Addition Of Methanol Research Articles

Assessing rotation and solvation dynamics in ethaline deep eutectic solvent and its solutions with methanol.

Steady-state and time-resolved fluorescence were used to investigate the solvation of coumarin 153 (C153) and coumarin 343 (C343) in methanol + ethaline binary solutions, a deep eutectic solvent composed of a 1:2 molar ratio choline chloride + ethylene glycol. In addition, time-resolved anisotropy decays were used to determine the solute's rotational reorientation time as a function of viscosity. Measurements were made in solutions covering the entire range of mole fraction. Viscosity measurements were used to characterize the bulk solvent properties, and as expected, addition of methanol resulted in an decreased viscosity, showing an exponential decrease with mole fraction, up to ∼50-fold at xMeOH = 1.0. Probe rotational reorientation times were found to be biexponential at xMeOH < 0.3 for C153 and xMeOH < 0.5 for C343 and monoexponential at richer methanol content. In proportion to viscosity, C153 and C343 average rotation times decreased ∼30-fold from xMeOH = 0 to 0.9 and showed a power law dependence of ∼η0.85. Rotation times approached the stick boundary limit on dilution with methanol. Time-resolved Stokes shifts quantified the solvation dynamics and were nearly single exponential for C153 but were clearly biexponential for C343. Solvation times also tracked with viscosity according to a power law dependence, with exponents of 0.3 and 0.4 for C153 and C343, respectively. The dilution effect of methanol was not linear in proportion to the viscosity change and alone cannot account for the change in solvation. Dilution also showed a different correlation to solvation than did temperature variations to govern the viscosity change.

Lifecycle-based environmental pollution cost analyses of a spark ignition engine fueled with a methanol-gasoline blend

ABSTRACT The purpose of this study is to investigate lifecycle-based environmental pollution cost analyses of a spark ignition engine fueled with a methanol-gasoline blend. In this respect, the experiments are performed at partial loads such as 25 Nm, 50 Nm, 75 Nm, 100 Nm, and full load, whereas lambda and engine speed values are constant at λ = 1 and 2000 rpm, respectively. According to calculated results, lifecycle-based environmental pollution cost analyses are considerably varying from each other. The lowest specific environmental pollution cost and total environmental pollution cost values are 3.893 US cent/kWh and $17,903.89 for methanol-gasoline test fuel at 50 Nm, respectively. In contrast to these, the lowest lifecycle specific environmental pollution cost and the lifecycle-based on total environmental pollution cost values are found to be 5.161 US cent/kWh and $13,786 for gasoline at 100 Nm and full engine load, respectively. The methanol-gasoline test fuel has higher values than gasoline in lifecycle-based specific and total environmental pollution cost at all engine loads. For instance, the average value of lifecycle-based specific and total environmental pollution cost for five loads increased by 11.63% and 11.54% because of methanol addition, respectively. Furthermore, the methanol-gasoline test fuel has longer payback, environmental payback and lifecycle-based environmental payback period values than gasoline at all engine loads. In this respect, the average value of payback, environmental payback, and lifecycle-based environmental payback period values increased by 6.65%, 6.70%, and 19.05% with the addition of methanol. The lowest system total payback period, environmental payback period and lifecycle-based environmental payback period periods are 11.66, 4.646, and 6.15 years for gasoline at full load, 50 Nm, and 100 Nm, respectively. In addition, the optimum engine load, lifecycle-based environmental pollution cost and payback period values found to be 56.48 Nm, $27,850.55, 6.42 year, for gasoline, while 54.95 Nm, $30,138.12, 7.71 year for the MG20, respectively. Interestingly, considering all the results, gasoline usually emerges as a more promising fuel in the lifecycle-based environmental pollution costs than the methanol-gasoline test fuel at all engine loads.

Quantitative profiling of inflammatory and pro-resolving lipid mediators in human adolescents and mouse plasma using UHPLC-MS/MS.

