Emulsified Water Droplets Research Articles

Surface charge engineering for structural control of colloidal silica rod-decorated silica particles and their flexible integration into magnetic core–multishell structures

In this study, the effect of surface modification and the resulting surface charge of colloidal silica seeds on the growth of silica rods during an emulsion droplet-based process is investigated. Through electrostatic interactions between negatively charged poly(vinylpyrrolidone) (PVP) and seed surfaces, significant PVP adsorption occurs as the seed surfaces are modified with positively charged cationic substances and then aged with PVP. This surface charge-enhanced PVP adsorption promotes the anchoring of water emulsion droplets, serving as the starting point for the growth of silica rods on the seed surfaces and leading to a high yield of silica rod-decorated particles during emulsion droplet-based growth. The surface properties, including surface charge and hydrophobicity, can be further modified by applying different cationic modifiers, which influence the morphology, structural architecture, and yield of the final product. We further demonstrated the versatility of this approach by successfully generating silica rod-decorated magnetic core (Fe3O4)–multishell (silica/polystyrene/titania) particles. The findings of this study highlight the critical role of surface charge engineering in controlling the structure and morphology of silica rod-decorated silica particles as well as their integration into complex multicomponent systems.

Simulation of collision behaviour between droplet and solid surface in liquid phase environment

AbstractProcesses involving dispersed immiscible fluids occur across the traditional onshore and offshore crude oil development phases, including oil exploitation and production, gathering and transportation, and station and field processing. The stabilities of such processes are deeply influenced by the collision and film drainage between separated phase interfaces. Due to factors such as gravity as well as buoyancy and resistance, droplets usually collide with the wall at a relatively high speed and experience one or several rebounds before gradually stabilizing and staying on the surface. Though work related to this aspect has raised significant attention, further research on the force‐deformation behaviour between microsized (r ≈50 μm) droplets and solid surface under the influence of the above factors is still lacking and strongly demanded. In this paper, under the comprehensive influence of flow driving, an emulsified water droplet colliding with a solid surface in silicon oil is modelled. The dynamic behaviour of the droplet was analyzed by coupling the Stokes–Reynolds drainage equation, the generalized Young–Laplace equation, and the force situation of the deformable droplet. Furthermore, the effects of interfacial tension, collision velocity, and viscosity of continuous phase on the collision characteristics of droplet were analyzed, and it was found that these factors could significantly change the collision characteristics of droplet.

Aerogel-glass fiber composite filter media for effective separation of emulsified water droplets from diesel fuel

This work evaluates several mechanisms of separation of surfactant-stabilized emulsified water droplets from diesel fuel using high surface area (50–370 m2/g) and high porosity (>90 %) filter media fabricated by combining aerogels and glass fiber mats. Specifically, high surface area, porous gels of syndiotactic polystyrene (sPS) and silica are developed inside glass fiber mats via dip coating in corresponding sol followed by sol–gel transition. The resultant materials are supercritically dried to obtain aerogel-coated separation media. The abundant meso- and macropores of the aerogel network and the different surface energy of sPS and silica produce cooperative functioning of the mechanisms of size exclusion, coalescence filtration, surfactant adsorption, and volumetric water absorption for removal of emulsified water droplets from ultralow sulfur diesel fuel under continuous flow conditions. The role of each separation mechanism is elucidated in this paper. The results reveal high water separation efficiency of ∼92 % compared to ∼30 % for the glass fiber mats.

Water separation from diesel fuel using high surface area 3D-printed aerogel constructs

This work reports removal of emulsified water droplets from ultralow sulfur diesel (ULSD) fuel using high surface area aerogel filter media constructs. A synergistic combination of additive manufacturing and sol–gel chemistry is used for fabrication of the filter media constructs from high surface area (>200 m2/g) and high porosity (>90%) polyimide and syndiotactic polystyrene aerogels that are grown using sol–gel processes inside the load-bearing 3D-printed polymeric constructs of polyamide and high impact polystyrene respectively. This paper evaluates the roles of several factors on water separation efficiency, such as surface energy of polymer media on wetting, surfactant adsorption by the high surface area polymer media, and size exclusion of water droplets by smaller aerogel pores. The surfactant-stabilized water droplets in ULSD can be removed with a separation efficiency of up to 95% using these mechanically strong aerogel constructs.

