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In this work, robust superhydrophobic cotton fabrics with UV shielding, self-cleaning, photocatalysis, and oil/water separation were successfully prepared based on micro/nano hierarchical ZnO/HNTs (halloysite nanotubes) hybrid particles and silicone elastomer polydimethylsiloxane (PDMS). ZnO/HNTs hybrid particles were prepared by in-situ growth of ZnO nanoparticles on the surface of halloysite nanotubes (HNTs). ZnO/HNTs hybrid particles and PDMS were used to successively coat cotton fabric by dip-coating approach. The coated cotton fabric displayed excellent superhydrophobicity with a water contact angle of 162.5 ± 1° and photocatalytic degradation of methylene blue solution under UV irradiation owing to the roughness and photocatalytic performance provided by micro/nano hierarchical ZnO/HNTs hybrid particles and low surface energy achieved by PDMS. The as-prepared fabric also displayed outstanding self-cleaning and antifouling properties. In addition, due to its both superhydrophobic and superoleophilic characteristics, the as-prepared cotton fabric can be used to separate several oil/water mixtures and showed good recoverability. The superhydrophobic cotton fabric also exhibited excellent UV shielding performance with a large UV protection factor of 1643.28 due to strong ultraviolet-absorption, light scattering and frequent light reflection of ZnO nanoparticles in ZnO/HNTs composites coated on cotton fabric. Importantly, the as-prepared fabric retained superhydrophobic performance after 2000 cycles rubbing, 90h UV illumination, and immersing in acidic and alkali solutions with different pH values ranging from 1 to 14 for 1 h. These characteristics make multifunctional cotton fabrics a satisfactory candidate in various promising fields.

In view of the classical Lucas-Washburn equation, which can only describe the spontaneous imbibition of single wetted capillary, a tilted composite capillary model with circular cross section, composed of different wettability capillary wall was established. The model can describe the spontaneous oil-water imbibition of water-wet capillary, oil-wet capillary and mixed wetting capillary. Through numerical solution of the model equation, it is found that the component content of the capillary walls, the capillary radius and the oil-water viscosity ratio have great effects on the spontaneous oil-water imbibition. Effects of capillary inclination angle and inertia force on spontaneous oil-water imbibition are related to the capillary scale. Effects of capillary inclination angle and inertia force can be ignored in small radius capillary, while effects of inclination angle and inertia force can not be ignored in large radius capillary.

Статья посвящена исследованию разделения водонефтяных эмульсий. Большинство существующих месторождений находятся на завершающей стадии разработки, что характеризуется ростом обводненности добываемой нефтяной фракции. При наличии высокоустойчивых «застарелых» ловушечных нефтей для повышения эффективности и надежности процессов их обезвоживания используют методы разделения с применением деэмульгаторов. Наибольшее распространение, в настоящее время получили деэмульгаторы неионогенной природы. В работе была оценена эффективность трех деэмульгаторов, соответствующих государственным санитарно-эпидемиологическим правилам и нормативам: Эмалсатрон R2601-A, Химтехно-527, СНПХ-4114. Исследуемые деэмульгаторы успешно прошли испытания и могут быть рекомендованы к промышленному применению, так как обладают рядом преимуществ. The article is devoted to the study of the separation of oil-water emulsions. Most of the existing fields are at the final stage of development, which is characterized by an increase in the water content of the extracted oil fraction. In the presence of highly stable "old" trap oils, separation methods with the use of demulsifiers are used to increase the efficiency and reliability of their dewatering processes. The most widespread, at present, are demulsifiers of a non-ionic nature. The work evaluated the effectiveness of three demulsifiers that comply with state sanitary and epidemiological rules and regulations: Emalsatron R2601-A, Chemtechno-527, SNPH-4114. The studied demulsifiers have been successfully tested and can be recommended for industrial use, as they have a number of advantages.

