Oil Particles Research Articles

A Cotton Fabric Composite with Light Mineral Oil and Magnetite Nanoparticles: Effects of a Magnetic Field and Uniform Compressions on Electrical Conductivity.

Over the past few decades, tactile sensors have become an emerging field of research with direct applications in the area of biomedical engineering. New types of tactile sensors, called magneto-tactile sensors, have recently been developed. The aim of our work was to create a low-cost composite whose electrical conductivity depends on mechanical compressions that can be finely tuned using a magnetic field for magneto-tactile sensor fabrication. For this purpose, 100% cotton fabric was impregnated with a magnetic liquid (EFH-1 type) based on light mineral oil and magnetite particles. The new composite was used to manufacture an electrical device. With the experimental installation described in this study, we measured the electrical resistance of an electrical device placed in a magnetic field in the absence or presence of uniform compressions. The effect of uniform compressions and the magnetic field was the induction of mechanical-magneto-elastic deformations and, as a result, variations in electrical conductivity. In a magnetic field with a flux density of 390 mT, in the absence of mechanical compression forces, a magnetic pressure of 5.36 kPa was generated, and the electrical conductivity increased by 400% compared to that of the composite in the absence of a magnetic field. Upon increasing the compression force to 9 N, in the absence of a magnetic field, the electrical conductivity increased by about 300% compared to that of the device in the absence of compression forces and a magnetic field. In the presence of a magnetic flux density of 390 mT, and when the compression force increased from 3 N to 9 N, the electrical conductivity increased by 2800%. These results suggest the new composite is a promising material for magneto-tactile sensors.

Variables Impacting Silicone Oil Migration and Biologics in Prefilled Syringes

Prefilled syringes (PFS) as a primary container for parenteral drug products offer significant advantages, such as fast delivery time, ease of self-administration and fewer dosing errors. Despite the benefits that PFS can provide to patients, the silicone oil pre-coated on the glass barrels has shown migration into the drug product, which can impact particle formation and syringe functionality. Health authorities have urged product developers to better understand the susceptibility of drug products to particle formation in PFS due to silicone oil. In the market, there are multiple syringe sources provided by various PFS suppliers. Due to current supply chain shortages and procurement preferences for commercial products, the PFS source may change in the middle of development. Additionally, health authorities require establishing source duality. Therefore, it is crucial to understand how different syringe sources and formulation compositions impact the drug product quality. Here, several design of experiments (DOE) are executed that focus on the risk of silicone oil migration induced by syringe sources, surfactants, protein types, stress, etc. We utilized Resonant Mass Measurement (RMM) and Micro Flow Imaging (MFI) to characterize silicone oil and proteinaceous particle distribution in both micron and submicron size ranges, as well as ICP-MS to quantify silicon content. The protein aggregation and PFS functionality were also monitored in the stability study. The results show that silicone oil migration is impacted more by syringe source, siliconization process and surfactant (type & concentration). The break loose force and extrusion force across all syringe sources increase significantly as protein concentration and storage temperature increase. Protein stability is found to be impacted by its molecular properties and is less impacted by the presence of silicone oil, which is the same inference drawn in other literatures. A detailed evaluation described in this paper enables a thorough and optimal selection of primary container closure and de-risks the impact of silicone oil on drug product stability.

Effects of particle concentration and size on the dissipation rate and turbulent kinetic energy of oil

AbstractThe presence of particles in oil can change the quasi‐sequence structure of the turbulent flow of the oil, and it is extremely important to explore the turbulent energy dissipation rate of the particulate‐containing oil and ensure the safe and stable operation of the oil‐using equipment. Thus, the flow field of the oil containing particles in the pipeline was experimentally studied by a particle image velocimeter (PIV); the turbulent kinetic energy of the oil was calculated using the transient velocity vector field measured by the PIV; and the dissipation rate distribution was calculated using the large eddy PIV method. The influence of different particle sizes and particle concentrations on the normal distribution of the turbulent kinetic energy and dissipation rate was analyzed. The results show that the distribution of the turbulent kinetic energy in the normal direction is non‐unidirectional and in a parabolic shape. The 25 μm particle size has a great influence on the turbulence kinetic energy and the dissipation rate of the oil; with increasing particle concentration, the flow field distribution of the turbulent kinetic energy increases in the region near the wall, and gradually decreases in the central region. The turbulent kinetic energy distribution of the oil is in the shape of a quasi‐cosine; the flow field of the dissipation rate is larger in the near‐wall region and the central region and shows an inverted ‘W’ shape. This provides a theoretical basis for improving the efficiency of oil transportation, discussing the monitoring of particulate matter in oil, and reducing oil pollution.

