Oil Particle Size Research Articles

Aviation piston engines on-condition maintenance – proposal

The article presents a proposal of the established in the Institute of Aviation program and tools that are to enable General Aviation Operators in our country to perform on-condition maintenance of piston engines. Program apart from the existing (strictly supervised) Engine Manual tasks, introduces new mandatory maintenance activities such as: monitoring of engine parameters during cruise and climb, with determination of their diagnostic tolerance limits (never been performed in the maintenance practice), oil spectrographic analysis, also with determination of tolerances and oil particle size monitoring. The article shows results of half year long monitored exploitations of Continental IO -240-B engines installed on Diamond DA20-C1 „Katana” aircraft.

Effect of the properties of oil, particles, and water on the production of Pickering emulsions

Oil-in-water Pickering emulsions were prepared using a standard mixing configuration. Emulsification experiments were performed in an unbaffled tank using an off-centered pitched-blade turbine. Regular and modified glass beads were used as a stabilizer, and their size, concentration, and wettability effects were investigated as were oil viscosity and the properties of the aqueous phase (pH and salinity). Our findings highlighted the importance of the stabilization mechanism in the emulsification process, which is different from that of surfactant-based systems. The stabilization mechanism can be divided into four steps: (1) droplet formation by breakage, (2) particle/droplet approach and collision, (3) particle adsorption, and (4) formation of the particle network. Emulsification efficiency was mainly quantified by size distribution measurements using a Mastersizer 3000 (Malvern). Our results showed that droplet stabilization is closely related to particle/droplet approach, collision, and initial adsorption and that it is highly sensitive to oil viscosity and particle size and wettability, while the properties of the aqueous phase influence stabilization mainly through their effect on particle interactions (flocculation). The smallest droplets with the narrowest distribution were obtained with small particles, low oil viscosities, and good oil/particle affinity. It was possible to modulate the effects of particle size and oil viscosity by increasing oil/particle affinity. We also showed that stabilization efficiency is dependent on the particle fraction.

重晶石粉末表面偶联剂改性和表征

利用自制的钛酸酯偶联剂，采用干法改性工艺，对天然重晶石表面进行改性研究，测试了改性前后重晶石吸油量、接触角、活化指数等性能指标，通过对比发现改性后重晶石表面性能有了明显改变，达到了从亲水性向疏水性的转变。粒径分布结果表明改性后颗粒未发生明显团聚现象，而通过扫描电子显微镜、热重和傅里叶变换红外光谱分析表征，观察到颗粒形貌，失重率及表面状态的变化，验证了其改性后偶联剂与重晶石的表面键合作用，并由此为基础探讨了其改性机理。 Natural barite powder was modified with the method of surface coating by self-made titanate coupling agent. The effect of modification was evaluated by the oil absorption value, contact angle, activation index, and particle size distribution. By comparison, there is significant change on the surface performance of barite after modification, from hydrophility to hydrophobicity. No obvious aggregation of particles was found by the result of particle size distribution. Through the characterization of FTIR, SEM, and thermal analysis, the change of morphology, weight loss ratio, and surface state were observed. These results verified the chemical bonding between the titanate coupling agent and the surface of barite after modification. Based on the results, the modification mechanism was discussed.

Microencapsulation of Anchovy (E ngraulis encrasicolus L.) Oil: Emulsion Characterization and Optimization by Response Surface Methodology

The aim of the present study was to evaluate the anchovy (Engraulis encrasicolus L.) oil emulsion characterization and to optimize the anchovy oil microencapsulation process by spray drying. Response surface methodology was employed to study the effects of inlet air temperature (160–190C), peristaltic pump rate (20–40%) and ratio of coating to oil (2/1–4/1) on the oil particle size, microencapsulation efficiency (MEE), peroxide value (PV), bulk density, Carr index (CI) and dry matter. The inlet air temperature showed a significant (P < 0.05) influence on the MEE, PV and CI of samples. The peristaltic pump rate and ratio of coating to oil affected significantly (P < 0.05) only the MEE and PV. The optimal drying condition for microencapsulation of anchovy oil was found as 164C the inlet air temperature, 25% the peristaltic pump rate and 4/1 the ratio of coating to oil. Practical Applications Anchovy fish (Engraulis encrasicolus L.) was succesfully encapsulated with gum arabic and maltodextrin. The response surface methodology (RSM) was employed to optimize the microencapsulation condition of anchovy oil. Inlet air temperature and ratio of coating to oil were found as the main independent variables.