Inkjet-based surface structuring: amplifying sweetness perception through additive manufacturing in foods

Additive manufacturing (AM) is creating new possibilities for innovative tailoring of food properties through multiscale structuring. This research investigated a high-speed inkjet-based technique aimed to modify sweetness perception by creating dot patterns on chocolate surfaces. The dots were formulated from cocoa butter with emulsified water droplets containing the sweetener thaumatin. The number and surface arrangement of dots, which ranged from uniformly distributed patterns to concentrated configurations at the sample’s center and periphery, were varied while maintaining a constant total amount of thaumatin per sample. A sensory panel evaluated sweetness perception at three consumption time points, reporting a significant increase when thaumatin was concentrated on the surface. Specifically, an amplification of sweetness perception by up to 300% was observed, irrespective of dot pattern or consumption time, when compared to samples where thaumatin was uniformly distributed throughout the bulk. However, when thaumatin was concentrated solely at the sample center, maximum sweetness perception decreased by 24%. Conclusively, both the proximity of thaumatin to taste receptors and its spatial distribution, governed by different dot arrangements, significantly influenced taste responsiveness. These findings present a more effective technique to substantially enhance sweetness perception compared to traditional manufacturing techniques. This method concurrently allows for sensorial and visual customization of products. The implications of this study are far-reaching, opening avenues for industrially relevant AM applications, and innovative approaches to study taste formation and perception during oral processing of foods.

The influence of water droplet packing on crude oil emulsion.

To assure a smooth and cost-efficient flow of crude oil emulsion from wells to a production facility, the oil industry relies heavily on the prediction of viscosity in pipe. The physical expression of this viscosity depends on a subjective estimate of a maximum packing volume fraction (compacity), ranging between 58 and 74 vol%. This inaccurate practice can lead to catastrophic loss of pump efficiency. Two new concepts were defined to describe the emulsion: its compacity; and the occupancy of water droplets at the oil-water interface. This development leads to a better understanding of the formation and disappearance of a suspension, and can assist in building a reliable phenomenological model of the sedimentation and coalescence of an emulsion. Theoretical and experimental approaches were conducted to investigate the packing of water droplets in emulsions. A 3D packing model was developed to explain the observations made during emulsification experiments. It was found that below a water volume fraction of 34 vol%, water droplets settle, under the effect of gravity, in a loose-packed zone; and then sediment in a dense-packed zone (DPZ). The DPZ exists between a water volume fraction of 34vol% and 60vol%. The maximum compacity is the upper limit of this zone; and has a value of 60.46%. Knowing this objective value, other parameters affecting the viscosity can be better studied.

Rheo-optic in situ synchronous study on the gelation behaviour and mechanism of waxy crude oil emulsions

An improved rheo-optic in situ synchronous measurement system was employed to investigate the gelation behaviour and mechanism of waxy crude oil emulsions. By combining transmitted natural light and reflected polarized light microscopy, a multiangle composite light source was built to achieve the simultaneous observation of wax crystals and emulsified water droplets, as well as their dynamic aggregation process. Main outcomes on the microscopic mechanism were obtained by developed microscopic image processing method. It was found that the microstructure of W/O waxy crude oil emulsion has the evolution of “individual structure--homogeneous aggregate structure--heterogeneous coaggregate structure--floc structure” during the static cooling, which results in the four stages during gelation process. Different from previous studies, the aggregation of emulsified water droplets was found to be more significant and contributes to the formation and development of the wax crystals-emulsified water droplets coaggregate, which plays a decisive role in the further evolution of the gelled microstructure. Time series microscopic images show the dynamic aggregation of emulsified water droplets and wax crystals. Two different aggregation behaviours between wax crystals and water droplets were observed. That wax crystals can not only embed in gaps between adjacent water droplets and enhance the structure, but also surround the outside of the water droplets and continue to grow resulting in the interconnection of different coaggregates to form a larger floc structure. In addition, correlation between viscoelasticity and microstructure evolution of waxy crude oil emulsions of different water contents was discussed. With increasing water contents, the microstructure is changed from wax crystal flocculation structure as the main skeleton and the emulsified water droplets embedded in it, into the aggregation of emulsified water droplets occupying the main position. When the number of wax crystals and water droplets reaches a certain ratio, did wax crystals form coaggregates with emulsified water droplets, and the remaining wax crystals formed an overall flocculation structure, the viscoelasticity of the waxy crude oil emulsion is the highest. • Dynamic aggregation of wax crystals and emulsified water droplets was observed. • Two different aggregation behaviours between wax crystals and water droplets were found. • Aggregation of water droplets was found to be significant for the microstructure evolution. • New microscopic mechanism for gelation of W/O Waxy Crude Oil Emulsion was presented. • Correlation between viscoelastic and microstructure evolution was discussed. • Different ratios between wax crystals and water droplets lead to different viscoelasticity.

