Reference Oil Research Articles

In-line measurements of the physical and thermodynamic properties of single and multicomponent liquids.

Microfluidic devices are becoming increasingly important in various fields of pharmacy, flow chemistry and healthcare. In the embedded microchannel, the flow rates, the dynamic viscosity of the transported liquids and the fluid dynamic properties play an important role. Various functional auxiliary components of microfluidic devices such as flow restrictors, valves and flow meters need to be characterised with liquids used in several microfluidic applications. However, calibration with water does not always reflect the behaviour of the liquids used inthe different applications. Therefore, several National Metrology Institutes (NMI) have developed micro-pipe viscometers for traceable inline measurement of the dynamic viscosity of liquids used in flow applications aspart of the EMPIR 18HLT08 MeDDII project. These micro-pipe viscometers allow the calibration of any flow device at different flow rates and the calibration of the dynamic viscosity of the liquid or liquid mixture used under actual flow conditions. The validation of the micro-pipe viscometers has been performed either with traceable reference oils or with different liquids typically administered in hospitals, such as saline and/or glucose solutions or even glycerol-water mixtures for higher dynamic viscosities. Furthermore, measurement results ofa commercially available device and a technology demonstrator for the inline measurement of dynamic viscosity and density are presented in this paper.

Tar ball pollution under the influence of ocean circulation in the Bohai Sea, China

The deposition of tar balls of unknown sources on the coast poses a great threat to the fishery, tourism and coastal biodiversity in the Bohai Sea. This work aimed to identify the sources of tar balls by using oil fingerprint technique. Tar ball samples were collected from the seashore of two islands of the western Bohai Sea and divided into two groups (Group I and Group II). Principal component analysis showed that although Caofeidian oilfield was one of the closest oilfields to the sampling area it was not a source. Fingerprints of characteristic hopanes and steranes showed that samples of Group I were similar to the crude oils from the nearby Jidong oilfield, and samples of Group II were similar to the Penglai-19-3 crude oils. Combined with cross-plots of the samples and the reference oils, it indicated that Group I may come from Jidong and Group II may come from Penglai-19-3. The weathering characteristics of alkanes and polycyclic aromatic hydrocarbons showed that the samples were affected by natural weathering processes (e.g., evaporation, photooxidation and biodegradation). It revealed that oil pollution from the nearby oilfields can also affect other areas under the influence of ocean circulation. It is the first study on source identification of tar balls from the Bohai Sea and the effects of ocean circulation on the tar ball transport. This study can considerably help to further understand the evolution of tar balls and consequently determine their sources.

Evaluation of Micro-Distillation Methodology in Obtaining the Oil Distillation Curve Using Design of Experiments

In the evaluation of petroleum, the true boiling point (TBP) curve stands out among the characterization analyzes, as it is fundamental to assist in decision making such as pricing, royalty payment and petroleum valuation. This is possible by defining the yields of petroleum derivatives obtained as a function of their true boiling points. Its obtainment can partially conducted by applying the ASTM D2892 methodology, for fractions with temperatures up to 673 kelvin. Requiring a minimum volume of 1200 mL of oil and an average time of 48 hours. The present work aims to evaluate the feasibility of applying micro-distillation in the construction of the TBP curve, with volume and time reduction using reference oil. For this, established experiments will conducted according to the application of experiment planning and their results will compared with the curve obtained under standard conditions by ASTM D2892. The variables studied were distillation column size, heating rate control and magnetic bar shape. As a result, two conditions provided adjustment to the validation curve across the entire length of the conventional TBP ASTM curve, with the possibility of using columns of different sizes, minimum sample volume of 700 mL and reduction of total time to 16 hours and 40 minutes.

Detailed characterization of aeration in lubricating oils by an ultrasonic approach

Lubricating oils get aerated during their use, reducing their efficiency and stability. Deaerating agents are generally added to reduce aeration. Understanding the mechanisms by which these additives set the gas fraction in oil is crucial for the development of optimal formulation. Here we present experiments performed on a Flender test apparatus in which ultrasonic probes are incorporated. We present the technique and demonstrate that it provides the gas volume fraction but also information on the bubble size during the aeration process. Thanks to this measuring technique, new insights on the dynamics of both aeration and de-aeration are gained. As an example, we show how these parameters are affected by the presence of four different additives in a specific reference oil.

