Advances in ultrasonic treatment of oily sludge: mechanisms, industrial applications, and integration with combined treatment technologies.

In the petroleum sector, the generation of oily sludge is an unavoidable byproduct, necessitating the development of efficient treatment strategies for both economic gain and the mitigation of negative environmental impacts. The intricate composition of oily sludge poses a formidable challenge, as existing treatment methodologies frequently fall short of achieving baseline disposal criteria. The processes of demulsification and dehydration are integral to diminishing the oil content and reclaiming valuable crude oil, thereby playing a critical role in the management of oily sludge. Among the myriad of treatment solutions, ultrasonic technology has emerged as a particularly effective physical method, celebrated for its diverse applications and lack of resultant secondary pollution. This comprehensive review delves into the underlying mechanisms and recent progress in the ultrasonic treatment of oily sludge, with a specific focus on its industrial implementations within China. Both isolated ultrasonic treatment and its combination with other technological approaches have proven successful in addressing oily sludge challenges. The adoption of industrial-scale systems that amalgamate ultrasound with multi-technological processes has shown marked enhancements in treatment efficacy. The fusion of ultrasonic technology with other cutting-edge methods holds considerable potential across a spectrum of applications. To fulfill the goals of resource recovery, reduction, and neutralization in oily sludge management, the industrial adoption and adept application of a variety of treatment technologies are imperative.

Synthesis and application of recyclable magnetic cellulose nanocrystals for effective demulsification of water in crude oil emulsions.

The development of eco-friendly, efficient, and economical demulsifiers for the demulsification of water in crude oil emulsion is one of the important issues in the petroleum industry. Demulsifiers with suitable performance in several demulsification methods are good choices for effective and economical demulsification. In this study, recyclable magnetic cellulose nanocrystals have been synthesized from cotton by a simple method and used in the demulsification of water in crude oil emulsions. Chemical and magnetic demulsification by magnetic cellulose nanocrystals has been investigated. In addition, the effects of time, temperature, and demulsifier concentration on the demulsification efficiency have been evaluated. According to the results, this demulsifier can be used as an effective demulsifier for both chemical and magnetic demulsification and displayed a demulsification efficiency of 100 % at 50 °C without a magnet and 90 % at 20 °C with a magnet. The chemical demulsification efficiency of Fe3O4 nanoparticles was investigated and it showed lower DE compared to magnetic cellulose nanocrystals. The recyclability tests of the demulsifier indicated that magnetic cellulose nanocrystals can be used up to 4 times. Finally, the demulsification mechanism and interfacial tension measurements revealed that this demulsifier reduced the interfacial tension between water and crude oil and increased the water droplet sizes.

Determination of chiral prothioconazole and its chiral metabolite in water, juice, tea, and vinegar using emulsive liquid-liquid microextraction combined with ultra-high performance liquid chromatography.

Emulsive liquid-liquid microextraction (ELLME), a simple, rapid, and environmentally friendly technique, was established to identify chiral prothioconazole and its chiral metabolite in water, juice, tea, and vinegar using ultra-high-performance liquid chromatography (UPLC). Environmentally friendly extractant was mixed with pure water to prepare a high-concentration emulsion, which was added to samples to complete the emulsification and extraction in 1 s. Afterward, an electrolyte solution was added to complete the demulsification without centrifugation. ELLME did not use dispersants compared to the familiar dispersive liquid-liquid microextraction (DLLME), thus reducing the use of toxic solvents and avoiding the effect of dispersants on the partition coefficient. The linear range was from 0.01 to 1 mg/L. The limit of detection was 0.003 mg/L. The extraction recoveries ranged from 82.4 % to 101.6 %, with relative standard deviations of 0.7-5.2 %. The ELLME method developed has the potential to serve as an alternative to DLLME.

In-depth potential mechanism of combined demulsification pretreatments (isopropanol ultrasonic pretreatments and Ca2+ flow additions) during aqueous enzymatic extractions of Camellia oils.

Emulsification is the practical limitation of aqueous enzymatic extractions of Camellia oils. This study aimed to investigate the influence and demulsification mechanisms of isopropanol ultrasonic pretreatments and Ca2+ additions on aqueous enzymatic extractions of Camellia oils. Combining isopropanol ultrasonic pretreatments with Ca2+ flow additions obtained the highest free oil recovery (78.03 %) and lowest emulsion content (1.5 %). Results indicated that the superior demulsification performance originated from the decrease in emulsion stabilities and formations. First, demulsification pretreatments reduced the oil (14.69 %) and solid (13.21 %) fractions in emulsions to decrease the stability of as-formed emulsions. Meanwhile, isopropanol ultrasonic pretreatments extracted tea saponins (0.38 mg/mL) and polysaccharides (0.23 mg/mL), while Ca2+ combined with protein isolates (5.82 mg/mL), tea saponins (7.48 mg/mL) and polysaccharides (0.78 mg/mL) to form precipitates and reduce emulsion formation. This work could promote the practical application of aqueous enzymatic extractions of Camellia oils and enlighten the rise of advanced demulsification pretreatments.