Online Multiphase Flow Measurement of Crude Oil Properties Using Nuclear (Proton) Magnetic Resonance Automated Measurement Complex for Energy Safety at Smart Oil Deposits

The necessity of a flow express control of oil dispersed system (ODS) properties, such as crude oil, oil products, water–oil emulsions, and polluted waters, is substantiated. This control is necessary for the production and preparation of oil for transportation through the pipeline and oil refining, oil products, and wastewater treatment systems. A developed automatic measuring complex (AMC) is used to implement the concept of digital oil deposits. The primary measuring device is a relaxometer developed by us based on nuclear (proton) magnetic resonance (PMR). The design and operation algorithm of the AMC and the relaxometer are described. Equations have been developed to determine the ODS characteristics using the measured PMR parameters. This makes it possible to determine the flow rates of crude oil, the concentration of water in the oil, the concentration of asphaltene, resins, and paraffins in the oil, as well as the density, viscosity, and molecular weight of the oil. Additionally, it is possible to determine the dispersed distribution of water droplets in emulsions in oil production and treatment units. Data on this distribution will improve the management of separation processes. It has been established that the implemented control of multiphase ODS using PMR parameters (relaxation times, populations of proton phases, and amplitudes of spin-echo signals) makes it possible, using AMC, to assess the consumption of electricity in technological processes at the digital oil deposits, as well as during the transportation of oil and oil products through pipelines. AMC makes it possible to reduce electrical energy consumption in technological installations and reduce pollution emissions into wastewater. The advantages of using the developed AMC are shown in examples of its application. Such as an assessment of the influence of the gas factor on electricity consumption during oil transportation through pipelines or compensation for the additional moment of resistance on the shaft of the submersible motor, which is caused by surface tension forces at the interface of water droplets in the emulsion.

Effect of EVA wax inhibitor on the W/O emulsion stabilized by asphaltenes and paraffin wax

Ethylene-vinyl acetate copolymer (EVA) is a typical wax inhibitor. It is plausible the EVA could influence the stability of waxy crude oil emulsion because it was influencing both the dispersion state of asphaltenes and the wax precipitation properties. In this paper, the number after the EVA represents the VA content, and the more VA content means the stronger polarity of EVA. Based on the physical characteristics of model crude oil, the emulsion stability, and interfacial properties, the influence of EVA polarity (from EVA 10 to EVA 40) on the stability of model waxy crude oil emulsions (the oil/water volume ratio is fixed at 7:3) containing both asphaltenes and paraffin wax was systematically studied at two different temperatures (30 ℃ and 15 ℃). The results demonstrated that the increment of EVA polarity can not only greatly improve the dispersion state of asphaltenes, but also significantly improve the flowability of model crude oil by changing the morphology of wax crystals. The competitive adsorption of EVA to the interfacial film can be facilitated by the increased polarity of EVA, thus decreasing the asphaltene mass ratio in the interfacial film and then causing the decrease of the interfacial tension and the dilational modulus. The test temperature impacted the stability of the W/O emulsion. At the temperature of 30 ℃ which was higher than the wax appearance temperature (WAT), the interfacial modulus was the main factor affecting the emulsion stability and then increasing EVA polarity caused the emulsion stability to decrease. At the temperature of 15 ℃ below the WAT, due to the formation of large amount of wax crystal particles, the low-temperature flowability of the oil sample was greatly aggravated, which can improve the emulsion stability—increasing the EVA polarity greatly improved the oil rheology, thus leading to a decrease in the emulsion stability. In addition, the size of wax crystals formed in the emulsion was much smaller than those formed in the oil phase, but the amount became larger. We speculated that the emulsified water droplets could serve as wax nucleators, promoting the formation of wax crystal layers around the droplets, which will also favor the emulsion stability at 15 ℃.