Amide polymers based on N‐phenyl‐p‐phenylenediamine with α‐olefins‐co‐maleic anhydride as multifunctional additives for lubricant application

AbstractThe high temperature and harsh oxidizing conditions in engine sump results in sludge and varnish deposits in the engine, due to which wear debris and corrosion developed in the internal parts of the engine. This is also responsible for the increased oil viscosity. To address these problems, four polymeric multifunctional amides of N‐phenyl‐p‐phenylenediamine were synthesized from copolymer intermediates poly(α‐olefins‐co‐maleic anhydride) having C‐12, C‐14, C‐16, and C‐18 chain length. This article describes the systematic study of poly(α‐olefin‐co‐maleic anhydride)amides chemistry as multifunctional lubricant additives. Molecular elucidation was carried out by Fourier transform infrared and nuclear magnetic resonance while molecular weight and thermal stability were measured by gel permeation chromatography and thermogravimetric analysis. Standard methods were used to analyze the viscosity‐temperature relationship along with detergent‐dispersant, anti‐oxidant, and anti‐corrosion activities in reference base oil at varying concentration levels. All the prepared polymer compounds effectively addressed the concern problems, but poly(octadecene‐co‐maleic anhydride)amide of N‐phenyl‐p‐phenylenediamine showed better performance over the other additives due to the increased solubility. The pour point depressed from the base value −15 to −30°C while viscosity index (VI) increased to 197 from 178 with longer chain additive at 5000 ppm concentration. Dispersancy was found to be increased by 145%, while as far detergency was concerned, sludge deposition was reduced to 20.1 mg from 87.5 mg base value of reference base oil at 5000 ppm. 2,2‐diphenyl‐1‐picrylhydrazyl assay was used to determine the anti‐oxidant activity and at 1000 ppm, long alkylated polymer shows the excellent result by increasing the inhibition efficiency by 95.58% while the same additive impart the best results at 5000 ppm by reducing the corrosion and penetration rate by 75.80% and 75.43% respectively. Rheology also studied to examine the shear and temperature effect on the dynamic viscosity of the reference oil.

A Study on Decisive Early Stages in White Etching Crack Formation Induced by Lubrication

The reliability of rolling bearings is affected by white etching crack (WEC) or white structure flaking (WSF) failures, causing tremendous commercial burdens for bearing manufacturers and operators. The research for the underlying failure mechanism has attracted interest from a large scientific community over decades. Despite the significant amount of efforts, a root cause of white etching cracking is still missing. Amongst other factors, lubricant chemistry is considered to be essential in WEC formation. The authors aim to elucidate this key parameter by provoking white etching crack formation on a FE8 bearing test rig using a well-described set of chemicals in high- and low-reference lubricants. Scanning electron microscopy and energy dispersive X-ray analysis prove the presence of a patchy tribofilm on the surface of bearing washers, leading most likely to a higher frictional torque at the early stages of operation when the low reference oil is used. Secondary neutral mass spectrometry (SNMS) shows a hydrogen containing tribofilm in the shallow subsurface of about 30 nm depth, suggesting that hydrogen proliferating into bearing material may subsequently facilitate crack propagation via dislocation pileups, leading to premature bearing failure.

Exploring Lignans, a Class of Health Promoting Compounds, in a Variety of Edible Oils from Brazil.

