Canola protein thermal denaturation improved emulsion-templated oleogelation and its cake-baking application

The stability and viscoelasticity of an oil-in-water emulsion formed with canola proteins could be significantly improved by heat-induced protein thermal denaturation followed by aggregation at the oil droplet surface. This phenomenon was used to develop emulsion-templated oleogels with improved rheology and used in cake baking. Canola oil (50 wt%)-in-water emulsions stabilized by 1 and 4 wt% canola protein isolates (CPI), prepared by high-pressure homogenization, were dried at 60 °C in a vacuum oven followed by shearing to create the oleogels. Before drying, the emulsions were heated (90 °C for 30 min) to induce protein denaturation. The oleogel from 4 wt% CPI heated emulsions (HE) exhibited the lowest oil loss, highest gel strength, firmness and stickiness compared to all other oleogels. Cake batter prepared with shortening showed the lowest specific gravity, highest viscosity and storage modulus compared to CPI oleogels. Confocal micrographs of shortening cake batters showed smaller air bubbles entrapped in the continuous fat phase. In comparison, the oleogel cake batters showed dispersion of larger air bubbles, oil droplets, and protein aggregates. The oleogel cake showed a darker colour compared to the shortening cake due to the dark colour of CPI. Interestingly, oleogel cakes showed lower hardness, higher cohesiveness and springiness than the shortening cake, which was attributed to the higher cake volume of the former due to the formation of larger air channels stabilized by canola proteins. In conclusion, CPI stabilized emulsion-templated oleogels could be used as a potential shortening replacer in cake and other baking applications.

The stability and viscoelasticity of an oil-in-water emulsion formed with canola proteins could be significantly improved by heat-induced protein thermal denaturation followed by aggregation at the oil droplet surface.     

Long-term stably dispersed functionalized graphene oxide as an oil additive

In oil lubrication systems, it is essential to continuously supply lubricant to the contact surface during practical applications. Herein, to realize its long-term stable dispersion in oil, graphene oxide was modified with polyisobutylene succinimide (PIBS, trade name T154), which is an effective dispersant for lubricating oils. Characterization of the T154-modified graphene oxide (GO-T154) by FTIR, XPS, and XRD revealed that the surface of the graphene platelets was covered by the T154 chains, and the dimensions of the graphene platelets had obviously decreased. The dispersion study demonstrated the long-term stability of a GO-T154/oil suspension, which could stand for more than a year without any significant precipitation. The lubricating property was greatly improved by the addition of GO-T154; more specifically, for the optimal performance, the friction coefficient decreased by 54%, and the wear rate decreased by 60%. Micro observation of the worn surfaces indicated that well-dispersed GO-T154 could enter the gap between the friction surfaces, forming a transfer film to separate the rubbing surface. With the long-term stability, high thermal stability and outstanding tribological properties of the suspension, GO-T154 promises to realize practical applications of graphene in lubricating oil.

T154 modified graphene oxide as an oil additive exhibited excellent tribological properties, long-term stable dispersity and high thermal properties.     

Engineering phytosterol-based oleogels for potential application as sustainable petrolatum replacement

Phytosterol-based oleogels have been engineered in edible oils for potential applications as sustainable replacements for petrolatum. Oleogels have emerged with a crystal network structure with oil molecules trapped inside. In addition, the viscosity of highly thixotropic oleogels could be tuned by manipulating the concentration of phytosterols and monoglycerides, and the type of surface-active small molecules and bulk vegetable oils. Furthermore, viscous soft matter could also be tunably made with 8–20% oleogelators in olive oil with favourable water vapour occlusive and wettability properties, in addition to having good texture, and outstanding thixotropic and thermal reversibility properties. These properties are quite similar to those of commercial petrolatum. This work demonstrates that the natural phytosterol-oleogels in edible oils can be a novel source of sustainable and green replacements for petrolatum.

Phytosterols, as a family of plant-produced molecules, are recognized for their natural health benefits. Phytosterol-based oleogels have been engineered in edible oils to be potential applicable as sustainable petrolatum replacements.     