This study developed a facile and environmentally-friendly method to prepare SiO2/silk fibroin (SF) composite melamine sponges modified using SF and hydrophobic SiO2 nanoparticles (NPs). During the preparation procedure, the SiO2 NPs were bonded to skeletons of porous sponges with the SF binding agent using a dip-coating method. The SiO2 NPs and SF with hydrophobicity constructed a rough surface. The obtained sponges possess a high absorption capacity of 70.9–160.8 times of its weight for various oils and organic solvents and a high water-contact angle greater than 151°. More importantly, the modified sponges showed good recyclability, and could return to its original shape even after 100 cyclic compression. The as-prepared sponge also showed high buoyancy outstanding elasticity, and maintained high absorption capacity even after 10 cycles of repetitive absorption-desorption. The prepared sponges could efficiently separate oil or organic solvents from oil–water mixtures, indicating that the SiO2/SF/MS sponges are promising candidates for remediating oil spills and oily wastewater.

CeO2 was synthesized by the co-precipitation method on the Cu mesh substrate and modified the surface of CeO2@Cu mesh by stearic acid (SA). The superhydrophobic behavior was ascribed to the combination of hierarchical micro-nanostructure of CeO2 and the hydrophobic alkyl groups from SA. The SA-CeO2@Cu mesh had antiacid and base stability and excellent durability as well as high separation efficiency. The separation efficiency can be up to 98.0% after separating 30 times.

Tremendous efforts have been exerted to develop effective and ecofriendly materials for separation of oil/water mixtures and emulsions. However, porous materials with superwettability for oil/water separation are usually fabricated from nonrenewable precursors, which contradicts with the concept of green development. Inspired by the cellular porosity and hierarchical organization of wood, biodegradable cut and sawed wood slices with different pore sizes were separately machined by a razor blade and a fine-toothed saw. The cut and sawed slices separately possessed rough single- and double-layer structures. After silylation with MTCS, both machined slices repelled water entirely but allowed the complete permeation of oils. The fragment-free cut slice with relatively large pore size was able to separate immiscible oil/water mixtures, while the fragment-covered sawed slice with relatively small pore size could separate water-in-oil emulsions. Compared with other wood slice by sawing, the section structure and superoleophilic property made the slices have a high oil flux for a series of mixtures and emulsions, which reached 72 kL m−2 h−1 and 464 L m−2 h−1, respectively. The flux was high even after 10 cycles, exhibiting favorable recyclable stability.

Summary Liquid-liquid phase flow in pipes merits further investigation as a challenging issue that has very rich physics and is faced in everyday applications. It is the main problem challenging the fluid flow mechanism in the oil and gas industry. The pressure gradient of liquid flow and flow pattern are still the topics of numerous research projects. In this paper, the emphasis is on further investigation to research the flow pattern, water holdup (HW), and pressure decrease for vertical, horizontal, and inclined flow directions of oil and water flows. Test section lines of 4.19-in. (106.426 mm) inner diameter (ID) and 5-m horizontal, 5-m inclined, and 5-m vertical test sections were serially connected. The experiments were conducted at 40°C using 2-cp viscosity oil and tap water, and oil density of 850 kg/m3, at the standard conditions. Fifty experiments were executed at 250 kPa at the multiphase flow test facility, with horizontal, upward (0.6° and 4°), downward (−0.6° and −4°) hilly terrain and vertical pipes. The oil and water superficial velocities were changed between 0.03 and 2 m/s. This evidence was obtained using video recordings; the flow patterns were observed, and the selection of each flow pattern was depicted for each condition. For horizontal and inclined flow, new flow patterns were documented (e.g., oil transfer in a line forms at the top of the pipeline, typically at high water rate, and water transfer at the lower part of the pipe at a high oil rate). The data were taken at each flow condition, resulting in new holdup and pressure drop. The results show that the flow rate and the pipe inclination angle have major impacts on the holdup and pressure drop performances. In the vertical flow, a clear peak was demonstrated by experiments after the superficial oil velocity reached a certain value. This peak is known as phase inversion point, where after this peak, the pressure starts declining as the superficial oil velocity increases. Also, slippage has been observed after varying inlet oil flow rates between the two phases. The experiments showed that with minor alteration in the inclination angle, the slippage was significantly changed. This study presented new experimental results (measured mainly at horizontal, inclined, and vertical flow conditions) of HW, flow pattern, and pressure drop. These findings are key evidence of the evolving oil-water and flowline estimate models.