Lipid mediators are bioactive lipids which help regulate inflammation. We aimed to develop an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method to quantify 58 pro-inflammatory and pro-resolving lipid mediators in plasma, determine preliminary reference ranges for adolescents, and investigate how total parenteral nutrition (TPN) containing omega-3 polyunsaturated fatty acid (n-3 PUFA) or n-6 PUFA based lipid emulsions influence lipid mediator concentrations in plasma. Lipid mediators were extracted from plasma using SPE and measured using UHPLC-MS/MS. EDTA plasma was collected from healthy adolescents between 13 and 17 years of age to determine preliminary reference ranges and from mice given intravenous TPN for seven days containing either an n-3 PUFA or n-6 PUFA based lipid emulsion. We successfully quantified 43 lipid mediators in human plasma with good precision and recovery including several leukotrienes, prostaglandins, resolvins, protectins, maresins, and lipoxins. We found that the addition of methanol to human plasma after blood separation reduces post blood draw increases in 12-hydroxyeicosatetraenoic acid (12-HETE), 12-hydroxyeicosapentaenoic acid (12-HEPE), 12S-hydroxyeicosatrienoic acid (12S-HETrE), 14-hydroxydocosahexaenoic acid (14-HDHA) and thromboxane B2 (TXB2). Compared to the n-6 PUFA based TPN, the n-3 PUFA based TPN increased specialized pro-resolving mediators such as maresin 1 (MaR1), MaR2, protectin D1 (PD1), PDX, and resolvin D5 (RvD5), and decreased inflammatory lipid mediators such as leukotriene B4 (LTB4) and prostaglandin D2 (PGD2). Our method provides an accurate and sensitive quantification of 58 lipid mediators from plasma samples, which we used to establish a preliminary reference range for lipid mediators in plasma samples of adolescents; and to show that n-3 PUFA, compared to n-6 PUFA rich TPN, leads to a less inflammatory lipid mediator profile in mice.

Enhancing the expression of recombinant small laccase in Pichia pastoris by a double promoter system and application in antibiotics degradation.

Low-expression levels remain a challenge in the quest to use the small laccase (rSLAC) as a viable catalyst. In this study, a recombinant Pichia pastoris strain (rSLAC-GAP-AOX) producing rSLAC under both AOX and GAP promoters (located in two different plasmids) was generated and cultivated in the presence of methanol and mixed feed (methanol:glycerol). Induction with methanol resulted in a maximum laccase activity of 1200 U/L for rSLAC-GAP-AOX which was approximately 2.4-fold higher than rSLAC-AOX and 5.1-fold higher than rSLAC-GAP. The addition of methanol:glycerol in a stoichiometric ratio of 9:1 consistently improved biomass and led to a 1.5-fold increase in rSLAC production as compared to induction with methanol alone. The rSLAC removed 95% of 5mg/L ciprofloxacin (CIP) and 99% of 100mg/L tetracycline (TC) in the presence of a mediator. Removal of TC resulted in complete elimination of antibacterial activity while up to 48% reduction in antibacterial activity was observed when CIP was removed. Overall, the present study highlights the effectiveness of a double promoter system in enhancing SLAC production.

Stepwise Methanolysis of Waste Cooking Oil Using Immobilized Thermomyces lanuginose Lipase within Ultrasonic-assisted Condition

Biodiesel or fatty acid methyl ester is a fuel derived from vegetable oil and animal fat. In this study, biodiesel is produced from transesterification of waste cooking oil and methanol (methanolysis), using immobilized Thermomyces lanuginose (TLIM) within ultrasonic-assisted conditions. The enzymatic transesterification is used due to environmental concerns and also the high yield of biodiesel. The limitations in the mass transfer rate of the product and longer reaction time have drawn attention to more efficient technology. One of them is ultrasonic-assisted to reduce reaction time and increase the catalytic activity of the enzyme. Various parameters have been examined in this study, such as reaction time, methanol to oil ratio, the effect of temperatures, and temperature dependency of immobilized Thermomyces lanuginose (TLIM). The highest biodiesel yield of 69.3% was obtained after 6 hours of reaction at a temperature of 35°C and using three step-wise addition of methanol to oil ratio 3:1. Our study showed that the TLIM is sensitive to methanol to oil molar ratio above 1:1. Further research on the temperature dependence found that the TLIM activation energy in the reaction is 11.9 kcal/mol, which is within activation energy for an enzymatic reaction.