Graphene Size Control via a Mechanochemical Method and Electroresponsive Properties

Highly dispersible graphene oxide (GO) sheets of uniform submicrometer size were successfully fabricated from pristine graphite using a simple mechanochemical process. The GO flake morphology was transformed into a spherical form, and the density was decreased slightly via the ball-milling process. Ball-milled GO can be used as an electrorheological (ER) material because of its small particle size, low conductivity, and outstanding dispersibility in silicone oil. We found that the 2-h ball-milled GO-based ER fluid had the best ER performance (shear stress of 78.5 Pa and 630% ER efficiency), which was double that of the nonmilled GO-based ER fluid. The response time to form a fibrillar structure along the applied electric field direction and the recovery time to the starting level decreased with increasing ball-milling time. Additionally, the retarded settling velocity of isolated GO sheets and the electrostatic repulsion between oxygen functional groups on the GO sheets combined to improve the antisedimentation property. The ability to control the size of graphene sheets is a great opportunity to advance graphene commercialization in a high-quality, scalable production setting.

Evaluation of hemicellulose as a coating material with gum arabic for food microencapsulation

In this study, hemicellulose-based coatings were assessed for use in microencapsulated fish oil. The fish oil emulsions were prepared using the solutions of gum arabic (GA), gum arabic-hemicellulose (GA-HC) and hemicellulose (HC) as the coating materials, amended with maltodextrin as a cheap filler material. The fish oil was then encapsulated with these emulsions using the spray drying method. The effects of the hemicelluloses on the emulsions and the formed microcapsules were evaluated by physical and chemical tests. Although the GA-HC and HC emulsions showed higher creaming index and apparent viscosity values than that of the GA samples, all emulsions showed shear-thinning behavior. The oil particle size of the emulsions was found to be affected by the apparent viscosity. The HC emulsions contained oil particles with the largest size among all samples (p<0.05). On the other hand, oil particle sizes of the reconstituted microcapsules were not significantly different (p>0.05). Scanning electron microscope (SEM) was also used to visualize the morphological characteristics of all microcapsules. The hemicellulose microcapsules (GA-HC and HC) had fewer dents than the GA microcapsules. The microencapsulating efficiency (MEE) of the GA microcapsules was found higher than that of the GA-HC and HC microcapsules. The HC microcapsules had the lowest water activity (0.049aw). The wetting time of GA and GA-HC microcapsules were not significantly different (p>0.05). As a result, this study showed that hemicelluloses can be used as the coating material with gum arabic for food microencapsulation.

沈船からの流出油に対する油処理剤の水中散布による分散性能に関する研究

Experiment to investigate the dispersive effects of underwater dispersant, namely, the reduction of rise velocity of oil droplets and the increase of diffusion area, have been carried out. A beaker test of mixed sample of Marine Diesel Fuel (MDF) and dispersant was carried out and the particle size distribution was measured to confirm the pertinent ratio of dispersant. As the dispersant is a solution of nonionic surfactant and hydrocarbon solvent, the relation between hydrocarbon solvent and MDF was investigated by Gas Chromatography (GC) analysis. The oil concentration in water was confirmed to be linear to the oil dispersant ratio. As the dispersant reacts to water, the mixed sample of MDF and dispersant was discharged from the nozzle installed at the bottom of a water tank 3 m in height. The behavior of this mixed sample was analyzed by high resolution camera. PTV, PIV, and concentration change method were used to analyze the rise velocity and diffusion area of the sample. It turned out that the reduction of rise velocity of oil droplets and the increased diffusion area of the sample were the effect of the dispersants. Furthermore, the rise velocity of oil droplets was estimated from the size of oil particles.