Stimuli-responsive surfaces with wettability change between superhydrophilic and superhydrophobic are susceptible to oil contamination which often ruins the surface. Herein, a coating with pH-switchable wettability transition between superamphiphobic and superhydrophilic-superoleophobic is achieved by rationally designing oleophobic/pH-responsive polymer heterogeneous chemistry. Fabrics modified with this coating show repellency to both water and oils, while upon exposure to acidic water (pH = 1) the fabrics change to be superhydrophilic-superoleophobic within a short response time of5 s. More importantly, the superamphiphobicity of the fabric can be restored under mild alkaline condition (pH = 10), and the transition is reversible for many cycles. The effective in situ or ex situ wettability change under acidic/alkaline water treatment makes the coated fabric capable of separating oil-water mixture or even some mixtures of immiscible organic solvents. In addition, the coated fabric is also demonstrated to be promising as a new class of functional fabrics that provide protection against water and many oils in one condition, and can change to be hygroscopic, anti-static, oil-repellent and anti-oil-fouling in the other condition for improved wear comfort and self-cleaning.

An increase in the consumption of petroleum products in the transport and energy systems and intensive development of some branches of industry (especially petrochemical industry and oil refining) results in the accumulation of numerous waste in the form of waste oils, oil sludge and other oily liquids. The problem of waste disposal can be solved by using oily liquids as fuel for combustion at thermal power plants in order to produce thermal and electrical energy. To study the rheological characteristics of oil-water-coal emulsions based on anthracite with the solid phase concentration of 40%, an oil phase with the concentration of 49% (motor oils Motul 8100 X-cess 5W-40 and Comma Xtech 5W-30), water (10%) and nonionic surfactant (1%) as an emulsifier-stabilizer. It was found that the rheological characteristics of oil-water-coal emulsions depend not only on the granulometric composition of coal, but also on the viscosity of the dispersed medium (motor oils). Physicochemical and service properties of oil-water-coal systems under consideration allow using them as fuel. Given the availability and relative cheapness of feedstock, this type of fuel can successfully compete with traditional types of liquid fuels.

In this research, a modification of polyurethane (PU) sponge material has been made to obtain superhydrophobic-superoleophilic properties. The PU sponge was coated with several nanomaterials such as ZnO, Fe3O4+TEOS, and stearic acid by dip-coating and drop-coating methods. The tests include selective separation of oil and water with a magnetic response. Several types of oil and organic solvents were tested for absorption capacity. The results showed that the PU@ZnO@Fe3O4@SA sponge has a good absorption capacity, from 4.37 mL to 7.37 mL. The fabricated PU sponge could selectively separate oil from water with a separation efficiency above 99%. The fabricated PU sponge also could be magnetically driven by external magnetic fields. From the characterization using 3D OM, the water contact angle was 153.38°, which indicates that the PU@ZnO@Fe3O4@SA sponge is superhydrophobic. And from surface morphology obtained an average pore size diameter of 167.475 μm.

Hypothesis A binary mixture was used during injection with one water-miscible component and the other water-immiscible, which can help particles to migrate toward and then self-assemble at the interface. Experiments The ethanol-tetrachloromethane binary mixture was used to verify the self-assembly method, with the diameter of droplets being about 1 mm. As the ethanol diffused into the colloidal solution, the colloidal particles efficiently moved towards and self-assembled on the oil/water interface, while a colloidal particle film with high-coverage was able to rapidly form on the droplet surface even in an ultra-low concentration colloidal solution. The effects of ethanol concentration and particle concentration on self-assembly were investigated. Findings The driving force for self-assembly originated from the tension gradient generated by ethanol's concentration gradient at the particle/liquid interfaces, where the concentrations of ethanol and the colloidal solution had significant effects on self-assembly. The simulation and calculations results aligned well with experiments, providing the theoretical basis for this self-assembly method. Further, as-prepared magnetic particle-coated droplets transformed into a non-wetting soft solid, which had long lifetimes and could be precisely moved, coalesced, and transferred in various two-dimensional and three-dimensional liquid environments. Thus, wider applications are facilitated, such as droplet transfer, microreactor and other potential fields.

