Heavy Crude Oil Emulsions Research Articles

Facile preparation of multi-functionalized zwitterionic surfactants for the separation of water in Arabian heavy crude oil emulsions

We report an easy process to prepare new anionic and zwitterionic surfactants to break water in Arabian heavy crude oil emulsions (W/O) with different compositions (10/90, 30/70 and 50/50 vol%). Surfactants were prepared in only two stages using simple methodology. Diethylenetriamine was interacted with three moles of glycidyl 4-nonyl ether followed by the interaction with 3 and 8 mol of 1,3-propanesultone to yield TNDTS-3 and TNDTS-8 respectively. FTIR and NMR spectroscopies were carried out to substantiate the chemical structures of surfactants. Relative solubility number (RSN), surface activity and solubility properties were determined. Demulsification efficiencies and interfacial tension (IFT) of the prepared surfactants were investigated. Our findings demonstrated that increasing propyl sulfonate groups in the surfactant structure improved water solubility, IFT activity and demulsification efficiency. TNDTS-8 achieved 100 % demulsification activities in all W/O emulsions (10/90, 30/70 and 50/50 vol%).

Demulsification Methods for Heavy Crude Oil Emulsions. A Review

Demulsification (dehydration) is one of the most important problems in the oil industry. The peculiarity of heavy oil emulsions is their high stability since heavy crude contains a significant quantity of resins and asphaltenes. This paper provides an overview of the issue of heavy oil emulsion dehydration, emphasizing the importance of understanding their properties to develop appropriate demulsification methods. The use of environmentally friendly demulsifiers was an object of special attention. The analysis of ongoing research in this area would be useful for researches and engineers.

The Synthesis and Application of Novel, Star-Shaped Surfactants for the Destabilization of Water in Arabian Heavy Crude Oil Emulsions

Water in heavy crude oil (W/O) emulsions, which are stubborn mixtures of immiscible heavy crude oil and brine, are a ubiquitous challenge in the petroleum industry. They cause serious corrosion problems, increase the viscosity of petroleum and make the production cost very high. This phenomenon appears during the production of crude oil and should be treated to maximize the overall profitability of oil production and meet transportation requirement. Surfactants are some of the most useful demulsifiers and play a pivotal role in breaking brine/oil emulsions. Herein, we aimed to combine ethyleneamine units and ethyleneoxide units to prepare star-shaped surfactants and test the effect of this combination on the demulsification performance. First, diethylenetriamine reacted with glycidyl 4-nonyl ether (GNE) through an epoxy ring opening to prepare trinonyl phenoxy diethylenetriamine (TNDT). Then, ethylene oxide units were introduced via the interaction of hydroxyl groups with 2-(2-chloroethoxy)ethanol to form ethoxylated trinonyl phenoxy diethylenetriamine (ETNDT). The chemical structures of the surfactants were verified via FTIR and NMR characteristic techniques. The surfactants were applied as demulsifiers for W/O emulsions. It was found that the introduction of the ethyleneoxide units enhanced the solubility of the water and the demulsification performance of the prepared surfactants. The demulsification efficiency was enhanced via ethoxylation and reached 100% for ETNDT for most of the W/O emulsions.

Dimer acid used as CO2‐responsive surfactant for reducing viscosity of heavy crude oil

AbstractThe efficacy of CO2‐switchable surfactants in reducing viscosity of heavy crude oil has received widespread attention due to its switchable surface activity for constructing reversible emulsion. However, the intricate synthesis processes of these surfactants pose a significant challenge in their practical application. The present investigation involved the preparation of surfactants that are responsive to CO2, specifically dimer acid (DA)/tetramethylpropylenediamine (TMPDA), through a facile mixing approach. These surfactants were subsequently employed to mitigate the high viscosity of heavy crude oil. The study employed a surface tension meter to examine the surface behavior of DA/TMPDA, which demonstrated the potential for reducing viscosity. The study examined the CO2 responsiveness of DA/TMPDA through the application of alternating CO2 and N2. It confirmed the reversible CO2 responsiveness of the surface activator. The results from the emulsification and viscosity reduction assessments suggest that the amalgamation of DA and TMPDA in a 1:1 molar ratio yielded a surfactant. This surfactant demonstrated favorable stability in water and heavy crude oil emulsions, as well as low viscosity and rapid emulsion breaking upon exposure to CO2. This investigation demonstrates that it is feasible to produce surfactants that are responsive to CO2 and possess the ability to reduce viscosity through a straightforward mixing process. This presents a viable approach to utilizing oligomeric surfactants that are CO2‐responsive for the purposes of emulsifying and breaking down heavy crude oil.