Demulsification of amphiphilic gemini ionic liquids and its demulsification mechanism.

This work aims to prepare two new amphiphilic and interfacial active gemini ionic liquids to treat crude oil and investigates its demulsification mechanism. Tetraethylene glycol was pretreated with thionyl chloride and used as a linker to connect succinimide or phthalimide, and then reacted with dodecyl benzene sulphonic acid to obtain the corresponding amphiphilic and interfacial active gemini ionic liquid STA or PTA, respectively. 1H nuclear magnetic resonance spectroscopy (1HNMR) and Fourier-transform infrared spectroscopy (FTIR) was used to determine the chemical structures. The demulsification tests showed the demulsification efficiency with 150 mg/L of STA or PTA at 60 °C for 30 min was 99.89% and 99.79%, respectively. Furthermore, the demulsification mechanism of STA and PTA were studied and the prominent demulsification ability of STA and PTA were attributed to the better interfacial activity and amphipathy which could destroy the asphaltenes interfacial film. These results showed that STA and PTA had excellent demulsification efficiency, which promised application in petroleum industry.

Rapid tissue prototyping with micro-organospheres.

In vitro tissue models hold great promise for modeling diseases and drug responses. Here, we used emulsion microfluidics to form micro-organospheres (MOSs), which are droplet-encapsulated miniature three-dimensional (3D) tissue models that can be established rapidly from patient tissues or cells. MOSs retain key biological features and responses to chemo-, targeted, and radiation therapies compared with organoids. The small size and large surface-to-volume ratio of MOSs enable various applications including quantitative assessment of nutrient dependence, pathogen-host interaction for anti-viral drug screening, and a rapid potency assay for chimeric antigen receptor (CAR)-T therapy. An automated MOS imaging pipeline combined with machine learning overcomes plating variation, distinguishes tumorspheres from stroma, differentiates cytostatic versus cytotoxic drug effects, and captures resistant clones and heterogeneity in drug response. This pipeline is capable of robust assessments of drug response at individual-tumorsphere resolution and provides a rapid and high-throughput therapeutic profiling platform for precision medicine.

Molecular dynamics simulation on water/oil interface with model asphaltene subjected to electric field.

HYPOTHESIS: The droplet-medium interfaces of petroleum emulsions are often stabilized by the indigenous surface-active compounds (e.g., asphaltenes), causing undesired issues. While demulsification by electric field is a promising technique, fundamental study on the droplet-medium interface influenced by electric field is limited. Molecular dynamics (MD) simulations are expected to provide microscopic insights into the nano-scaled water/oil interface. METHODS: MD simulations are conducted to study the adsorption of model asphaltene molecules (represented by N-(1-hexylheptyl)-N'-(5-carboxylicpentyl) perylene-3,4,9,10-tetracarboxylic bisimide (C5Pe)) on a water-toluene interface under various strengths of electric field. The adsorption amount and structural feature of C5Pe molecules at water-toluene interface are investigated, and the effects of electric field and salt are discussed. FINDINGS: C5Pe molecules tend to adsorb on the water-oil interface. As the electric field strength increases, the adsorption amount first slightly increases (or remains constant) and then decreases. The electric field disrupts the compact π-π stacking between C5Pe molecules and increases their mobility, causing a dispersed distribution of the molecules with a wide range of orientations relative to the interface. Within the studied range, the addition of salt ions appears to stabilize the interface at high electric field. These results provide useful insights into the mechanism and feasibility of demulsification under electric field.

Efficient Separation and Recovery of Petroleum Hydrocarbon from Oily Sludge by a Combination of Adsorption and Demulsification.