The separation of oil/water mixtures, polymer/water mixtures, or bubble/water mixtures has broad applications. In this paper, we aim at extending the well‐developed wettability‐based oil/water separation strategy to separate the mixtures of liquid polymers and water and separate bubbles from water. The micro/nanostructures are simply produced on a stainless steel mesh by femtosecond laser treatment to endow the mesh with superhydrophilicity in the air and superoleophobicity, superpolymphobicity, and superaerophobicity in water. The underwater superoleophobicity, superpolymphobicity, and superaerophobicity enable the structured mesh to have the ability of oil/water separation, polymer/water separation, and bubble/water separation. Water can pass through the mesh due to the superhydrophilicity of the laser‐structured mesh. Whereas, the oils, the liquid polymers, and the bubbles in water are intercepted by the structured mesh because such a water‐wetted mesh has strong repellence to oils (underwater superoleophobicity), liquid polymers (underwater superpolymphobicity), and bubbles (underwater superaerophobicity). As a result, the oil, the liquid polymer, and the bubble are successfully separated from water by using the as‐prepared superwetting mesh. We believe that the diversified wettability‐based separation processes will have wide potential applications in environmental protection, energy utilization, industrial manufacture, agricultural production, and so on.

Direct arylation polymerization (DArP) has emerged as an environmentally friendly, atom efficient method of synthesizing a variety of conjugated polymers. Here, we report a one-pot approach consist...

In order to reduce the frequency of marine environmental pollution accidents, marine oil-water separation numerical simulation method is developed. The oil-water separation hydrocyclone is used for emergency treatment to deal with the marine surface oil pollution, and the oil-water separation optimal control parameter calculation method based on the mathematical model of the flow field is used to simulate the oil-water separation performance of the device. The simulation results show that when the split ratio is 4.1%, the inlet pressure is 0.15MPa, the overflow pipe diameter is 3 mm, the oil droplet size is 101, and the large vertebral angle is 27, the hydrocyclone has good separation performance. Under these conditions, this method can be used as a reference method for dealing with oil spills in the ocean and has certain application value.

In this study, the coconut oil/water dual-phase dyeing system for developing salt-free reactive dyeing process for cotton was established. The selected dyes in this work were hot-dyeing reactive dyes, including C.I. Reactive Red 243, C.I. Reactive Blue 214 and C.I. Reactive Orange 70. A dual-phase dyeing system was performed under various coconut oil to water ratios and a comparative study was conducted on the conventional aqueous-based reactive dyeing in the presence and absence of salt. The results showed that the oil to water ratio of 3:1 imparted the highest colour yields (K/S values) and achieved a superior colour yield to the conventional aqueous-based dyeing. The results also pointed out that better dye fixation could be attained by dyeing cotton with the coconut oil/water dual-phase dyeing process under the optimum conditions. A comparable degree of dye exhaustion was observed for the aqueous-based and the dual-phase dyeing processes, however, the dye fixation was higher for the dual-phase dyeing, indicating less dye hydrolysis in this dyeing system. Consequently, superior colour fastnesses to washing and rubbing were obtained, less dye staining was observed in the case of dual-phase dyeing. A study on reusability of the coconut oil recovered from the spent dyebath for another reactive dyeing cycle was also conducted. The oil from the spent dyebath was directly taken to use without any further purification as a dual-phase medium along with water and the obtained result indicated a reusability potential of coconut oil. From this research, it infers that cleaner reactive dyeing process with the coconut oil/water dual-phase system for cotton could be developed.