Lignans, a group of polyphenols, have been identified in eight cold pressed oils from fruits, nuts, and seeds, retrieved from the Brazilian market. The oils under investigation were avocado, Brazilian nut, canola, coconut, grapeseed, macadamia, palm, and pequi. Olive oil was selected as a reference oil, since numerous data on its lignan content are available in literature. The qualitative and quantitative profiles were obtained, after extraction, by means of UFLC-ESI-MS/MS analyses. The total lignan content showed a high variability, ranging from 0.69 mg·Kg−1 (pequi) to 7.12 mg·Kg−1 (grapeseed), with the highest content registered for olive oil. Seven lignans were quantified, matairesinol and pinoresinol being the most abundant. The LC-MS/MS method was validated, showing linearity in the range of 12.5–212.5 mg·Kg−1, LOD in the range of 0.18–11.37 mg·Kg−1, and LOQ in the range of 0.53–34.45 mg·Kg−1. Additionally, part of the study was focused on the evaluation of the flavor profile, this being a key element in consumers’ evaluations, by means of HS-SPME-GC. In total, 150 volatile compounds were determined in the eight oils, with identified fractions ranging from 91.85% (avocado) to 96.31% (canola), with an average value of 94.1%. Groups of components contributed characteristically to the flavour of each oil.

A hybrid concentrated solar/biomass combustion system with internal thermal energy storage for fully dispatchable renewable electricity production in Mauritius

AbstractWind and solar photovoltaic need expensive battery energy storage for dispatchability. Concentrated solar power plus internal thermal energy storage permits dispatchability, but it is convenient only in areas of large direct normal irradiance. A hybrid concentrated solar/combustion system is proposed for Mauritius, an area of modest direct normal irradiance, and biomass availability. The small, modular, 8 kW system for microgrid application comprises a beam down point concentrator, two tanks of molten salt thermal energy storage, a biomass combustion heater, a Stirling engine, and a generator. The hybrid system has a thermal energy supply solar of 41%, and a thermal energy supply by combustion fuel 59%. By assuming a zero CO2e emission for solar thermal energy supply (100% reduction of CO2e) and a 21% CO2e emission for thermal energy from the combustion of bagasse (79% reduction) vs thermal energy from oil combustion, the proposed hybrid device would permit an 88% reduction of the emission of CO2 vs the reference oil combustion plant.

Research on quality evaluation of lubricating oil based on China’s independent development

At present, China has become the largest automobile production and sales country in the world, and the second largest lubricant consumption country. It is of great significance to establish China’s independent certification and evaluation system for lubricants.In recent years, China’s heavy-duty diesel engine has basically realized the technology autonomy, and the mode of lubricant evaluation standard equivalent to API specification is not suitable for China’s national conditions. It is imperative to develop a diesel engine oil quality evaluation research that is suitable for China’s national conditions. This paper mainly introduces a series of research on the performance difference of JAC 2.0TCI engine based on the physicochemical, wear and sediment evaluation of different reference oils under the condition of fuel dilution.

The effect of anion architecture on the lubrication chemistry of phosphonium orthoborate ionic liquids

Phosphonium ionic liquids with orthoborate anions have been studied in terms of their interfacial film formation, both physisorbed and sacrificial from chemical breakdown, in sheared contacts of varying harshness. The halogen-free anion architecture was varied through (i) the heteronuclear ring size, (ii) the hybridisation of the constituent atoms, and (iii) the addition of aryl functionalities. Time of Flight-Secondary Ion Mass Spectrometry analysis revealed the extent of sacrificial tribofilm formation allowing the relative stability of the ionic liquids under tribological conditions to be determined and their breakdown mechanisms to be compared to simple thermal decomposition. Overall, ionic liquids outperformed reference oils as lubricants; in some cases, sacrificial films were formed (with anion breakdown a necessary precursor to phosphonium cation decomposition) while in other cases, a protective, self-assembly lubricant layer or hybrid film was formed. The salicylate-based anion was the most chemically stable and decomposed only slightly even under the harshest conditions. It was further found that surface topography influenced the degree of breakdown through enhanced material transport and replenishment. This work thus unveils the relationship between ionic liquid composition and structure, and the ensuing inter- and intra-molecular interactions and chemical stability, and demonstrates the intrinsic tuneability of an ionic liquid lubrication technology.