New hybrid bio-composite based on epoxidized linseed oil and wood particles hosting ethyl palmitate for energy storage in buildings

In this study, the incorporation of ethyl palmitate (EP) as a bio-based phase change material (BPCM) in wood particles, the preparation and properties of the novel biocomposite for building applications were investigated. The wood particle-based composites hosting BPCM were produced by cold compression moulding. The EP impregnation step was optimized in terms of uptake and its ratio by post-addition of non-impregnated fibers. The optimized wood particles/EP ratio were combined with 37.5% epoxidized linseed oil (ELO) as a binder to produce a composite with energy storage function containing more than 99% bio-ingredients. The optimum BPCM content in the composite was 25%. The produced biocomposites were characterized by T-hystory, DSC, TGA, and a moisture buffer test. The results revealed excellent moisture buffer values (2.07 g/m2 RH%) according to the Nordtest protocol, significant thermal mass, ability to store excessive energy in terms of latent heat and maintain the temperature constant for longer time, good thermal stability and improved specific heat capacity when compared to a reference composite without BPCM. The effect of incorporating BPCM into biocomposite for regulating temperature fluctuations was confirmed by comparing test prototype cubes, with and without BPCM, subjected to temperature fluctuation between 0 and 40 °C.

Fucoidan-Containing, Low-Adhesive Siloxane Coatings for Medical Applications: Inhibition of Bacterial Growth and Biofilm Development.

The deposition of low-adhesive siloxane coatings is a current trend for the non-toxic control of bacterial growth and biofilm formation. Total elimination of biofilm formation has not been reported so far. The aim of this investigation was to study the ability of a non-toxic, natural, biologically active substance, such as fucoidan, to inhibit bacterial growth on similar medical coatings. The fucoidan amount was varied, and its impact on the bioadhesion-influencing surface characteristics, as well as on bacterial cell growth, was investigated. The inclusion of up to 3-4 wt.% brown algae-derived fucoidan in the coatings increases their inhibitory effect, more significantly on the Gram-positive bacterium S. aureus than on the Gram-negative bacterium Escherichia coli. The biological activity of the studied siloxane coatings was ascribed to the formation of a low-adhesive, biologically active surface top layer consisting of siloxane oil and dispersed water-soluble fucoidan particles. This is the first report on the antibacterial activity of fucoidan-containing medical siloxane coatings. The experimental results give reason to expect that relevantly selected, natural biologically active substances can be efficient in the non-toxic control of bacterial growth on medical devices and, as a result, medical device-associated infections.

Decreasing Asphaltene Precipitation and Deposition during Immiscible Gas Injection Via the Introduction of a CO2-Soluble Asphaltene Inhibitor

Summary In this study, the ability of dilute concentrations of toluene to act as a CO2-soluble asphaltene stabilization agent capable of inhibiting asphaltene precipitation during immiscible CO2 injection was assessed. Phase behavior results indicated that 1,000 to 20,000 ppm toluene could readily dissolve in CO2 at cloudpoint pressures that are well below the formation pressure and typical CO2 minimum miscibility pressure (MMP) values during gas-based enhanced oil recovery (EOR). Single-phase solutions of the modified gas (CO2/toluene) were then combined with asphaltenic oils in oil swelling phase behavior tests to demonstrate that the presence of toluene increased the amount of CO2 that dissolved into reservoir crude oil at a specified temperature and pressure. However, asphaltene precipitation diminished, apparently because the effect of the increased asphaltene solvent strength of toluene was more significant than the increased amount of CO2 (an asphaltene antisolvent) that entered the oil-rich phase. During the injection of CO2/toluene solution into cores initially saturated with crude oil and brine, compared to the injection of pure CO2, asphaltene deposition declined during the injection of CO2/toluene mixtures for asphaltenic volatile and intermediate oils from 3.7 wt% to 0.7 wt% and 5.9 wt% to 1.7 wt%, respectively. Based on the asphaltene particle-size analysis, the CO2/toluene mixtures can stabilize oil particles and simultaneously reduce asphaltene aggregation more effectively than pure CO2.