Frequency-Dependent Sonochemical Processing of Silicon Surfaces in Tetrahydrofuran Studied by Surface Photovoltage Transients.

The field of chemical and physical transformations induced by ultrasonic waves has shown steady progress during the past decades. There is a solid core of established results and some topics that are not thoroughly developed. The effect of varying ultrasonic frequency is among the most beneficial issues that require advances. In this work, the effect of sonication of Si wafers in tetrahydrofuran on the photovoltage performance was studied, with the specific goal of studying the influence of the varying frequency. The applied ultrasonic transducer design approach enables the construction of the transducer operating at about 400 kHz with a sufficient sonochemical efficiency. The measurements of the surface photovoltage (SPV) transients were performed on p-type Cz-Si(111) wafers. Sonication was done in tetrahydrofuran, methanol, and in their 3:1 mixture. When using tetrahydrofuran, the enhanced SPV signal (up to ≈80%) was observed due to increasing sonication frequency to 400 kHz. In turn, the signal was decreased down to ≈75% of the initial value when the frequency is lowered to 28 kHz. The addition of methanol suppressed this significant difference. It was implied that different decay processes with hydrogen decomposed from tetrahydrofuran could be attempted to explain the mechanism behind the observed frequency-dependent behavior.

Co-Nonsolvency Effect in Solutions of Poly(methyl methacrylate)-b-poly(N-isopropylacrylamide) Diblock Copolymers in Water/Methanol Mixtures

The self-assembly of the thermoresponsive amphiphilic diblock copolymer PMMA21-b-PNIPAM283 is studied in different water/methanol mixtures. It consists of a short hydrophobic poly(methyl methacrylate) block and a long thermoresponsive poly(N-isopropylacrylamide) block. Adding methanol as a cosolvent causes the PNIPAM block, which is soluble in both pure water and pure methanol, to collapse due to the so-called co-nonsolvency effect. Meanwhile, the addition of methanol reduces the incompatibility of the PMMA block with water. By means of turbidimetry and differential scanning calorimetry, the solvent-composition-dependent phase diagram is constructed. Dynamic light scattering and synchrotron radiation-based small-angle X-ray scattering provide structural information at 20 °C in dependence on the solvent composition. In water-rich solvent mixtures, self-assembled spherical core–shell micelles are formed. The internal structure of the micelles is adjusted by the solvent compositions in two ways: methanol softens the PMMA micellar core, while it causes the shrinkage of the PNIPAM micellar shell. In methanol-rich solvent mixtures beyond the miscibility gap, the copolymers are molecularly dissolved chains. They are collapsed near the coexistence line, while they become random coils as the methanol content increases. We propose that the internal morphology of the micelles and the conformation of the dissolved chains depend strongly on the solvent composition, as a consequence of the superposed co-nonsolvency effect of PNIPAM and the overall enhanced solvation of PMMA when adding methanol.

Improving the Heterologous Production of Fungal Peroxygenases through an Episomal Pichia pastoris Promoter and Signal Peptide Shuffling System.