Preliminary Characterisation of Wastes Generated from the Rapeseed and Sunflower Protein Isolation Process and Their Valorisation in Delaying Oil Oxidation

Since rapeseed and sunflower meals are two of the most representative oilseed crops in the world, this study was focused on ethanol-wash solutes (EWS) obtained as wastes from the protein isolation process of rapeseed and sunflower meals. These meals have been previously valorised; however, the use of the EWS is unexplored. The present study is aimed at the characterisation of their phenolic profile, and antioxidant capacity for preventing lipid oxidation in rapeseed, sunflower, and soybean oil, which has been used as a reference oil. The sunflower EWS exhibited more total phenolic compounds (TPC) and antioxidant activity (119.39 ± 1.13 mg GA/g and 193.97 ± 9.77 mg TE/g, respectively) than the rapeseed one (103.44 ± 5.94 mg GA/g and 89.51 ± 3.17 mg TE/g). The phenolic identification showed hydroxybenzoic and protocatechuic acid in the rapeseed EWS, and pyrogallol and caffeic acid in the sunflower EWS, as the main representative phenols. Both EWS at 15% increased significantly (p < 0.05) the oxidative stability of the oils in the Rancimat equipment with values of antioxidant activity index (AAI) from 1.01 to 1.20, depending on the type of oil employed. In conclusion, the rapeseed and sunflower EWS showed great potential, and they could be used as a source of natural antioxidants within the food industry, replacing the synthetic ones, and promoting the circular economy since they are agro-food wastes.

Palmitic acid–rich oils with and without interesterification lower postprandial lipemia and increase atherogenic lipoproteins compared with a MUFA-rich oil: A randomized controlled trial

ABSTRACTBackgroundInteresterified (IE) fats are widely used in place of trans fats; however, little is known about their metabolism.ObjectivesTo test the impact of a commonly consumed IE compared with a non-IE equivalent fat on in vivo postprandial and in vitro lipid metabolism, compared with a reference oil [rapeseed oil (RO)].MethodsA double-blinded, 3-phase crossover, randomized controlled trial was performed in healthy adults (n = 20) aged 45–75 y. Postprandial plasma triacylglycerol and lipoprotein responses (including stable isotope tracing) to a test meal (50 g fat) were evaluated over 8 h. The test fats were IE 80:20 palm stearin/palm kernel fat, an identical non-IE fat, and RO (control). In vitro, mechanisms of digestion were explored using a dynamic gastric model (DGM).ResultsPlasma triacylglycerol 8-h incremental area under the curves were lower following non-IE compared with RO [–1.7 mmol/L⋅h (95% CI: –3.3, –0.0)], but there were no differences between IE and RO or IE and non-IE. LDL particles were smaller following IE and non-IE compared with RO (P = 0.005). Extra extra large, extra large, and large VLDL particle concentrations were higher following IE and non-IE compared with RO at 6–8 h (P < 0.05). No differences in the appearance of [13C]palmitic acid in plasma triacylglycerol were observed between IE and non-IE fats. DGM revealed differences in phase separation of the IE and non-IE meals and delayed release of SFAs compared with RO.ConclusionsInteresterification did not modify fat digestion, postprandial lipemia, or lipid metabolism measured by stable isotope and DGM analysis. Despite the lower lipemia following the SFA-rich fats, increased proatherogenic large triacylglycerol-rich lipoprotein remnant and small LDL particles following the SFA-rich fats relative to RO adds a new postprandial dimension to the mechanistic evidence linking SFAs to cardiovascular disease risk.

Migration of mineral oil in elastomers

This work describes a newly introduced experimental procedure to quantify the diffusion progress of mineral oils locally resolved in NBR. Diffusion of reference oils IRM 901, IRM 902 and IRM 903 in NBR with various acrylonitrile contents was investigated. Classical sorption experiments were performed as a basic characterization and compared to the newly introduced method. Here, elastomer specimens are only being dipped with the bottom in a relatively small reservoir of mineral oil. This provides a determination of locally resolved concentration profiles of mineral oils, and the calculation of diffusion coefficients. These diffusion coefficients follow the same trends like those determined via sorption experiments. Despite differences in the absolute numbers, activation energies of diffusion can be applied as a suitable measure for the compatibility of elastomers and fluids.