Efficient tribological properties of azomethine-functionalized chitosan as a bio-lubricant additive in paraffin oil: experimental and theoretical analysis

A simple condensation of chitosan (from shrimp shells) and 4-hydroxybenzaldehyde was performed to yield bio-lubricant additive comprised of azomethine functional groups to be used with paraffin lube oil in industries. The synthesized Schiff base derivative of chitosan (SBC) additive was characterized using a CHN analyzer and FT-IR spectroscopy, and the thermal stability was explored using thermogravimetry. The rheological properties of SBC additives in paraffin oil were studied and are discussed herein. The tribological properties of SBC were tested in paraffin as the base oil employing a four-ball tester with different experimental conditions (viz. the concentration of the additive, applied load, speed and time duration), following ASTM D4172A standards. The optimum concentration of the additive in the base oil was found to be 150 ppm, exhibiting minimum coefficient of friction, but with higher concentrations of additive in base oils, the coefficient of friction increased. UV-Vis spectroscopy studies were also performed to confirm the formation of SBC and dispersion stability. The determined tribological parameters, such as the coefficient of friction, mean wear scar diameters and mean wear scar volumes, were found to significantly reduce the coefficient of friction of paraffin oil upon the addition of SBC. The state of steel balls upon exposure to various experimental conditions was analyzed and explained based on outcomes from FESEM, EDX, ferrography and AFM spectroscopy. The insights into interactions of the synthesized SBC with the metal surface were explored using ab initio density functional theory, Fukui indices, molecular dynamics simulation and radial distribution function.

Schiff base derivative of chitosan as biolubricant additive explored in paraffin lube oil.     

Screening of highly effective mixed natural antioxidants to improve the oxidative stability of microalgal DHA-rich oil

Docosahexaenoic acid (DHA)-rich oil sourced from microalgae can easily become oxidized. The objective of this work was to screen the optimal natural antioxidant mixture for protecting DHA-rich oil. Different natural antioxidants, encompassing tea polyphenols, natural vitamin E, rosemary extract, licorice root antioxidant, ascorbyl palmitate and lecithin were tested individually and in combination in an accelerated oxidation process. Three antioxidants namely natural vitamin E, rosemary extract and ascorbyl palmitate with synergistic effects were chosen, and their concentrations were further optimized using response-surface methodology. The highest antioxidants activity of 16.1740 was obtained with a combination of 0.0224% vitamin E, 0.0259% rosemary extract and 0.0166% ascorbyl palmitate, which prolonged the time until oxidation induction to 20.21 days. The mixed natural antioxidants showed a similar antioxidant effect to 0.02% tert-butylhydroquinone and was better than 0.02% butylated hydroxyanisole. These data indicate that the mixed natural antioxidants optimized in this work can be directly applied in the protection of commercial microalgal DHA-rich oil.

Antioxidants with synergistic effect were screened and optimized by RSM. The final natural antioxidant mixture can be actually applied in micrialgal DHA-rich oil, helping to enhance the antioxidant ability of DHA oil and extend its shelf life.     

Analytical methods for the determination of oil carryover from CNG/biomethane refueling stations recovered in a solvent

Vehicle gas is often compressed to about 200 bar at the refueling station prior to charging to the vehicle''s tank. If a high amount of oil is carried over to the gas, it may cause damage to the vehicles; it is therefore necessary to accurately measure oil carryover. In this paper, three analytical methods for accurate quantification of the oil content are presented whereby two methods are based on gas chromatography and one on FTIR. To better evaluate the level of complexity of the matrix, 10 different compressor oils in use at different refueling stations were initially collected and analysed with GC and FTIR to identify their analytical traces. The GC traces could be divided into three different profiles: oils exhibiting some well resolved peaks, oils exhibiting globally unresolved peaks with some dominant peaks on top of the hump and oils exhibiting globally unresolved peaks. After selection of three oils; one oil from each type, the three methods were evaluated with regards to the detection and quantification limits, the working range, precision, trueness and robustness. The evaluation of the three measurement methods demonstrated that any of these three methods presented were suitable for the quantification of compressor oil for samples. The FTIR method and the GC/MS method both resulted in measurement uncertainties close to 20% rel. while the GC/FID method resulted in a higher measurement uncertainty (U = 30% rel.).