Efficient Demulsification of Heavy Crude Oil Emulsions Using Bio‐Based Amphiphilic Esters

AbstractAbietic acid (AA) as a natural compound is used to synthesize two amphiphilic esters. AA was reacted with tetraethylene glycol (TG) or polyethylene glycol (PEG‐400) to obtain amphiphilic esters, AA‐TG, and AA‐PG, respectively. AA‐TG and AA‐PG were characterized using different techniques. In addition, the efficacy of these esters in demulsifying water‐in‐heavy crude oil emulsions was evaluated by means of several parameters. The demulsification efficacy (DE) of AA‐TG and AA‐PG reached 100 % in different cases. The results indicated that the DE was improved as the demulsifier concentration and temperature increased and the seawater ratio decreased. Furthermore, AA‐TG and AA‐PG achieved a higher DE and shorter demulsification time than the commercial demulsifier.

One-Step Synthesis of New Amphiphilic Nonionic Surfactants Based on Alkylamine and Poly(ethylene glycol) Dimethacrylate for Demulsification of Arabian Heavy Crude Oil Emulsions.

New non-ionic surfactants based on alkylamine and poly(ethylene glycol) dimethacrylate were synthesized by one-step Aza-Michael addition reaction. The surfactants' chemical compositions, surface and interfacial activities, micellization, and zeta potential were characterized. Their surface and interfacial activities recommended the application as demulsifiers for water in Arabian heavy oil emulsions (w/o). The demulsification of this type of emulsion has attracted researchers' attention because of its high stability with water droplets in the microscale. The outcome of using the prepared surfactants showed high performance as emulsion breakers, as the demulsification efficiency reached 100% for w/o emulsions with different water to oil ratios (50:50, 30:70, and 10:90).

Synthesis, characterization, and application of two new ionic liquids for the dehydration of heavy crude oil emulsions

This work aims at synthesizing two new ionic liquids (ILs) based on the reaction of dodecylamine (DA) with epichlorohydrin (EH), followed by the reaction with either diethylenetriamine (DT) or tetraethylenepentamine (TP) to form the corresponding oligoamines, DADT and DATP, respectively. DADT and DATP were quaternized using acetic acid, producing ILs, DADT-IL, and DATP-IL, respectively. The chemical structures, thermal stability, surface, and interfacial tensions, and relative solubility number (RSN) were evaluated. The efficiency of the as-synthesized ILs for dehydration of water-in-heavy crude oil (W/O) emulsions was also evaluated. Furthermore, the effect of the as-synthesized ILs concentration and the ratio of crude oil to brine on dehydration efficiency was also evaluated. DADT-IL and DATP-IL exhibited promising results for dehydration of W/O emulsions even at low concentrations. The results also indicate that DATP-IL has higher dehydration efficiency, which may be reflected in its higher ability to reduce interfacial tension compared to DADT-IL.