PAN/PAN-FPU Double-Layer Composite Nanofiber Air Filter Fabricated by Electrospinning for Filtering Oil and Salt Particles

PAN/PAN-FPU Double-Layer Composite Nanofiber Air Filter Fabricated by Electrospinning for Filtering Oil and Salt Particles

Phase change materials (PCMs) in solar still: - a review of use to improve productivity of still

This study examines the utilization of phase change materials as latent heat storage devices to boost the output of solar stills. These results show that compared to a solar still without phase change material, a passive solar still equipped with phase change material can boost its yield up to 120%. An active solar system equipped with phase change material can enhance productivity by as much as 700%. These findings show that productivity rises with PCM mass and declines with salty water bulk. Additionally, it is discovered that the PCM performs worse during the day than at night. The most often used PCMs in productivity improvement studies were likewise found to be organic PCMs (like paraffin), with inorganic and eutectic PCMs garnering very little attention. From the present study it is clear that most of researchers used paraffin as a PCM. Also mixing of nano particles (such as silicon oil and Cu nano particles) in the PCM gives better result. Paraffin wax with nAl2O3 enhanced the production by 60.53%.

Study on the Generation of Carbon Particles in Oil and its Effect on the Breakdown Characteristics of Oil‐Paper Insulation

AbstractThe partial discharge in the converter transformer will cause the carbonization of the insulating paper. The high concentration of free carbon particles generated from the insulating paper during the operation of the converter transformer will cause partial discharge, which will aggravate the insulation performance deterioration. For the bi‐directional interaction of carbon particles and partial discharge, the mechanism of insulating paper carbonization caused by partial discharge and the effect of carbon particles on the dielectric strength of oil paper are studied. In this paper, we construct a simulation system of amorphous cellulose to study the carbonization mechanism of insulating paper from the microscopic level. Furthermore, we build a DC voltage experimental platform to carry out partial discharge damage tests of oil‐paper insulation models and to measure the changes in the breakdown voltage with different carbon particle concentrations and diameters. The results show that partial discharge speeds up the cleavage rate of cellulose, generates low molecular hydrocarbon gas and water molecules, and the carbon atoms rearrange into PAH‐like molecules with aliphatic side chains. The surface of the insulating paper will carbonize, then form free carbon particles after peeling off. Afterward, the carbon particles in insulating oil accumulate in the high electric field area and attach to the insulating paper, which will cause electric field distortion and reduce the dielectric strength of oil‐paper insulation. With the increase of carbon particle concentration and diameter, the breakdown voltage of oil‐paper insulation decreases gradually. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.

The Role of Bacteria in the Formation and Migration of Oil-Particle Aggregates (OPAs) after Marine Oil Spills and the Associated Mechanism.

Oil spills interact with mineral particles to form oil-particle aggregates (OPAs), which promotes the oil's natural diffusion and biodegradation. We investigated the effect of bacteria on the formation and vertical migration of OPAs under different concentrations and types of particles and proposed and elucidated an oil-particle-bacteria coupling mechanism. The depth of particle penetration into oil droplets (13-17 μm) was more than twice that of the nonbacterial group. Oil that remained in the water column and deposited to the bottom decreased from 87% to 49% and increased from 14% to 15% at high/low concentration, respectively. Interestingly, the median droplet diameter showed a negative correlation (R2 = 0.83) and positive correlation (R2 = 0.60) at high/low concentration, respectively, with the relative penetration depth first proposed. We further demonstrated that bacteria increased the penetrating depth by a combination of reducing/increasing the interfacial tension, reducing the oil amount (C17-C38) in the OPAs, and increasing the particle width. These effects reduced the droplet size and ultimately changed the vertical migration of OPAs. Finally, we provided a simple assessment of the vertical distribution of OPAs in nearshore environments based on experimental data and suggested that the role of bacteria in increasing the depth of particles penetrating into the oil droplets should not be ignored. These findings will broaden the research perspective of marine oil spill migration.