Vehicle gas is often compressed to about 200 bar at the refueling station prior to charging to the vehicle''s tank.     

Corrosion resistance for superwetting immiscible oil/water separation porous materials

In this paper, we first fabricate a 3D porous FZCF (FAS-modified ZnO-grown copper foam) with robust superhydrophobicity in air and superoleophilicity under water and the repeatable superwettability, and then mainly explore and analyze its corrosion resistance. The superhydrophobic–superoleophilic FZCF as an immiscible oil/organic solvent separation material shows high adsorption capacity and separation efficiency due to its heterogeneous micro–nano structures and low surface energy. It has excellent corrosion resistance under various pH conditions, and can serve as a corrosion protective barrier that prevents metal from contacting corrosive seawater in marine applications. Adsorbed oils also make superoleophilic FZCF keep its durability and stability after suffering attack in strong acid and alkali environments for a long time. Superwetting porous FZCF material that possesses outstanding excellent corrosion resistance demonstrates potential applications in many industrial fields such as oily wastewater treatment and marine oil spill accidents.

Superwetting porous FZCF as immiscible oil/organic solvents separation material that possesses excellent corrosion resistance can be widely applied in many industrial fields such as oily wastewater treatment and marine oil spill accidents.     

Converting waste textiles into highly effective sorbent materials

Activated carbon fibres with a tubular structure and exfoliated surface were produced utilizing cotton textile waste as the precursor. The synthesized carbon fibres were freeze dried resulting in a tubular structure and large pore size distribution. The absorption properties against various oils and organic solvents were accessed, these fibres showed some of the highest absorption capabilities reported for cellulose based carbons, in particular for olive oil, gasoline and chloroform.

Activated carbon fibres with a tubular structure and exfoliated surface were produced utilizing cotton textile waste as the precursor.     

Synthesis of highly stable γ-Fe2O3 ferrofluid dispersed in liquid paraffin,motor oil and sunflower oil for heat transfer applications

This article aims at the synthesis of highly stable γ-Fe₂O₃ magnetic nanoparticles and their ferrofluids using different base liquids such as liquid paraffin, motor oil and sunflower oil for heat transfer applications. Phase and morphology of the synthesized nanoparticles were probed using XRD, SEM and FTIR spectroscopy. The average nanoparticle size of γ-Fe₂O₃ magnetic nanoparticles was found to be 13 nm. Stability of the ferrofluids was monitored by visually observing the aggregation nature of the nanoparticles for 180 days. The ferrofluid prepared using motor oil as a base fluid exhibited high stability (for more than 1 year) and a mean enhancement of 77% in thermal conductivity at 1.5 vol% nanoparticles was observed as compared to base fluid. The viscosity of the ferrofluids was also measured and found to be 18, 38 and 8 cP at 27 °C for the liquid paraffin based, motor oil based and sunflower oil based ferrofluid, respectively.

Highly stable ferrofluid for greater enhancement of thermal conductivity.     

Facile fabrication of long-chain alkyl functionalized ultrafine reduced graphene oxide nanocomposites for enhanced tribological performance

Due to their ultrathin 2D laminated structure as well as excellent mechanical and thermal stabilities, ultrafine graphene-based nanoparticles exhibit fascinating advantages as highly-efficient lubricant additives. However, it remains a daunting challenge to achieve good and durable dispersion of these graphene-based nanoparticles in lubricating oils. Herein, we report a facile and efficient integration strategy involving particle size miniaturization, surface grafting with octadecyl alcohol (OA), and partial chemical reduction to prepare a novel long-chain alkyl functionalized ultrafine reduced graphene oxide (RGO-g-OA) with highly-dispersive capacity and superior tribological performance. The chemical composition and structural characteristics, microstructural morphology, and particle size distribution of RGO-g-OA were systematically investigated. Combining significantly improved lipophilicity derived from the long-chain alkyl grafting and partial chemical reduction with the small-size effect gave rise to outstanding long-term dispersion stability (as long as one month) of RGO-g-OA in the finished oil. Moreover, the friction coefficient and wear volume of finished oil with merely 0.005 wt% RGO-g-OA greatly reduced to 0.065 and 10 316 μm³, decreased by 9.7% and 44%, respectively, compared to those of pristine finished oil, demonstrating remarkable friction reduction and anti-wear performances. Consequently, owing to the characteristics of facile fabrication, durable dispersion stability, and superior tribological performance at an extremely low content, this novel nanoadditive shows a promising application potential in the tribology field.