Superwetting surfaces have the potential to address oil pollution in water, through their ability to separate the two. However, it remains a great challenge to fabricate stable and efficient separation structures using conventional manufacturing techniques. Furthermore, the materials traditionally used for oil-water separation are not stable at high temperature. Therefore, there is a need to develop stable, customizable structures to improve the performance of oil-water separation devices. In recent years, 3D printing technology has developed rapidly, and breakthroughs have been made in the fabrication of complicated ceramic structures using this technology. Here, a ceramic material with a gradient pore structure and superhydrophobic/superoleophilic properties was prepared using 3D printing for high-efficiency oil-water separation. The gradient pore structure developed here can support a flux of up to 25434 L/m2h, which is nearly 40% higher than that an analogous structure with straight pores. At 200 °C, the oil-water separation performance was maintained at 97.4%. Furthermore, samples of the material exhibited outstanding mechanical properties, and chemical stability in a variety of harsh environments. This study provides an efficient, simple, and reliable method for manufacturing oil-water separation materials using 3D printing, and may have broader implications for both fundamental research and industrial applications.

Pickering emulsions have attracted extensive attention due to their good properties including easy to manufacture, high stability, and superparamagnetic response. To improve the emulsifying transportation of crude oil, a Pickering emulsion of crude oil and water stabilized by Fe3O4 nanoparticles was prepared and its rheological properties were tested in this research. It was found that the particle size of dispersion droplet polymerization group in stable crude oil Pickering emulsion is negatively correlated with solid content and water content, and the equilibrium apparent viscosity {\mu }_{\text{ap}} of emulsion follows the power law fluid equation. Besides, this kind of Pickering emulsion has higher elasticity of interface membrane, which means by adding functional particles, it obtains good dynamic stability, and thus, has a great application property in crude oil industry.

Hydrophobic porous polymeric materials have attracted great interests recently as potential candicate for oil-water separation due to their high selectivity and sorption capacity. Herein, we present a green, simple and cost-effective method to change hydrophilic melamine formaldehyde (MF) foam to hydrophobic carbon nanotubes (CNTs) coated MF foam through an immersion process. The MF foam was produced from the MF resin which was synthesized in a laboratory by a condensation reaction between melamine and formaldehyde under alkaline condition with a molar ratio of melamine to formaldehyde of 1:3. The MF foam has an open-cell structure with the average pore diameter of 350 m, density of 25 kg •m-3 and porosity of 98 %. The as-prepared CNTs-coated MF foam exhibits high sorption capacity (23–-66 g/g) for oils and organic solvents, good recyclability and high selectivity.

Design and fabrication of smart materials with reversible wettability for oil-water separation have attracted worldwide attention due to the increasingly serious water pollution problem. In this study, a rough oxide coating with micro/nanoscale structures is developed on the 304 stainless steel mesh (SSM) by laser ablation. The smart surface with ethanol immersion and natural drying treatments shows the wetting conversion between underwater superoleophobicity and superhydrophobicity. Based on the wettability transition behavior, both light and heavy oil-water mixtures can be separated with the high separation efficiency. Moreover, after being exposed to various corrosive solutions and high temperatures, the smart surface still shows prominent environmental stability. Switchable surface with excellent properties should be an optimal choice to solve the environmental conditions that need to be addressed urgently.

Three-dimensional (3D)-printed membranes via stereolithography (SLA) are promising in oil–water separation, which is the key in the purification of industrial oily wastewater. To achieve gravity-dr...

Polymer waste is an “Achilles heel” in the product life cycle and can cause environmental pollution. Different methods can be used to reprocess such waste, including incineration and recycling, whi...

A large quantity of oil spills occurred have greatly endangered the natural environment and human survival health. Super-wetting materials with switchable wettability provide a good way to solve these problems efficiently and have been paid more and more attention. In this paper, we have successfully prepared an ethanol-triggered and highly stable superamphiphobic material with a switchable surface wettability by using zinc oxide (ZnO) particles and organic silane (PFDS) via a simple coating method. The superamphiphobic material can maintain high oil-repellent and water-repellent performances under various harsh conditions. Most importantly, the superamphiphobic material demonstrates the switchable wettability by ethanol treatment. In view of this fresh mechanism, it can separate various oil–water mixtures on-demand with high separation efficiency and flux. Surprisingly, the mixtures of highly corrosive liquids and oils can also be separated. In addition, the material also has excellent self-cleaning and anti-fouling capabilities and low surface adhesion, which can effectively avoid the pollution of pollutants in the air. All these advantages show that the as-prepared material can play a vital function in solving the related severe conditions of marine oil pollution and industrial wastewater.