The treatment of oily sludge (OS) can not only effectively solve environmental pollution but also contribute to the efficient use of energy. In this study, the separation effect of OS was analyzed through sodium lignosulfonate (SL)-assisted sodium persulfate (S/D) treatment. The effects of SL concentration, pH, temperature, solid-liquid ratio, revolving speed, and time on SL adsorption solubilization were analyzed. The effects of sodium persulfate dosage, demulsification temperature, and demulsification time on sodium persulfate oxidative demulsification were analyzed. The oil removal efficiency was as high as 91.28%. The results showed that the sediment was uniformly and finely distributed in the S/D-treated OS. The contact angle of the sediment surface was 40°, and the initial apparent viscosity of the OS was 56 Pa·s. First, the saturated hydrocarbons and aromatic hydrocarbons on the sediment surface were adsorbed by the monolayer adsorption on SL. Stubborn, cohesive oil agglomerates were dissociated. Sulfate radical anion (SO4-·) with a high oxidation potential, was formed from sodium persulfate. The oxidation reaction occurred between SO4-· and polycyclic aromatic hydrocarbons. A good three-phase separation effect was attained. The oil recovery reached 89.65%. This provides theoretical support for the efficient clean separation of oily sludge.

New Amphiphilic Ionic Liquids for the Demulsification of Water-in-Heavy Crude Oil Emulsion.

This work aimed to use abietic acid (AA), as a widely available natural product, as a precursor for the synthesis of two new amphiphilic ionic liquids (AILs) and apply them as effective demulsifiers for water-in-crude oil (W/O) emulsions. AA was esterified using tetraethylene glycol (TEG) in the presence of p-toluene sulfonic acid (PTSA) as a catalyst obtaining the corresponding ester (AATG). AATG was reacted with 1-vinylimidazole (VIM) throughout the Diels-Alder reaction, forming the corresponding adduct (ATI). Following this, ATI was quaternized using alkyl iodides, ethyl iodide (EI), and hexyl iodide (HI) to obtain the corresponding AILs, ATEI-IL, and ATHI-IL, respectively. The chemical structure, surface activity, thermal stability, and relative solubility number (RSN) were investigated using different techniques. The efficiency of ATEI-IL and ATHI-IL to demulsify W/O emulsions in different crude oil: brine volumetric ratios were evaluated. ATEI-IL and ATHI-IL achieved promising results as demulsifiers. Their demulsification efficiency increased as the brine ratios decreased where their efficiency reached 100% at the crude oil: brine ratio (90:10), even at low concentrations.

Demulsification of Heavy Oil-in-Water Emulsion by a Novel Janus Graphene Oxide Nanosheet: Experiments and Molecular Dynamic Simulations.

Various nanoparticles have been applied as chemical demulsifiers to separate the crude-oil-in-water emulsion in the petroleum industry, including graphene oxide (GO). In this study, the Janus amphiphilic graphene oxide (JGO) was prepared by asymmetrical chemical modification on one side of the GO surface with n-octylamine. The JGO structure was verified by Fourier-transform infrared spectra (FTIR), transmission electron microscopy (TEM), and contact angle measurements. Compared with GO, JGO showed a superior ability to break the heavy oil-in-water emulsion with a demulsification efficiency reaching up to 98.25% at the optimal concentration (40 mg/L). The effects of pH and temperature on the JGO's demulsification efficiency were also investigated. Based on the results of interfacial dilatational rheology measurement and molecular dynamic simulation, it was speculated that the intensive interaction between JGO and asphaltenes should be responsible for the excellent demulsification performance of JGO. This work not only provided a potential high-performance demulsifier for the separation of crude-oil-in-water emulsion, but also proposed novel insights to the mechanism of GO-based demulsifiers.

Screening and Demulsification Mechanism of Fluorinated Demulsifier Based on Molecular Dynamics Simulation.

In order to solve the problem of demulsification difficulties in Liaohe Oilfield, 24 kinds of demulsifiers were screened by using the interface generation energy (IFE) module in the molecular dynamics simulation software Materials Studio to determine the ability of demulsifier molecules to reduce the total energy of the oil-water interface after entering the oil-water interface. Neural network analysis (NNA) and genetic function approximation (GFA) were used as technical means to predict the demulsification effect of the Liaohe crude oil demulsifier. The simulation results show that the SDJ9927 demulsifier with ethylene oxide (EO) and propylene oxide (PO) values of 21 (EO) and 44 (PO) reduced the total energy and interfacial tension of the oil-water interface to the greatest extent, and the interfacial formation energy reached -640.48 Kcal/mol. NNA predicted that the water removal amount of the SDJ9927 demulsifier was 7.21 mL, with an overall error of less than 1.83. GFA predicted that the water removal amount of the SDJ9927 demulsifier was 7.41mL, with an overall error of less than 0.9. The predicted results are consistent with the experimental screening results. SDJ9927 had the highest water removal rate and the best demulsification effect. NNA and GFA had high correlation coefficients, and their R2s were 0.802 and 0.861, respectively. The higher R2 was, the more accurate the prediction accuracy was. Finally, the demulsification mechanism of the interfacial film breaking due to the collision of fluorinated polyether demulsifiers was studied. It was found that the carbon-fluorine chain had high surface activity and high stability, which could protect the carbon-carbon bond in the demulsifier molecules to ensure that there was no re-emulsion due to the stirring external force.