Superhydrophobic copper foam bed with extended permeation channels for water-in-oil emulsion separation with high efficiency and flux

Developing separation materials with high separation efficiency and permeation flux for water-in-oil emulsions is an urgent demand and still a huge challenge. In this study, through anodization, electrostatic assembly of carbon nanotubes (CNTs), and grafting of nonafluorohexyltriethoxysilane (NFH-silane), a superhydrophobic copper foam containing re-entrant nanostructures was fabricated. The permeation channels were controllably extended by stacking multiple copper foams to form a columnar bed separator, and the residence time of emulsified water droplets was prolonged. When 30 pieces of copper foams were accumulated and the thickness of the stack was extended to 45 mm, the separation efficiency reached 99.14 %, and the permeation flux reached 31,500 Lm−2h−1 for separating surfactant-stabilized water-in-toluene emulsion. Due to the re-entrant nanostructures, the superhydrophobicity of the fabricated copper foam could keep stable in alkali, salt, oil environments, and only slightly decreased in surfactant environment, and the separation efficiency and flux can be recovered to the original level after multiple separation by simple cleaning, showing excellent superwettability stability and separation reusability. All these fascinating performance makes the superhydrophobic copper foam a promising candidate for continuous separating water-in-oil emulsions.

Magnetically recoverable poly (methyl methacrylate-acrylic acid)/iron oxide magnetic composites nanomaterials with hydrophilic wettability for efficient oil-water separation

Due to the environmental and production problems of emulsion, it is important to efficiently separate oil-water emulsion to meet the refinery requirement and clean up oil spills. Synthesis of a universal demulsifier is not an easy task because the physical properties of crude oil vary, which makes its characterization and demulsification procedure difficult. To overcome this problem, hydrophilic and magnetically recoverable poly (methyl methacrylate-acrylic acid)/iron oxide magnetic composite nanoparticles ((P(MMA-AA)/Fe3O4 NPs) were developed as an efficient and economical demulsifier via soap-free emulsion polymerization. To characterize the magnetic composite NPs for their appropriate surface morphology and magnetic domain, TEM, FTIR, VSM, and TGA analyses were carried out. The newly synthesized NPs displayed good hydrophilic properties as they migrated quickly to the aqueous emulsion phase, which was also reassured by their water contact angle of 75°. They exhibit strong magnetic characteristics (20 amu/g) in the oil-water emulsion, makings the hydrophilic wettability capable and attractive to the external magnet. Experimental results revealed that the prepared magnetic composite NPs separated 99% of the water from stable emulsion in 30 min and could be recycled 8 times through magnetic separation. The recycled magnetic composite NPs maintain their hydrophilic wettability and efficiency in separating oil-water emulsion, making them economical and commercially viable. The migration of magnetic composite NPs to the aqueous phase in the stable emulsion with a strong magnetic domain explains the coalescence of emulsified water droplets and their quick separation from the stable emulsions through the external magnet.

Coalescence behavior of water droplets in emulsions

Coalescence behavior of water droplets in emulsions

The impact of SiO2 nanoparticles on the dilational viscoelastic properties of water-nonionic surfactant-fuel interface

Surfactants in ultra-low sulfur diesel (ULSD) can improve the stability of the emulsified water droplet by forming a thin film at the water-fuel interface. Emulsified water droplets block the oil spray nozzle and break down the engine, which need to be removed. For colliding emulsified water droplets, surfactant film with high viscoelastic modulus provides an obstacle to their coalescence. Micro/nanosized-SiO2 particles were added into ULSD to interrupt the arrangement of the surfactant film. After adding with 20 nm SiO2, the interfacial tension of water-monoolein-ULSD increased from 16.0 mN/m to 21.4 mN/m, and its viscoelastic modulus decreased from 17.1 mN/m to 10.9 mN/m, a decrease of 36.3%. It proved that the addition of nanosized SiO2 into water-monoolein-ULSD system increased the interfacial tension and reduced the viscoelastic modulus of the monoolein film. However, after adding nanosized SiO2, the viscoelastic modulus of the water-PETO-B-ULSD layer had no significant changes. Therefore, we concluded that 20 nm SiO2 disturbed the dense packing of monoolein as its adsorption to surfactants and the electrostatic repulsion force between them and the hydrophobic group, resulting in a decrease in elastic modulus. However, PETO-B had a complex branched structure leading to a loose packing, which had unoccupied adsorption sites and barely affected by the intrusion of 20 nm SiO2. Therefore, this research provided a strategy to add nanosized-SiO2 into W/O emulsions containing monoolein-like surfactant to reduce its stability.