Motivated by the need for improved understanding of physical processes involved in bacterial biodegradation of catastrophic oil spills, we review biophysical methods to probe bacterial motility and adhesion at oil–water interfaces. This review summarizes methods that probe bulk, average behaviors as well as local, microscopic behaviors, and highlights opportunities for future work to bridge the gap between biodegradation and biophysics.

Oil–inorganic material interactions at the oil/water interface have been extensively investigated as a fundamental research area. However, less focus has been placed on the oil/water interfacial pr...

Stratified flow is a common occurrence for various internal flow based industrial multiphase flow patterns. This involves fully or partially well-defined interface which continuously evolve with space and time. Hence stratified flow analysis essentially involves proper interface capturing approach. The present work focuses on the numerical analysis of oil-water stratified pattern using the Coupled level set and volume of fluid method (CLSVOF) in ANSYS Fluent in a two-dimensional channel. The work involves predicting the effect of density ratio, kinematic viscosity and surface tension coefficient on the mixture velocity and total pressure changes. At outset, the final conclusions may be gainfully employed in oil transportation pipeline, chemical industries and in pipeline flow control administration, etc.

Oil slick collection is an important way to treat oil-bearing wastewater and oil spill discharge. Superhydrophobic materials have attracted increasing attention in oil-water separation. An interesting method of constructing superhydrophobic meshes was presented. A mesh was coated with nanoscale SiO2 particles via electro-spray deposition to form microstructure mesh, which was then modified by odecyltrimethoxysilane to be superhydrophobic and superlipophilic. The whole construction process was easy without the requirement of complex equipment or chemical reagents. Stainless steel mesh, copper mesh and acrylic mesh were treated to be superhydrophobic. The oil slick collection rate reached 95% with high oil flow. The constructed superhydrophobic mesh could work at high temperature, low temperature or salty solution. After 20 times of use, the superhydrophobic meshes maintained a high collection rate. The significant advantages of this method are the ability to be free from material constraints, high collection rate and environmental friendliness, showing great application potential.

With the increasing occurrences of industrial oily wastewater emissions and oil spills, considerable efforts have been made to develop superhydrophobic materials for oil–water separation. Herein, we report a facile dipping-UV curing approach to fabricate superhydrophobic organosilicon/silica hybrid coating with crosslinked network structure on cotton fabric via thiol-ene reaction between thiol-functionalized silica nanoparticles (SH-SiO2 NPs) and acryloyloxy-terminated polydimethylsiloxane (A-PDMS-A). With the optimized mass ratio of SH-SiO2 NPs to A-PDMS-A at 0.2, the water contact angle of the fabric reached 155° and the water sliding angle was 8°, exhibiting excellent water repellency. Furthermore, the superhydrophobic cotton fabric possessed self-cleaning ability and good surface stability. In addition, the fabric was successfully applied for effective oil–water separation, and the separation efficiency reached up to 99.06%. Even after 15 cycles, the separation efficiency still maintained 98.93%, demonstrating excellent reusability. Our findings stand out as a new tool to fabricate UV-curable superhydrophobic coating on cotton fabric for efficient oil–water separation.

High-performance functional materials capable of simultaneously separating oil from water and removing water-soluble contaminants are critically demanded for wastewater treatment but remain highly challenging. Wood, a naturally occurring porous material composed of numerous open microchannels along the growth direction, may serve as a desirable scaffold for the development of efficient filtration materials for water treatment. Herein, by in situ deposition of silver nanoparticles (Ag NPs) within the channels of balsa wood, we developed dual-functional Ag/wood filters for simultaneous oil/water separation and organic dye removal from water in a one-step process. Owing to their superhydrophilicity and underwater superoleophobicity, the as-prepared Ag/wood filters can selectively separate water from oil with a high efficiency (∼99%). Moreover, benefiting from the catalytic activity of Ag NPs anchored to the surface of the wood channels, the Ag/wood filters effectively removed methylene blue (MB) from water during the oil/water separation process; the MB removal efficiency was highly dependent on the thickness of the wood filters. Specifically, the gravity-driven separation using a 6 mm-thick Ag/wood filter showed a high MB degradation efficiency of 94.03% and a water flux of 2600 L·m–2·h–1. The proposed wood-based filtration material features renewable, inexpensive raw materials, facile processing, and scale-up potential. Such dual-functional Ag/wood filters capable of rapid and efficient removal of insoluble oils and soluble pollutants from water in a one-step process offer a promising solution for wastewater treatment.