PROSPECTIVE PHYSICO-CHEMICAL METHODS OF INCREASING THE RECOVERY (EOR) FOR OIL FIELDS WITH THE CATEGORY OF HARD-TO-EXTRACT OILS

It is known that many technologies to improve the oil recovery factor in fields at a late stage of development are being used. However, there are no universal technologies that ensure the effective displacement of residual oil in the reservoir by changing the filtration and volumetric parameters of rocks and the rheological properties of fluids depending on the geological characteristics of the reservoirs. In the article, based on the analysis of well-known works carried out on the selection of the appropriate oil for displacement oil in the reservoir, taking into account changes in some reservoir parameters, research work was conductedwith the purpose to prepare a new composition. The question of searching for a composition capable of maintaining oil-displacing properties at different temperatures in reservoir conditions, not changing its viscosity at large temperature differences, and also capable of retaining the properties of removing oil particles absorbed there from the surface in contact with the reservoir is relevant. the surface of the rock was examined by laboratory studies. The viscosities of the found composition at various temperatures were determined using a viscometer, and the optimal composition with a stable viscosity was determined by replacing the components with numerous laboratory experiments. Under laboratory conditions, the process of displacement of oil under various compositions with a slug of the composition at different temperatures was carried out. The results obtained are satisfactory, and the effective behavior of the composition at bed temperatures of 30-80 0C has been experimentally confirmed. If we take into account that the compositions injected into the reservoir undergo certain changes under the influence of reservoir temperature and pressure, then certain changes in its properties will inevitably occur when the composition comes into contact with reservoir fluids. Therefore, the ability of the prepared composition to form a precipitate or gel upon contact with various formation waters was also studied. The results of laboratory studies of physical and chemical technologies for enhanced oil recovery in fields treated by water injection and thermochemical treatment are presented. These technologies can be used in reservoirs with hard-to-recover reserves of high-viscosity oil. Keywords: viscosity, residual reserve, bed, surfactant, gel, oil displacer.

Pressure Drop Dynamics during Filtration of Mixture Aerosol Containing Water, Oil, and Soot Particles on Nonwoven Filters.

The pressure drop dynamics during the filtration of three-component mixture aerosols are investigated and compared with two and single-component aerosols. The main area of interest is the effect of the addition of a small quantity of liquid (oil) and solid (soot) particles during the filtration of aerosol containing water mist. In addition, calculations of the change in filter mass during oil aerosol filtration have been carried out and compared with the experimental results. The new, improved filtration efficiency model takes into account a better coefficient fitting in the filtration mechanism equations. The limitations in the change in fibre diameter and packing density resulting from the filter loading have been implemented in the model. Additionally, the calculation model employs the fibre size distribution representation via multiple average fibre diameters. The changes in fibre diameter are dependent on each fibre's calculated filtration efficiency. The improved filtration model has been utilised to predict the mass change of the filters during the filtration of pure and mixture aerosols. The pressure drop calculation model based on changes in filter mass has been formulated. The model is then utilised to calculate pressure drop changes resulting from the filtration of the oil aerosol and water and oil mixture aerosol.

A further investigation to mechanism of the electrorheological effect of waxy oils: Behaviors of charged particles under electric field

Exposing waxy oils to an electric field may significantly improve their cold flowability. Our previous study has shown that interfacial polarization, i.e., charged particle accumulation on the wax particle surface, is the primary mechanism of the electrorheological behavior of waxy oils. However, the way that charged particles interact with wax particles under an electric field remains unknown. In this study, we found no viscosity and impedance change for two waxy crude oils after their exposure to a high-voltage electric field. However, the yield stresses were reduced obviously. We thus proposed that the collision of colloidal particles such as resins and asphaltenes with the wax particles could be an essential mechanism that the wax particle structure was weakened. To verify this hypothesis, a series of ad hoc experiments were carried out, i.e., by performing electrorheological tests on model waxy oils containing additives removable under an electric field, including electrically-neutral colloidal particles (Fe3O4), charged colloidal particles (resins), and oil-soluble electrolyte (C22H14CoO4), respectively, and demonstrated that upon application of a high-voltage electric field, charged particles in a waxy oil may move and thus collide with wax particles, and consequently adhere to the wax particle surface. The particle collision results in damage to the wax particle network, and the electrostatic repulsion arising from the adhesion of the charged particle on the wax particle diminishes attraction between wax particles. This study clarifies the process of interfacial polarization.