Comparing Carboxymethyl Cellulose and Starch as Thickeners in Oil/Water Emulsions. Implications on Rheological and Structural Properties

The study reported here aims to obtain information on how thickener type and concentration, and oil content influence rheology, particle size, particle charge and microstructure in o/w model emulsions. Emulsions were prepared at two oil concentrations (5 and 30 % wt/wt), each with three CMC concentrations (0.2, 0.3, and 0.4 % wt/wt), or three starch concentrations (2, 3, and 4 % wt/wt). For each oil concentration, a sample without any added thickener was prepared as reference. Both CMC and swollen starch granules showed a dominating effect on emulsion flow behavior, although the presence and concentration of fat droplets also played an important role. Viscoelasticity of CMC-based emulsions mainly depended of oil concentration whilst in starch-based emulsions the most influential ingredient was starch. A similar situation was detected in terms of particle size distribution; CMC effect was dependent on oil content and starch effect was mainly related to the volume occupied by swollen granules. Differences in microstructure and particle size distribution between CMC and starch emulsions were related to their rheological behavior. Apart from enabling the acquisition of food emulsions with different composition but with similar rheological behavior by adding different hydrocolloids, here we consider thickener effect on other properties in order to obtain food emulsions with adequate characteristics.

Effect of Homogenization Pressure and Oil Load on the Emulsion Properties and the Oil Retention of Microencapsulated Basil Essential Oil (Ocimum basilicum L.)

The objective of this work was to evaluate the influence of oil concentration and homogenization pressure on the emulsion and particle properties during the microencapsulation of basil essential oil by spray drying, using gum arabic as the wall material. Experiments were planned according a 22 rotational central composite design. The independent variables were oil concentration with respect to total solids (10–25%) and homogenization pressure (0–100 MPa). Emulsions were analyzed for droplet mean diameter, stability, and viscosity, and particles were analyzed for oil retention, moisture content, particle size, and morphology. Emulsion viscosity was not affected by any of the independent variables. The increase in the homogenization pressure from 0 to 100 MPa resulted in smaller emulsion droplet size (down to 0.40 µm) and, consequently, higher oil retention (up to 95%). On the other hand, higher oil loads (25%) resulted in poorer oil retention (51.22%). Microencapsulation of basil essential oil using gum arabic as the wall material proved to be a suitable process to obtain powdered basil essential oil, presenting great oil retention with the use of lower oil concentration and higher homogenization pressure.

Coalescence filtration of ship oil bilge water with an nonwoven fabric

This article examines phenomena occurring in the process of oil-water emulsion flow through a coalescence fabric filter. The authors determined the flow of oil-water mixture through a fabric partition, the efficiency of filtration ηF and the distribution of oil particle size do by using a Malvern analyzer gauge. The results, presented graphically and in tables, are considered as satisfactory as they meet the standards of Resolution MEPC 60/(33) IMO for shipboard equipment.

Adsorption of emulsified oil from spent metalworking fluid using agro-waste of Cajanus cajan

Safe disposal of spent cutting fluids generated by the use of semi-synthetic fluids as coolant in material processing industries is a serious problem. The ultra-filtration method is mostly employed for the processing of spent cutting fluids. This method is costly and difficult to adopt by small and medium sized industries. In this study, efforts have been made to produce adsorbent using agro-waste, i.e. stem of Cajanus cajan in unmodified and modified form for the removal of emulsified oil. Batch adsorption studies demonstrated that chemically modified adsorbent has significant capacity to absorb emulsified oil. The parameters investigated in this study included pH, temperature, contact time, initial oil concentration, adsorbent dosage and particle size. The data obtained was also analysed using Langmuir isotherm model and linear plots conforms its applicability. The dimensionless equilibrium parameter, RL, signified a favourable adsorption of oil. The adsorption process appeared to follow pseudo second-order kinetics.