The influence of density of amino groups, nanoparticles dimension and pH on the interaction between end-functionalized polymers and nanoparticles was extensively investigated in this study. PS–NH2 and H2N–PS–NH2 were prepared using reversible addition–fragmentation chain transfer polymerization and atom transfer radical polymerization. Zero-dimensional carbon dots with sulfonate groups, one-dimensional cellulose nanocrystals with sulfate groups and two-dimensional graphene with sulfonate groups in the aqueous phase were added into the toluene phase containing the aminated PS. The results indicate that aminated PS exhibited the strongest interfacial activity after compounding with sulfonated nanoparticles at a pH of 3. PS ended with two amino groups performed better in reducing the water/toluene interfacial tension than PS ended with only one amino group. The dimension of sulfonated nanoparticles also contributed significantly to the reduction in the water/toluene interfacial tension. The minimal interfacial tension was 4.49 mN/m after compounding PS–NH2 with sulfonated zero-dimensional carbon dots.

The first step in calcium naphthenate deposition is supposed to be the formation of an interfacial gel by crosslinking between ARN tetrameric acid and Ca2+. Several aspects of the inhibition of the...

Velocity is an important parameter for fluid flow characteristics in profile logging. Particle tracking velocimetry (PTV) technology is often used to study the flow characteristics of oil wells with low flow velocity and high water cut, and the key to PTV technology is particle matching. The existing particle matching algorithms of PTV technology do not meet the matching demands of oil drops in the oil phase velocity measurement of oil-water two-phase flow with low velocity and high water cut. To raise the particle matching precision, we improved the particle matching algorithm from the oriented FAST and the rotated BRIEF (ORB) feature description and the random sample consensus (RANSAC) algorithm. The simulation and experiment were carried out. Simulation results show that the improved algorithm not only increases the number of matching points but also reduces the computation. The experiment shows that the improved algorithm in this paper not only reduces the computation of the feature description process, reaching half of the computation amount of the original algorithm, but also increases the number of matching results, thus improving the measurement accuracy of oil phase velocity. Compared with the SIFT algorithm and the ORB algorithm, the improved algorithm has the largest number of matching point pairs. And the variation coefficient of this algorithm is 0.039, which indicates that the algorithm is stable. The mean error of oil phase velocity measurement of the improved algorithm is 1.20 %, and the maximum error is 6.16 %, which is much lower than the maximum error of PTV, which is 25.89 %. The improved algorithm overcomes the high computation cost of the SIFT algorithm and achieves the precision of the SIFT algorithm. Therefore, this study contributes to the improvement of the measurement accuracy of oil phase velocity and provides reliable production logging data for oilfield.

Objective: In addition to lactic acid and sodium ascorbyl phosphate, which have whitening effects, beta-arbutin is a safe whitening agent for skin.Combining these three substances should reduce the concentration of each one in a formula and achieve an optimal whitening effect. In this study,microemulsions and water/oil/water (W/O/W) multiple emulsions were applied to produce a formula containing these whitening agents.Methods: All the active ingredients were formulated into microemulsions and W/O/W multiple emulsions with different concentrations of Tween 80and Span 80 as emulsifiers to obtain a stable formula. Twelve-week physical stability studies were performed for every formula at low (4±2°C), room(28±2°C), and high (40±2°C) temperatures.Results: The produced microemulsions were transparent with a mean droplet size of 15.50 nm. In addition, the W/O/W multiple emulsions containeddroplets within droplets, which were dispersed in a continuous phase with an inner droplet size of 0.15 μm and an outer droplet size of 0.37 μm. TheW/O/W multiple emulsions showed pseudoplastic thixotropic flow properties. Furthermore, the microemulsions were stable at low (4±2°C) androom (28±2°C) temperatures, while the W/O/W multiple emulsions were stable at room (28±2°C) and high (40±2°C) temperatures.Conclusion: It was concluded that the combination of beta-arbutin, lactic acid, and sodium ascorbyl phosphate was suitable for formulating intomicroemulsions as well as W/O/W multiple emulsions as whitening cosmetic products.