Fungal peroxygenases (UPOs) have emerged as oxyfunctionalization catalysts of tremendous interest in recent years. However, their widespread use in the field of biocatalysis is still hampered by their challenging heterologous production, substantially limiting the panel of accessible enzymes for investigation and enzyme engineering. Building upon previous work on UPO production in yeast, we have developed a combined promoter and signal peptide shuffling system for episomal high throughput UPO production in the industrially relevant, methylotrophic yeast Pichia pastoris. Eleven endogenous and orthologous promoters were shuffled with a diverse set of 17 signal peptides. Three previously described UPOs were selected as first test set, leading to the identification of beneficial promoter/signal peptide combinations for protein production. We applied the system then successfully to produce two novel UPOs: MfeUPO from Myceliophthora fergusii and MhiUPO from Myceliophthora hinnulea. To demonstrate the feasibility of the developed system to other enzyme classes, it was applied for the industrially relevant lipase CalB and the laccase Mrl2. In total, approximately 3200 transformants of eight diverse enzymes were screened and the best promoter/signal peptide combinations studied at various cofeeding, derepression, and induction conditions. High volumetric production titers were achieved by subsequent creation of stable integration lines and harnessing orthologous promoters from Hansenula polymorpha. In most cases promising yields were also achieved without the addition of methanol under derepressed conditions. To foster the use of the episomal high throughput promoter/signal peptide Pichia pastoris system, we made all plasmids available through Addgene.

Bio-oil stability through stepwise pyrolysis of groundnut shells: Role of chemical composition, alkali and alkaline earth metals, and storage conditions

Bio-oil obtained from crop residues is unstable because of multiple reactive oxygenated compounds and alkali and alkaline earth metals (AAEMs), which hinder its use as a chemical feedstock. In the current study, stepwise pyrolysis of groundnut shells was performed in three-step (160/200–320/340−600 °C), two-step (320/340−600 °C), and continuous (600 °C) heating regimes to obtain a more stable bio-oil. The stability of bio-oils was compared in terms of changes to their pH, water content, AAEM concentration, and chemical composition over a fixed period. During three-step pyrolysis, 94.85–97.38 % of chemicals (anhydrosugars, organic acids, aldehydes, and ketones) were concentrated in step 2. In contrast, for two-step pyrolysis, 93.14–94.78 % were concentrated in step 1. The AAEMs transferred from groundnut shells to bio-oil were 7.04–9.63 % for three-step, 6.68–11.26 % for two-step, and 11.87 % for continuous pyrolysis. An accelerated aging test (80 °C for 24 h) showed that two-step pyrolysis at 340 °C and 600 °C, produced the most stable bio-oil despite a higher concentration of AAEMs. Further improvement in this bio-oil’s stability was explored by altering storage temperature and adding solvents to the bio-oil. The decrease in concentrations of anhydrosugars and phenolics was <1% after four weeks of storage at 4 °C with the addition of methanol. The obtained results contribute to implementing stepwise pyrolysis units for crop residue management.

Analytical quality by design in the development of a solvent-modified micellar electrokinetic chromatography method for the determination of sitagliptin and its related compounds

A solvent-modified micellar electrokinetic chromatography method was developed following the Quality by Design approach for the simultaneous determination of sitagliptin (SIT), an oral antihyperglycemic drug, and its main impurities derived from the synthesis process. The separation system was identified in the scouting phase and was made by sodium dodecyl sulphate (SDS) micelles with the addition of n-butanol and methanol. The knowledge space was investigated through an asymmetric screening matrix, taking into consideration eight critical method parameters (CMPs) involving the composition of the background electrolyte in terms of buffer concentration and pH, the concentration of surfactants and organic modifiers, and voltage. The critical method attributes (CMAs) were identified as analysis time and the distance between the tail of the electroosmotic flow system peak and the front edge of impurity I1 (sitagliptin triazole hydrochloride). A Box-Behnken Design was used in response surface methodology for calculating the quadratic models relating the CMPs to the CMAs. From the models it was possible to compute the method operable design region (MODR) through Monte-Carlo simulations. The MODR was identified in the probability maps as the multidimensional zone where the risk of failure to achieve the desired values for the CMAs was lower than 10 %. The experimental conditions corresponding to the working point, with the MODR interval, were the following: background electrolyte, 14 (10−18) mM borate buffer pH 9.20, 100 mM SDS, 13.6 (11.1–16.0) %v/v n-butanol, 6.7 (4.5–8.8) %v/v methanol; voltage and temperature were set to 28 kV and 22 °C, respectively. The developed CE method was validated in accordance with International Council for Harmonisation guidelines and was applied to the analysis of SIT tablets. The routine analysis for the quality control of the pharmaceutical product could be conducted in about 11 min.