The Coalescence Stability of Protein-stabilized Emulsions Estimated by Analytical Photo-centrifugation

Various protein solutions were studied in order to quantify the emulsifying activity of proteins, and to explore oil-water interfacial tension, oil particle size analysis, and oil phase separation behaviors in protein-stabilized oil-in-water (O/W) emulsions. Three proteins, bovine serum albumin (BSA), β-lactoglobulin (β-lg), and β-casein (β-ca), were employed to disperse hexadecane in various pH and ionic strength solutions in a wide range of oil-water ratios. It was confirmed that the volume mean oil droplet diameter, d(43), changed depending on the oil content, the pH, the ionic strength, and the used protein. In a dilute protein solution (0.01 %) at pH 7, droplet size increased with oil content in so-called surfactant-poor regimes (e.g., above 5%, 10%, and 20% oil content for BSA, β-lg, and β-ca emulsion, respectively) but remained constant at ca. 10 mm, 6 mm, and 20 mm, respectively, in lower oil content surfactant-rich regimes. In surfactant-poor regimes, the most important factor determining the oil drop size was the threshold amount of protein adsorption onto the oil-water interface. In surfactant-rich regimes, on the other hand, it is suggested that drop size may be governed mainly by the mechanical strength of protein films covering the oil drops during emulsification, and this was quantified by the critical osmotic pressure, P(CR). In this study, the P(CR) was measured conveniently in the oil phase separation experiments for protein-stabilized emulsions using analytical photo-centrifugal apparatus. The correlation between the P(CR) and oil droplet size prepared by emulsification at different pH and ionic strength media is discussed.

Sono-synthesis of Mn 3O 4 nanoparticles in different media without additives

Hausmannite (Mn 3O 4) nanoparticles were prepared by ultrasound in various media for the first time under ambient conditions without any additives. The synthesis was carried out by direct sonication of manganese acetate in water. The nanoparticles with high crystallinity and sizes less than 4 nm appeared after 3 min of sonication. Water in oil emulsion was selected as another medium for the synthesis. In this case, the water phase containing manganese acetate was dispersed into the oil phase. Two different types of oil were chosen as a medium for the synthesis—paraffin as a mineral oil; olive and almond as vegetable oils. In all selected media, hausmannite was prepared with different sizes, shapes, and crystallinity. In the vegetable oils, the nanoparticles were larger than the nanoparticles prepared in water but the crystallinity was lower than in the water phase. In contrast, the crystallinity of the product in mineral oil was higher than in vegetable oil and lower than in water but the particle size in mineral oil was larger than the two other media. TEM (transmission electron microscopy) and XRD (X-ray diffraction) were used for characterizing the products. The XRD patterns confirmed that different media yielded to the same product, Mn 3O 4 nanoparticle. The TEM images showed that the size and shape of nanoparticles were different in the different media. In vegetable oil, nanoparticles had a spherical shape with maximum ∼7 nm in size. Using mineral oil, the shape of nanoparticles was diamond form and maximum ∼50 nm in size. In water phase, the size of nanoparticle is less than ∼4 nm with spherical shape.

A Pin-on-Disk Experimental Study on a Green Particulate-Fluid Lubricant

The present investigation analyzes a green, petroleum-free lubricant that is produced by mixing two environmentally benign components—canola oil and boric acid powder. To study the influence of boric acid particle size and solid volume fraction on the proposed lubricant performance, pin-on-disk experiments were conducted with spherical copper pins (radius 6.5mm) and aluminum disks (Ra=1.35μm). Friction coefficient measurements were taken at more than 20 distinct operating conditions while varying the lubrication condition (unlubricated, boric acid, canola oil, boric acid/canola oil mixture), boric acid volume fraction, and boric acid particle size. Based on the experiments, it was determined that a solid volume fraction of 7% with 350–700μm particles was the optimum green particulate lubricant candidate for minimizing the friction at the conditions tested. This work also uncovered an inverse relationship between the friction coefficient and boric acid particle size (in canola oil at 7% solid fraction). Micrographs of the pin and disk wear track were analyzed to study this frictional behavior of the interface materials. Additionally, rheological tests were conducted to measure the viscosity of the canola oil and boric acid powder mixture as a function of particle size, and it was found that the viscosity increased with particle size over the size range tested. Finally, the results indicated that the boric acid-canola oil lubricant mixture demonstrated excellent potential for use as lubricants in industrial applications such as sheet metal forming.