Long-chain alkyl functionalized ultrafine reduced graphene oxide nanocomposites with outstanding dispersibility and enhanced lubricating performances.     

Essential oil loaded pectin/chitosan nanoparticles preparation and optimization via Box–Behnken design against MCF-7 breast cancer cell lines

In the continuous search for effective cancer treatments, we here report a novel anticancer nanoparticulate system composed of jasmine oil (JO), an essential oil with proven anticancer activity and pectin/chitosan composite nanoparticles (Pec/CS NPs) as encapsulating materials to overcome JO''s solubility and sensitivity problems using a green ionotropic gelation method. Pec/CS/JO NPs were formulated using Box–Behnken design (BBD) to estimate the interactions and effects of studied formulation variables on particle size, zeta potential and encapsulation efficiency to develop an optimized Pec/CS nanoformulation. The nano-encapsulation system preserved the consistency of total phenolic contents in JO and amended its thermal stability by 1.64 fold. The antioxidant potency of JO was enhanced after encapsulation by 96.28%. Consequently, the cytotoxic activity of bare Pec/CS NPs, pure JO and encapsulated JO in Pec/CS NPs against (MCF-7) breast cancer cells and (L-929) normal cells was evaluated using MTT assay. Encapsulated JO was more potent than pure JO with ≈13 fold improvement in anticancer activity, whereas the cell viability of normal cells wasn''t affected but was rather enhanced when treated with Pec/CS NPs.

Pec/CS/JO formulated nanocomposite showed a 13-fold increase in potency against cancer cells, whereas cell viability of normal cells wasn''t affected.     

Molecular weight distribution of raw and catalytic fast pyrolysis oils: comparison of analytical methodologies

Comprehensive analysis of the molecular weight distribution of raw and catalytic fast pyrolysis oils derived from biomass remains a key technical hurdle to understanding oil quality as it relates to downstream use and multiple methods may be necessary to accurately represent all components present. Here, we report the molecular weight distribution metrics of fast pyrolysis (FP) and catalytic fast pyrolysis (CFP) oils as determined by gel permeation chromatography (GPC) combined with UV-diode array (UV), differential refractive index (RI), and multi-angle laser light scattering (MALS) detection. The measured molar mass distributions revealed that FP oil consisted of a higher proportion of larger products relative to the low molecular weight products contained in the CFP oil. GPC/RI and UV methods showed FP oil to have higher weight-average molecular weight (M_w) and number-average molecular weight (M_n) than CFP oil based on elution time. However, GPC/MALS, determined the two oils to have similar overall molecular weight distribution metrics (M_w and M_n) and yielded values significantly higher than those determined by RI and UV detectors relative to external standards. Overall, the use of a multiple detection GPC method could enable a more accurate comparison and determination of true molecular weight metrics of bio-oils.

Comprehensive analysis of the molecular weight distribution of raw and catalytic fast pyrolysis oils remains a key technical hurdle to understanding oil quality and multiple methods may be necessary to accurately represent all components present.     