Emulsification/demulsification method coupled to GC-MS/MS for analysis of multiclass pesticide residues in edible oils.

A simple, rapid, and sensitive method was developed for simultaneous determination of 103 multiclass pesticides in edible oils. A new strategy of sample preparation involving a spontaneous emulsification followed by membrane-based demulsification was proposed. The developed strategy was compared with other reputed clean-up procedures and found to improve the removal efficiency of matrix interferences without a significant loss of pesticides. GC-MS/MS was used to evaluate the proposed treatment methodologies. Recovery studies were performed at 10, 20, and 50 µg/kg levels in soybean oil, olive oil, and rapeseed oil. Throughout the validations, 70-120% overall recoveries were achieved with RSDs < 10% for the majority of pesticides. Limits of quantification ranged from 10 to 50 µg/kg (10 µg/kg for over 92% pesticides), less than the regulatory MRLs. Twenty-two of 30 market samples were found to contain one or several detectable pesticide residues ranged from < 1 to 105.9 µg/kg.

Demulsification of water-in-crude oil emulsion driven by a carbonaceous demulsifier from natural rice husks.

Removing emulsified water from a water-in-crude oil (W/O) emulsion is critically required prior to downstream processing in the petroleum industry. In this work, environmentally friendly and amphipathic rice husk carbon (RHC) demulsifier was prepared by a simple carbonization process in a muffle furnace using rice husks as starting materials. RHC was characterized by field-emission scanning electron microscope, energy dispersive spectrometer, Fourier transform infrared spectrometer, ultraviolet-visible spectrometer, powder X-ray diffraction, zeta potential and synchronal thermal analyzer. The factors such as dosage, temperature, settling time, pH value and salinity were systematically investigated. The results indicated that the dehydration efficiency (DE) reached as high as 96.99% with 600 mg/L of RHC for 80 min at 70 °C. RHC exhibited an optimal DE under neutral condition, but it was also effective under acidic and alkaline conditions. Also, it had an excellent salt tolerance. The possible demulsification mechanism was explored by interfacial properties, different treatment methods for RHC and microexamination. The demulsification of RHC is attributed to its high interfacial activity, oxygen-containing groups and content of silica. It indicates that RHC is an effective demulsifier for the treatment of the W/O emulsion.

Treatment of oil-based drilling cuttings using the demulsification separation-Fenton oxidation method.

In this study, demulsification separation-Fenton oxidation technology was employed as a combined technology to treat total petroleum hydrocarbons (TPH) in oil-based drill cuttings (OBDC). Batch experiments were carried out to optimize the technology parameter. Under the optimal condition, 70% and 51% TPH removal rate was obtained for demulsification technology and Fenton oxidation technology, respectively. Eighty-five percent of TPH removal rate was obtained using combination technology of demulsification separation and Fenton oxidation. Multiple characterizations were used to analyze the physical and chemical properties of treated OBDC. The result of XRD pattern indicated the combination technology had no obvious effect for structure phase of OBDC. The results of FTIR, GC-MS, TG-DTG and SEM were used to characterize the treated OBDC. This paper provides an efficient and feasible combined technology for OBDC treatment, which expands a new strategy for the removal of TPH from solid waste.

Effective remediation of petrochemical originated pollutants using engineered materials with multifunctional entities.

The highly robust, effective, and sustainable remediation of hydrocarbon-contaminated wastewater matrices, which is mainly generated from petroleum and related petrochemical industries, is of supreme interest. Owing to the notable presence of suspended solids, oil, and grease, organic matter, highly toxic elements, high salts, and recalcitrant chemicals, crude oil emulsions, and hydrocarbon-contaminated wastewater are considered a potential threat to the environments, animals, plants, and humans. To effectively tackle this challenging issue, magnetic hybrid materials assembled at nano- and micro-scale with unique structural, chemical, and functional entities are considered robust candidates for demulsification purposes. The current research era on magnetic materials has superwettability, leading to an effective system of superwettability, which is vibrant and promising. The wettability of magnetic and magnetic hybrid materials explaining the theme of superhydrophobicity and superhydrophilicity under the liquid. Herein, we reviewed the applications of magnetic nanoparticles (MNPs) as effective demulsifiers. The demulsifier wettability, dose, pH, salinity, and surface morphology of compelling, magnetic nanoparticles are the main hidden factors in effective demulsifiers. There is a comprehensive discussion on the reuse and recyclability of MNPs after oil, water separation. Furthermore, the main challenges, coupled with the magnetic nanoparticles in the effective separation of emulsions, are intensified in detail. This review will compare the current literature and the utilization of MNPs for the demulsification of oil and water emulsions. This is envisioned that the MNPs would be critical in the petroleum and petrochemical industry to effectively eliminate water from a crude oil emulsion.