Ultrasound-assisted lipid extractions, enriched with sterols and tetranortriterpenoids, from Carapa guianensis seeds and the application of lipidomics using GC/MS.

This study describes the optimized stages of lipid extraction assisted by ultrasound to increase the concentrations of limonoids and steroids from andiroba seeds, identified as Carapa guianensis Aublet, and the lipidome analyzed by TLC and GC/MS. After boiling and peeling, crushed seeds were subjected to extractions with n-hexane (G1), acetone (G2), and methanol (G3) in an ultrasonic bath for 30 minutes at 50 °C. These extracts were analyzed by analytical TLC; aliquots of each extract and a marketable oil, used as a reference, were transesterified followed by silylation with BSTFA + 1% TMCS, and analyzed by GC/MS. The reference oil and the biomass of the seeds did not present significant differences in the profiles of free fatty acids (FFA). However, differences were observed in the profiles of tetranortriterpenoids (TnTT) (limonoids) in the seeds. Afterward, the analysis of the extracts G1, G2, and G3 detected free steroids: campesterol, stigmasterol, and β-sitosterol; and limonoids: 7-deacetyl-7-oxogedunin, 6α-acetoxy-gedunin, deacetylgedunin, and epoxyacetylgedunin. The use of lipidomic techniques associated with ultrasound-assisted extraction was applied for the first time to enhance the triterpenoids and steroids, mainly in G3, describing a faster and more economical process, and allowing a one-step lipidome analysis of the andiroba seeds.

Performance of castor based biodiesel during tribological characterization at different load

In this study, friction and wear analysis of castor oil-based biodiesel was conducted. The B0, B100, B10, B20 and B50 are the samples considered for the test. The test was performed on pin-on-disc machine at different loads 40 N and 100 N. The sliding speed of 150 rpm was considered constant and ambient temperature was taken during the analysis. It has been observed that the coefficient of friction increases with the applied load. The diesel was taken as the reference oil. The diesel (B0) shows more coefficient of friction and wear at both the loads. The minimum coefficient of friction and less wear of the surface was obtained at 100% biodiesel (B100). The increment of biodiesel blends showed better results in reducing friction, and wear of the parts during their sliding contact. Biodiesel is having better lubricity as compared to diesel and could be implemented in the diesel engine as a lubricant in near future.

1H NMR Spectroscopy to Characterize Italian Extra Virgin Olive Oil Blends, Using Statistical Models and Databases Based on Monocultivar Reference Oils.

During the last few years, the global demand for extra virgin olive oil (EVOO) is increased. Olive oil represents a significant percentage of world fat consumption determining an important development of its market. In this context, the problems related to counterfeiting and product fraud is becoming extremely relevant. Thus, the quality and authenticity control of EVOOs is nowadays mandatory. In this study we focused on the use of 1H NMR technique associated with multivariate statistical analysis to characterize Italian EVOOs commercial blends. In particular, a specific database including 126 monocultivar EVOOs reference samples, was used to characterize a total of 241 Italian EVOOs blends over four consecutive harvesting years. Moreover, the effect of the minor components (phenolic compounds) on the qualitative characterization of blended EVOOs was also evaluated. The correlation analysis of classification scores obtained using two pairwise orthogonal partial least square-discriminant analysis models (built with major and combined major–minor components NMR data) revealed that both could be profitably used to generally classify the studied Coratina containing blends.

A rapid RNA extraction method from oil palm tissues suitable for reverse transcription quantitative real-time PCR (RT-qPCR).

Cetyltrimethylammonium bromide (CTAB) is the preferred detergent in RNA extraction of oil palm tissues. However, the CTAB-based protocol is time-consuming. In this study, a combination of the CTAB-based method and silica-based purification reduced the extraction time from two days to five hours. Quality of total RNA from 27 different tissues of oil palm was shown to have an RNA integrity number (RIN) value of more than seven. The extracted RNA was evaluated by RT-qPCR using three reference oil palm genes (GRAS, CYP2, and SLU7) and three putative mesocarp-specific transcripts annotated as WRKY DNA-binding protein 70 (WRKY-70), metallothionein (MT) and pentatricopeptide repeat (PPR) genes. Tissue-specific expression profiling across complete developmental stages of mesocarp and vegetative tissues was determined in this study. Overall, the RNA extraction protocol described here is rapid, simple and yields good quality RNAs from oil palm tissues.