Injection-Locked-Oscillation-Based Active Sensor on Dual-Mode Folded SIW Rectangular Cavity for High-Resolution Detection to Moisture and Fe Particle in Lubricant Oil

The TE201 and TE102 modes of the folded substrate integrated waveguide (FSIW) rectangular cavity (RC) are used as frequency-selective elements to be coupled with a negative-resistance circuit (NRC) to implement a dual-mode negative-resistance (NR)-based voltage-controlled oscillator (VCO). Then, a wideband low-power-level signal from vector network analyzer (VNA) is injected into the NR-based VCO to implement an injection-locked-oscillation (ILO)-based dual-mode FSIW RC active sensor for separately detecting moisture and Fe particle in lubricant oil. With the help of an external static H-field, the lubricant oil passes through the shared sensing region where the strong time-harmonic H-field of TE201 mode and the E-field of TE102 mode are highly concentrated. Then, a LabVIEW-based real-time measurement system for ILO frequency is developed to characterize the moisture content in the volume fraction from 0.025% to 0.5% and Fe particle concentration from 40 to 200 mg/dL. The measured ILO frequency self-shift noise <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta f_{\mathrm {self}}$ </tex-math></inline-formula> of the TE201 (TE102) mode of the active sensor loaded by pure lubricant oil is 15 kHz. The ILO frequency shift <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta f_{s}$ </tex-math></inline-formula> of the dual-mode active sensor loaded by lubricant oil sample is recorded to demonstrate a high sensitivity (2.8 MHz/vol% for moisture and 5.8 kHz/mg <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\cdot $ </tex-math></inline-formula> dL <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{-1}$ </tex-math></inline-formula> for Fe particle) and low limit of detection (0.025% for moisture and 40 mg/dL for Fe particle).

Modeling and Simulation of Coalescence in the Context of Oil Mist Filtration

Today, aerosols are generated in many industrial processes like machining or in pneumatic compressors. The harmfulness of these droplets often lies in the liquid itself, as it can be toxic or cancerous while exhaled natural aerosols can carry pathogens. For health protection, the filtration of these aerosols is an important task. The wetting properties of the fibers have a large influence on the filtration efficiency and coalescence of droplets on the fibers. Oleophilic fibers are better in capturing the oil particles, while drainage increases using oleophobic fibers. For improved efficiency and drainage properties, a mixed-wet fiber system could therefore be advantageous. Describing droplet capture and coalescence in filter-scale simulations is computationally extremely demanding. We present a new approach for simulating oil mist deposition and droplet coalescence, specifically accounting for the wettability of the fibers, especially for mixed-wet filter media. The aim is to gain a more realistic pressure loss of a fibrous filter structure which takes the presence of the filtered phase into account as well as the coalescence of the liquid phase on the fibers depending on the wettability and the fluid parameters. Our approach is to model the shape of deposited droplets via weighted distance maps, according to the contact angles. Starting from a sphere, the shape is fitted on the solid surface such that the contact angle is met. For validation purposes, volume-of-fluid-based simulations were set up using the same droplet-fiber system as a reference to compare the droplet shape and pressure loss in the presence of oil droplets on the fiber surface.

Extending the shelf life of soft cheese using nanoencapsulation

The study conducted to use the encapsulation of Nigella sativa oil to increase its thermal stability and making it more resistant to oxidation, lipolysis and use it to enrich soft cheese. Nigella Sativa oil particles was prepared by encapsulating oil with chitosan nanoparticles (NSP) by using the ionotropic gelation technique. The prepared size of the nanoparticles was 70.93 nm. This study included Four treatments to produce soft cheese. In the 1st treatment(M1) 0.5% of the solution was added to NSP particle pasteurized milk (m1), while the 2th treatment(M2) treatment 1% of liquid solutions to NSP was added to pasteurized milk. A 0.5% and 1% of liquid solutions NSP were added to cared treatments (M3 and M4), respectively. The 5th treatment (M5), the soft cheese was used as a control and left without additions. All treatments were kept in cooling at a temperature of 7 ± 2o C for 14 days for conduct the physiochemical and microbiological examinations. The results showed that the coating of Nigella sativa oil with chitosan and in the nano capsulate form increase the resistance of this oil to the manufacturing conditions, which led to an increase in its resistance to heat and oxidation processes. Also, the addition of nanoparticles to soft cheese in two percentages 0.5 &amp; 1% caused increase the preservation ability of cheese during the 14 days of cooling storage.