Effect Methanol, Ethanol, Butanol on the Emissions Characteristics of Gasoline Engine

The increasing volume of motorized vehicles leads to an increase in dependence on fossil fuels and an increase in air pollution. The problem can be reduced by utilizing renewable alcohol fuels such as methanol, ethanol, and butanol. The high number of octane and oxygen content is the main reason. Therefore, this study aims to observe the exhaust emissions of the 160 cc gasoline engine with a mixture of methanol, ethanol, and butanol. The percentage of alcohol used is 0 % to 30 % by volume. The test was carried out in 2000, 3000, and 4000 rpm. The results of the study explained that the use of methanol, ethanol, butanol in the fuel mixture was proven to reduce exhaust emissions. CO and HC emissions decreased as the percentage of alcohol in the fuel increased. The highest reduction in CO and HC emission in methanol blended fuel was 30 %, 94.55 % and 82.71 %, respectively. Meanwhile, CO2 emissions increased by 34.88 % at 2000 rpm engine speed. Based on this test, the addition of methanol to fuel can reduce exhaust emissions better than ethanol and butanol.

An experimental study of engine characteristics and tailpipe emissions from modern DI diesel engine fuelled with methanol/diesel blends

Herein, we investigated and analysed the performance and characteristics of a compression ignition engine on methanol/diesel blends and the impact of engine loads on tailpipe emissions and engine performance. Four combinations of blended methanol were tested and compared with pure diesel. Engine characteristics, such as: brake thermal efficiency, brake specific fuel consumption and brake power were analysed. HCs and CO emissions followed similar trends. The highest HCs concentration reached 40 ppm at lower load (L1) for pure diesel and 5 ppm for blended fuel at a higher load (L5, B40). NOx emissions showed a different trend, showing a higher concentration of 640 ppm for higher load (L5, B40) and the lowest concentration appeared at lower load (L1) for pure diesel. For each individual load, with blended methanol at different percentages, NOx has increased with higher methanol blends. Whilst with HCs, CO emissions were reduced with an increased percentage of methanol addition. Additionally, smoke emissions were significantly reduced by increasing the methanol percentage in methanol/diesel blends. Pure diesel at all engine loads showed higher brake thermal efficiency and lower fuel consumption. The highest brake specific fuel consumption was found at lower load (L1, B40) and reached up to 0.75 g/kWh.

Germany's supreme court rules in Solvay's favour on patent case with Neo

Methanol has been shown to promote the hydrocarbon selective catalytic reduction of NOx with octane and toluene over 2 wt% Ag/Al2O3 catalyst for the first time. In order to understand its role in the reaction fast transient kinetic methods and in situ DRIFTS analysis have been used. The catalytic activity tests showed that the addition of methanol to the HC-SCR reaction results in a significant improvement in the low temperature activity of a Ag/Al2O3 catalyst, despite the fact that methanol on its own is not reactive for the HC-SCR reaction. This promotional effect of methanol is dependent on the concentration of added methanol and is not necessarily associated with a higher concentration of reductant in the SCR feed. The fast transient kinetic analysis has shown that at each temperature the addition of methanol enhances the conversions of both NOx and octane and the production of N2 with high selectivity in comparison with those observed with n-octane or toluene alone. This phenomenon is similar to the effect of H2 which may be associated with the release of hydrogen and ammonia during the transient switches at 250 and 300 °C. Together with the fast transient experiments, the DRIFTS results showed that NCO species are formed when introducing methanol to the n-octane-SCR feed while CN species are removed/consumed from the surfaces of the Ag catalyst. These NCO species formed by adding methanol may play a vital role in promoting the catalytic activity of NOx reduction and methanol itself can be an in situ source for hydrogen formation, which subsequently enhances the SCR reaction.