The selective removal of oil from wastewaters while minimizing concentrate production using a membrane cascade

This paper describes the results of a study aimed at removing oil and grease from bilge water accumulating in the lower recesses of ships. Bilge water is a difficult wastewater to treat as it contains seawater, particulates, used oils and detergents. The objective of this work was to design a membrane system that minimized the production of brine retentate waters that must be stored onboard a ship. A pilot scale membrane cascade system was designed and evaluated in this work using tubular MF and UF membranes in a first stage, where high levels of particulate matter are present, and Sepa® flow cells representing spiral wound modules in the second stage. Large channel MF and UF ceramic membranes were used in the first loop while a variety of flat sheet UF (1–100 kD MWCO) and NF membranes were studied in the second stage (loop 2). Permeates obtained from the first and second stages were analyzed using an extraction procedure followed by gas chromatography. It was found that lower MWCO membranes (1–5 kD) had excellent permeate fluxes ranging from 25 to 62 L/m 2/h and rejections rates of hexane extractable organics were above 90%. The hexane extractable oil and grease concentrations in the permeates from these membranes were found to be 0.1 and 0.0 ppm for the corresponding 1, and 2 kD MWCO membranes. The size of oil particles in the second loop was measured by dispersive light scattering (DLS). Nano sized particles were observed and the size of these particles was found to increase over time as a result of mixing and circulating in the second loop.

The Structure and Dynamics of Microparticles at Pickering Emulsion Interfaces

We have employed a laser scanning confocal microscope (LSCM) to study the structure and dynamics of microparticles at Pickering emulsion interfaces. The microparticles can have rich morphology at the emulsion interfaces, ranging from an aggregated structure to colloidal lattices, with a possibility of involving heterogeneous particles. With a specific interest in colloidal lattices, we find that although the enhanced electrostatic repulsion explains the formation of colloidal lattices by sulfate-treated polystyrene (S-PS) particles, it fails to interpret the unsuccessfulness of assembling lattices containing single-species carboxylate-treated polystyrene (C-PS) particles. A small percentage of C-PS particles in the colloidal mixture does not disturb the formation of lattices made of S-PS particles. The LSCM also provides a meaningful way to probe dynamic information. The diffusion of single particles at the emulsion interfaces depends strongly on the oil phase viscosity, particle size, and particle wettability. A highly curved emulsion interface slows the motion of microparticles at oil-water interfaces but the interface curvature effect decreases with increasing oil phase viscosity. Although the confocal microscope was originally used as an imaging tool, we find that the thermodynamic equilibrium of colloidal lattices can be disturbed and even destroyed when increasing the output laser intensity.

Thickening properties and emulsification mechanisms of new derivatives of polysaccharides in aqueous solution

The thickening properties of aqueous solutions of HHM-HEC (hydrophobically–hydrophilically modified hydroxyethylcellulose) and the emulsification mechanisms of HHM-HEC/water/oil systems were investigated. A dramatic increase in viscosity was observed with increased HHM-HEC concentration in water, caused by aggregation of hydrophobic alkyl chains. At higher concentrations of HHM-HEC (above 0.6 wt%) in water, it forms an elastic gel, which has good thixotropic properties and a high yield value. O/W (oil-in-water) type emulsions were obtained using HHM-HEC, which can emulsify various kinds of oil, including hydrocarbon, silicone, and perfluoropolymethylisopropyl ether. The viscosity of these emulsions depends only upon the oil volume fraction, not on the kind of oil. In addition, the oil particle size in the emulsions remained constant after a certain period because HHM-HEC formed a strong gel network structure and a protective layer, which prevented the emulsion from coalescing. Measurements of interfacial tension revealed that the alkyl chains in HHM-HEC did not significantly lower the interfacial tension at the water/oil interface when 0.5 wt% of HHM-HEC was added to water. Steady flow and oscillatory experimental results show that the rheological behavior of HHM-HEC/water/oil emulsions was similar to that of aqueous solutions of HHM-HEC. In the HHM-HEC/water/oil emulsion system, oil droplets were dispersed and kept stable in the strong gel structure of HHM-HEC. The aqueous solution of HHM-HEC showed salt resistance. It is thought to be due to sulfonic acid groups in HHM-HEC. The stability of the emulsion using HHM-HEC is based on both protective colloidal effects and associative thickening caused by alkyl chains in HHM-HEC.

