 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.
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The efficacy of electrocoalescence is critically dependent upon the interfacial tension of the crude-water interface. This study demonstrates the effect of interfacial tension on the electrocoalescence efficiency in crudes with hi...
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The efficacy of electrocoalescence is critically dependent upon the interfacial tension of the crude-water interface. This study demonstrates the effect of interfacial tension on the electrocoalescence efficiency in crudes with high acidity. The interfacial tension is estimated using spinning drop tensiometer (SDT) and electrocoalescence experiments are performed at an electric field = 1.15 kV(rms)/cm at a frequency of 50 Hz. It is observed that separation of water from the crude is hindered at high pH for two very different reasons depending upon the source of alkalinity. Calcium hydroxide induced alkalinity leads to more rigid interface, resulting in delayed electrocoalescence. On the other hand, sodium hydroxide based alkalinity leads to ultra-low tension of crude-water interface, thereby causing oil-in-water emulsion. Increase in the pH also leads to poor quality of brine resolution, in case of sodium hydroxide based alkalinity (pH = 10) we get unresolved turbid emulsion.
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