Photocatalytic degradation of nitrobenzene in wastewater by persulfate integrated with Ag/Pb3O4 semiconductor under visible light irradiation

Nitrobenzene oxidation was executed utilizing an innovative method, in which Ag/Pb3O4 semiconductors irradiated by visible light were used for activation of persulfate into sulfate radicals. Batch mode experiments were accomplished to elucidate the effect of persulfate concentrations and Ag/Pb3O4 dosages on the nitrobenzene oxidation behaviors. The physicochemical properties of original and reacted Ag/Pb3O4 were illustrated by X-ray diffraction analyses, UV-Vis diffuse reflectance spectra, FE-SEM images, EDS analyses, photoluminescence spectra and X-ray photoelectron spectra, respectively. The main oxidant was hypothesized to be sulfate radicals, induced from persulfate caused by photocatalysis of Ag/Pb3O4. It was clearly reflected on the scavenging experiments with addition of benzene, ethanol and methanol individually. As far as degradation pathways concerned, nitrobenzene was essentially transformed into hydroxycyclohexadienyl radicals, and sequentially converted to 2-nitrophenol, 3-nitrophenol or 4-nitrophenol simultaneously. Denitration of nitrophenols gave rise to synthesis of phenol, followed with generation of hydroquinone and p-benzoquinone.

High piezo/photocatalytic efficiency of Ag/Bi5O7I nanocomposite using mechanical and solar energy for N2 fixation and methyl orange degradation

In this work, Ag/Bi5O7I nanocomposite was prepared and firstly applied in piezo/photocatalytic reduction of N2 to NH3 and methyl orange (MO) degradation. Bi5O7I was synthesized via a hydrothermal-calcination method and shows nanorods morphology. Ag nanoparticles (NPs) were photo deposited on the Bi5O7I nanorods as electron trappers to improve the spatial separation of charge carriers, which was confirmed via XPS, TEM, and electronic chemical analyses. The catalytic test indicates that Bi5O7I presents the piezoelectric-like behavior, while the loading of Ag NPs can strengthen the character. Under ultrasonic vibration, the optimal Ag/Bi5O7I presents high efficiency in MO degradation. The degradation rate is determined to be 0.033 min−1, which is 4.7 folds faster than that of Bi5O7I. The Ag/Bi5O7I also presents a high performance in piezocatalytic N2 fixation. The piezocatalytic NH3 generation rate reaches 65.4 μmol L−1 g−1 h−1 with water as a hole scavenger. The addition of methanol can hasten the piezoelectric catalytic reaction. Interestingly, when ultrasonic vibration and light irradiation simultaneously act on the Ag/Bi5O7I catalyst, higher performance in NH3 generation and MO degradation is observed. However, due to the weak adhesion of Ag NPs, some Ag NPs would fall off from the Bi5O7I surface under long-term ultrasonic vibration, which would greatly reduce the piezoelectric catalytic performance. This result indicates that a strong binding force is required when preparing the piezoelectric composite catalyst. The current work provides new insights for the development of highly efficient catalysts that can use multiple energies.

Heavy-oil recovery by combined geothermal energy and cosolvent/water flooding

Water flooding has been accepted as the first-hand strategy for oil recovery as well as for unconventional oil reservoir development. However, a large amount of heavy oil is generally left over after a long period of water flooding due to the figuring effect. In this work, geothermal energy and cosolvents are proposed to assist water flooding for heavy oil recovery. The influences of cosolvents and temperature on the viscosity of heavy oil is first investigated. NMR technique is then applied to investigate the performance of geothermal energy and cosolvents for enhancing heavy oil exploration. Results show that the addition of methanol and ethanol significantly decreases the viscosity of heavy oil as much as 93.95%; in addition, viscosity of heavy oil is reduced as temperature increases. Compared to water flooding, geothermal assisted water flooding recovers 28.3% more oil from the heavy-oil saturated core samples by reducing the viscosity of in-situ heavy oil. The addition of methanol and ethanol into the injected water enables the injected water to enter the smaller pores and recover more heavy oil from such pores. Thereby, the geothermal methanol- and ethanol-assisted water flooding show better performance for enhancing heavy oil exploitation than pure water flooding.