Revealing the mechanism of superwetting fibrous membranes for separating surfactant-free water-in-oil emulsions

Although massive superwetting fibrous membranes have been developed for separating water-in-oil emulsions, the optimization of their separation performance is still a challenge due to their unclear separation mechanism. Herein, two kinds of superwetting fibrous membranes were designed for separating surfactant-free water-in-oil emulsion and their separation mechanism was thoroughly revealed. Firstly, the underoil superhydrophilic fibrous membrane and the underoil superhydrophobic fibrous membrane were fabricated, then their separation performance was evaluated. Furthermore, the coalescence process of emulsified water droplets on and within the fibrous membrane was directly observed by the dye-tracking experiment and the coalescence dynamics of emulsified droplets were further investigated via the phase-field simulation method. Finally, a model for understanding the separation mechanism of superwetting fibrous membrane for surfactant-free water-in-oil emulsion was proposed. Additionally, the designed fibrous membrane exhibited an ultrafast emulsion permeation flux up to 50,000 L/m2h with high separation efficiency of >99.6% under a negative pressure, demonstrating a great industrial application potential for the treatment of water-in-oil emulsion.

Flexible capacitive pressure sensors with micro-patterned porous dielectric layer for wearable electronics

Highly sensitive soft sensors play key roles in flexible electronics, which therefore have attracted much attention in recent years. Herein, we report a flexible capacitive pressure sensor with high sensitivity by using engineered micro-patterned porous polydimethylsiloxane (PDMS) dielectric layer through an environmental-friendly fabrication procedure. The porous structure is formed by evaporation of emulsified water droplets during PDMS curing process, while the micro-patterned structure is obtained via molding on sandpaper. Impressively, this structure renders the capacitive sensor with a high sensitivity up to 143.5 MPa−1 at the pressure range of 0.068 ∼ 150 kPa and excellent anti-fatigue performance over 20 000 cycles. Meanwhile, the sensor can distinguish different motions of the same person or different people doing the same action. Our work illustrates the promising application prospects of this flexible pressure sensor for the security field or human motion monitoring area.

High-efficiency and durable removal of water-in-heavy oil emulsions enabled by delignified and carboxylated basswood with zwitterionic nanohydrogel coatings

HypothesisIt is hypothesized that grafting zwitterionic nanohydrogel (ZNG) helps to achieve anti-asphaltene properties on cellulosic substrates, thus overcoming the fouling issue of natural cellulosic materials for treating oily emulsions. It is also hypothesized that ZNG coatings enhance the water-binding affinity of the substrates, resulting in an outstanding water-removal performance on asphaltene-stabilized emulsions with long-term stability. ExperimentsA cellulosic substrate was derived from nature basswood via a sequence of delignification and carboxylation processes. The ZNG-DBS composite was then developed by esterification to covalently graft ZNGs on the inner channels of the substrate. The water-binding affinity, wettability, water-removal performance for treating water in asphaltene-stabilized emulsions were evaluated via characterizing the filtration/absorption, and anti-fouling mechanism of the ZNG-DBS. FindingsZNG coatings enhance the hydration capability of the basswood substrate, allowing it to absorb water emulsion droplets protected by asphaltenes in the oil medium without being contaminated. Moreover, superior and stable removal capabilities were achieved by using this unique material to treat asphaltenes-stabilized water-in-oil emulsions with the water residue content of <1.0 and ∼0.065 wt% via cyclic filtration and absorption tests, respectively. Our results demonstrate the successful conversion of widely accessible wood resources to functional materials with great potential in the practical treatment of oily wastewater.

Demulsification of saline-in-crude oil via biocompatible cellulose derivative polymers

Water-in-crude oil emulsions cause corrosion in upstream and catalyst deactivation in downstream oil processing. It is essential to demulsify and remove aqueous impurities from oil in production facilities. In this study carboxymethyl cellulose (Walocel), cellulose acetate, and two methyl cellulose with different methyl and 2-hydroxypropyl derivative contents (Methocel-K3 and Methocel-E5) are used as biocompatible polymeric water-in-crude oil demulsifiers. Screening bottle tests revealed that Walocel and Methocel-E5 are more suitable for deionized water-in-crude oil demulsification. Better performance of Methocel-E5 compared to that of Methocel-K3 is due to comparative abundance of methyl substitutes in Methocel-E5 which assist interaction with oil. Further demulsification experiments at different temperatures and demulsifier concentrations confirmed that Walocel is comparatively more effective than Methocel-E5 for deionized water- and saline-in-crude oil demulsification. An increase in temperature/demulsifier concentration favor demulsification via increasing the number of effective collisions between emulsified water droplets which destabilize the emulsion. Presence of ions slows down the demulsification of Methocel E5 more than that of Walocel. Better performance of Walocel is probably due to the abundance and strength of its directional hydrogen bonds as well as electrostatic and van der Waals interactions with water via its charged carboxy groups which are less affected by ion content of saline; thus, relatively retain their ability to weaken asphaltene- and resins-assisted water interaction with crude oil. The polar 2-hydroxypropyl substitutes in Methocel E5 provides comparatively reduced number/strength of hydrogen bonds as well as relatively weak van der Waals interactions with water molecules which are more severely affected by shielding impact of ions resulting in much less effective saline demulsification with Methocel E5.