Development,characterization and application of hydroxypropylmethylcellulose films enriched with cypress seed extract

The phenolic profile of cypress seed extract (CSE) was investigated by means of liquid chromatography with photodiode array and electrospray ionisation mass spectrometric detection (LC/PDA/ESI-MS). The total phenolic (TP) and flavonoid (TF) contents as well as the antioxidant capacity of CSE were determined. The effects of CSE concentration (0.1, 0.3, 0.5, 1, and 2% (w/v)) on the functional properties of hydroxypropylmethylcellulose (HPMC) films were studied. Results showed that CSE presents a good antioxidant capacity due to its high phenolic/flavonoid contents and particularly the presence of bi-flavonoid compounds including cupressuflavone and amentoflavone derivatives. The incorporation of CSE in HPMC films led to a significant decrease in their water vapor permeability (WVP) and enhanced their mechanical strength. The lowest WVP value, the greatest opacity and the highest antioxidant capacity were obtained with the highest CSE concentration. HPMC films with and without CSE were applied on virgin olive oil to study their effect on the oxidative stability of olive oil during accelerated storage by periodically analyzing changes in FTIR spectra and peroxide values. HPMC-2% CSE films were the most effective in lowering light transmission, and consequently decreasing peroxide formation and delaying oxidation of olive oil.

Biodegradable films made from hydroxypropylmethylcellulose and incorporating cypress seed extract were developed and showed good functional properties for active packaging applications.     

Dispersion stability and tribological properties of additives introduced by ultrasonic and microwave assisted ball milling in oil

Graphene and MoS₂ were modified by organic molecules to obtain modified reduced graphene oxide (MRGO) and modified molybdenum disulfide (MMD) powders. MRGO and MMD were uniformly dispersed in base oil (PAO6) by ultrasonic and microwave assisted ball milling (UMBM). This study tested the dispersion stability and tribological properties of additives in the oil, and analyzed the elements of the friction surface. Besides, the mechanism of anti-friction and anti-wear was discussed. The results show that the UMBM method is an effective way to introduce additives in lubricating oil. Compared with direct addition, it can effectively improve the dispersion stability of additives in the oil, so that additives can be better deposited and adsorbed on the friction surface in the friction process, and improve the tribological properties of lubricating oil.

Additives were uniformly dispersed in base oil by ultrasonic and microwave assisted ball milling.     

Molecular selectivity in the water flooding heavy oil process from porous rocks

Water flooding increases the recovery factor of crude oil and has been proven to be an economical and viable technique for enhancing the oil recovery of oil fields. The process has been systematically studied previously, in which the oil was considered a substance of constant composition. However, the molecular selectivity during the water flooding process has rarely been addressed, especially for heavy oil. Herein, the properties and compositional changes of heavy oil have been investigated in a simulated water flooding process at 60 °C and 85 °C. The crude oil and produced oils from different water flooding stages were characterized by gas chromatography, gas chromatography-mass spectrometry, and Fourier transform ion cyclotron resonance mass spectrometry. The results show that with the increase in temperature, the content of resins in the produced oils from different water flooding stages decreases, and the content of asphaltenes increases slightly. The viscosity of the produced oils increases at low temperatures and decreases at high temperatures as the water cut increases. The composition of the produced oils from different water flooding stages is different. Compared with the no water cut and high water cut stages, the changes in the produced oils of the low water cut stages are significant at different temperatures. The molecular selectivity of heteroatoms is higher than that of hydrocarbons in the water flooding process. Water flooding preferentially extracts small-molecule low-carbon hydrocarbons and small-molecule heteroatoms with low condensation degrees. The compositional differences between the produced oils were characterized by the double bond equivalent versus carbon number distribution of the S, N, and O-containing compounds. This study can not only provide some explanations on the viscosity-forming mechanism of heavy oil but also explains the watered-out phenomena in the development of oilfields.

The composition of heavy oil changes during the water flooding process. Water flooding preferentially extracts small-molecular components with the increase in temperature.     

An efficient class of bis-NHC salts: applications in Pd-catalyzed reactions under mild reaction conditions

This study describes an efficient class of bis-N-heterocyclic carbene (bis-NHC) salts that can be easily made from commercially available and inexpensive starting materials. The application of these salts to Pd-catalyzed reactions is described. The palladium (Pd) catalyst generated in situ was highly effective under mild reaction conditions.

This study describes an efficient class of bis-N-heterocyclic carbene (bis-NHC) salts that can be easily made from commercially available and inexpensive starting materials.     