Method optimization of oxylipin hydrolysis in nonprocessed bovine milk indicates that the majority of oxylipins are esterified.

The oxidation of polyunsaturated fatty acids produces bioactive primary oxidation products known as oxylipins. In many biological matrices, the majority of oxylipins are bound (i.e. esterified), and a relatively small proportion (<10%) exists in the free form. The present study tested whether this extends to bovine milk following method evaluation of various extraction and base hydrolysis protocols for measuring bound oxylipins. Free (unbound) oxylipins were also measured. Folch extraction followed by sodium carbonate hydrolysis in the presence of methanol containing 0.1% of acetic acid and 0.1% of butylated hydroxytoluene resulted in greater oxylipin concentrations and better surrogate standard recoveries compared to other methods that did not involve Folch extraction or the addition of methanol with hydrolysis base. Sodium hydroxide was better than sodium carbonate in hydrolyzing bound oxylipins under the same conditions. Milk analysis of oxylipins with mass-spectrometry following Folch extraction and sodium hydroxide hydrolysis revealed that 95% of oxylipins in bovine milk were esterified. Most of the detected oxylipins were derived from linoleic acid, which accounted for 92 and 88% of oxylipins in the free and esterified pools, respectively. These results demonstrate that the majority of bovine milk oxylipins are bound, and that linoleic-acid derived metabolites are the most abundant oxylipin species in free and bound lipid pools. Additional studies are needed to understand the role of different oxylipin pools in both calf and human nutrition. PRACTICAL APPLICATION: A method involving Folch lipid extraction and sodium hydroxide hydrolysis was validated for esterified oxylipin measurements in bovine milk. Application of the method revealed that the majority (∼95%) of oxylipins in bovine milk were bound. Linoleic-acid derived oxylipins were the most abundant species in both bound and free milk fractions (88-92%). The results highlight the presence of a new pool of oxidized lipids in milk, potentially involved in modifying its sensory and nutritional properties.

Statistical Optimization of Biodiesel Production from Salmon Oil via Enzymatic Transesterification: Investigation of the Effects of Various Operational Parameters

The enzymatic transesterification of Atlantic salmon (Salmo salar) oil was carried out using Novozym 435 (immobilized lipase from Candida antartica) to produce biodiesel. A response surface modelling design was performed to investigate the relationship between biodiesel yield and several critical factors, including enzyme concentration (5, 10, or 15%), temperature (40, 45, or 50 °C), oil/alcohol molar ratio (1:3, 1:4, or 1:5) and time (8, 16, or 24 h). The results indicated that the effects of all the factors were statistically significant at p-values of 0.000 for biodiesel production. The optimum parameters for biodiesel production were determined as 10% enzyme concentration, 45 °C, 16 h, and 1:4 oil/alcohol molar ratio, leading to a biodiesel yield of 87.23%. The step-wise addition of methanol during the enzymatic transesterification further increased the biodiesel yield to 94.5%. This is the first study that focused on Atlantic salmon oil-derived biodiesel production, which creates a paradigm for valorization of Atlantic salmon by-products that would also reduce the consumption and demand of plant oils derived from crops and vegetables.