Asphaltene instability in the presence of emulsified aqueous phase

Water cut of high salinity, which is reported to be on the rise in many reservoirs, may profoundly exacerbate asphaltene related problems. In this work, the impact of the emulsified aqueous phase in synthetic oils on asphaltene precipitation has experimentally been studied. The oil phase of each emulsion was divided into three sub-fractions of oils 1, 2, and 3, based on their asphaltene’s affinity to interact with the oil/water interface. These three sub-fractions were then contacted with n-heptane as precipitator. The influence of ion types, temperature, and finally the presence of tetrahydrofuran (THF) in emulsified aqueous phases were further investigated for two different asphaltene samples. Moreover, the role of ions on asphaltene interaction with the oil/water was examined using interfacial tension, interfacial rheology, and droplet size analysis. The results showed that precipitation behavior of oils 1, 2, and 3 would be controlled by changes in relative distribution of asphaltene sub-fractions and their respective concentration. IFT measurements showed that asphaltenes in oils 1, 2, and 3 have different interactions with de-ionized water. Ions of higher valence, like Fe3+, also would profoundly decrease the size of water droplets in emulsion and also cause more asphaltene to remain in emulsions. When THF was added to the injected aqueous phase, then it got partitioned between aqueous and oleic phases. Thus, its addition to the emulsified aqueous phase firstly stemmed emulsion formation, and secondly, it alleviated asphaltene precipitation by diluting the oil phase at the oil/water interface. IFT measurements showed that asphaltenes in oils 1, 2, and 3 had different interactions with the de-ionized water. It was shown that brines did not directly affect the asphaltene precipitation. Instead, their presence had a noticeable impact on the distribution of asphaltene between the bulk of the oil and emulsion phases. This, in turn, altered the precipitation of asphaltene of the oil. The findings of this study address the main concerns about asphaltene destabilization by aqueous phase injection to petroleum reservoirs.

Digital droplet PCR as a predictive tool for successful discontinuation outcome in chronic myeloid leukemia: Is it time to introduce it in the clinical practice?

Tyrosine kinase inhibitors (TKIs) have drastically changed the outcome of chronic myeloid leukemia (CML) patients. A sustained and deep molecular response achieved over time paves the way to therapy discontinuation, and is a pre-requisite to attempt treatment-free remission. Monitoring of the molecular response during treatment discontinuation is routinely carried out by RQ-PCR, but it may not be the optimal tool to monitor minimal residual disease at the time of stopping treatment and during treatment discontinuation. Different digital PCR platforms (such as droplet dPCR) are available, a method based on water-emulsion droplet technology in which the sample is partitioned into 20,000 droplets and PCR amplification of the template subsequently occurs in each individual droplet. The consequent high sensitivity and precision with a very reliable quantification without the need of a calibration curve and the exquisite reproducibility makes this procedure as an ideal alternative method for the detection of very low levels of disease. Aim of this review is to describe and discuss the recent use of dPCR/ddPCR in CML, focusing in particular on its role in TKI treatment discontinuation strategies.

Cellulose-coated magnetic Janus nanoparticles for dewatering of crude oil emulsions

Removing process water from crude oil emulsions is critically required prior to their downstream processing. In this work, cellulose-coated magnetic Janus nanoparticles (MJ NPs) of asymmetric surface wettability were applied to dewatering crude oil emulsions under an applied magnetic field. Despite the emulsified water droplets stabilized by asphaltene film, the MJ NPs showed stronger interfacial activities, making more secure deposition at the interface as compared with interfacially active magnetic nanoparticles (IM NPs) of uniform surface modification. The MJ NPs could remove >90% water from the emulsions of different water contents, showing their robust dewatering ability. The spent MJ NPs were regenerated via standard washing, drying and resuspension process, and reused for at least six cycles while retaining excellent interfacial activities and high dewatering efficiency. Due to the coating of environmentally benign and biodegradable celluloses, the MJ NPs could achieve excellent dewatering without generating secondary hazards to the crude oil.