Changes of physicochemical properties,oxidative stability and cellular anti-inflammatory potentials for sea-buckthorn pulp oils during refining

The impact of the refining process on physicochemical properties, oxidative stability and cellular anti-inflammatory potentials of sea-buckthorn pulp oil (SBO) was investigated in this study. The results showed that acid and peroxide values of the tested SBOs decreased significantly after the refining process, while oxidative stability index (OSI) and anti-inflammatory potentials, measured as reduction in cellular inflammatory cytokine production, increased significantly. Interestingly, bleaching caused an unexpected increase in tocopherols as well as the greatest reduction in polycyclic aromatic hydrocarbons (PAHs). According to correlation analyses, tocopherol concentrations were significantly and positively correlated with OSI values and cellular anti-inflammatory potentials, while PHAs were negatively correlated with these factors. In general, refining is an effective way to improve the oxidative stability and anti-inflammatory capacity of SBO.

The impact of the refining process on physicochemical properties, oxidative stability and cellular anti-inflammatory potentials of sea-buckthorn pulp oil (SBO) was investigated in this study.     

Facile fabrication of zinc oxide coated superhydrophobic and superoleophilic meshes for efficient oil/water separation

Zinc oxide (ZnO) coated superhydrophobic and superoleophilic stainless steel meshes are facilely fabricated via chemical immersion growth and subsequent surface modification. The as-prepared meshes show good mechanical durability, chemical stability and corrosion-resistant properties due to a combination of the hierarchical ZnO structure and the low surface energy modification. More importantly, the as-prepared meshes are used for highly efficient separation of various oil/water mixtures. Meanwhile, a new oil skimmer based on the as-prepared mesh is proposed to spontaneously collect floating oil with high separation efficiency and desirable durability.

Zinc oxide coated superhydrophobic and superoleophilic stainless steel mesh was fabricated by a simple and inexpensive approach for efficient oil/water separation.     

Heterostructure of vanadium pentoxide and mesoporous SBA-15 derived from natural halloysite for highly efficient photocatalytic oxidative desulphurisation

Integration between conventional semiconductors and porous materials can enhance electron–hole separation, improving photocatalytic activity. Here, we introduce a heterostructure that was successfully constructed between vanadium pentoxide (V₂O₅) and mesoporous SBA-15 using inexpensive halloysite clay as the silica–aluminium source. The composite material with 40% doped V₂O₅ shows excellent catalytic performance in the oxidative desulphurisation of dibenzothiophene (conversion of 99% with only a minor change after four-cycle tests). These results suggest the development of new catalysts made from widely available natural minerals that show high stability and can operate in natural light to produce fuel oils with ultra-low sulphur content.

New and robust catalysts made from natural minerals that can operate in sunlight to produce fuel oils with ultra-low-sulphur content.     

Surface modification of highly hydrophobic polyester fabric coated with octadecylamine-functionalized graphene nanosheets

This study focuses on the design of highly hydrophobic polyester fabrics (PET) coated with organophilic graphene nanosheets (G-ODA) through a simple, cost-effective and scalable coating method. The organophilic graphene oxide was successfully synthesized by covalently grafting a long chain fatty amine on its surface and was fully characterized by various physicochemical techniques. G-ODA was coated at different loadings onto the PET fabric ranging from 1 to 7 wt% to produce uniformly dispersed PET@G-ODA fabrics with multifunctional performances. FTIR has confirmed the formation of strong interfacial interaction between the PET and G-ODA functional groups. Moreover, the produced PET@G-ODA fabrics resulted in achieving enhanced thermal stability as well as excellent water repellency compared to the pristine PET. Water contact angle measurements showed a tremendous enhancement of surface hydrophobicity up to 148° with 7 wt% loading of G-ODA. Tensile strength tests revealed that our fabric exhibited excellent mechanical properties compared to neat PET. In addition, the designed PET@G-ODA fabrics demonstrated excellent oil/water separation efficiency for different oil/water mixtures. The obtained results are very promising in terms of designing and producing functional PET fabrics with improved thermal and surface proprieties.

This study focuses on the design of highly hydrophobic polyester fabrics (PET) coated with organophilic graphene nanosheets (G-ODA) through a simple, cost-effective and scalable coating method.