Hindcast of oil spill pollution in the East China Sea in January 2018

In this study, an integrated model is developed for studying the Sanchi oil spill event, which occurred in the East China Sea in January 2018. The results of the Advanced Research Weather Research and Forecasting model (WRF-ARW) as well as the Princeton Ocean Model (POM) are used for meteorological forecasting and the hydrodynamic simulations, respectively. These data are adopted as inputs for the OpenOil, a sub-module of OpenDrift, for the oil spill model. Some reference experiments are examined for short-term hindcast. The satellite image is used to validate the numerical result. The oil slicks of the satellite image and the numerical result are of similar shapes. Quantitatively, the simulated oil slick and that from the satellite image are located closely and have similar dimensions of 56 km by 34 km and 54 km by 29 km, respectively. It is found that the accurate results can be obtained by the proposed integrated model with the high-frequency (hourly) and high-spatial-resolution data as inputs, and the wind drift factor has to be added. The long-term 1-month simulation showed that most of the oil particles would move to the northeast of the sinking location and be trapped by the Kuroshio current.

Influence of Oil Content on Particle Loading Characteristics of a Two-Stage Filtration System

Filter media may encounter aerosols mixed with solid and oil ingredients from various sources, such as industries, transportation, and households, in the air purification process, while the influence such oil content has on the loading performance of single-stage and two-stage filtration systems is under-reported. Thus, this study aims to evaluate oil fraction effects on the loading performance of single-stage and two-stage filtration systems. First, to reveal the oil–solid mixed particle deposition mechanisms, the filter media parameters, i.e., specific cake resistance ε and cake porosity K2, were tested, indicating that a slight amount of oil can increase the dust holding capacity (DHC) of filters by forming a more porous cake, while an excess of oil results in reduced DHC by forming impermeable liquid films on the solid skeleton. Further two-stage experimental results indicate that the effectiveness of a pre-stage filter can be significantly affected by the properties of incoming aerosol and main-stage filters. The utilization of a pre-stage filter unintentionally deteriorated the service lifetime of the main-stage filter when challenged with contaminants with certain oil particles. This counter-intuitive negative phenomenon is due to the special loading behaviors of oil–solid mixed particles. The existing pre-stage filters allow a higher fine oil particle fraction to reach the main-stage downstream, while the induced cake filtration scenario leading to a film clogging scenario adversely reduced the lifetime of the main-stage filter. The findings suggest that the feasibility of a pre-stage in the filtration system requires compressive evaluations according to the specific oil-coated contaminants.

Method for Identifying Materials and Sizes of Particles Based on Neural Network

Ships are equipped with power plants and operational assistance devices, both of which need oil for lubrication or energy transfer. Oil carries a large number of metal particles. By identifying the materials and sizes of metal particles in oil, the position and type of wear can be fully understood. However, existing online oil-detection methods make it difficult to identify the materials and the sizes of metal particles simultaneously and continuously. In this paper, we proposed a method for identifying the materials and the sizes of particles based on neural network. Firstly, a tree network model was designed. Then, each sub-network was trained in stages. Finally, the identification performance of several key groups of different frequencies and frequency combinations was tested. The experimental results showed that the method was effective. The accuracies of material and size identification reached 98% and 95% in the pre-training stage, and both had strong robustness.

Changes in the physicochemical properties of rapeseed‐derived protein complexes during enzyme‐assisted wet milling

AbstractOilseeds need to be exploited not only for the oil but also as a source of functional protein‐rich ingredients for food. This work evaluated the physicochemical properties of the colloidal fraction resulting from wet milling of rapeseed, used as a model oilseed. The extraction was conducted either at natural pH (5.7) or at alkaline pH (8.5), with or without addition of a commercial pectinase. The slurry was mixed for 4 h at room temperature, and then pressed at the same pH or after shifting to alkaline/acidic pH. The resulting extract, rich in oil and protein particles, showed differences in particle size, microstructure, and composition. The oil and protein yields in the extract (in relation to the amount originally in the oilseed) ranged between 60% and 70%, with a significant increase in protein recoveries with addition of pectinase, regardless of the pH. A protein concentrate, containing between 25% and 42% protein on dry matter, depending on the treatment was obtained after centrifugation, together with a fiber precipitate and an oil fraction. The composition of the concentrates varied, with the highest purity found for extracts at pH 5.7, showing a nearly complete physical separation of the oleosomes by low‐speed centrifugation. All concentrates showed similar protein composition, as analyzed by gel electrophoresis. The amino acid composition was also similar among the treatments. This work evidences the critical role played by biopolymers' interactions in forming different colloidal structures, with clear consequences on the functionality of the final ingredient.