Alginate-based poly ionic liquids for the efficient demulsification of water in heavy crude oil emulsions

This work deals with the synthesis, characterization, and application of alginate-based poly ionic liquids for efficient demulsification of water in oil emulsions. For the formation of renewable poly ionic liquid (PIL), sodium alginate (S.ALG) was converted to alginic acid (H.ALG), followed by an esterification process to produce corresponding polyester, (N.ALG). In the later stages, the formed N.ALG was subjected to a quaternization reaction using either 1-bromohexadecane or 1-bromononane in order to produce PILs (BH-ALG) and (BN-ALG), respectively. Then, the two formed PILs (BH-ALG and BN-ALG) were evaluated in terms of the chemical structure, surface and interfacial tensions, thermal stability, relative solubility number (RSN), and micelle size. While testing the efficiency of as-synthesized two PILs towards the demulsification of water in heavy crude oil (W/O) emulsions, both PILs were found to be efficient. Furthermore, an increase in efficiency was observed with the increase of PIL concentration and ratio of water in the emulsions. Among the two PILs, the BH-ALG displayed higher demulsification efficiency as against the BN-ALG, and this can be due to its higher hydrophobicity, and hence its ability to disperse in heavy crude oil as a continuous phase.

Synthesis and application of novel gemini pyridinium ionic liquids as demulsifiers for arabian heavy crude oil emulsions

Ionic liquids (ILs) are environmentally friendly compounds and their gemini types exhibit high thermal stabilities and high surface and interfacial activity. The main objective of this work is to prepare, characterize and investigate the demulsification efficiency of two gemini pyridinium surfactant ILs. They were prepared by the introduction of long chain decanoyl chloride to aminopyridine followed by quaternization with two dichloro spacers containing different ethylene oxide units (DCDE and TEGDC) to form MEGPy and TEGPy ILs, respectively. The structure properties of the prepared demulsifiers were investigated using different spectral tools including 1HNMR and 13CNMR and DLS. Also, their solubility and surface activity were investigated to confirm their ability to reduce surface tension (ST) and interfacial tension (IFT). Gemini pyridinium IL with triethylene oxide spacer (TEGP) showed higher ability to reduce both ST and IFT than that with mono ethylene oxide spacer (MEGP). Thanks to the ability of both TEGPy and MEGPy surfactant IL to reduce ST and IFT, they were applied successfully as demulsifiers for W/O emulsions with different water percentages. Demulsification study indicated that both TEGPy and MEGPy were able to demusify W/O emulsions with high performance which reached to 100% at low concentrations (250 ppm) for some compositions with higher activity to TEGP IL than MEGPy surfactant.

Demulsification of Heavy Petroleum Emulsion Using Pyridinium Ionic Liquids with Distinct Anion Branching

The challenges associated with heavy crude oil emulsions during hydrocarbon exploitation cannot be overemphasized. As such, water/crude oil separation in oil fields becomes necessary before conveyance to the refinery. In this study, we investigated new classes of pyridinium ionic liquids (ILs) demulsifiers, 1-butyl-4-methylpyridinium tetrafluoroborate, 1-butyl-4-methylpyridinium hexafluorophosphate, and 1-butyl-4-methylpyridinium iodide, designated as BMPT, BMPH, and BMPI, with unique anions (BF4–, PF6–, and I–), respectively. The effects of concentration dosages (100–1000 ppm) and anions of these ILs on the demulsification of produced emulsions were assessed using the bottle test technique at 75 °C. Viscosity and shear stress determination as well as interfacial tension (IFT) measurements were applied to affirm the effectiveness of these ILs to separate water/oil into phases. Bottle test results revealed that BMPT, BMPH, and BMPI demulsifiers removed water from the emulsion effectively, and the demulsification efficiency (% DE) increased with increasing dosage. BMPT, BMPH, and BMPI achieved the best % DE of 84%, 99%, and 59%, respectively, at 1000 ppm after 60 min. The highest water separation was recorded in PF6– anion because of its high hydrophobic nature. Viscosity and shear stress time-sweep measurements indicated the reduction in viscosities and shear stresses after injection of the demulsifiers. Also, the dynamic IFT results showed that these demulsifiers could mix with water–oil at the interface, break asphaltenes and resins molecules, and reduced the IFT from 16.01 to 12.47 mN/m. Optical microscopic emulsion images before and after demulsifier injection and the demulsification mechanism describing the water/oil separation stages are also discussed.