Improved Peanut Flour for a Reduced‐Fat Peanut Butter Product

ABSTRACT A commercial peanut flour (12% fat) was mixed with water (30% w/w), homogenized and drum‐dried in a double drum dryer. The drum clearance was adjusted to result in thin dried sheets which on milling resulted in a very fine, single banded particle size flour. The flour was no longer gritty and was used to dilute fat by mixing with full fat (52.5%) paste to obtain a 30% fat reduction in the peanut butter product. Response surface methodology, RSM, was used to optimize drum temperature (T), speed (S), and clearance (C) in order to minimize stickiness and hardness, maximizing oil separation and particle size. Based on surface responses and contour plots, optimum conditions were: T = 135 °C, S = 1 rpm and C = 0.33 mm. Optimum values predicted by RSM for peanut flour particle size, peanut butter stickiness, hardness, and oil separation were: 49.65 μm, 12347 N, 311.4 N and 6.87% respectively. Close agreement between experimental and predicted values was obtained.

O/W Lipid Emulsions for Parenteral Drug Delivery. III. Lipophilicity Necessary for Incorporation in Oil Particles Even After Intravenous Injection

The potential usefulness of oil-in-water (O/W) lipid emulsions as injectable drug delivery systems was examined. Plasma concentrations of oil particles after intravenous injection of a standard lipid emulsion composed of soybean oil and egg yolk phosphatides were monitored based on the plasma concentrations of phospholipids and triglycerides, and the light scattering intensity of the plasma. Their time profiles were similar to each other, and the oil particle size decreased time-dependently. Pretreatment with dextran sulfate, a known reticuloendothelial system (RES) suppressor, resulted in marked reduction of the plasma clearance of the oil particles and of the time-dependent alteration of oil particle size, suggesting that oil particles were trapped by RES. The lipophilicity of the drug needed for its incorporation in the oil particles even after intravenous injection was found to be clog P > 8, where clog P is the calculated logarithm of the partition coefficient between n-octanol and water. In the case of Sudan II (clog P = 5.4), the release from the oil particles was very quick after intravenous injection, resulting in slight alteration in biodistribution when compared with its micellar solution. In contrast, menatetrenone (clog P = 9.5) was selectively delivered to the liver, lungs and spleen, being consistent with the oil particles taken up by RES.

Effect of Composition on Biological Fate of Oil Particles after Intravenous Injection of O/W Lipid Emulsions

Plasma concentrations of oil particles after intravenous injection of oil-in-water (O/W) lipid emulsions were monitored based on the plasma concentration of phospholipids (PL) and triglycerides (TG), and the light scattering intensity (LSI) of plasma. Previously, we found that their time profiles after injection of the standard O/W lipid emulsion composed of soybean oil (SO) and egg yolk phosphatides (EYP) were similar and suggested that the oil particles with diameter of about 200 nm were entrapped by reticuloendothelial system (RES). Herein, in order to develop a delivery system to avoid the RES uptake by using the lipid emulsions, biological fate of lipid emulsions with oil particles of various sizes or those emulsified by surfactants with polyoxyethylene segments were subjected to the investigations.Lipid emulsions with oil particles of various sizes (about 150-550 nm) were prepared by altering EYP content. The oil particles were stable in plasma in vitro, but oil particle size decreased time-dependently after intravenous injection. Plasma clearance of oil particles depended on their initial size and was decreased by pretreatment with dextran sulfate 500 (DS500), a known RES suppressor. These results suggested that oil particles are still entrapped by RES, even for small-sized oil particles (about 150nm). Lipid emulsion with small-sized oil particles was also prepared using medium chain triglycerides. The oil particles were stable in vitro, but the time profiles of plasma concentrations of PL and TG, and LSI of plasma were different, and oil particle size decreased time-dependently after intravenous injection. Plasma clearance of the oil particles also depended on their initial size and was decreased by DS500, suggesting that in vivo instability could be due to RES-mediated processes. Artificial surfactants with polyoxyethylene segments, HCO-60 (HCO60) and polysorbate 80 (PS80), were used for RES avoidance. HCO60 resulted in drastic reduction of the plasma clearance of the oil particles for both lipid emulsions composed of soybean oil and medium chain triglycerides. The time-dependent decrease of oil particle size after intravenous injection was marginal. In contrast, PS80 could not prolong the circulation time of the oil particles, and their size decreased time-dependently after intravenous injection.