Electrowetting has drawn significant interest because of the potential applications of displays, lab-on-a-chip microfluidic devices, electro-optical switches, and so forth. However, electrowetting display (EWD) is monostable, which needs extra continuous voltage supply to keep contracting the oil. This paper is concerned with the simulation of two-phase liquid flow in three-dimensional EWD pixels with two electrodes (E1 and E2) demonstrating bistability, where power is only needed to move the oil droplet between two stable states. The effects of E1 geometry, E2 geometry, and E2 pulse characteristics on the dynamics of the oil droplet motion have been analyzed. Also, predictions of the transient states in four stages of the reversible bistable operation process have been carried out by employing the finite element method, in qualitative agreement with our experimental results of the monostable EWD and the existing literature. We seek to shed more light on the fundamental two-phase liquid flow in three-dimensional pixels exhibiting bistability for low power EWD and guide optimizing the electrodes to the perfect patterns with the aid of rigorous modeling.

The study anchors on developing a mechanistic model for oil-water separation. Over the years, researchers have been working on how to improve the quality of produced water effluent especially from oil and gas operations sent to the receiving waters. Despite the standard set for compliance by regulatory bodies like united nation agency, ministry, departments and other agencies both state and federal government including non governmental agencies the problem of meeting stipulated bench marks still persist. This study however looks into some variables perceived as being relative to improving or affecting produced water effluent from oil-water separator. Modeling of oil-water separation was based on the philosophy that a mathematical model can be established for the physical problems under investigation. These mathematical problems formulated were based on laws of conservation. Solving the model equation analytically however pose some problems. Hence they were solved by simulation using a computer soft ware SIMULINK a graphical extension of MATLAB with positive outcome since it has the ability to model non-linear systems. From the simulated analysis, increased flow rate creates turbulence in the system with resultant poor effluent quality, whereas also, from the simulated analysis, gradual increases in temperature improves oil-water separation from lower temperature of the fluid upstream thereby aiding improvement in effluent quality.

E grande a preocupacao com o lancamento de residuos oleosos, no meio ambiente principalmente por seus efeitos nocivos a saude humana. Emulsoes oleo/agua sao os principais poluentes emitidos pelos efluentes industriais e domesticos. As aguas oleosas em canais subterrâneos e em zonas costeiras apresentam serios problemas de poluicao da agua e necessitam urgentemente de solucoes. Dentre as diversas formas de tratamento de efluentes poluidos por oleo destaca-se a adsorcao, reconhecida como um metodo eficaz e economico para o tratamento de aguas oleosas. A adsorcao e um fenomeno fisico-quimico de superficie no qual uma substância de fase liquida ou gasosa e transferida para uma de fase solida, permanecendo ligada por interacoes fisicas ou quimicas. Neste sentido, a utilizacao de argilominerais como adsorvente tem-se mostrado interessante devido as propriedades destes materiais, apresentando assim grande relevância para a area ambiental. Neste trabalho, a argila bentonita denominada Brasgel foi caracterizada, e estudada como adsorvente no processo de remocao de oleo. A argila foi caracterizada a partir das tecnicas Difracao de raios X (DRX) para identificar a estrutura do material e Espectroscopia de Fluorescencia de Raios X por Energia Dispersiva (EDX) para determinacao da composicao quimica do material em termos qualitativo e semi-quantitativo. O teste de capacidade de adsorcao e inchamento de Foster indicaram o elevado potencial que a argila bentonita tem como adsorvente.