Novel Bio-Based Amphiphilic Ionic Liquids for the Efficient Demulsification of Heavy Crude Oil Emulsions.

In the last few decades, there has been an increasing trend for the usage of natural products and their derivatives as green and renewable oil-filed chemicals. Use of these compounds or their derivatives contributes to reducing the use of traditional chemicals, and enhances green chemistry principles. Curcumin (CRC) is one of the most popular natural products and is widely available. The green character, antioxidant action, and low cost of CRC prompt its use in several applications. In the present study, Curcumin was used to synthesize two new amphiphilic ionic liquids (AILs) by reacting with 1,3-propanesultone or bromoacetic acid to produce corresponding sulfonic and carboxylic acids, CRC-PS and CRC-BA, respectively. Following this, the formed CRC-PS and CRC-BA were allowed to react with 12-(2-hydroxyethyl)-15-(4-nonylphenoxy)-3,6,9-trioxa-12-azapentadecane-1,14-diol (HNTA) to form corresponding AILs, GCP-IL and GRB-IL, respectively. The chemical structures, surface tension, interfacial tension, and relative solubility number (RSN) of the synthesized AILs were investigated. The efficiency of GCP-IL and GRB-IL to demulsify water in heavy crude oil (W/O) emulsions was also investigated, where we observed that both GCP-IL and GRB-IL served as high-efficiency demulsifiers and the efficiency increased with a decreased ratio of water in W/O emulsion. Moreover, the data showed an increased efficiency of these AILs with an increased concentration. Among the two AILs, under testing conditions, GCP-IL exhibited a higher efficiency, shorter demulsification time, and cleaner demulsified water.

Demulsification of stable seawater/Arabian heavy crude oil emulsions using star-like tricationic pyridinium ionic liquids

Green oil-field chemicals based on ionic liquids (ILs) are highly recommended as demulsifiers for heavy crude oil emulsions due to their low vapor pressure, high thermal and chemical stability against degradation in harsh processing conditions. Novel multifunctional tricationic pyridinium ionic liquids (TCPyILs) were synthesized by the reaction of cyanuric chloride with tetraethylene glycol followed by its linking with quaternized aminopyridinium bromide using Bis(chloroethyl) ether as a linker. The chemical structures, surface and interfacial activities and thermal stabilities of the prepared pyridinium ILs were investigated. The amphiphilicity, surface and interfacial activity of the prepared TCPyILs recommended their application as chemical additives in petroleum industry. To the best of our knowledge, it is the first time to apply TCPyILs as demulsifiers for W/O emulsions with high stability and low droplet size (around 2 μm). Comparing with traditional monocationic pyridinium ILs, the prepared TCPyILs had higher efficiencies to demulsify W/O emulsions with different Vol %. The effects of alkyl chain lengths, demulsifier doses and RSN values on the demulsification activities were studied. The results indicated that TCPyILs with nonyl and tetradecyl alkyl chains had better and higher demulsification efficiency comparing with those containing hexadecyl alkyl chains. The demulsification efficiencies of TNPy and TTPy ILs for W/O (50/50, 30/70 and 10/90 vol%) reached 100% even at low concentrations.

Morphology and Rheology of Heavy Crude Oil/Water Emulsions Stabilized by Microfibrillated Cellulose

The application of microfibrillated cellulose and sodium dodecyl sulfate (SDS) to obtain heavy crude oil emulsions in water has been considered. First of all, the optimal concentration of cellulose...

Fabrication of New Demulsifiers Employing the Waste Polyethylene Terephthalate and their Demulsification Efficiency for Heavy Crude Oil Emulsions.