Tribology performance analysis of oil for wet drive axle

In order to solve the problems caused by the use of common gear oil in the wet drive axle, such as abnormal braking noise, excessive braking distance and severe wear of components, the special oil for the wet drive axle is developed in accordance with the new requirements for lubricating oil after the technical upgrade of the drive axle. Based on the actual braking condition of the wet brake, the oil tribology performance of the wet drive axle is tested and studied by using the brake test bench and increasing the energy density to improve the harshness of the braking condition. The results show that the method can distinguish oil with different tribology performance. The developed oil is superior to the reference oil in formulating smoothness, stability and mechanical transmission efficiency, providing better friction retention over long periods of use.

Preparation and quality evaluation of a volatile oil microemulsion from Flos magnoliae and Centipeda minima.

In order to improve the water solubility of the volatile oils extracted from Flos magnoliae (FM) and Centipeda minima (CM), they were prepared as a microemulsion (ME), which were then used in the development of an FM and CM volatile oil ME for the treatment of allergic rhinitis (AR). ME was prepared by phase inversion emulsification, and the prescription factors such as emulsifier, co-emulsifier, oil phase, Km, which represents the ratio of the mass of emulsifier to that of the co-emulsifier, and preparation factors such as temperature affecting the formation of the ME were selected according to the formation area of ME in a pseudo-ternary phase diagram. The quality of the ME was evaluated based on its appearance, particle size, Zeta potential and stability. The content of eucalyptol in ME was determined by gas chromatography-mass spectrometry (GC-MS). The cumulative permeability of the ME within 24 h was measured with a transdermal diffusion tester. The results revealed that the best formula for preparation of the ME was as follows: Castor oil polyoxyethylene ether (EL-40) was the emulsifier; the co-emulsifier was anhydrous ethanol; the Km was 2:1; the mixed phase of volatile oil and isopropyl myristate with mass ratio of 1:1 was used as oil phase; and the preparation temperature was 25°C. The content of eucalyptol in the ME was 2.57 mg/g, and the cumulative permeability of the ME in 24 h was significantly increased compared with that of the reference oil solution. The appearance of the ME was uniform, and the solution was transparent. In conclusion, compared with traditional preparations, FM and CM volatile oil ME is a novel, improved and more effective preparation for the treatment of AR.

Assessment of the potential of combining wave and solar energy resources to power supply worldwide offshore oil and gas platforms

Offshore oil and gas platforms have very high-power demands that are usually met locally by using gas turbines. Nowadays, the industry is seeking for environmentally friendly alternatives to power supply those facilities, such as by means of marine renewable energy. Motivated by economic and environmental aspects, this paper addresses the value proposition and investigates the feasibility of implementing combined wave and solar systems for power supplying offshore oil and gas platforms. Three locations where relevant offshore petroleum activities are currently ongoing were selected as case studies and a reference oil and gas platform was assumed. At each case study location, four wave energy converters and one photovoltaic technology were analysed for three scenarios: wave power only, solar power only and both resources combined. The methodology applied, generalizable to other regions with petroleum activities and relevant wave and solar energy resources, consists in scaling the wave energy converters to match wave climate at site, maximizing their energy production, followed by an economic feasibility analysis. Results show that for all sites the combination of both renewable resources increases electricity production, reduces the intra-annual variability of energy production and intermittency issues, increases capacity factors up to 24% and consequently avoids overdesign. The obtained levelized cost of energy is in the range 131–263 €/MWh and the reduction in emissions was estimated at circa 281,915 ton/year at each site, which demonstrates the feasibility and interest of providing electricity from these combined systems to offshore oil and gas platforms. The proposed solution provides benefits that could lead to further decreases in the levelized cost of energy, enabling the entrance to new markets for both wave and solar energy, while facilitating the transition to a more sustainable energy mix. Hence, the further technology development is advocated.