Effect of H2 addition to methanol-gasoline blend on an SI engine at various lambda values and engine loads: A case of performance, combustion, and emission characteristics

The main purpose of this study was to investigate the effects of hydrogen and methanol addition on the engine performance, combustion, and emission characteristics of a spark-ignition engine. The experiments were performed with pure gasoline, methanol-gasoline, and hydrogen-methanol-gasoline fuel blend under various engine loads (25Nm, 50Nm, 75Nm, and 100Nm, 100%), different lambda values (0.8, 1, and 1.2), and a constant engine speed (2000 rpm). The hydrogen energy substitute rate method was applied for hydrogen enrichment that was constituted by 5% of the total input fuel energy. The experimental results indicated that the average values of brake specific fuel consumption were increased by 11.98% with the methanol-gasoline test fuel, while decreased 4.07% with the hydrogen-methanol-gasoline fuel blend. The average values of brake thermal efficiency were slightly increased by 0.07% and 0.61% with the methanol-gasoline and hydrogen-methanol-gasoline fuel blends, respectively. The combustion characteristics were improved after adding the methanol and hydrogen. In this respect, the average ignition delay values decreased by 6.45% with the addition of the methanol in gasoline, while the combustion duration, maximum cylinder pressure, and maximum heat release rate values increased by 0.85%, 1.66%, and 2.32%, respectively. Furthermore, the ignition delay and combustion duration values were substantially affected by the addition of the hydrogen and observed to be at rates of 21.10% and 6.93% reduction, respectively. In addition, the maximum cylinder pressure and maximum heat release rate values were increased by 2.02% and 4.13%. The combustion characteristics improved after the addition of hydrogen and methanol, which also considerably affected the engine performance and emission characteristics. The average values of exhaust gas temperature, hydrocarbon, carbon dioxide were increased by 0.92%, 2.26%, and 0.156% with methanol and the values of carbon monoxide and nitrogen monoxide were decreased by 1.09% and 11.82%, respectively. However, the hydrocarbon, carbon dioxide values were decreased by 13.06%, 3.90% with the hydrogen, while the carbon monoxide, exhaust gas temperature, and nitrogen monoxide were increased by 1.84%, 1.38%, and 31.68%, respectively. Although nitrogen monoxide was considerably decreased by the methanol, a drastic increase was observed with the hydrogen. The optimum brake specific fuel consumption and nitrogen monoxide values occurred between 68.61 Nm and 74.55 Nm of the engine loads for the methanol-gasoline and hydrogen-methanol-gasoline test fuels at λ = 1 and 1.2. Overall, the engine performance, combustion, and emission characteristics were improved by the addition of hydrogen and methanol in the test fuels due to their superior fuel properties compared to gasoline.

An optical study on spray and combustion characteristics of ternary hydrogenated catalytic biodiesel/methanol/n-octanol blends; part П: Liquid length and in-flame soot

Methanol has been considered as a promising alternative fuel for combustion engines. However, it is quite challenging to use it directly in compressed ignition engines because of its ignition issues, especially for low load conditions. In this research, methanol was blended with hydrogenated catalytic biodiesel (HCB) using n-octanol as co-solvent. A fundamental study on spray and combustion characteristics of two ternary blends (68% HCB+17% octanol+ 15% methanol by volume; 58% HCB+17% octanol+ 25% methanol by volume) and the pure HCB was carried out within a constant volume combustion chamber equipped with a single-hole injector. As in Part Ⅰ, the spray morphology, ignition delay, and flame lift-off length have been studied in detail. This part focuses on liquid length and in-flame soot formation of reacting sprays, which were quantified utilizing a diffused back-illumination extinction imaging technique. There is an overlapping area between the fuel liquid phase and flame for all three fuels under all operating points. The reduction on liquid length after ignition is more noticeable for pure HCB than other blends, because of its shorter lift-off length. The results show that the liquid length increases with increasing fraction of methanol in the mixtures, which is mainly governed by the high latent heat of vaporization of methanol. Furthermore, extra methanol addition brings a considerable reduction on in-flame soot production because of the leaner fuel combustion at longer flame lift-off length, as well as the more oxygen content within the blends.