Two novel amphiphilic polyethylene amine terephthalate have been prepared via the glycolsis of polyethylene terephthalate (PET). The product, bis (2-hydroxyethyl terephthalate) (BHET), was converted to the corresponding dialkyl halide, bis(2-chloroethyl) terephthalate (BCET), using thionyl chloride (TC). This dialkyl compound was used for alkylation of dodecyl amine (DOA) and tetraethylenepentamine (TEPA) or pentaethylenehexamine (PEHA) to form the corresponding polyethylene amine terephthalate, i.e., DOAT and DOAP, respectively. Their chemical structure, surface tension, interfacial tension (IFT), and dynamic light scattering (DLS) were determined using different techniques. The efficiency of the prepared polyethylene amine terephthalate to demulsify water in heavy crude (W/O) emulsions was also determined and found to increase as their concentrations increased. Moreover, DOAT showed faster and higher efficiency, and cleaner separation than DOAP.

Dehydration of heavy crude oil emulsions using novel imidazolium-based poly ionic liquids

Sea water/ heavy crude oil emulsions are highly stable and cause serious industrial problems. Amphiphilic poly ionic liquids (ILs) as environmentally safe chemicals can be used as highly efficient demulsifiers to for W/O emulsions. In the present work, two imidazolium-based poly ionic liquids (IMPIL-1 and IMPIL-2) were prepared via one pot modified Debus-Radziszewski reaction by the interaction of triethylenetetramine or diethylenetriamine with glyoxal and formaldhyde in aqeous acetic acid solution. The prepared PILs were after that reacted with glycidyl 4-nonylphenyl ether through the epoxy ring opening to produce two amphiphilic PILs. 1HNMR, DLS and drop shape analyzer were utilized to verify their chemical structures and surface properties of the prepared PILs. The surface properties of AIMPIL-1 and AIMPIL-2 and their ability to reduce the IFT of sea water/ crude oil interface recommended their application as demulsfiers for W/O emulsions. Factors affecting the demulsification properties like relative solubility index, Demulsifier dose and separation time were investigated. The results confirmed the high efficiency of AIMPIL-1 and AIMPIL-2 to act as demulsifiers for W/O emulsions with a priority to the less aminated AIMPIL-1 that reached 100% for emulsion compositions (30/70 and 10/90 vol%).

New amphiphilic pyridinium ionic liquids for demulsification of water Arabic heavy crude oil emulsions

Recently ionic liquids (ILs) have been approved recognition as environmentally safe chemicals in a wide variety of applications including petroleum industry. In the present work, new amphiphilic pyridinium ILs were synthesized via the reaction of 4-amino pyridine with 1-bromotetradecane to form quaternized amino pyridinium bromide followed by ethoxylation of the amino group to form ethoxylate amino pyridinium bromide IL (QEP). Finally, QEP was quaternized using triflouroacetic acid to produce diquaternized pyridinium bromide IL (DQEP). The surface activities of the prepared pyridinium ILs were determined in their aqueous solutions to confirm the amphiphilicity of QEP and DQEP ILs. Zeta potential measurements were also carried out to verify the positive charges on the IL colloids in their aqueous solutions. Relative solubility number values of QEP and DQEP ILs were measured to show the higher hydrophobicity of DQEP than QEP. The prepared ILs were applied as demulsifiers for water in petroleum crude oil (W/O) emulsions having different compositions. The demulsification mechanism of QEP and DQEP ILs were investigated using optical microscope, interfacial tension (IFT), RSN measurements and ILs/asphaltene interactions. The presence of QEP and DQEP was reduced the IFT to confirm their abilities on interaction with the asphaltene layer at interface to successfully dehydrate W/O emulsions. The demulsification efficiencies of QEP and DQEP reached 100% for W/O emulsion (50/50 vol%) and (30/70 and 10/90 vol%), respectively to confirm the ability of these pyridinium ILs to be applied as demulsifiers for crude oil emulsions.

One-Step Synthesis of Amphiphilic Nonylphenol Polyethyleneimine for Demulsification of Water in Heavy Crude Oil Emulsions.