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.

Fate of phospholipids during aqueous extraction processing of peanut and effect of demulsification treatments on oil-phosphorus-content.

PC (phosphatidylcholine), PE (phosphatidylethanolamine), PI (phosphatidylinositol), and PA (phosphatidic acid) in 9 peanut matrices obtained during the AEP (aqueous extraction processing) of peanut were quantified employing HPLC-ELSD analysis in this study. Phosphorus contents of crude oils obtained from different demulsification treatments were also investigated. Decantation had a larger effect than grinding in terms of phospholipids loss due to alkaline-hydrolysis, indicating this processing step was vital for the manipulation of phospholipids levels remained in oil. Over 80% of initial phospholipids were lost during AEP and only 19.8% of initial phospholipids ended up in cream, skim and sediment phase. 52.55% of the remained phospholipids trapped in cream phase. Just 22.16-32.61 mg/kg phosphorus content could be detected in crude oils, which indicated the separation of phospholipids from the cream phase into aqueous medium. Degumming was not essential in AEP of peanut and the waste generated after demulsification could be a source of phospholipids.

MPEG grafted alkylated carboxymethyl chitosan as a high-efficiency demulsifier for O/W crude oil emulsions.

Three kinds of novel environmentally benign and high-efficiency crude oil demulsifiers were prepared using methoxy polyethylene glycol (MPEG) to modify alkylated carboxymethyl chitosan (ACMC). Structures of the demulsifiers were confirmed using FT-IR and 1H NMR, and the relationship between surface tension and concentration was tested. Demulsification performance was investigated using the bottle test method with oil-in-water (O/W) emulsions that were prepared in lab conditions. The demulsification efficiency was as high as 79.1 %-84.9 %, and the possible mechanism of the demulsification process is discussed. Results show that MPEG-grafted ACMC (MPEG-ACMC) has a promising application as a demulsifier for dealing with emulsified O/W crude oil.

Application of biosurfactant surfactin as a pH-switchable biodemulsifier for efficient oil recovery from waste crude oil.

Efficient oil separation is the most desirable, but still challenging solution for the waste crude oil problem. This study developed biosurfactant surfactin as a novel pH-switchable biodemulsifier for efficient oil separation. As found, surfactin demulsification achieved a quite well oil separation ratio of over 95% on model emulsions after 20 min at 50 °C. The validity of this demulsification process should be mainly based on the readily lost stabilization ability of surfactin in emulsions triggered by acid addition. Then, surfactin (0.2 g/L) treatment with the aid of ethanol (2%) to improve its distribution could recover over 95% of oil from waste crude oil. After treated by surfactin, the separated oil phase contains tiny water (less than 0.5%) and thus can be reused for resource recycling to reach a compromised balance between satisfying the strict environmental regulations and decreasing the high treatment costs. Hence, in consideration of high demulsification efficiency, environmental-friendly properties and cost-efficiency, surfactin has a great potential for industrial applications for oil recovery from waste crude oil which is a severe problem presents in most of the petroleum-related factories.

Combined heating and chemical treatment for oil recovery from aging crude oil.

With increasing use of chemical oil displacement agents in tertiary recovery and the application of various demulsifiers for crude oil dehydration, a large amount of aging crude oil containing a high ratio of water is produced, and it is very difficult for processing and utilisation. In this article, we chose aging crude oil samples from a union station in an oilfield in China. Sample composition was analysed to demonstrate that the key of aging crude oil dehydration is the removal of solid impurities. Thus, an efficient method of combining heating and chemical treatments was developed to treat aging crude oil. It includes two steps: The first step is washing of aging crude oil with hot water with sodium dodecylbenzene sulfonate; the second step is chemical demulsification of the above mixture with hydrochloric acid and sodium chloride solution. The result showed that 2.9% of solid impurities and 29.2% of water were removed in the first step; 27.2% of oil, 24.3% of water, and 3.47% of solid impurities in the aging crude oil were recycled in the second step. A total 87.07% of aging crude oil could be solved with this method. The present two-step treatment method can ensure that the dehydration process runs normally and efficiently in the union station, making it a promising method in the recycling of aging crude oil.