The demulsification of water-in-heavy crude oil emulsion with water droplet size in the microscale has drawn great attention because of their high stability and difficulty of separation. In the present work, a series of ethylene amine-based demulsifiers were prepared in one step through the interaction of pentaethylene hexamine, tetraethylene pentamine, and triethylene tetramene with glycidyl 4-nonylphenyl ether. The amphiphilic polyethyleneimine (APEI) abbreviated as DNPA-6, DNPA-5, and DNPA-4 were prepared to adjust their hydrophile–lipophile balances (HLB) to meet the requirement of the demulsification. 1HNMR, 13CNMR, and FTIR spectra were utilized to verify their chemical structures. The surface properties and zeta potential were also investigated. Demulsifier dose, separation time, and HLB values were taken into account to evaluate the demulsification efficiency of the synthesized APEI. The results suggested that the prepared demulsifiers had high ability to reduce the surface and interfacial tensions and also broke successfully water-in-Arabian heavy crude oil emulsions. The demulsification efficiency of DNPA-5 reached 100% for crude oil/water emulsion (90/10 vol %).

Demulsification of Colombian Heavy Crude Oil (W/O) Emulsions: Insights into the Instability Mechanisms, Chemical Structure, and Performance of Different Commercial Demulsifiers

Chemical products such as PEO/PPO block copolymers or alkoxylated resins tend to work well in chemical demulsification of light hydrocarbons (°API > 20) but fail to do so in the presence of heavy a...

Demulsification of water in heavy crude oil emulsion using a new amphiphilic ionic liquid based on the glycolysis of polyethylene terephthalate waste

Abstract A new amphiphilic ionic liquid (IL) was prepared based on the glycolysis product of polyethylene terephthalate (PET) waste. Bis(2-hydroxyethyl) terephthalate (BHET) produced from glycolysis of PET was converted into bis(2-chloroethyl) terephthalate (BCET). The glycidyl 4-nonylphenyl ether (GNE) was reacted with ethanol amine (EA) to form the corresponding amine, 1-((2-hydroxyethyl)amino)-3-(4-nonylphenoxy)propan-2-ol, (HANP) and the formed amine was then ethoxylated using tetraethylene glycol (TEG) to form ethoxylated amine (EHANP). The EHANP was quaternized by BCET to form the corresponding ionic liquid (EHANP-IL). Following the synthesis, the chemical structure was confirmed by Fourier-transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance (1H NMR). The surface activity and dynamic light scattering (DLS) properties were also investigated. Further, the demulsification efficiencies of synthesized IL and EHANP was evaluated and found that the EHANP-IL was able to demulsify water-in-oil (W/O) emulsions with high efficiency than that of respective EHANP.

Interfacial Activity of Bitumen Components

AbstractThe interfacial activity of asphaltenes, naphthenic acids, and naphthenates has been amply studied in the literature, as they are involved in the formation and stabilization of bitumen and heavy crude oil emulsions. While most of the literature evaluates one component at a time, in this work these bitumen components were separated one at a time from Athabasca bitumen, and the surface activity of the resulting fraction was evaluated as a function of pH, solvent aromaticity (heptane/toluene mixtures, known as heptol, at volume ratios 50/50 and 80/20), and temperature for selected systems. The interfacial activity was evaluated in two ways: via dynamic interfacial tension during adsorption on a bitumen drop of constant volume, and via dynamic interfacial tension during drop volume cycling. The adsorption data were interpreted using a model that combined multicomponent adsorption kinetics inspired by Langmuir–Freundlich kinetics with the Fainerman surface equation of state. The volume cycling experiments were interpreted using the compression relaxation model, which segregates adsorption/relaxation effects from elastic phenomena at interfaces. Overall, the adsorption data confirmed that naphthenic acids are the fastest adsorbing species that tend to dominate the interface, but that asphaltenes adsorb, almost irreversibly, at longer time scales and likely forming a sublayer previously proposed in the literature. The dilatational elasticity of the interface seems to be highly influenced by that asphaltene sublayer, which softens at high pH at room temperature, or at 80 °C independently of the pH of the system.